ArticlePDF Available

Abstract

The study aimed at analysing the effects of ejaculate volume on the physical parameters of ejaculates and the sperm morphology of Hypor boars. The analyses involved 114 ejaculates collected from 12 Hypor insemination boars. The ejaculates were classified according to the criterion of ejaculate volume. Three groups were specified: ejaculates with a volume of 251 ml or lower (Group I), ejaculates with a volume of 252-310 ml (Group II), and ejaculates with a volume of 311 ml or higher (Group III). The ejaculates were assessed to identify the basic physical traits and determine the incidence of morphological abnormalities in the spermatozoa, specifying major and minor abnormalities. Furthermore, the morphological structure indices for the spermatozoa were also calculated. Rising ejaculate volume accompanied with a rise in the total number and motility of spermatozoa, and a simultaneous slight fall in sperm concentration in the ejaculates. The ejaculates with the highest volumes turned out to contain more morphologically well-formed spermatozoa. We also determined that rising ejaculate volume is accompanied with increasing sperm dimensions, especially those of the head. The increased parameters were the length and the width of sperm heads, as well as their perimeters and areas. Ejaculate volume has an impact on the shape of Hypor boar spermatozoa. As the ejaculate volume increases, the shape of sperm heads becomes increasingly more oval. Additionally, spermatozoa in ejaculates with greater volumes have larger heads in relation to flagellum length. Özet Çalışmada Hypor erkek domuzların sperm morfolojisi ve ejakülatın fiziksel özellikleri üzerine ejakülat hacminin etkilerini incelemek amaçlandı. Bu amaçla, 12 adet Hypor ırkı suni tohumlama domuzundan alınan 114 ejakülat incelendi. Ejakülatlar hacme göre gruplandırıldı: Numuneler, 251 ml ve altında (Grup 1), 251-310 ml (Grup 2) ve 310 ml ve üstünde (Grup 3) olarak ayrıldı. Sperma, major ve minor morfolojik sperm anomalilerinin sıklığı ve temel fiziksel özellikleri yönünden değerlendirildi. Ayrıca, spermatozoa'nın morfolojik yapısına ait değerler saptandı. Ejakülat hacmi artış ve ejakülasyondaki sperm konsantrasyonunda az miktarda düşüş ile, motilite ve toplam sperm sayısında bir artışla beraber bulundu. En yüksek hacimli ejakülatlarda düzgün yapıda morfolojiye sahip daha fazla sayıda spermatozoa saptandı. Ayrıca, daha yüksek ejakülat hacmiyle birlikte spermatozoonların özellikle baş kısmında olmak üzere ebatlarının büyüdüğü saptandı. Spermatozoonun baş uzunluğu ve genişliği ile çevre uzunluğu ve yüzey alanı büyüdü. Ejakülat hacmi Hypor domuz spermatozoonlarının şekli üzerinde bir etkiye sahipti. Ejakülat hacminin artmasıyla spermatozoa başı daha oval bir şekil aldı. Ek olarak, hacmin artmasıyla ejakülattaki spermatozoa kuyruk uzunluğu ile daha uzun başa sahip olma arasında bir ilişki saptandı.
Abstract
The study aimed at analysing the eects of ejaculate volume on the physical parameters of ejaculates and the sperm morphology of
Hypor boars. The analyses involved 114 ejaculates collected from 12 Hypor insemination boars. The ejaculates were classified according
to the criterion of ejaculate volume. Three groups were specified: ejaculates with a volume of 251 ml or lower (Group I), ejaculates with
a volume of 252-310 ml (Group II), and ejaculates with a volume of 311 ml or higher (Group III). The ejaculates were assessed to identify
the basic physical traits and determine the incidence of morphological abnormalities in the spermatozoa, specifying major and minor
abnormalities. Furthermore, the morphological structure indices for the spermatozoa were also calculated. Rising ejaculate volume
accompanied with a rise in the total number and motility of spermatozoa, and a simultaneous slight fall in sperm concentration in the
ejaculates. The ejaculates with the highest volumes turned out to contain more morphologically well-formed spermatozoa. We also
determined that rising ejaculate volume is accompanied with increasing sperm dimensions, especially those of the head. The increased
parameters were the length and the width of sperm heads, as well as their perimeters and areas. Ejaculate volume has an impact on
the shape of Hypor boar spermatozoa. As the ejaculate volume increases, the shape of sperm heads becomes increasingly more oval.
Additionally, spermatozoa in ejaculates with greater volumes have larger heads in relation to agellum length.
Keywords: Boar, Ejaculate volume, Morphometric traits, Semen, Spermatozoa
Hypor Domuzlarında Sperm Morfolojisi ve Ejakülatların
Fiziksel Özellikleri Yönünden Ejakülat Hacminin Önemi
Özet
Çalışmada Hypor erkek domuzların sperm morfolojisi ve ejakülatın fiziksel özellikleri üzerine ejakülat hacminin etkilerini incelemek
amaçlandı. Bu amaçla, 12 adet Hypor ırkı suni tohumlama domuzundan alınan 114 ejakülat incelendi. Ejakülatlar hacme göre
gruplandırıldı: Numuneler, 251 ml ve altında (Grup 1), 251-310 ml (Grup 2) ve 310 ml ve üstünde (Grup 3) olarak ayrıldı. Sperma, major ve
minor morfolojik sperm anomalilerinin sıklığı ve temel fiziksel özellikleri yönünden değerlendirildi. Ayrıca, spermatozoa’nın morfolojik
yapısına ait değerler saptandı. Ejakülat hacmi artış ve ejakülasyondaki sperm konsantrasyonunda az miktarda düşüş ile, motilite ve
toplam sperm sayısında bir artışla beraber bulundu. En yüksek hacimli ejakülatlarda düzgün yapıda morfolojiye sahip daha fazla sayıda
spermatozoa saptandı. Ayrıca, daha yüksek ejakülat hacmiyle birlikte spermatozoonların özellikle baş kısmında olmak üzere ebatlarının
büyüdüğü saptandı. Spermatozoonun baş uzunluğu ve genişliği ile çevre uzunluğu ve yüzey alanı büyüdü. Ejakülat hacmi Hypor domuz
spermatozoonlarının şekli üzerinde bir etkiye sahipti. Ejakülat hacminin artmasıyla spermatozoa başı daha oval bir şekil aldı. Ek olarak,
hacmin artmasıyla ejakülattaki spermatozoa kuyruk uzunluğu ile daha uzun başa sahip olma arasında bir ilişki saptandı.
Anahtar sözcükler: Erkek domuz, Ejakülasyon hacmi, Morfolojik özellikler, Sperma, Sperm
The Importance of Ejaculate Volume for the Physical Parameters
of Ejaculates and Sperm Morphology of Hypor Boars
Krzysztof GÓRSKI 1 Stanisław KONDRACKI 1 Anna WYSOKIŃSKA 1 Anna NAZARUK 1
1Siedlce University of Natural Sciences and Humanities, Department of Bioengineering and Animal Husbandry, Faculty
of Natural Sciences, Prusa 14, 08-110 Siedlce - POLAND
INTRODUCTION
The efficacy of insemination largely depends on the
quality of spermatozoa inferred from analyses of sperm
morphology [1,2]. Sperm quality can be also determined
on the basis of an analysis of the damage to the sperm
membrane [3], the state of chromatin structure, the anti-
oxidative potential of the spermatozoa, apoptotic changes
or on the basis of sperm ATP level assays [4,5].
Morphological abnormalities in spermatozoa reduce
male fertility [6]. Particular individuals exhibit dierences
in the quality of spermatozoa they produce. This includes
dierence in the incidence of spermatozoa with morpho-
İleşim (Correspondence)
+48 25 6431378; Fax: +48 25 6431272
gorki@uph.edu.pl
KafKas Universitesi veteriner faKUltesi Dergisi
JoUrnal Home-Page: http://vetdergi.kafkas.edu.tr
online sUbmission: http://vetdergikafkas.org
Research Article
Kafkas Univ Vet Fak Derg
22 (4): 493-501, 2016
DOI: 10.9775/kvfd.2015.14772
Article Code: KVFD-2015-14772 Received: 01.12.2015 Accepted: 30.03.2016 Published Online: 01.04.2016
494
The Importance of Ejaculate ...
logical abnormalities [7]. The shape and dimensions of
spermatozoa are also important. Their dimensions and
shapes determine their motility and capacity to penetrate
the egg [8]. This issue has been dealt with by numerous
researchers who concentrated on the variation in morpho-
metric parameters of spermatozoa, depending on the
physical traits of the ejaculates produced by the sires [9,10].
It is believed that the presence of spermatozoa with head
abnormalities in the semen can be the reason for reduced
embryo quality [11] and miscarriages in the initial period of
pregnancy [12].
The size and shape of the sperm head is a species-related
trait. However, dierences have been identified between
males representing dierent breeds of the same species,
or even between particular individual animals [13]. Some
scientists believe that motor parameters of spermatozoa
depend on their sizes and shapes [14-16]. This has impact on
the competitiveness of spermatozoa in the reproductive
organs of the female. Faster and viable spermatozoa
undergo spontaneous selection following capacitation.
Spermatozoa negotiate a long way in the reproductive
tract of the female, surmounting the immunological barrier,
disadvantageous pH, complex oviduct topography and
the untoward conditions prevalent there [17].
