Effects of attapulgite dietary supplementation on sow performance in two commercial farms in Greece

Abstract

The present study investigated the effects of attapulgite supplementation in sow diets during gestation and lactation on sow performance. The study comprised two reproductive phases (cycles) in two commercial farrow to finish farms: Farm A (capacity: 550 sows) and Farm B (capacity: 220 sows). The treatment groups were: a) control group (CN): the sows were fed a common gestation or lactation diet; b) attapulgite group (AT): the sows were fed the CN diet supplemented with attapulgite at 0,7% level; c) attapulgite plus group (AT+): the sows were fed the CN diet supplemented with attapulgite (0.7%) and a mix of enzymes, live yeast and amino acids (0.1%), at a total of 0.8% level. Within each cycle the sows included per treatment were: 24 for Farm A; 12 for Farm B. Initially data were analyzed per cycle and per each farm. Data from sows that completed both cycles within each farm, were analyzed by repeated measures analysis. Regarding sow parameters, sow body weight loss during lactation tended to be greater in AT sows compared to CN sows during cycle 1 in Farm B and was greater in AT and AT+ than CN sows in Farm A that completed both cycles (P=0.063 and P=0.023, respectively). A greater litter size 24h postpartum was observed in favour of AT compared to CN group during cycle 1 in Farm A and in sows that completed both cycles in Farm A (P=0.001 and P= 0.011, respectively). Litter size at weaning was greater in sows from the AT group than CN during cycle 1 and 2 in Farm A, in cycle 1 in Farm B and in sows that completed both cycles in Farm A (P=0.004, P=0.037, P=0.037, and P=0.022, respectively). Piglet weight at weaning and average daily gain during lactation were greater in AT group than CN and AT+ in sows that completed both cycles in Farm A (P=0.049 and P=0.040 respectively). Notable similar effects, although not statistically significant, were also observed in Farm B. This field study suggests that attapulgite supplementation in sow diets can improve performance indexes. Further research should investigate the underlying mechanisms involved.

Full text

Journal of the Hellenic Veterinary Medical Society
Vol. 68, 2017
Effects of attapulgite dietary supplementation on
sow performance in two commercial farms in
Greece
KANOULAS V. Laboratory of Animal
Husbandry, Faculty of
Veterinary Medicine, School
of Health Sciences, Aristotle
University of Thessaloniki
PAPADOPOULOS G. Laboratory of Animal
Husbandry, Faculty of
Veterinary Medicine, School
of Health Sciences, Aristotle
University of Thessaloniki
ARSENOS G. Laboratory of Animal
Husbandry, Faculty of
Veterinary Medicine, School
of Health Sciences, Aristotle
University of Thessaloniki
TZIKA E. Clinic of Farm Animals,
Faculty of Veterinary
Medicine, School of Health
Sciences, Aristotle University
of Thessaloniki
FORTOMARIS P. Laboratory of Animal
Husbandry, Faculty of
Veterinary Medicine, School
of Health Sciences, Aristotle
University of Thessaloniki
http://dx.doi.org/10.12681/jhvms.15605
Copyright © 2017 V KANOULAS, GA PAPADOPOULOS, G
ARSENOS, ED TZIKA, P FORTOMARIS
To cite this article:
KANOULAS, PAPADOPOULOS, ARSENOS, TZIKA, & FORTOMARIS (2017). Effects of attapulgite dietary
supplementation on sow performance in two commercial farms in Greece. Journal of the Hellenic Veterinary Medical Society,
68, 193-204.
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Effects of attapulgite dietary supplementation on sow performance in
two commercial farms in Greece
Kanoulas V.1, Papadopoulos G.A.1, Arsenos G.1, Tzika E.D.2, Fortomaris P.1*
1Laboratory of Animal Husbandry, Faculty of Veterinary Medicine, School of Health Sciences, Aristotle University of
Thessaloniki, 54124, Thessaloniki, Greece
2Clinic of Farm Animals, Faculty of Veterinary Medicine, School of Health Sciences, Aristotle University of Thessaloniki,
54124, Thessaloniki, Greece
Μελέτη της επίδρασης της προσθήκης ατταπουλγίτη στα σιτηρέσια
χοιρομητέρων, στις αποδόσεις τους, σε δυο εμπορικές εκτροφές στην
Ελλάδα
Κανούλας Β.1, Παπαδόπουλος Γ.Α.1, Αρσένος Γ.1, Τζήκα Ε.Δ.2, Φορτομάρης Π.1*
1Εργαστήριο Ζωοτεχνίας, Τμήμα Κτηνιατρικής, Σχολή Επιστημών Υγείας, Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης, 54124, Θεσσαλονίκη,
Ελλάδα
2Κλινική Παραγωγικών Ζώων, Τμήμα Κτηνιατρικής, Σχολή Επιστημών Υγείας, Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης, 54124, Θεσσαλονίκη,
Ελλάδα
*Corresponding author: Paschalis Fortomaris,
Laboratory of Animal Husbandry, Faculty of Veterinary Medicine,
School of Health Sciences, Aristotle University of Thessaloniki,
54124, PO BOX 393, Thessaloniki, Greece,
fortomap@vet.auth.gr
Date of initial submission: 2.3.2016
Date of revised submission: 20.5.2016
Date of acceptance:1.6.2016
J HELLENIC VET MED SOC 2017, 68(2):193-204
ΠΕΚΕ 2017, 68(2): 193-204
ABSTRACT. The present study investigated the effects of attapulgite supplementation in sow diets during gestation
and lactation on sow performance. The study comprised two reproductive phases (cycles) in two commercial farrow
to nish farms: Farm A (capacity: 550 sows) and Farm B (capacity: 220 sows). The treatment groups were: a) control
group (CN): the sows were fed a common gestation or lactation diet; b) attapulgite group (AT): the sows were fed the
CN diet supplemented with attapulgite at 0,7% level; c) attapulgite plus group (AT+): the sows were fed the CN diet
supplemented with attapulgite (0.7%) and a mix of enzymes, live yeast and amino acids (0.1%), at a total of 0.8% level.