The volume of ejaculated semen varies among animals
depending on nutrition, genetics, breed and management [18].
High-volume ejaculates are considered to be particularly
useful for insemination because they make it possible to
prepare numerous insemination doses containing the
required numbers of spermatozoa. Ejaculate volume is also
important for fertilization efficacy and embryo survival [19].
Semen volume aects the distribution of spermatozoa [20].
Increased ejaculate volume positively inuences the transport
of semen by stimulating the central layer of the uterine
accelerate its contractions and inducing the pituitary body
to release hormones that stimulate contractions of the
smooth muscles of the matrix [19]. Ejaculate volume may
also aect the quality dimensions and shape of sperms,
as well as their motor parameters that determine their
fertilizing ability. Currently, there are studies that indicate a
connection between the sperm morphometric parameters
and concentration in the ejaculates of boars [9].
The present study was aimed at analysing the relation-
ship between ejaculate parameters and sperm morphology
and the volume of ejaculates produced by Hypor boars, on
the basis of physical traits of the ejaculates, morphometric
measurements of the spermatozoa, and an evaluation of
the incidence of morphological sperm abnormalities.
MATERIAL and METHODS
The study concerned 114 ejaculates collected from 12
Hypor boars used at three insemination centres. The boars
(aged 8 to 18 months), were managed in accordance with
the rules of animal welfare [21]. The individual pen area was
10 m2/boar, and the pen had a concrete slatted oor. The
boars were fed according to Swine Nutrition Requirements [22],
with ad libitum access to water. Temperature, relative
air humidity, and atmospheric pressure were measured
during semen collections. Temperature was measured
with a precision of one degree Celsius. Humidity, expressed
as a percentage, was measured with a precision of one
percentage point. Temperature and humidity was recorded
using a thermo-hygrometer TERMIK PLUS (1000209, Termo-
produkt, PL). Atmospheric pressure was measured using an
ADLER barometer (Bar 003, Demus, PL) with a resolution
one hPa. Relative humidity was close to 70%. The air
temperature in the boar pens was 16ºC (average minimum
13ºC and maximum 21ºC). Air pressure inside the buildings
averaged 1005 hPa (min. 987 hPa, max. 1016 hPa). Ejaculates
were collected using the manual method [23] in one-month
intervals over a period of nine months. A total of 114
ejaculates were collected from July 2013 to April 2014.
Each boar provided at least 10 ejaculates for the analysis. The
ejaculates were grouped according by volume as follows:
Group I : ejaculates with a volume below 251 ml - 32
ejaculates,
Group II : ejaculates with a volume between 251 ml and
310 ml - 38 ejaculates,
Group III : ejaculates with a volume above 310 ml - 44
ejaculates.
The following physical parameters were determined
in the freshly collected ejaculates: ejaculate volume (ml),
sperm concentration (x106/ml), sperm motility (%), total
number of spermatozoa (x109), and number of insemination
doses per ejaculate (n). Ejaculate volumes were determined
by weight, without the gelatinous fraction, using electronic
scales. Sperm concentration in the ejaculates was determined
with a photometric method, using a spectrophotometer
(IMV Technologies, France). Sperm motility was evaluated
with a Nikon Eclipse 50i light microscope equipped with
a heated stage. A sample of 5 µl of sperm suspension was
placed on a pre-warmed slide and sealed with a coverslip
at 37ºC. Under 200x magnification, the percentage of
normally motile spermatozoa was determined in the
overall number of sperms present in the field of vision of
the microscope. The total number of motile spermatozoa
and the number of insemination doses per ejaculate were
calculated using SYSTEM SUL (v. 6.35; Gogosystem, Poland)
software package.
Semen samples from the collections were used to
prepare microscopic slides. The slides for morphological
analyses were stained using eosin and gentian violet,
according Kondracki et al.[24]. Microscopic analyses of
the smears were performed under 100x magnification
with immersion lenses, using the Nikon Eclipse 50i light
microscope. The morphology of 500 spermatozoa was
assessed per slide, identifying the number of well-formed
and malformed spermatozoa and differentiating those
495
GÓRSKI, KONDRACKI
WYSOKIŃSKA, NAZARUK
with primary and secondary changes, according to Blom’s
classification [25].
Also, sperm morphometric measurements were carried
out on 15 randomly selected normal spermatozoa in each
slide. The measurements were performed using a suite for
computer image analysis (Screen Measurement v. 4.1),
according to methodology proposed by Kondracki et al.[26].
The following sperm measurements were taken: head
length (µm), head width (µm), head area (µm2), head peri-
meter (µm), agellum length (µm), and total length (µm).
The following morphological indices were calculated on
the basis of the measurements:
head width/head length,
head length/total length,
head length/agellum length,
agellum length/total length,
head perimeter/total length,
head area/total length,
head lengthxwidth/total length.
Experimental data were analysed using a program
STATISTICA® 10 PL (StatSoft, Tulsa, USA) [27]. All results
are expressed as mean (X) ± standard deviation (Sx). The
obtained material was statistically analysed according to
the following mathematical model:
Yij = µ + ai + eij
Where: Yij is the value of the analysed parameter, µ is
the population mean, ai is the eect of ejaculate volume,
eij is the error. The significance of the dierences between
the groups was assessed with the Tukey test at P≤0.05
and P≤0.01.
RESULTS
Table 1 contains data on the physical parameters of
the Hypor boar ejaculates in relation to ejaculate volume.
The data reveal that ejaculate physical parameters are
correlated with ejaculate volume. An increase in ejaculate
volume was accompanied by a decrease in sperm concen-
tration and an increase in sperm motility. With an increase
in volume, the total number of sperm and the number of
insemination doses per ejaculate significantly increased too.
Group I, which comprised the lowest-volume ejaculates,
showed the highest sperm concentrations, which averaged
430.66 x 106/ml and were by more than 18 x 106/ml higher
than in Group II, and by nearly 29 x 106/ml higher than in
Group III, the one with the highest ejaculate volumes. These
dierences were not, however, statistically confirmed.
The data in Table 1 show that spermatozoa in the higher-
volume ejaculates have greater progressive motility. Group
III, comprising ejaculates with the highest volume, was
found to contain spermatozoa with the highest motility.
The percentage of motile spermatozoa in the ejaculates
from this group was more than 3% higher than in Group II
(P≤0.01) and almost 5.5% higher than in Group I (P≤0.01).
The highest sperm counts were found in Group III. The
ejaculates in this group contained over 114 billion spermato-
zoa with progressive motility, over 26 billion more than
those in Group II (P≤0.01) and approximately 40 billion
more than those in Group I, with the lowest volumes
(P≤0.01). The number of spermatozoa in the ejaculate also
determines the number of insemination doses that can be
prepared out of the ejaculate. The most numerous doses
were prepared from the ejaculates in Group III, those with
the highest volumes. Each ejaculate in this group provided
more than 37 insemination doses, approximately 8.4 doses
more than the ejaculates in Group II and over 13 doses more
than the ejaculates in Group I (P≤0.01). Table 2 contains the
results of the analysis of morphological abnormalities in
the spermatozoa.
The mean percentage of normally formed spermatozoa
remained within the range from 94.72% to 96.90%. The
fewest spermatozoa with normal morphology were found
in the ejaculates in Group III. The data presented in Table 2
show Hypor boar semen quality to be very high. The mean
percentage of spermatozoa with major morphological
abnormalities did not exceed 1.71%. The differences
Table 1. Physical traits of ejaculates in relation to ejaculate volume
Tablo 1. Ejakülat hacmne lşkn ejekülatların fzksel özellkler
Specification Groups & Ejaculate Volume (ml)
I (< 251) II (251-310) III (> 310)
Number of ejaculates (n) 32 38 44
Ejaculate volume (ml) X±Sx 217.19±33.14A284.47±15.54B364.09±46.37C
Spermatozoa concentration (x 106/ml) X±Sx 430.66±131.65 412.50±129.98 401.86±103.20
Percentage of spermatozoa with progressive motility (%) X±Sx 73.44±4.82a75.79±5.00b78.86±3.21c
Total number of spermatozoa (x 109) X±Sx 75.21±38.57a88.39±25.15b114.58±18.54c
Number of insemination doses per ejaculate (n) X±Sx 24.22±8.49A29.37±8.78B37.75±8.00C
a,b Dierences between average values, represented by dierent letters in the same row, are important (P≤0.05); A,B Dierences between average values,
represented by dierent letters in the same row, are important (P≤0.01)
496
The Importance of Ejaculate ...
between the groups were slight and statistically un-
confirmed. The highest percentage of spermatozoa with
major abnormalities was found in the semen of the boars
with the highest ejaculate volumes. Among the major
morphological abnormalities, cytoplasmic droplets in the
proximal position in the spermatozoa were most frequent.
The mean percentage of spermatozoa with this defect was
low and did not exceed 0.5% (Fig. 1). The highest numbers
of sperm with minor morphological abnormalities were
found in the semen of Group III (3.60%). The dierences
between the groups were, however, low and statistically
non-significant.
The data in Table 2 suggest that the volume of ejaculates
collected from Hypor boars insignificantly affected the
frequency of morphological abnormalities in the spermato-
Fig 1. Frequency of occurrence of chosen anomaly
of morphological spermatozoa depending on the
ejaculate volume
Şekl 1. Ejakülat hacmne lşkn seçlmş morfolojk
sperm anomallernn görülme sıklığı
Table 2. Frequency of spermatozoa with morphological changes in relation to ejaculate volume
Tablo 2. Ejakülat hacmne lşkn morfolojk değşklklere sahp spermatozoa sıklığı
Specification Groups & Ejaculate Volume (ml)
I (< 251) II (251-310) III (> 310)
Number of ejaculates (n) 32 38 44
Ejaculate volume (ml) X±Sx 217.19±33.14A284.47±15.54B364.09±46.37C
Percentage of normal spermatozoa (%) X±Sx 96.08±3.20B96.90±2.63B94.72±3.72A
Spermatozoa with major abnormalities (%) X±Sx 1.09±1.08 0.91±1.80 1.71±2.05
Spermatozoa with minor abnormalities (%) X±Sx 2.88±2.69 2.18±1.81 3.60±2.93
A,B Dierences between average values, represented by dierent letters in the same row, are important (P≤0.01)
Table 3. Morphometric traits of spermatozoa with regard to ejaculate volume
Tablo 3. Ejakülat hacmne lşkn morfometrk spermatozoa özellkler
Specification Groups & Ejaculate Volume (ml)
I (< 251) II (251-310) III (> 310)
Number of ejaculates (n) 32 38 44
Ejaculate volume (ml) X±Sx 217.19±33.14A284.47±15.54B364.09±46.37C
Head length (µm) X±Sx 8.99±0.55 9.10±0.56 9.19±0.46
Head width (µm) X±Sx 4.73±0.32 4.85±0.30 5.02±0.34
Head perimeter (µm) X±Sx 23.24±1.02 23.59±1.14 23.75±1.32
Head area (µm2) X±Sx 37.88±4.39A39.16±4.57AB 40.53±4.28B
Flagellum length (µm) X±Sx 43.19±1.12a43.84±1.16b43.59±1.37ab
Total length (µm) X±Sx 52.18±1.00A53.02±1.15B52.80±1.62AB
a,b Dierences between average values, represented by dierent letters in the same row, are important (P≤0.05); A,B Dierences between average values,
represented by dierent letters in the same row, are important (P≤0.01)
497
zoa. The results of the morphometric measurements of the
spermatozoa are presented in Table 3.
The data in Table 3 show that the spermatozoa in
the ejaculates with the highest volumes (Group III) have
larger head dimensions than those in the ejaculates
with intermediate and low volume (Group II and I). The
head lengths and widths increase with ejaculate volume.
The spermatozoa in the ejaculates with the highest
volumes (Group III) had 0.17 µm wider heads than those
in the ejaculates in Group II (P≤0.05) and 0.29 µm wider
heads than the spermatozoa in Group I (P≤0.01). The
spermatozoa in the ejaculates of the highest volumes were
also characterized by the largest head areas. The head
area exhibits a clear rising trend in line with the increase in
ejaculate volume (P≤0.01).
Sperm agella in the ejaculates in Group II were on
average 0.65 µm longer than those in in Group I (P≤0.05),
and 0.25µm longer compared to Group III. The spermatozoa
total length was also the greatest in the ejaculates in Group
II, principally due to the longer agella. Table 4 contains
data on the structural indices defining the sperm shape.
The data in Table 4 suggest that the eect of ejaculate
volume on the shape of Hypor boar spermatozoa is non-
significant. Most of the structural sperm morphology
indices assumed similar values in all groups, and the
observed dierences largely remained within the range of
statistical error. It was recorded that the spermatozoa in the
ejaculates with the lowest volume (Group I) had the most
elongated heads, and as the ejaculate volume grew, the
shape of the sperm heads turned increasingly more oval.
This has been confirmed in the head width/head length
index, the highest in the ejaculates in Group III - 1.90 times
higher than in Group I (P≤0.01). The data in Table 4 also
show that as the ejaculate volume rises, the proportions
between the spermatozoa head and the agellum change
as well. With an increase in ejaculate volume, the head
area/total length and head length x width/total length
ratios also increased. Both indices were higher in Group III,
compared to those in Groups II and I (P≤0.05). This suggests
that spermatozoa in ejaculates with higher volumes have
larger heads in relation to the agellum length.
DISCUSSION
The ejaculate volume has a physiological basis and is
associated with the secretory function of the accessory
sexual glands, which produce seminal plasma forming
environment for development, and existence of sperm.
Functionality of the accessory sexual glands depends on
many factors including genetic and non-genetic factors.
Important for the physiology of plasma secretion of semen
components is sexual development of pig males. The
sexual development of pig males is not over at 8-9 months
of age, when boars start to be used for insemination, but
proceeds until a much more advanced age. Some authors
have reported that boar ejaculate volume and sperm
count of the boars grows until the age of around 27-28
months [28,29]. The further development of sexual glands in
sexually mature and active breeding boars is confirmed
by testicular morphology analysis. It was shown that
boar testes increase in size until the age of 20 months [30].
Oestrogens play a crucial role in the control of testicular
development and functionality [31,32]. Dynamically rising
weight of testes during pubescence as well as the number
of reproductive and somatic cells within the parenchyma
of testes may be determined by oestrogen levels.
An essential parameter in the qualitative assessment
of boar semen is the percentage of sperm with superior
motility. The reason is that motility is a symptom of viability
and indirectly reveals the fertilization capability of sperma-
tozoa. Acceptable, fertilisation-capable boar semen should
contain at least 70% of spermatozoa with progressive
rectilinear motion [33]. The data of the present study showed
GÓRSKI, KONDRACKI
WYSOKIŃSKA, NAZARUK
Table 4. Morphometric indices of spermatozoa in relation to ejaculate volume
Tablo 4. Ejakülat hacmne lşkn morfometrk spermatozoa endeksler
Specification Groups & Ejaculate Volume (ml)
I (< 251) II (251-310) III (> 310)
Number of ejaculates (n) 32 38 44
Ejaculate volume (ml) X±Sx 217.19±33.14A284.47±15.54B364.09±46.37C
Head width/head length X±Sx 52.71±3.08A53.42±2.55AB 54.61±2.88B
Head length/total length X±Sx 17.23±1.09 17.15±0.96 17.40±0.66
Head length/agellum length X±Sx 20.84±1.59 20.76±1.40 21.09±0.99
Head area/total length X±Sx 82.76±1.09 82.69±1.31 82.54±0.79
Head length x width/total length X±Sx 44.54±2.09 44.48±1.94 44.96±1.69
Perimeter of the head/total length X±Sx 72.61±8.50a73.79±7.94ab 76.66±6.82b
Flagellum length/total length X±Sx 81.79±9.54a83.46±8.94a87.37±7.88b
a,b Dierences between average values, represented by dierent letters in the same row, are important (P≤0.05); A,B Dierences between average values,
represented by dierent letters in the same row, are important (P≤0.01)
498
The Importance of Ejaculate ...
the spermatozoa in all the analysed groups having a good
motility, much above the values reported by Shipley [34].
It was essential to identify the positive eect of ejaculate
volume on sperm motility. Raising ejaculate volume was
accompanied with a significant increase in sperm motility.
Numerous factors affecting sperm motility have been
reported. Some authors have reported the negative impact
of morphological defects on sperm motility [35], while
others have pointed out the considerable impact of the
hyperosmotic environment of spermatozoa on their
motility [36]. Frequent causes of reduced sperm motility
include spermatogenetic disorders, anomalies in the
functioning of the epididymal epithelium and debilitated
functioning of the additional sexual glands [7]. The correlation
between sperm motility and the physical parameters of the
ejaculate has not been clearly confirmed yet. Publications
on the subject provide inconclusive observations. The
study of Pietrain boars by Kondracki et al.[9] showed the
highest motility in spermatozoa in ejaculates with the
lowest volumes. The progressively motile spermatozoa
identified in the previous study ranged from 75 to 79%, and
was slightly higher in ejaculates with the lowest volumes,
i.e. contrarily to the correlation observed in this study. The
observed changes were, however, non-significant, and
the percentage of spermatozoa with progressive motility
was not too much. Studies of the importance of sperm
concentration have revealed that sperm motility is not
in significant correlation with sperm concentration in
the ejaculate [37,38]. There was no correlation between sperm
motility and the total number of spermatozoa in the
ejaculate has been identified either [17]. The results of the
present study showed that sperm concentration was
slightly higher in ejaculates with lower volumes. This confirms
the existence of an inversely proportional correlation
between ejaculate volume and sperm concentration in
boar ejaculates, as identified in previous studies [24,39].
The total number of sperm increased with ejaculate
volume. The differences were significant and very
pronounced. This is consistent with the expectations,
since the content of motile spermatozoa in the ejaculate
depends on ejaculate volume and sperm concentration.
A directly proportional correlation between the number
of spermatozoa and ejaculate volume has also been
observed in other studies [9].