Within each cycle the sows included per treatment were: 24 for Farm A; 12 for Farm B. Initially data were analyzed
per cycle and per each farm. Data from sows that completed both cycles within each farm, were analyzed by repeated
Research article
Ερευνητικό άρθρο
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194
KANOULAS V., PAPADOPOULOS G.A., ARSENOS G., TZIKA E.D., FORTOMARIS P.
measures analysis. Regarding sow parameters, sow body weight loss during lactation tended to be greater in AT sows com-
pared to CN sows during cycle 1 in Farm B and was greater in AT and AT+ than CN sows in Farm A that completed both
cycles (P=0.063 and P=0.023, respectively). A greater litter size 24h postpartum was observed in favour of AT compared
to CN group during cycle 1 in Farm A and in sows that completed both cycles in Farm A (P=0.001 and P= 0.011, respec-
tively). Litter size at weaning was greater in sows from the AT group than CN during cycle 1 and 2 in Farm A, in cycle 1
in Farm B and in sows that completed both cycles in Farm A (P=0.004, P=0.037, P=0.037, and P=0.022, respectively).
Piglet weight at weaning and average daily gain during lactation were greater in AT group than CN and AT+ in sows that
completed both cycles in Farm A (P=0.049 and P=0.040 respectively). Notable similar effects, although not statistically
signicant, were also observed in Farm B. This eld study suggests that attapulgite supplementation in sow diets can
improve performance indexes. Further research should investigate the underlying mechanisms involved.
Keywords: Sows, Attapulgite (Palygorskite), Reproduction Performance
ΠΕΡΙΛΗΨΗ. Στόχος της παρούσας μελέτης ήταν η διερεύνηση της επίδρασης της προσθήκης ατταπουλγίτη στα
σιτηρέσια των χοιρομητέρων, στις αποδόσεις τους κατά τη διάρκεια της κυοφορίας και της γαλουχίας. Η μελέτη
συμπεριέλαβε δύο συνεχείς αναπαραγωγικούς κύκλους σε δύο εμπορικές εκτροφές: Εκτροφή Α (δυναμικότητας 550 χοι-
ρομητέρων), Εκτροφή Β (δυναμικότητας 220 χοιρομητέρων). Οι πειραματικές ομάδες ήταν: α) ομάδα μάρτυρας (CN):
οι χοιρομητέρες κατανάλωναν το σύνηθες σιτηρέσιο κυοφορίας και γαλουχίας, β) ομάδα ατταπουλγίτη (ΑΤ): οι χοιρο-
μητέρες κατανάλωναν το σιτηρέσιο της ομάδας CN με επιπλέον 0,7% προϊόντος ατταπουλγίτη και γ) ομάδα σύνθετου
ατταπουλγίτη (ΑΤ+): οι χοιρομητέρες κατανάλωναν το σιτηρέσιο της ομάδας CN με επιπλέον 0,7% ατταπουλγίτη και
ενός μίγματος αποτελούμενου από ένζυμα, ζύμες και αμινοξέα (0,1%), σε σύνολο προσθήκης το 0,8%. Ο αριθμός των
χοιρομητέρων σε κάθε πειραματική ομάδα και ανά κύκλο ήταν: 24 για την Εκτροφή Α, 12 για την Εκτροφή Β. Αρχικά,
τα πειραματικά δεδομένα επεξεργάστηκαν στατιστικά για κάθε κύκλο και για κάθε εκτροφή χωριστά. Στη συνέχεια,
η ανάλυση δεδομένων των χοιρομητέρων που ολοκλήρωσαν και τους 2 κύκλους στις 2 εκτροφές έγινε με ανάλυση
διακύμανσης με επαναλαμβανόμενες μετρήσεις. Η απώλεια σωματικού βάρους των χοιρομητέρων κατά τη διάρκεια
της γαλουχίας, ήταν οριακά υψηλότερη στην ομάδα ΑΤ σε σχέση με την ομάδα CN κατά τη διάρκεια του πρώτου
αναπαραγωγικού κύκλου στην Εκτροφή Β και υψηλότερη στις ομάδες ΑΤ και ΑΤ+ σε σχέση με την ομάδα CN στις
χοιρομητέρες που ολοκλήρωσαν και τους 2 αναπαραγωγικούς κύκλους στην Εκτροφή Α (P=0.063 και P=0.023, αντίστοι-
χα). Το μέγεθος της τοκετοομάδας 24 ώρες μετά τον τοκετό ήταν υψηλότερο στην ομάδα ΑΤ σε σχέση με την ομάδα CN
κατά τον πρώτο κύκλο στην Εκτροφή Α καθώς και στις χοιρομητέρες που ολοκλήρωσαν τους 2 κύκλους στην Εκτροφή
Α (P=0.001 και P=0.011, αντίστοιχα). Το μέγεθος της τοκετοομάδας στον απογαλακτισμό ήταν υψηλότερο στην ομάδα
ΑΤ σε σχέση με την ομάδα CN στον πρώτο και δεύτερο κύκλο στην Εκτροφή Α, στον πρώτο κύκλο στην Εκτροφή Β και
στις χοιρομητέρες που ολοκλήρωσαν τους 2 αναπαραγωγικούς κύκλους στην Εκτροφή Α (P=0.004, P=0.037, P=0.037 και
P=0.022, αντίστοιχα). Το βάρος των χοιριδίων στον απογαλακτισμό και η μέση ημερήσια αύξηση των χοιριδίων κατά τη
διάρκεια της γαλουχίας ήταν υψηλότερα στην ομάδα ΑΤ σε σχέση με τις ομάδες CN και ΑΤ+ καθώς και στις χοιρομητέρες
που ολοκλήρωσαν τους 2 κύκλους στην Εκτροφή Α (P=0.049 και P=0.040, αντίστοιχα). Αξίζει να σημειωθεί ότι παρόμοια
αποτελέσματα παρατηρήθηκαν και για την Εκτροφή Β, χωρίς όμως αυτά να είναι στατιστικά σημαντικά. Η παρούσα