The results of the present study justify the conclusion
that ejaculate volume affects sperm morphology. The
spermatozoa in ejaculates with dierent volumes dier
in their sizes and shapes, as well as in the incidence of
morphological abnormalities. The spermatozoa in the
ejaculates with the highest volumes (above 310 ml) were
larger in size than those in the ejaculates in Group I - with
the lowest volumes (below 251 ml). Sperm size aects
the motility and fertilization capacity [14,30]. According to
Noorafshan & Karbalay-Doust [16], sperm length is positively
correlated with the speed of sperm motion. Spermatozoa
with longer mid-pieces and agella have stronger tails [40].
The correlation between agellum length, and primarily
mid-piece length, and sperm motility has also been
revealed [14,15,41].
It is probable that, sperm mid-piece length can
be associated with the level of energy originating in
mitochondria [42]. Spermatozoa with longer agella are
more competitive since they might reach the egg faster. The
present authors found that spermatozoa with the longest
flagella were present in ejaculates with intermediate
volumes (251-310 ml). A study by Marmor and Grob-
Menendez [43] revealed that spermatozoa with low motility
could have agella that are shorter by as much as 50%. The
results of the above study were confirmed by Noorafshan
and Karbalay-Dust [16]. The data presented in this work
also validate this correlation, because the lower agellum
length in ejaculates containing spermatozoa with low
motility was statistically confirmed. The interrelation between
agellum length and ejaculate parameters has already
been identified in several studies [44,45]. It has been revealed
that ejaculates with a high sperm concentration contain
spermatozoa with shorter agella [37,46]. However, no clear-
cut correlation was identified between agellum length
and the total number of spermatozoa in the ejaculate [17].
The rising ejaculate volume was accompanied with
increasing sperm head dimensions, including the length,
width, perimeter and area (Table 3). The sperm head
contains the cellular nucleus, which is the primary carrier
of genetic information transferred during fertilization.
The variation in the dimensions of sperm heads can stem
from dierences in chromatin structure [47]. Some reports
informed that even slight modifications in the sperm
head shape can be associated with changes in chromatin
structure in the cellular nucleus [48], leading to reduced
fertility [49]. A correlation has been found between sperm
head dimensions and male fertility. It was observed that
the spermatozoa of males with higher fertility had narrower
and shorter heads [50,51]. The studies by Villalobos et al.[52]
demonstrated a positive correlation between fertility and
spermatozoa head morphometry in swine. It was concluded
that males with high fertility showed the values of 8.9 µm
in length and 4.5 µm in width. The data of the present
work revealed that the spermatozoa in the ejaculates
with the lowest volumes had the lowest head dimensions.
Their heads were shorter and narrower than the heads of
spermatozoa in the ejaculates with higher volumes. The
association of sperm head dimensions with the physical
parameters of ejaculates has also been identified in other
studies [9]. Sperm head dimensions have been observed to
be dependent on the sperm concentration in bull [24] and
boar ejaculates [37,38].
The head shape can be significant in the context of
sperm motility. Spermatozoa with an elongated head
shape move faster than those with rounded heads [53]. The
current data showed that the spermatozoa in the ejaculates
499
with the lowest volumes (Group I) had the most elongated
heads, and as the ejaculate volume increases, the shape
of the sperm heads turned increasingly more oval (Table
4). Helfenstein et al.[54] have reported the existence of a
correlation between the length of the head and agellum
and the speed of sperm motion. Spermatozoa with a
lower ratio of head length to tail length move faster.
Considering the results of the experiment, this refers to
the spermatozoa from the ejaculates classified in Group II
in terms of the volume.
Sperm head dimensions can be aected by the manner
of storage and preservation of semen [55,56]. A study by
Hidalgo et al.[56] revealed that buck sperm heads in refri-
gerated were smaller than those in fresh semen. This was
explained with the damage to or loss of the acrosome, or a
possible change in sperm chromatin structure as a result
of refrigeration. The detection of abnormalities in sperm
heads makes it possible to recognize fertile animals and
those with reduced fertility [57]. Morphometric analyses of
ram spermatozoa have revealed that sires with reduced
fertility have larger sperm heads than fertile males [58].
The reason for the increase in head size can be disordered
spermatogenesis, or changes in chromatin structure during
the maturation and transport of spermatozoa. Sperm head
defects often cause deterioration in the quality of embryos
and lead to miscarriages in the first period of pregnancy [12,59].
The data presented in this work indicate a moderate
correlation between the incidences of sperm morphological
abnormalities and ejaculate volume. However, ejaculates
with the highest volumes had the lowest proportions of
spermatozoa with correct morphology. The presence of
morphologically abnormal spermatozoa reduces male
fertility and was an index of a reduced performance of the
seminiferous epithelium. The incidence of morphological
abnormalities in spermatozoa can result from the inuence
of seasonal factors [60], genetic conditions [12,61], and individual
predispositions [62]. The incidences of morphologically ab-
normal spermatozoa also depend on feeding factors [63].
Large differences in the frequency of morphological
abnormalities in spermatozoa have also been identified
in relation to the age of sires [28,64-66].
Boars with normal fertility always have a certain
percentage of morphologically abnormal spermatozoa [63].
A maximum of 15% spermatozoa with major and 10-15%
with minor abnormalities is acceptable. The presence of
spermatozoa with major abnormalities that have appeared
during spermatogenesis is particularly disadvantageous. A
high percentage of spermatozoa with major modifications,
especially acrosome defects, substantially reduces the
chances for insemination. The data presented in this
study showed that the samples of spermatozoa with
major abnormalities was low and did not exceed 1.71%
in any of the groups. Among the major morphological
abnormalities, the proximal cytoplasmic droplet in the
spermatozoa was the most frequent defect. Such defects
result from anomalies in sperm maturation. The reason
for the appearance of the abnormalities can be a short
a time of sperm maturation in the epididymal duct [67].
It should be noted that the incidence of the tail defects
could be a consequence of an osmotic dierence between
the spermatozoa and the solution in which the sample
is immersed [68]. According to Martin-Rillo et al.[69], a
maximum of 20% spermatozoa with a proximal droplet is
acceptable in collected semen. Any amount in excess of this
level leads to a considerable reduction of male fertility [70].
Ejaculate parameters depend on the volume of
produced ejaculates. The rise in ejaculate volume was
accompanied with an increase in the total number and
motility spermatozoa, as well as with a concomitant slight
fall in sperm concentration. Ejaculates with the highest
volume were highly usable for preparation of more
insemination doses. Ejaculates with the highest volumes had
a larger proportion of spermatozoa with normal morpho-
logy. However, ejaculate volume does not substantially
aect the frequency of morphological sperm abnormalities
in Hypor boar ejaculates. Ejaculate volume influences
morphometric parameters of Hypor boar spermatozoa. The
rise in ejaculate volume is accompanied with an increase
in sperm dimensions, especially with regard to the sperm
head. The increased parameters were the length and the
width of sperm heads as well as their perimeters and areas.
Ejaculate volume had an impact on the shape of Hypor boar
spermatozoa. As the ejaculate volume increases, the shape
of the sperm heads changes from elongated to increasingly
more oval. Spermatozoa in ejaculates with higher volume
had a larger heads in relation to the flagellum length.
When using Hypor boars for insemination purposes, it is
preferred to choose sires with a high ejaculatory efficacy
and producing ejaculates of high volume. Such ejaculates
allow not only for generating more insemination doses,
but also doses including spermatozoa of higher mobility
and quality.
REFERENCES
1. De Vos A, Van De Velde H, Joris H, Verheyen G, Devroey P, Van
Steirteghem A: Inuence of individual sperm morphology on fertilization,
embryo morphology, and pregnancy outcome of intracytoplasmic sperm
injection. Fertil Steril, 79, 42-48, 2003. DOI: 10.1016/S0015-0282(02)04571-5
2. Knecht D, Środoń S, Duziński K: The inuence of boar breed and
season on semen parameters. S Afr J Anim Sci, 44, 1-9, 2014. DOI: 10.4314/
sajas.v44i1.1
3. Wysokińska A, Kondracki S: Assessment of changes in sperm
cell membrane integrity occurring during the storage of semen from
genetically dierent males using two diagnostic methods. Can J Anim Sci,
94, 601-606, 2014. DOI: 10.4141/cjas2013-095
4. Waberski D, Magnus F, Ardon F, Petrunkina AM, Weitzke KF, Töpfer-
Petersen E: Binding of boar spermatozoa to oviductal epithelium in vitro
in relation to sperm morphology and storage time. Reproduction, 131,
311-318, 2006. DOI: 10.1530/rep.1.00814
5. Wolf J: Genetic parameters for semen traits in AI boars estimated from
data on individual ejaculates. Reprod Domest Anim, 44, 338-344, 2009.
DOI: 10.1111/j.1439-0531.2008.01083.x
6. Çebi Şen Ç, Faundez R, Jurka P, Akçay E, Petrajtis-Golobow M,
GÓRSKI, KONDRACKI
WYSOKIŃSKA, NAZARUK
500
The Importance of Ejaculate ...
Ambarcıoğlu P: Evaluation of the canine epididymal sperm morphology
with two dierent staining methods, one fixative solution and motile
sperm organelle morphology examination (MSOME). Kafkas Univ Vet Fak
Derg, 22, 57-62, 2016. DOI: 10.9775/kvfd.2015.13887
7. Pinart E, Camps R, Briz MO, Bonet S, Egozcue J: Unilateral spontaneous
abdominal cryptochidism: Structural and ultrastructural study of sperm
morphology. Anim Reprod Sci, 49, 247-268, 1998. DOI: 10.1016/S0378-
4320(97)00074-2
8. Suarez S: Interactions of spermatozoa with the female reproductive
tract: Inspiration for assisted reproduction. Reprod Fertil Dev, 19, 103-110,
2007. DOI: 10.1071/RD06101
9. Kondracki S, Górski K, Wysokińska A, Jóźwik I: Correlation of
ejaculate parameters and sperm morphology with the ejaculate volume
of Pietrain boars. Bulg J Agric Sci, 20, 721-727, 2014.
10. Holt WV, Hernandez M, Warrell L, Satake N: The long and the short
of sperm selection in vitro and in vivo: Swim-up techniques select for the
longer and faster swimming mammalian sperm. J Evol Biol, 23, 598-608,
2010. DOI: 10.1111/j.1420-9101.2010.01935.x
11. De Jarnette JM, Saake RG, Barne J, Volger CJ: Accessory sperm:
Their importance to fertility and embryo quality and attempts to alter
their numbers in artificially inseminated cattle. J Anim Sci, 70, 484-491,
1992.
12. Chenoweth PJ: Genetic sperm defects. Theriogenology, 64, 457-468,
2005. DOI: 10.1016/j.theriogenology.2005.05.005
13. García-Vázquez FA, Hernández-Caravaca I, Yánez-Quintana
W, Matás C, Soriano-Úbeda C, Izquierdo-Rico MJ: Morphometry of
boar sperm head and agellum in semen backow after insemination.
Theriogenology, 84, 566-574, 2015. DOI: 10.1016/j.theriogenology.2015.04.011
14. Gil MC, García-Herreros M, Barón FJ, Aparicio IM, Santos AJ,
García-Marín LJ: Morphometry of porcine spermatozoa and its functional
significance in relation with the motility parameters in fresh semen.
Theriogenology, 71, 254-263, 2009. DOI: 10.1016/j.theriogenology.2008.07.007
15. Ciftci HB, Zülkadir U: The correlation between bull sperm head
dimensions and mitochondria helix length. J Anim Vet Adv, 9, 1169-1172,
2010. DOI: 10.3923/javaa.2010.1169.1172
16. Noorafshan A, Karbalay-Doust S: A simple method for unbiased
estimating of ejaculated sperm tail length in subject with normal
and abnormal sperm motility. Micron, 41, 95-99, 2010. DOI: 10.1016/j.
micron.2009.09.002
17. Wysokińska A, Kondracki S, Banaszewska D: Morphometrical
characteristics of spermatozoa in Polish Landrace boars with regard to
the number of spermatozoa in an ejaculate. Reprod Biol, 9, 271-282, 2009.
DOI: 10.1016/S1642-431X(12)60031-X
18. Alonso R, Cama JM, Rodriguez J: El cerdo. Editorial Félix Varela,
Vedado Ciudad de La Habana, Cuba, 2004.
19. Stratman FW, Self HL: Eect of semen volume and number of sperm
on fertility and embryo survival in artificially inseminated gilts. J Anim
Sci, 19, 1081-1088, 1960.
20. Kaeoket K, Persson E, Dalin AM: The inuence of pre- and post-
ovulatory insemination on sperm distribution in the oviduct, accessory
sperm to the zona pellucida, fertilization rate and embryo development in
sows. Anim Reprod Sci, 71, 239-248, 2002. DOI: 10.1016/S0378-4320(02)00230-0
21. Ordinance of the Minister of Agriculture and Rural Development:
Journal of Laws, No. 56, item 344, 15 February 2010. www.isap.sejm.gov.
pl, Accessed: 08.04.2010.
22. Swine Nutrition Requirements: The Kielanowski Institute Animal
Physiology and Nutrition, Polish Academy of Sciences. Omnitech-Press,
Warsaw, Poland (in Polish), 1993.
23. King GJ, Macpherson JW: A comparison of two methods for
boar semen collection. J Anim Sci, 36, 563-565, 1973.
24. Kondracki S, Iwanina M, Wysokińska A, Huszno M: Comparative
analysis of Duroc and Pietrain boar sperm morphology. Acta Vet Brno,
81, 195-199, 2012. DOI: 10.2754/avb201281020195
25. Blom E: The morphological estimation of the spermatozoa defects
of bull. II. The proposal of new classification of spermatozoa defects (in
Polish). Med Weter, 37, 239-242, 1981.
26. Kondracki S, Banaszewska D, Mielnicka C: The eect of age on the
morphometric sperm traits of domestic pigs. Cell Mol Biol Lett, 1, 3-13, 2005.
27. STATISTICA®: Data Analysis, Software System. Version 10 StatSoft Inc,
2012.
28. Jankeviciute N, Zilinskas H: Inuence of some factors on semen
quality of dierent breeds of boars. Vet Med Zoot, 19, 15-19, 2002.
29. Banaszewska D, Kondracki S: An assessment of the breeding
maturity of insemination boars based on ejaculate quality changes. Folia
Biol, 60, 151-162, 2012. DOI: 10.3409/fb60_34.151162
30. Clark SG, Schaeer DJ, Althouse GC: B-mode ultrasonographic of
paired testicular diameter of mature boars in relation to average total
sperm numbers. Theriogenology, 60, 1011-1023, 2003. DOI: 10.1016/
S0093-691X(03)00127-4
31. Kula K, Walczak-Jędrzejowska R, Słowikowska-Hilczer J, Oszukowska
E: Estradiol enhances the stimulatory eect of FSH on testicular maturation
and contributes to precocious initiation of spermatogenesis. Mol Cell
Endocrinol, 178, 89-97, 2001. DOI: 10.1016/S0303-7207(01)00415-4
32. Oliveira CA, Carnes K, Franca LR, Hess RA: Infertility and testicular
atrophy in the antiestrogen-treated adult male rat. Biol Reprod, 72, 214-
220, 2001. DOI: 10.1095/biolreprod65.3.913
33. Kuster CE, Althouse GC: The fecundity of porcine semen stored for
2 to 6 days in AndrohepR and X-cellTM extenders. Theriogenology, 52, 365-
376, 1999. DOI: 10.1016/S0093-691x(99)00135-1
34. Shipley C: Breeding soundness examination of the boar. J Swine
Health Prod, 7, 117-120, 1999.
35. Šerniene L, Riškeviciene V, Banys A, Žilinskas H: Eects of age and
season on sperm qualitative parameters in Lithuanian White and Pietrain
boars. Vet Med Zoot, 17, 1-5, 2002.
36. Rutllant J, Pommer AC, Meyers SA: Osmotic tolerance limits and
properties of rhesus monkey (Macaca mulatta) spermatozoa. J Androl,
24, 534-541, 2003. DOI: 10.1002/j.1939-4640.2003.tb02705.x
37. Kondracki S, Wysokińska A, Iwanina M, Banaszewska D, Sitarz D:
Eect of sperm concentration in an ejaculate on morphometric traits of
spermatozoa in Duroc boars. Pol J Vet Sci, 14, 35-40, 2011. DOI: 10.2478/
v10181-011-0005-z
38. Kondracki S, Banaszewska D, Bajena M, Komorowska K,
Kowalewski D: Correlation of frequency of spermatozoa morphological
alterations with sperm concentration in ejaculates of Polish Landrace
boars. Acta Vet Beograd, 63, 513-524, 2013. DOI: 10.2298/AVB1306513K
39. Smital J: Eects inuencing boar semen. Anim Reprod Sci, 110, 335-
346, 2009. DOI: 10.1016/j.anireprosci.2008.01.024
40. Katz DF, Drobnis EZ: Analysis and interpretation of the forces
generated by spermatozoa. In, Bavister BD, Cummins J, Roldan ERS, Norwell
MA (Eds): Fertilization in Mammals. 125-137, Serono Symposia, 1990.
41. Lüpold S, Calhim S, Immler S: Sperm morphology and sperm
velocity in passerine birds. Proc Biol Sci, 276, 1175-1181, 2009. DOI:
10.1098/rspb.2008.1645
42. Bierła JB, Giżejewski Z, Leigh CM, Ekwall H, Söderquist L,
Rodriguez-Martinez H, Zalewski K, Breed WG: Sperm morphology of
the Eurasian beaver Castor fiber: an example of a species of rodent with
highly derived and pleiomorphic sperm populations. J Morphol, 268,
683-689, 2007. DOI: 10.1002/jmor.10544
43. Marmor D, Grob-Menendez F: Male infertility due to asthenozoo-
spermia and agellar anomaly: detection in routine semen analysis. Int
J Androl, 14, 108-116, 1991. DOI: 10.1111/j.1365-2605.1991.tb01072.x
44. Levitan DR: Sperm velocity and longevity trade o each other and
inuence fertilization in the sea urchin Lytechinus variegates. Proc R Soc
Lond, 267, 531-534, 2000. DOI: 10.1098/rspb.2000.1032
45. Burness G, Casselman SJ, Schulte-Hostedde AJ, Moyes CD,
Montgomerie R: Sperm swimming speed and energetics vary with
sperm competition risk in bluegill (Lepomis macrochirus). Behav Ecol
Sociobiol, 56, 65-70, 2004. DOI: 10.1007/s00265-003-0752-7
46. Rijsselaere T, Soom A, Hoack G, Meas D, Kruif A: Automated
sperm morphometry and morphology analysis of canine semen by the
501
Hamilton-Thorne analyser. Theriogenology, 62, 1292-1306, 2004. DOI:
10.1016/j.theriogenology.2004.01.005
47. Sailer BL, Jost LK, Evenson DP: Bull sperm head morphometry
related to abnormal chromatin structure and fertility. Cytometry, 24, 167-
173, 1996. DOI: 10.1002/(SICI)1097-0320(19960601)24:2<167::AID-CYTO9
>3.0.CO;2-G
48. Ostermeier GC, Sargeant GA, Yandell BS, Evenson DP, Parrish JJ:
Relationship of bull fertility to sperm nuclear shape. J Androl, 22, 595-603,
2001.