μελέτη, που διενεργήθηκε σε επίπεδο εκτροφής, έδειξε πως η χορήγηση του ατταπουλγίτη στα σιτηρέσια χοιρομητέρων
είναι δυνατό να βελτιώσει τους αναπαραγωγικούς δείκτες. Ωστόσο, κρίνεται αναγκαία περαιτέρω έρευνα για τη
διερεύνηση των μηχανισμών που σχετίζονται με τις ευεργετικές επιδράσεις του ατταπουλγίτη στις χοιρομητέρες.
Λέξεις ευρετηρίασης: Χοιρομητέρες, Ατταπουλγίτης (Παλυγκορσκίτης), Αναπαραγωγική Ικανότητα
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ΚΑΝΟΎΛΑΣ Β., ΠΑΠΑΔΟΠΟΎΛΟΣ Γ.Α., ΑΡΣΕΝΟΣ Γ., ΤΖΗΚΑ Ε.Δ., ΦΟΡΤΟΜΑΡΗΣ Π.
195
proposed as a plausible mechanism after clinoptilo-
lite supplementation in sows (Kyriakis et al., 2002).
It should be noted that the information of the dietary
inclusion of attapulgite in sows is scarce. Hence, the
objective of the present study was to evaluate the
effects of attapulgite dietary supplementation on sow
performance during gestation and lactation periods.
MATERIALS AND METHODS
The experimental procedures in this study
received approval from the Research Committee
of the Aristotle University of Thessaloniki, Greece
(Protocol No 67555/ Code 85152) and followed
the guidelines of Directive 2010/63/EU for animal
experiments.
Study Farms
The present study was performed under eld condi-
tions. Two farms were selected, based on the follow-
ing criteria: number of sows under production and
geographical distribution. The farms were situated
in different geographical parts of Greece: Farm A
in Fillipiada of Preveza prefecture (capacity of 550
sows) and Farm B in Megalochori of Trikala pre-
fecture (capacity of 220 sows). The study started
during the same period in both farms. Both farms
implemented vaccination protocols in the reproduc-
tive population against Aujersky’s virus, Porcine
Respiratory Reproductive Syndrome virus, Parvo
virus, Esypelothrix Rhusiopathiae and E. coli.
Treatments
The treatment groups were: a) control group (CN):
The sows were fed a common diet according to their
reproductive stage (gestation-lactation); b) attapulg-
ite group (AT): The sows were fed the common diet
according to their reproductive stage, which was
supplemented with attapulgite at 0.7% level, which
was the recommended level by the producing compa-
ny (Optify®, Geohellas S.A., Athens, Greece) and c)
attapulgite plus group (AT+): The sows were fed the
common diet according to their reproductive stage,
which was supplemented with attapulgite (0.7%)
and a mix of vitamins, trace elements, enzymes,
live yeast and amino acids (0.1%), at a total of 0.8%
level (Ultrafed®, Geohellas S.A., Athens, Greece).
INTRODUCTION
It is well established that sows during lactation enter a
catabolic state, in which feed intake is often not suf-
cient to fulll the energy demands for maintenance and
milk production (Eissen et al., 2003). To achieve suf-
cient milk production and support the growth of the prog-
eny, sows catabolize their body reserves, as an energy
source for milk (Noblet et al., 1998). However, extreme
body weight losses during lactation, can negatively inu-
ence farrowing rate and litter size in subsequent parity
(Prunier et al., 2003; Schenkel et al., 2010). Thus, it is
essential to improve nutrient utilization in sows during
gestation and lactation by nutritional means.
Clays represent a category of supplements that have
been applied in pig nutrition. Clays are naturally
occurring materials, having as basic constituent ne-
grained minerals with specic structures of porous
aluminosilicate-layers (Guggenheim and Martin,
1995; Papaioannou et al., 2005; Williams et al.,
2009). Due to their absorptive capacity, supplementa-
tion of clays (e.g. smectite, kaolinite, clinoptilolite)
in weaned pig diets ameliorated diarrhea incidence
after experimental challenge with enterotoxigenic
E. coli (Song et al., 2012). In particular, attapulgite
(also referred as palygorskite) is a clay mineral that
belongs to the group of hormites and is character-
ized by its elongated shape (Murray, 2000), in an
arrangement of blocks separated by parallel channels
composed by two layers of SiO2 tetrahedral enclos-
ing a layer of MgO octahedral (Alvarez et al., 2011).