49. Evenson DP, Wixon R: Clinical aspects of sperm DNA fragmentation
detection and male infertility. Theriogenology, 65, 979-991, 2006. DOI:
10.1016/j.theriogenology.2005.09.011
50. Casey PJ, Gravance CG, Davis RO, Chabot DD, Liu IKM: Morphometric
dierences in sperm head dimensions of fertile and subfertile stallions.
Theriogenology, 47, 575-582, 1997. DOI: 10.1016/S0093-691X(97)00015-0
51. Hirai M, Boersma A, Hoeich A, Wolf E, Föll J, Aumüller R, Braun
AJ: Objectively measured sperm motility and sperm head morphometry in
boars (Sus scrofa): Relation to fertility and seminal plasma growth factors.
J Androl, 22, 104-110, 2001.
52. Villalobos DG, Quintero-Moreno A, López-Brea JJG, Esteso MC,
Fernández-Santos MR, Rubio-Guillén J, Silva WM, Marval YG, Atencio
GL, Bohórquez CL: Caracterización morfométrica de la cabeza del
espermatozoide porcinomediante análisis computarizado (Resultados
Preliminares). Revta Cient FCV-LUZ, 18, 570-577, 2008.
53. Malo AF, Gomendio M, Garde J, Lang-Lenton B, Soler AJ, Roldan
ERS: Sperm design and function. Biol Lett, 22, 246-249, 2006. DOI:
10.1098/rsbl.2006.0449
54. Helfenstein F, Podevin M, Richner H: Sperm morphology, swimming
velocity, and longevity in the house sparrow Passer domesticus. Behav Ecol
Sociobiol, 64, 557-565, 2010. DOI: 10.1007/s00265-009-0871-x
55. Arruda RP, Ball BA, Gravance CG, Garcia AR, Liu IKM: Eects of
extenders and cryoprotectants on stallion sperm head morphometry.
Theriogenology, 58, 253-256, 2002. DOI: 10.1016/S0093-691X(02)00858-0
56. Hidalgo M, Rodriguez I, Dorado JM: The eect of cryopreservation
on sperm head morphometry in Florida male goat related to sperm
freezability. Anim Reprod Sci, 100, 61-72, 2007. DOI: 10.1016/j.anireprosci.
2006.07.003
57. Gravance CG, Liu IKM, Davis RO, Hughs JP, Casey PJ: Quantification
of normal stallion sperm-head morphometry. J Reprod Fertil, 108, 41-46,
1996. DOI: 10.1530/jrf.0.1080041
58. De Paz P, Mata-Campuzano M, Tizado EJ, Álvarez M, Álvarez-
Rodríguez M, Herraez P, Anel L: The relationship between ram sperm
head morphometry and fertility depends on the procedures of acquisition
and analysis used. Theriogenology, 76, 1313-1325, 2011. DOI: 10.1016/j.
theriogenology.2011.05.038
59. Kot MC, Handel MA: Binding of morphologically abnormal sperm
to mouse egg zonae pellucidae in vitro. Gamete Res, 18, 57-66, 1987. DOI:
10.1002/mrd.1120180107
60. Purwantara B, Arifiantini RI, Riyadhi M: Sperm morphological
assessments of Friesian Holstein bull semen collected from Tyree artificial
insemination center in Indonesia. J Indonesian Trop Anim Agric, 35, 89-94,
2010.
61. Wysokińska A, Kondracki S: Assessment of sexual activity levels
and their association with ejaculate parameters in two-breed hybrids and
purebred Duroc and Pietrain boars. Ann Anim Sci, 14, 559-571, 2014. DOI:
10.2478/aoas-2014-0030
62. Boersma AA, Braun J, Stolla R: Inuence of random factors and
two dierent staining procedures on computer-assisted sperm head
morphometry in bulls. Reprod Domest Anim, 34, 77-82, 1999. DOI: 10.1111/
j.1439-0531.1999.tb01387.x
63. Bonet S: Immature and aberrant spermatozoa in the ejaculate of
Sus domesticus. Anim Reprod Sci, 22, 67-80, 1990. DOI: 10.1016/0378-
4320(90)90039-I
64. Hallap T, Nagy S, Haard M, Jaakma U, Johannisson A, Rodriguez-
Martinez H: Sperm chromatin stability in frozen-thawed semen is
maintained over age in AI bulls. Theriogenology, 63, 1752-1763, 2005. DOI:
10.1016/j.theriogenology.2004.08.001
65. Makhzoomi A, Lundeheim N, Haard M, Rodriguez-Martinez H:
Sperm morphology and fertility of progeny-tested AI Swedish dairy bulls.
Theriogenology, 70, 682-691, 2008. DOI: 10.1016/j.theriogenology.2008.04.049
66. Sarder MJU: Effects of age, body weight, body condition and
scrotal circumference on sperm abnormalities of bulls used for artificial
insemination (AI) programme in Bangladesh. Univ J Zool Rajshahi Univ, 27,
73-78, 2008. DOI: 10.3329/ujzru.v26i0.706
67. Pruneda A, Pinart E, Briz DM, Sancho S, Garcia-Gil N, Badia E,
Kádár E, Bassols J, Bussalleu E, Yeste M, Bonet S: Eects of a high
semen-collection frequency on the quality of sperm from ejaculates and
from six epididymal regions in boars. Theriogenology, 63, 2219-2232,
2005. DOI: 10.1016/j.theriogenology.2004.01.005
68. Herman H, Mitchell JR, Doak GA: Evaluation of semen-morphology.
In, Herman HA, Mitchell JR, Doak GA (Eds): The Artificial Insemination
and Embryo Transfer of Dairy and Beef Cattle. 8th ed., 87-92, Interstate
Publishers, Dauville, 1994.
69. Martin-Rillo S, Martinez E, Garcia C, Artiga C, De Alba C: Boar
semen evaluation in practice. Reprod Domest Anim, 31, 519-526, 1996.
70. Soderquist L, Janson L, Larsson K, Einarsson S: Sperm morphology
and fertility in A. I. bulls. J Vet Med A, 38, 534-543. 1991. DOI: 10.1111/
j.1439-0442.1991.tb01045.x
GÓRSKI, KONDRACKI
WYSOKIŃSKA, NAZARUK
... Several researchers have studied sperm characteristics to determine their correlations with fertility traits (Górski et al., 2016;Tremoen et al., 2018). The parameters used to define the fertility of the sow are pregnancy rate and litter size variables, such as the number of piglets born alive (Broekhuijse et al., 2012) and litter weight at birth (Wientjes et al., 2013). ...
Article
The semen movement and sperm head size patterns of boar ejaculates were analyzed using computer‐assisted semen analysis (CASA)‐Mot and ‐Morph systems. The aim of the present study was to compare morphometric and kinematics variables from boars and to determine the relationship with sow fertility variables related to litter size. The females were from maternal crossing schemes such as the continuous 3‐generation cross between York (Y), Landrace (L), and Pietrain (P) hybrid sows and Pietrain boars. Semen samples were collected from 11 sexually mature boars from two sire lines. Samples were analyzed using the ISAS®v1 system to evaluate eight kinematic variables of sperm velocity, progressiveness and undulations. Four morphometric parameters of sperm head size (length, width, area, and perimeter) were analyzed. Bayesian analysis revealed relevant differences in four kinematic variables (VSL, LIN, STR, and WOB) between sire lines, with a probability of relevance (PR) of 0.79‐0.91, and Pietrain boars were associated with higher progressive motility compared with Duroc x Pietrain boars. Moreover, there were relevant differences in all morphometric variables (PR = 0.82‐0.85) between sire lines. The dam line Y‐L‐50 (½ Y x ½ L) had higher total born per litter and piglets born alive, and YLP‐75 (1/8 Y x 1/8 L x 3/4 P) was associated with higher values of litter weight at birth (highest posterior density region at 95% = 9.92, 16.41 kg). There are relevant differences in kinematic variables between the assessed sire lines and the differences in morphometric and litter size variables were also relevant. The York‐Landrace hybrid sows had higher total born per litter and piglets born alive, and there were relevant differences when compared with YLP‐50 (¼ York x ¼ Landrace x ½ Pietrain). Differences in kinematic and morphometric variables between sire and dam lines related to fertility need to be further studied.
... Some studies have described a correlation between the fertility of males used for artificial insemination (AI) and sperm morphometry [12], and head size has been associated with factors predisposing fertility [16]. Other authors refer to an association between the head size and shape of the spermatozoa and semen or ejaculate variables [17][18][19]. The total spermatozoa in the ejaculate have been associated with the morphometric variables of spermatozoa: ejaculates with a low sperm concentration have smaller, shorter, and narrower head sizes and a smaller head area than those of ejaculates with a high sperm count [8]. ...
Article
Full-text available
The aim of the study was to compare the morphometric features of sperm head size and shape from the Pietrain line and the Duroc × Pietrain boar crossbred terminal lines, and to evaluate their relationship with reproductive success after artificial insemination of sows produced from crossbreeding the York, Landrace and Pietrain breeds. Semen samples were collected from 11 sexually mature boars. Only ejaculates with greater than 70% motility rate and < 15% of abnormal sperm were used for artificial inseminations (AI) and included in the study. Samples were analyzed using an ISAS®v1 computer-assisted sperm analysis system for eight morphometric parameters of head shape and size (CASA-Morph). Sub-populations of morphometric ejaculates were characterized using multivariate procedures, such as principal component (PC) analysis and clustering methods (k-means model). Four different ejaculate sub-populations were identified from two PCs that involved the head shape and size of the spermatozoa. The discriminant ability of the different morphometric sperm variables to predict sow litter size was analyzed using a receiver operating characteristics (ROC) curve analysis. Sperm head length, ellipticity, elongation, and regularity showed significant predictive capacity on litter size (0.59, 0.59, 0.60, and 0.56 area under curve (AUC), respectively). The morphometric sperm sub-populations were not related to sow litter size.
... This means that the semen quality of males used for artificial insemination is of particular importance. The suitability of boars for insemination depends on the level of libido (Xing et al., 2009;Kondracki et al., 2013) and on the quantity and quality of semen produced (Górski et al., 2016). Male fertility also depends on sperm morphology. ...
Article
Full-text available
The aim of the study was to determine the dependence of semen quality, frequency of sperm defects, and sperm dimensions and shape on sperm concentration in ejaculates of Large White and Landrace boars. A total of 648 ejaculates collected from 31 Large White and 30 Landrace boars were divided into three groups according to the criterion of sperm concentration. The physical characteristics of all ejaculates were determined, and morphological and morphometric examination of spermatozoa was performed. The characteristics of the ejaculates, frequency of sperm defects, and dimensions and shape of spermatozoa were shown to depend on the sperm concentration. Ejaculates with a high sperm concentration contain a large number of sperm, but have a smaller volume than ejaculates with a lower sperm concentration. Sperm from ejaculates with the lowest sperm concentration have larger dimensions than sperm from ejaculates with intermediate and high sperm concentrations. This is expressed in a larger head area and perimeter and in greater total sperm length. The dependence of the ejaculate characteristics and the size and shape of sperm on the sperm concentration is influenced by the breed. In the ejaculates of Landrace boars, these relationships are more pronounced than in Large White boars. An increased sperm concentration reduces the occurrence of the Dag defect but promotes the occurrence of sperm with a proximal droplet, a pseudodroplet, or a distal droplet.
... The shape of the head has been reported to be important for fertilization (Górski, Kondracki, Wysokińska, & Nazaruk, 2016). ...
Chapter
Full-text available
INTRODUCTION Animals used in research and biological studies designed according to scientific rules are called experimental animals or laboratory animals. The reasons why these animals are preferred as experimental animals are; ease of cultivation, ease of performing complex genetic applications, short pregnancy duration and sexual cycles, easy feeding and care, no need for large cultivation areas and sufficient knowledge gathered over many years. According to the International Laboratory Animals Committee; 40% to 80% of the preferred laboratory animals were reported to be mice (Akman, 2007). Laboratory animals can be listed as follows according to the frequency of experiments. 1. Mice 2. Rats 3. Rabbit 4. Guinea pigs The male reproductive system and production, nutrition and storage of haploid male sex cells is responsible for the production and secretion of male sex hormones. Male reproductive system organs include effluent channels that transmit these cells from testes that express gonad cells and secrete androgens, of the tubuli recti, rete testis, ductuli efferentes, ductus epididymis, ductus deferens, ductus ejaculatorius and urethra; and the prostate gland, seminal vesicle and bulbourethral glands and external genital penis (Bernal, Aya, De Jesus-Ayson, & Garcia, 2015).
... The morphological characteristics of spermatozoa may be influenced by the rate of sperm production in the testicular tissue and thus the number of sperm stored in the epididymis and released in the ejaculate (Hossain et al. 1997;Silva et al. 2012). The dimensions and shape of sperm have been shown to be correlated with ejaculate characteristics and male fertility (Rijsselaere et al. 2004;Ramm et al. 2014;Górski et al. 2016). Even morphologically normal sperm cells differ in shape, which may affect the speed with which they reach the ovum (Banaszewska et al. 2009). ...
Article
Full-text available
Abstract. The aim of this study was to evaluate inter-bred and intra-breed variation in ejaculates and the morphology, dimensions and shape of spermatozoa of boars used for artificial insemination. The results obtained from this study suggested that there is relatively high intraand inter-breed variation in the basic characteristics of ejaculates. The ejaculates of the Landrace and Large White boars have markedly greater volume than those of the Duroc boars or the Duroc × Pietrain crossbreds, while the ejaculates of the Landrace boars contain more sperm cells than those of boars of other breeds. The spermatozoa of the crossbred boars exhibit lower motility than the sperm of other breeds. Results revealed that factors other than breed have a much greater influence on the frequency of morphological sperm defects. The morphometric dimensions of sperm cells are characterized by low intra-breed variation and relatively high inter-breed variation. The results showed that the sperm of Landrace boars had the largest head area. The spermatozoa of the Large White boars had the shortest heads and their tails were significantly shorter than those of the sperm of other breeds.
... Semen quality can be evaluated by examining sperm morphology, which makes it possible to assess whether the sperm structure is normal and to specify the type of morphological anomalies present (Górski et al., 2017). Ejaculates of males vary in terms of the frequency of sperm with abnormal morphology (Górski et al., 2016;Pinart et al., 1998;Ruiz-Sanchez et al., 2006). The suitability of semen for artificial insemination may be influenced by the dimensions and shape of the sperm (Gage and Morrow, 2003), as correlations have been demonstrated between sperm dimensions and male fertility (Casey et al., 1997). ...
Article
Full-text available
Reproductive efficiency in pigs is largely dependent on the fertility of the boar. Boars used at insemination stations should produce a large amount of semen with high fertilization capacity. The sperm count influences the conception rate and the number of insemination doses produced. The aim of this study was to evaluate the morphological and morphometric characteristics of boars of the Hypor breed in relation to the total sperm count in the ejaculate. An analysis was performed of 120 ejaculates collected from 12 Hypor boars used at three insemination stations. The ejaculate sperm count was found to affect the morphometric characteristics of spermatozoa from boars. In the ejaculates with the lowest sperm count the spermatozoa heads were significantly shorter and narrower and had a smaller surface area. The sperm from ejaculates with the lowest sperm count had relatively small head dimensions in relation to the tail length and total sperm length. In the ejaculates with the most sperm cells, the proportion of spermatozoa with major defects was significantly greater than in the ejaculates from other groups. In the ejaculates with the lowest sperm count the frequency of sperm with progressive motility was significantly lower. The fewest insemination doses can be prepared from these ejaculates.
Article
Full-text available
The aim of the study was to determine the relation between the semen quality, frequency of sperm defects, sperm dimensions and shape, and the ejaculate volume of Large White and Landrace boars. A total of 648 ejaculates collected from 31 Large White and 30 Landrace boars were divided into three groups according to the criterion of the ejaculate volume. In this study Landrace boars produced ejaculates with higher volume, sperm concentration, and total numbers of spermatozoa than Large White boars. Landrace boars also showed a lower frequency of sperm with morphological abnormalities (P < 0.05). Landrace boars sperm had larger heads, which were by 0.15 μm longer, and by a larger perimeter and area (P < 0.05). Landrace boar spermatozoa also had a longer flagellum and were generally larger and by 2.07 μm longer than Large White boar sperm (P < 0.05). Significant differences were also found in the shape of sperm of the two breeds (P < 0.05). Landrace boars sperm had more elongated heads, and the ratio of head size to flagellum length was lower than in Large White boars sperm (P < 0.05). Sperm from ejaculates with low volume had a shorter flagellum and a greater head length/flagellum length ratio than sperm from medium‐ and high‐volume ejaculates (P < 0.05).
Article
Full-text available
The aim of the study was to determine the relationship of sperm morphology with age of males, ejaculate concentration and volume, as well as with acrosin activity determined in sperm acrosome extracts. The study used manually collected ejaculates from 9 male arctic foxes, including 6 young males aged one year and 3 older males (between 3 and 5 years of age). All of the 39 ejaculates used in the study were classified as normal based on motility exceeding 70%. The ejaculates collected from the foxes were evaluated for volume, sperm concentration and frequency of morphological changes including primary and secondary defects. The spermiograms of the male arctic foxes were classified according to a six-grade subjective scale. In addition, acrosin activity was determined in the sperm acrosome extracts. The data were analysed using the criteria of male age, sperm concentration, ejaculate volume, and acrosin activity. The morphology of arctic fox spermatozoa was dependent on the age of the male. A greater number of morphologically altered spermatozoa tended to occur in the ejaculates of young foxes, which were in their first breeding season. In addition, statistical analysis revealed positive relationships between the frequency of morphological changes in sperm and their ejaculate concentration. In contrast, there were no significant correlations between the percentages of morphologically changed spermatozoa and the ejaculate volume and the content of acrosin, which is an indicator of acrosomal integrity. Semen quality is dependent on the number of sperm in ejaculate with morphological defects which prevent oocyte fertilization. Therefore, morphological assessment of semen, which covers both the number and type of morphological changes, is highly useful when selecting appropriate males for reproduction.