This shape is responsible for its high absorption
capacity (Murray, 2000). A thermal or acid treat-
ment enhances its sorptive properties and surface
area (Alvarez et al., 2011). Dietary supplementation
with 2000 mg/kg palygorskite improved growth
performance and reduced the incidence of diarrhea
in weaned piglets (Zhang et al., 2013). In lactating
cows, palygorskite supplementation at levels up to 10
kg/t, improved cow milk yield, increased milk pro-
tein yield and decreased milk colony forming units
(Bampidis et al., 2014). The latter authors attributed
partly the positive effects of attapulgite in cows to
the toxin binding effect of the material. However,
the effects of attapulgite on a lactating animal could
not only be attributed to the toxin binding effect, but
also to plausible improvement of nutrient utilization.
For example, a sparing effect of energy and nutrients
for a better farrowing and lactation performance was
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rooms approximately 4 days before the expected far-
rowing date. Transfer of sows to the farrowing crates
in farm B was performed 3 days before the expected
farrowing date. Farrowing induction was not regular-
ly practiced in any of the two farms, unless a sow has
exceeded by one day of the expected farrowing day.
Cross fostering of piglets took place within 24h post-
partum and was allowed only within the same treat-
ment in both farms. Regular piglet husbandry pro-
cedures (teeth clipping, iron injection, tail docking
and castration of male piglets) took place between
the second and fourth day postpartum in both farms.
Weaning took place at 21 days postpartum in Farm
A and in 28 days postpartum in Farm B. Restricted
feeding of sows was followed as a regular practice
in both farms. Specically, in Farm A during gesta-
tion the daily feed allowance was adjusted from after
insemination to 90th day of gestation at 2.5 kg/day,
and from 90th day of gestation to the day of transfer
to farrowing room at 2.8 kg/day. In Farm B the daily
feed allowance was adjusted from after insemination
to 30th day of gestation at 3.0 kg/day, from the 31st
day to 85th day of gestation at 2.3 kg/day, and from
86th day of gestation to the day of transfer to far-
rowing room at 2.6 kg/day. At placement in the far-
rowing crate, the diet of sows shifted to the lactation
diet. In Farm A, during lactation sows were fed at a
level of 2kg at farrowing plus 400g/ piglet, divided
over two meals per day. The sows were fed on an
A detailed mineralogical characterization, chemical
composition and other properties of the material used
in here is described in a previous publication of our
research group (Chalvatzi et al., 2014).
Experimental Design
The aim of the trial was to implement a sufcient
number of clinically healthy sows and to study the
effects of supplementation of attapulgite on sow diets
for 2 consecutive reproductive phases (cycles). To
achieve the desired number of sows, a higher number
of sows was allocated to the treatments at the onset
of each reproductive cycle, in order to cover the
unpredicted factors that could cause the exclusion
of experimental animals, e.g. return to oestrus after
insemination, culling due to lameness etc. Thus, a
total of 24 sows in Farm A and 12 sows in Farm B
were included per treatment for both cycles. It should
be noted that the sows that completed both experi-
mental phases (cycles) were in Farm A, 15 sows per
treatment, while in Farm B, 8 sows per treatment.
The detailed description of the experimental design
is given on Table 1.
Animals and Feeding
In both farms sows were group housed during ges-
tation. Articial insemination was used and estrus
detection occurred with the presence of a teaser boar.
In Farm A, sows were transferred to the farrowing
Table 1. Number of sows allocated per treatment at the different stages of the experiment and nal number of sows that were included in the rst
and second reproductive cycle in both study farms
Parameter Farm A Farm B
Sows Capacity 550 220
Breed Topigs 40
Treatments CN1
AT2
AT+ 3
Initial Allocation of sows/ cycle 120 45
Sows by experimental criteria/ cycle 72 36
Sows per treatment/ cycle 24 12
Sows completed both cycles/ treatment 15 8
1 control group: standard gestation and lactation diet
2 attapulgite group: standard gestation and lactation diets were supplemented with 7 g/kg of feed of attapulgite
3 attapulgite+ group: standard gestation and lactation diets were supplemented with 8 g/kg of feed of an attapulgite blended product
196
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ascending scale until the 7th day of lactation after
which maximum allowance was reached. In Farm B,
during lactation sows were fed at a level of 2.5kg at
farrowing plus 400g/ piglet, divided over two meals
per day and the sows reached maximum feed allow-
ance till the 6th day of lactation. Main ingredients and
basic nutrient composition (calculated with EvaPig®
software) of the gestation and lactation diets is given
in Table 2. Water was available ad libitum. In both
farms, piglets were given free access to a commer-
cial creep feed from the 7th day after farrowing until
weaning.
Farm A
Gestation Diet Lactation Diet
Ingredients (kg/100kg of feed)
Maize 7.5 -
Wheat soft 40.0 46.0
Wheat bran 21.0 10.0
Barley 20.1 22.35
Soybean 44% CP 8.5 13.5
Soybean oil - 1.75
Fish meal 70% CP - 3.5
Calcium carbonate 1.65 1.5
L-Lysine HCl - 0.15
Mineral and vitamin premix 1.25 1.25
Nutrients
Crude Protein (%) 13.63 17.01
Crude Fat (%) 2.11 3.75
Crude Fibre (%) 4.41 3.78
Metabolizable Energy (MJ/kg) 12.27 13.08
Farm B
Gestation Diet Lactation Diet
Ingredients (kg/100kg of feed)
Maize 19.0 19.0
Wheat soft 17.4 20.5
Wheat bran 30.0 18.0
Barley 17.0 18.0
Soybean 44% CP 10.0 17.0
Soybean oil 1.5 2.0
Fish meal 70% CP 1.0 1.0
Yeast - 0.5
Mineral and vitamin premix 4.1 4.0
Nutrients
Crude Protein (%) 14.55 16.47
Crude Fat (%) 4.08 4.36
Crude Fibre (%) 4.93 4.38
Metabolizable Energy (MJ/kg) 12.18 12.78
Table 2. Main ingredients and nutrient composition of the gestation and lactation diet in Farm A and Farm B
ΚΑΝΟΎΛΑΣ Β., ΠΑΠΑΔΟΠΟΎΛΟΣ Γ.Α., ΑΡΣΕΝΟΣ Γ., ΤΖΗΚΑ Ε.Δ., ΦΟΡΤΟΜΑΡΗΣ Π.
197
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BW loss). In addition, the relative sow body weight
loss (%) during lactation was calculated by the
equation: SowBWloss%=[(SowBWf-SowBWw)/
SowBWf)*100]. Regarding piglet data, the litter size
24h postpartum (after cross-fostering) and at wean-
ing was measured in both farms. The number of still-
born piglets was also recorded. Piglets were weighed
Measured Parameters
In both farms sows’ body weight (Sow BW) was
measured at insemination (Sow BWi), at the transfer
to the farrowing room (Sow BWf), and at wean-
ing (Sow BWw). The body weight of the sows was
measured by a digital scale. Sow body weight loss
from late gestation to weaning was calculated (Sow
Parameters Treatment SEM P-value
CN
(n=24)
AT
(n=24)
AT+
(n=24)
Cycle 1
Parity 4.6 4.7 3.8 0.59 0.217
Sow BWi1, kg 217.9 224.0 222.0 10.50 0.716
Sow BWf1, kg 269.4 273.1 277.6 11.32 0.698
Sow BWw, kg 226.8 230.3 233.1 9.98 0.749
Sow BWloss, kg 42.7 43.1 44.2 4.34 0.942
Sow BWloss % 15.6 15.6 16.1 0.95 0.912
Litter size 24h postpartum110.7a12.5b12.1b0.50 0.001
Stillborn 1.2 0.9 1.2 0.39 0.655
Litter size weaning110.3a11.3b10.3a0.35 0.004
Piglet BWf, kg 1.6 1.5 1.6 0.06 0.124
Piglet BWw1, kg 6.5 6.6 6.6 0.24 0.846
ADG1, g/day 234.8 245.9 240.2 11.70 0.612
Cycle 2
Parity 5.1 4.8 4.0 0.58 0.121
Sow BWi1, kg 213.3 219.0 220.9 10.40 0.528
Sow BWf1, kg 275.1 275.9 272.0 8.13 0.883
Sow BWw1, kg 228.8 235.2 228.0 7.10 0.548
Sow BW loss, kg 46.3 40.8 43.8 4.75 0.501
Sow BWloss % 16.3 14.8 16.5 1.07 0.457
Litter size 24h postpartum112.1 12.6 12.1 0.59 0.565
Stillborn 0.9 0.8 0.8 0.24 0.862
Litter size weaning29.7a10.4b10.6b0.34 0.037
Piglet BWf, kg 1.6 1.6 1.5 0.07 0.630
Piglet BWw, kg 7.2 7.6 7.2 0.30 0.279
ADG, g/day 265.7 288.0 271.0 14.22 0.270
a,b Means with different superscripts within the same row differ signicantly between them (P<0.05)
1Parity was used as covariate, mean values within the same row represent adjusted means
2Litter size at 24h postpartum was used as covariate, mean values within the same row represent adjusted means
Sow BWi= sow body weight at insemination; Sow BWf=sow body weight at arrival at farrowing room; Sow BWw= sow body weight at wean-
ing; Sow BW loss= sow body weight loss from farrowing to weaning; Sow BWloss %= sow body weight loss from farrowing to weaning ex-
pressed in % related to sow body at farrowing; Piglet BWf= piglet body weight at 24h postpartum; Piglet BWw= piglet body weight at weaning;
ADG= average daily gain of piglets during lactation
Table 3. Sow and piglet performance in Farm A during cycles 1 and 2
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24h postpartum (Piglet BWf) and at weaning (Piglet
BWw). Average daily gain (ADG) was calculated
dividing the difference between Piglet BWw and
Piglet BWf by the number of lactation days for each
farm. Parity was also recorded.
Statistical Analysis
All statistical procedures were performed using SPSS
(SPSS 22.0 Version, Chicago, IL, USA). Statistical
significance was considered at P<0.05. Data were
analyzed with analysis of variance (ANOVA) of
GLM procedures. Data was checked for normality
of distribution with Kruskal-Wallis test and equal-
ity of differences with Levene’s test. Treatment was
included as xed factor.