Article
Full-text available
The aim of this study was to evaluate the effect of the season of the year on the quality of Hypor boar semen and to determine the correlations between selected semen characteristics in particular seasons. Ejaculates from Hypor boars were analyzed for volume, sperm concentration, percentage of spermatozoa with normal motility, total number of spermatozoa, and the number of insemination doses per ejaculate. Microscopic slides were prepared from semen samples. Each sample was evaluated for the morphology of spermatozoa. Spermatozoa with normal morphology were counted, as well as those with both major and minor abnormalities. Spermatozoa were measured for morphometric traits. Ejaculates were grouped by the season of collection: winter, spring, summer, and autumn. Correlation coefficients were calculated between sperm morphometric traits and the concentration and total count of spermatozoa in ejaculates. In spring and winter, sperm concentrations are higher compared to ejaculates collected in summer and autumn. In spring and summer, ejaculates contain spermatozoa of greatest motility. In spring, sperm cells have largest head dimensions. In autumn, spermatozoa are smallest in terms of dimensions. Significant correlations were observed between sperm concentration and total number of sperm in ejaculates vs. morphometric dimensions of sperm heads in Hypor boars’ semen in the autumn, winter, and summer.
Article
Full-text available
Morphologically abnormal sperm in semen has been associated with the sub fertility and sterilityfor many years. This study assessed the sperm morphology of Friesian Holstein bull semen which wascollected from three Artificial Insemination centers in Indonesia. Total of 22 bulls were used in thisstudy; an ejaculate from each bull was examined. Three to four glass slides were prepared for each bullsample; a drop of semen was placed on each glass slide, smeared, and air-dried. The smeared sampleswere stained with carbolfuchsin-eosin (Williams stain). Morphological abnormality types were recordedfrom total of 500 spermatozoa. Results demonstrated that all 22 bulls had low sperm abnormality(<10%). Pearshaped was the most frequently type of sperm abnormality found in the samples(0.81±0.93%); while detached head was the lowest (0.01±0.04%).
Article
Full-text available
The aim of this study was to compare ejaculates of Duroc and Pietrain boars in terms of sperm morphology characteristics. Analysis was performed on 116 ejaculates collected from 6 Duroc boars and 9 Pietrain boars. The boars selected for examination were young and at the beginning of their reproductive utilization. Ejaculates were collected at monthly intervals over the period of 10 months. Microscopic slides were prepared immediately after collection of ejaculates. The slides were examined to assess the frequency of morphological abnormalities. Moreover, morphometric measurements were taken from 15 randomly selected morphologically normal spermatozoa. Also, conventional evaluation of ejaculates was made following methods used at Polish sow insemination centres. Differences were found in the dimensions and shape between Duroc and Pietrain spermatozoa. Pietrain spermatozoa were characterised by significantly smaller head perimeter compared with Duroc (P ≤ 0.01). Moreover, Pietrain spermatozoa tails were by 0.8 μm longer (P ≤ 0.01), and their total sperm length was greater by 0.5 μm compared to Duroc (P ≤ 0.05) sperm. The volume of Duroc ejaculates was lower but their sperm concentration was greater. The results of the present study contribute to scientific progress as they demonstrate differences in sperm size between boars of different breeds, which may be reflected in different reproductive performances of the boars.
Article
Full-text available
The present study was carried out to assess changes in sperm cell membrane integrity occurring during the storage of semen collected from genetically different domestic male pigs. The study was aimed at assessing differences in the course of changes in the integrity of cell membranes in spermatozoa produced by males with different degrees of genetic diversity (pure-bred males, two-breed hybrids and multi-breed crosses) and testing the usefulness of two methods of sperm cell membrane integrity evaluation, based on material collected from genetically different males. The experiments were conducted on 56 ejaculates collected from 28 domestic male pigs. The examination of sperm cell membrane integrity was performed three times for each ejaculate, i.e., after 1 h, after 24 h and after 48 h from collection. The preparations for analysing cell membrane integrity were made using two methods: the SYBR 14/PI method and the eosin-nigrosin method. It was found that both SYBR 14/PI and eosin-nigrosin staining methods make it possible to successfully assess the integrity of the plasma membrane of domestic pig sperm cells under in vitro conditions. Hybrid pig spermatozoa, especially those from multi-breed crosses, better retain the integrity of their plasmalemmas than the spermatozoa of pure-bred boars. The ejaculates of Hypor cross-breed boars assessed after 1, 24 and 48 h of storage contain more spermatozoa with intact cell membranes than the ejaculates of pure-bred Duroc and Pietrain boars. The ejaculates of Hypor boars also show fewer decaying spermatozoa than those produced by pure-bred boars.
Article
Full-text available
The aim of the present study was to analyse sexual activity levels of two purebred boars (Pietrain and Duroc) in comparison with two-breed hybrid boars (Duroc female x Pietrain male and Pietrain female x x Duroc male) and to assess the relationship between the ejaculate parameters and the sexual activity of the animals. The experimental material was constituted by 20 boars. Sexual activity measurements were performed in 4 different collection periods for each boar. The first libido analysis was carried out during the first week of insemination use, followed by the next analyses after 3, 6 and 9 months of service. In parallel to the sexual activity analyses, ejaculates were collected to investigate ejaculatory efficiency, physical characteristics of the ejaculates and sperm morphology. It has been shown that the characteristics of sexual activity parameters are affected by the breed of the boar and the crossbreeding variant. Two-breed sires are quicker to leap onto the phantom as compared with purebred boars. Duroc female x Pietrain male boars are characterized by a short period of time between phantom mounting and ejaculation initiation. On the other hand, they yield ejaculates for a much longer time than hybrid Pietrain female x Duroc male boars and purebred Duroc and Pietrain boars. Hybrid boar ejaculates contain more spermatozoa and can provide more insemination doses than ejaculates of purebred boars. Ejaculate parameters are chiefly correlated with ejaculation time and copulation duration. In our study the ejaculate parameters (ejaculate volume, sperm concentration and sperm motility) in purebred boars mainly depended on ejaculation time and total copulation duration, whereas in two-breed hybrids they were more affected by the length of the period between phantom mounting and the start of ejaculation.
Article
This article describes the procedure for conducting a breeding soundness examination in the boar, including collection of a history, examination of the genitalia, semen collection and evaluation, and suggestions for culling criteria.
Article
Once deposited in the female reproductive system, sperm begin their competition and undergo a selection to reach the site of fertilization. Little is known about the special characteristics of sperm that reach the oviduct and are able to fertilize, with even less information on the role of sperm dimension and shape in transport and fertilization. Here, we examine whether sperm morphometry could be involved in their journey within the uterus. For this purpose, sperm head dimension (length, width, area, and perimeter) and shape (shape factor, ellipticity, elongation, and regularity), and flagellum length were analyzed in the backflow at different times after insemination (0-15, 16-30, and 31-60 minutes). Sperm morphometry in the backflow was also analyzed taking into account the site of semen deposition (cervical vs. intrauterine). Finally, flagellum length was measured at the uterotubal junction. Sperm analyzed in the backflow were small (head and flagellum) with different head shapes compared with sperm observed in the dose before insemination. The site of deposition influenced head morphometry and tail size both being smaller in the backflow after cervical insemination compared with intrauterine insemination. Mean tail length of sperm collected in the backflow was smaller than that in the insemination dose and at the uterotubal junction. Overall, our results suggest that sperm size may be involved in sperm transport either because of environment or through sperm selection and competence on their way to encounter the female gamete. Copyright © 2015 Elsevier Inc. All rights reserved.
Article
The estrogen receptor-α (ERα) knockout mouse (αERKO) lacks ERα throughout development; therefore, an adult model for the study of estrogen effects in male mice was recently developed using the antiestrogen ICI 182,780. However, differences between species have been noted during immunostaining for ERα in the male tract as well as in response to treatments with antiestrogens. Therefore, we developed the antiestrogen model in the adult male rat to test, in another species, the hypothesis that estrogen regulates fluid reabsorption in efferent ductules. Estrogen receptor in the rat was blocked using ICI 182,780 for 100–150 days. Male Sprague-Dawley rats were treated weekly with s.c. injections of ICI 182,780 (10 mg) or castor oil (as control). The effects of ICI included testicular atrophy and infertility, similar to terminal effects in the αERKO male. Additionally, ICI induced dilations of the rete testis and efferent ductules and a reduction in the height of the ductule epithelium, which are changes similar to those in both αERKO and ICI-treated mice. One difference between species was a large variation in effects on the rat efferent ductule epithelium, including a transient increase in the number of periodic acid-Schiff-positive, lysosomal-like granules. These data confirm that estrogen is required for normal function of the efferent ductules and is essential for long-term fertility in the male rodent.