At a first step, each cycle and for each farm was
Parameters Treatment SEM P-value
CN
(n=12)
AT
(n=12)
AT+
(n=12)
Cycle 1
Parity 4.2 4.5 4.9 0.64 0.761
Sow BWi1, kg 215.3x202.4y201.1y10.66 0.092
Sow BWf1, kg 259.5 257.9 262.7 6.35 0.747
Sow BWw1, kg 219.6 214.9 215.0 8.16 0.809
Sow BW loss, kg 31.4x45.3y53.7y8.02 0.063
SowBWloss% 15.4 16.6 18.0 1.84 0.611
Litter size 24h postpartum110.6 11.1 10.2 0.59 0.252
Stillborn 0.75 0.5 1.1 0.38 0.303
Litter size weaning 9.9ab 10.2a8.9b0.51 0.037
Piglet BWf, kg 1.4 1.5 1.6 0.09 0.412
Piglet BWw2, kg 8.6 9.1 8.2 0.58 0.174
ADG, g/day 214.7 245.5 221.2 14.89 0.109
Cycle 2
Parity 4.8 4.7 5.0 0.89 0.960
Sow BWi1, kg 220.5 209.5 216.3 8.07 0.362
Sow BWf, kg 262.3 250.8 259.9 7.31 0.276
Sow BWw1, kg 239.8x224.9y228.5xy 7.47 0.080
Sow BW loss, kg 22.5 26.7 29.2 4.63 0.277
SowBWloss% 8.6 10.6 11.8 1.22 0.192
Litter size 24h postpartum110.2 10.6 11.0 0.96 0.685
Stillborn 0.5 0.5 0.4 0.23 0.777
Litter size weaning 8.6 8.3 9.8 0.94 0.248
Piglet BWf, kg 1.5 1.4 1.5 0.09 0.250
Piglet BWw2, kg 8.3a8.5a9.8b0.33 <0.001
ADG, g/day 218.8 227.9 248.7 15.15 0.136
a,b Means with different superscripts within the same row differ signicantly between them (P<0.05)
x,y Means with different superscripts within the same row tend to differ signicantly between them (0.05<P<0.1)
1Parity was used as covariate, mean values within the same row represent adjusted means
2Litter size at 24h postpartum was used as covariate, mean values within the same row represent adjusted means
Sow BWi= sow body weight at insemination; Sow BWf=sow body weight at arrival at farrowing room; Sow BWw= sow body weight at weaning;
Sow BW loss= sow body weight loss from farrowing to weaning; Sow BWloss %= sow body weight loss from farrowing to weaning expressed
in % related to sow body at farrowing; Piglet BWf= piglet body weight at 24h postpartum; Piglet BWw= piglet body weight at weaning; ADG=
average daily gain of piglets during lactation
Table 4. Sow and piglet performance in Farm B during cycles 1 and 2
ΚΑΝΟΎΛΑΣ Β., ΠΑΠΑΔΟΠΟΎΛΟΣ Γ.Α., ΑΡΣΕΝΟΣ Γ., ΤΖΗΚΑ Ε.Δ., ΦΟΡΤΟΜΑΡΗΣ Π.
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analyzed separately. Parity, sow BWins were tested
as covariates for SowBWf. The SowBWf was used
as a covariate for SowBWw. Parity was tested as a
covariate for all the rest recorded parameters. Litter
size 24h postpartum was tested as a covariate for
piglet BWf, piglet BWw and ADG. At a second step,
in order to evaluate the treatment effects in sows that
completed both cycles in each farm separately, the
GLM repeated measures analysis was used. Treatment
was included as between subject factor, and cycle 1
and 2 were included as within subject factors. Results
were reported as least square means ± SEM. In case
of signicant relationship of a covariate, results were
reported as estimated marginal means.
RESULTS
Results from each farm and per cycle
The results of sow and piglet performance parameters
during both phases (cycles 1 and 2) from Farm A
are presented in Table 3. No signicant differences
were detected for sow related characteristics either
for cycle 1 or for cycle 2. Regarding piglet data,
during cycle 1 signicant differences between treat-
ments were noted for litter size 24h postpartum and
at weaning. Specically, litter size 24h postpartum
was greater for AT and AT+ groups compared to
CN (P=0.001). Moreover, litter size at weaning was
greater in AT than the other two groups (P=0.004).
During cycle 2, the only signicant effect was detect-
ed for litter size at weaning, which was in favour of
AT and AT+ compared to CN group (P=0.037). One
of the most important parameters to evaluate sow
and litter performance during the lactation period is
piglets’ growth. Although not statistically signicant,
numerical differences were recorded in the ADG
of piglets in favour of the attapulgite supplemented
groups.
The results of sow and piglet performance param-
eters during both phases (cycles 1 and 2) from Farm
B are presented in Table 4. During cycle 1, sow BW
at insemination tended to be higher in CN compared
to the other two groups (P=0.092). The sow BW loss
from late gestation to weaning, tended to be higher
in AT and AT+ than CN group (P=0.063). During
cycle 2, sow body weight at weaning tended to be
higher in the CN than AT sows (P=0.080). Regarding
Parameters Treatment SEM P-value
CN
(n=15)
AT
(n=15)
AT+
(n=15)
Sow BWi, kg 214.4 219.1 228.2 9.19 0.561
Sow BWf, kg 265.9 275.4 282.2 9.67 0.497
Sow BWw, kg 227.5 227.8 236.1 8.96 0.744
Sow BW loss, kg 38.4a47.5b46.0b2.40 0.023
Sow BW loss% 14.5x17.4y16.2y0.82 0.052
Litter size 24h postpartum 11.5a12.8b12.1ab 0.31 0.011
Stillborn 1.0 0.9 0.6 0.19 0.451
Litter size weaning 10.2a11.2b10.3a0.25 0.022
Piglet BWf, kg 1.6 1.6 1.6 0.04 0.662
Piglet BWw, kg 6.7a7.3b6.8a0.18 0.049
ADG, g/day 183.7a206.1b185.9a9.35 0.040
a,b Means with different superscripts within the same row differ signicantly between them (P<0.05)
x,y Means with different superscripts within the same row tend to differ signicantly between them (0.05<P<0.1)
Sow BWi= sow body weight at insemination; Sow BWf=sow body weight at arrival at farrowing room; Sow BWw= sow body weight at wean-
ing; Sow BW loss= sow body weight loss from farrowing to weaning; Sow BWloss %= sow body weight loss from farrowing to weaning ex-
pressed in % related to sow body at farrowing; Piglet BWf= piglet body weight at 24h postpartum; Piglet BWw= piglet body weight at weaning;
ADG= average daily gain of piglets during lactation
Table 5. Treatment effects in Farm A after repeated measured analysis in sows that completed both reproductive cycles
200
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In Farm B no signicant differences between treat-
ments were detected regarding sow and litter perfor-
mance parameters. However, a clear trend regarding
sow BW loss, sow BW loss (%) and ADG of pig-
lets was observed for the attapulgite supplemented
groups, where values were greater compared to con-
trol group. Furthermore, litter size 24h postpartum
and at weaning, was numerically higher in the atta-
pulgite supplemented groups compared to control
group.
DISCUSSION
The present study investigated the effects of dietary
attapulgite supplementation during gestation and
lactation on sows’ performance. The study protocol
implemented the follow up of two consecutive repro-
ductive phases (cycles) in two commercial farms.
Thus, it was possible to investigate the repetition of
treatment effects over a two cycle period. Moreover,
as both farms differed in terms of size (number of
sows), location and feeding practices the effects of
attapulgite supplementation under different husband-
ry conditions were also evaluated.
In the present study, litter size 24h postpartum was
piglet data, during cycle 1 litter size at weaning was
higher in group AT than AT+, with the CN group
being indifferent from the other 2 groups (P=0.037).
During cycle 2, piglet weight at weaning was higher
in AT+ than the other 2 groups (P<0.001). The ADG
of piglets in both cycles was again not statistically sig-
nicant, but also numerically greater in the attapulgite
supplemented groups compared to the control one.
Repeated Measures Analysis
The results of treatment effects after repeated meas-
ures analysis of data from sows that completed both
cycles from Farm A and Farm B are presented in
Tables 5 and 6, respectively.
In Farm A (Table 5), the calculated sow BW loss
was greater for AT and AT+ groups compared to CN
(P=0.023). Likewise, the % of sow BW loss dur-
ing lactation tended to be greater for AT and AT+
groups compared to CN (P=0.052). Litter size 24h
postpartum, litter size at weaning and piglet BW
at weaning were higher in AT than CN and AT+
groups (P=0.011, P=0.022 and P=0.049, respec-
tively). Finally, the ADG of piglets during lactation
was higher in AT compared to CN and AT+ groups
(P=0.040).
Parameters Treatment SEM P-value
CN
(n=8)
AT
(n=8)
AT+
(n=8)
Sow BWi, kg 210.3 200.5 204.5 6.82 0.603
Sow BWf, kg 254.5 250.4 260.4 6.14 0.522
Sow BWw, kg 224.4 213.7 221.0 6.35 0.489
Sow BW loss, kg 30.1 37.3 39.4 3.28 0.133
SowBWloss% 11.8 14.6 15.2 1.32 0.176
Litter size 24h postpartum 10.4 11.4 11.0 0.51 0.352
Stillborn 0.6 0.6 0.8 0.19 0.860
Litter size weaning 9.1 9.4 9.6 0.50 0.768
Piglet BWf, kg 1.4 1.4 1.5 0.05 0.154
Piglet BWw, kg 8.7 8.8 8.8 0.25 0.958
ADG, g/day 216.9 240.8 234.4 8.26 0.132
Sow BWi= sow body weight at insemination; Sow BWf=sow body weight at arrival at farrowing room; Sow BWw= sow body weight at wean-
ing; Sow BW loss= sow body weight loss from farrowing to weaning; Sow BWloss %= sow body weight loss from farrowing to weaning ex-
pressed in % related to sow body at farrowing; Piglet BWf= piglet body weight at 24h postpartum; Piglet BWw= piglet body weight at weaning;
ADG= average daily gain of piglets during lactation
Table 6. Treatment effects in Farm B after repeated measured analysis in sows that completed both reproductive cycles
ΚΑΝΟΎΛΑΣ Β., ΠΑΠΑΔΟΠΟΎΛΟΣ Γ.Α., ΑΡΣΕΝΟΣ Γ., ΤΖΗΚΑ Ε.Δ., ΦΟΡΤΟΜΑΡΗΣ Π.
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J HELLENIC VET MED SOC 2017, 68(2)
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in improved litter size and piglet weight at farrowing
(Kyriakis et al., 2002).
The nding of an increased sow BW loss in groups
supplemented with attapulgite, supports the nding
of the improved piglet performance in the specic
groups. The consistency of this nding was further
validated by repeated measures analysis of sows that
participated in both phases. Specically, the repeated
measures analysis of sow BW loss % in both farms,
revealed that attapulgite supplemented sows mobi-
lized proportionally more body weight during lacta-
tion than the control ones. Litter size is the driving
force of milk production in the sow and a higher
litter size induces higher milk production (Auldist
et al., 1998). The sow during lactation mobilizes
body reserves in order to support the growth of the
nursing piglets, as feed intake is suboptimal (Eissen
et al., 2003). The underlying mechanism under this
metabolic effect of attapulgite on increased sow
body weight mobilization during lactation remains
to be investigated. Attapulgite, due to its high water
binding capacity, has been used in human medi-
cine as a product to reduce diarrhea (Carretero and
Pozo, 2010). It could be hypothesized that in sows
attapulgite caused a decreased gut transition rate.
This may have resulted in a gradual release of nutri-
ents, inducing in this way a greater mobilization of
body reserves to cover the needs for piglet growth.
Consequently, the mobilization of body reserves
by the attapulgite supplemented sows reflected in
improved weight gain of piglets during lactation.
Such information on body weight changes of sows
during lactation after clay supplementation is absent
in previous studies that demonstrated improved pig-
let weight gain (Kyriakis et al., 2002; Papaioannou et
al., 2002). These effects became signicant in Farm
A, whereas in Farm B numerical differences were
detected in favour of attapulgite groups; this should
be attributed to the number of replicates, either in
the single phases (cycle) or in the repeated measure-
ments analysis of data in Farm B.
Despite the fact that the compound form (AT+) con-
tained the same amount of attapulgite as of the pure
product (AT), the obtained results were different
between farms. The latter could be attributed to the
feeding regime in the two farms. As the total cere-
al amount containing Non-Starch Polysaccharides
affected by attapulgite supplementation in sows.
This effect was more consistent in Farm A sows, and
especially in those that completed both cycles. The
same effect was also evident at litter size at weaning.
Although litter size as a single factor for the evalua-
tion of the reproductive performance of sows alone
has a limited value, as it can be largely affected by
numerous factors, the persistency of this effect in
sows that completed both cycles, suggests that atta-
pulgite requires continuous supplementation in sow
feeding in order to affect litter size parameters. The
output of a pig farm is estimated upon the number of
piglets weaned per sow per cycle or per year basis,
and therefore influencing positively litter size at
weaning is a demand in the eld. Successful breed-
ing programs have resulted in a signicant increase
in litter size in the modern hyper-prolic sow (Kemp
and Soede, 2012). Litter size at farrowing can be
inuenced mainly during the early stages of gestation
in sows. An increased feeding level during the rst 4
weeks of gestation improved embryonic and placen-
tal development through an increased availability of
specic micronutrients, such as folic acid and argi-
nine (Matte et al., 1996). Thus, an increased feeding
level might stimulate embryonic and placental devel-
opment, and thereby embryo survival, by its inu-
ence on IGF-1 (Hoving et al., 2011). Similar results
were previously reported after dietary inclusion of
another clay (clinoptilolite) in sow diets, where an
increased litter size both at birth and at weaning
accompanied by increased piglet body weight at birth
and at weaning (Papaioannou et al., 2002). The latter
study attributed the improvements of piglet charac-
teristics to an improvement in nutritional efciency
of the sow during late gestation and also to a spar-
ing effect of nutrients and energy for a better lacta-
tion performance. In the present study sows from
both farms were fed restrictively during gestation.
Therefore, possible differences in litter size at far-
rowing could not be attributed to an increased feed-
ing allowance during the rst stages of gestation but
to the effect of attapulgite. The fact that attapulgite
supplementation in sows did not cause differences
on piglet weight 24h postpartum, suggests that sup-
ply of nutrients in utero did not affect fetus growth
and weight. Elsewhere, dietary supplementation of
sows with clinoptilolite-rich tuff clay, resulted both
202
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J HELLENIC VET MED SOC 2017, 68(2)
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date the underlying mechanisms involved, especially
regarding to sow metabolism.
CONFLICT OF INTEREST STATEMENT
The authors declare no conict of interest.
ACKNOWELDEMENTS
The present research project was funded by
Geohellas S.A. (Decision 67555, Code 85152,
Research Committee of Aristotle University of
Thessaloniki). The authors wish to acknowledge Dr
N. Theophilou (Geohellas S.A.), A. Manouras and Dr
I. Skoufos for their technical and scientic support.
Also V. Giannakis, E. Tsapouri and G. Bramis for
their assistance in the experimental phase of this
work.
(NSPs, e.g. barley and wheat) added was higher
in Farm A, it is plausible that the additives such as
yeasts or enzymes may not act synergistically with
attapulgite. Is known that NSP enzymes reduce diges-
ta viscosity and thus promote intestinal transit time
(Diebold et al., 2004). In the contrary, a clear effect
was evident in Farm B, where the total NSP cereals
were lower (38.5% vs 68.4% for the lactation diets).
CONCLUSIONS
Supplementation of attapulgite in sow diets during
gestation and lactation in two commercial farms in
Greece resulted in the improvement of performance
indexes such as sow body reserves mobilization, lit-
ter size characteristics and piglet growth. However,
results should be cautiously extrapolated to farms
differing in the feeding regime, in their size and in
their productivity. Further research is needed to eluci-
ΚΑΝΟΎΛΑΣ Β., ΠΑΠΑΔΟΠΟΎΛΟΣ Γ.Α., ΑΡΣΕΝΟΣ Γ., ΤΖΗΚΑ Ε.Δ., ΦΟΡΤΟΜΑΡΗΣ Π.
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