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Peculiarities of the Camel and Sheep Narial Musculature in Relation to the Clinical Value and the Mechanism of Narial Closure

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Abstract

The camel closes its nostril during adverse climatic condition, that may be indicative for unusual muscular anatomy. The camel seems to have a group of muscles similar to that of the proboscis-bearing animals. The proboscis is a muscular nose able to close by the aid of the maxillolabial group of muscles and the lateralis nasi, coupled with evacuation of air through certain vestibular recesses. This article, suggested similar mechanism in camel, as the structure and attachments of narial muscles were close to that found in the proboscideal nose. Clinical value was stepping on determination of the site for definite surgical interference.
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A little is known about the anatomy of the camel
narial musculature (Ali et al., 1979; Smuts and
Bezuidenhaut, 1987). The nasal region has a special
importance in racing camel, as they sometimes need a
surgical operation for widening their nasal opening. So the
anatomy of this region should be studied in details to avoid
the destruction of nasal cartilages or the other related
structures during such operations. Camel is the only
domesticated animal known for its ability to close the
nostrils. The nose of camel (Camelus dromedarius) and
sheep (Ovis aries) are similar in terms of external shape,
but camel nose closes during sand storms while sheep nose
remains open. So, the paper compared the narial
musculature of camel and sheep and discussed the
mechanism of narial closure.
MATERIALS AND METHODS
This study was carried out on 20 heads of apparently
healthy adult animals, 10 camels and 10 sheep. Camels
and sheep heads were obtained immediately after slaughter
from Toukh abattoir in Qaloibia. The heads were examined
before and after slaughtering to record the narial shape
and flexibility. The bled heads were injected through the
common carotid artery with 10% formalin solution and kept
in 10% formalin, 4% phenol and 1% glycerin solution for
preservation.
RESULTS AND DISCUSSION
In the camel, the rostral part of the nasal septum
was muscular and extended along the nasal vestibule
(Fig. 1) as reported earlier (Badawi and Fateh-El-Bab,
1974). The Nasal septum in proboscis-bearing animals ex.
Saiga antelope has a large membranous anterior portion as
recorded by Frey and Hofmann (1997). Narial muscles in
camel and sheep were m. levator nasolabialis; m. levator
labii maxillaris; m. caninus; m. depressor labii maxillaris;
m. lateralis nasi and m. transversus nasi. These muscles
arranged in four layers were the maxillolabial group of
muscles (m. levator labii maxillaris; m. caninus; m.
depressor labii maxillaris) (Figs. 2, 3). The deep part of the
levator nasolabialis which formed the third layer in the
camel was absent in sheep. The fourth layer was the most
medial one and formed by the strong lateral nasal muscle.
M. levator nasolabialis was a flat rectangular muscle,
intimately adherent to the skin and was divided into
superficial and deep layers in camel. The maxillolabial group
of muscles passed between these two layers as reported
by Nickel et al. (1979) in ox, and differ from that found in
sheep as this muscle was a single thin layer. The levator
nasolabialis arose from the frontal and nasal fascia. It
inserted in the lateral nasal angle and the adjacent parts of
the upper lip in sheep. While, in the camel, the superficial
layer of this muscle inserted along the lateral wing of the
nostril and the upper lip (Fig. 4). In both animals, the muscle
fibres attached to the skin at the insertion site and
Indian Journal of Veterinary Anatomy 26 (1): 10-13, June 2014
Peculiarities of the Camel and Sheep Narial Musculature in Relation to the Clinical
Value and the Mechanism of Narial Closure
Eman A. Eshra1* and Adel M. Badawy2
Department of Anatomy and Embryology1, Department of Surgery and Radiology2
Faculty of Veterinary Medicine, Benha University, Egypt-13736
Received: 14 December 2013; Accepted: 19 February 2014
ABSTRACT
The camel closes its nostril during adverse climatic condition, that may be indicative for unusual muscular
anatomy. The camel seems to have a group of muscles similar to that of the proboscis-bearing animals. The
proboscis is a muscular nose able to close by the aid of the maxillolabial group of muscles and the lateralis nasi,
coupled with evacuation of air through certain vestibular recesses. This article, suggested similar mechanism in
camel, as the structure and attachments of narial muscles were close to that found in the proboscideal nose.
Clinical value was stepping on determination of the site for definite surgical interference.
Key words: Lateralis nasi, Levator labii maxillaries, Narial muscles, Nasolabialis
1 Lecturer; 2 Asstt. Prof., Surgery & Radiology
*Corresponding author: eman.eshrah01@fvtm.bu.edu.eg
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(2003) in saiga and moose. While in camel, the muscle
fibres blended with that of the levator nasolabialis and
orbicularis oris muscles. Thus, the insertion site at the upper
lip formed a network of muscle fibres shared by the other
maxillolabial muscles.
M. caninus (dilator naris lateralis) was the middle
muscle of the maxillolabial group. It was the tiniest member
of this group of sheep (Fig. 2) similar to that observed by
Saber (1987) in goat. Moreover, this muscle sending out
thin single tendon for insertion on the lateral accessory
nasal cartilage, while it ended abruptly on this cartilage in
camel. M. depressor labii maxillaris was the ventral-most
muscle of the group. In its middle it was divided into dorsal
and ventral branches in sheep (Fig. 2), as it was in ruminants
(Nickel et al., 1979), while it was not divided in camel.
The muscle ended on the upper lip and the ventral portion
of the nostril in both animals.
M. lateralis nasi was not present in sheep to the
extent that it was in camel. It arose from the dorsal lateral
nasal cartilage in camel, while it arose from the nasal bone,
the dorsal and ventral lateral nasal cartilages in sheep. In
both animals, the muscle terminated in the lateral wing of
the nostrils in common with muscle fibres of the deep layer
of the levator nasolabialis and the maxillolabial group, similar
to that found in ruminants (Nickel et al., 1979). The lateral
nasal diverticulum was a small vestibular outpouching located
between the maxillolabial group laterally and the lateralis
nasi medially. The lateral nasal diverticulum present in camel
was somewhat similar to the lateral nasal sac of saiga
antelope (Clifford, 2003; Clifford and Witmer, 2004). M.
transversus nasi was an unpaired, small quadrilateral muscle,
which was located between the medial wings of the nostrils
as reported in domestic animals (Nickel et al., 1979).
The nostrils in the camel and sheep were slit like
with rostro-medially directed longitudinal axis (Figs. 1, 2)
that also observed by Badawi and Fathel-bab (1974). At
first glance, it may seem that the nose of camel and sheep
are similar, but after apparently examined before and after
slaughter, it turns out they're totally different. The
examination showed that the camel nose was relaxed and
sagged over the upper lip (Fig. 1), while the sheep nose
remained tight and the shape of the nostrils was not changed.
The sag nose of camel revealed the internal structure that
allowed this to happen. The lateral wall of the camel nose
and the rostral portion of the nasal septum were composed
entirely of muscles. These muscles were more extensive
than in sheep and the attachment and relations were
different. Muscles in camel were mostly related and
attached to deficient and liable osseo-cartilagenous
skeleton. In camel the bones surrounding the nasal opening
were reduced and very short, especially when compared
to that of the rest of ruminants (Smuts and Bezuidenhout,
1987). The shortness of nasal bone in camel gave the
opportunity to extend the dorsal nasal cartilage for a distance
of up to two-thirds the length of the nasal cavity, the medial
and the lateral accessory nasal cartilages were very small
and the ventral nasal cartilage was absent, therefore the
lateral wall of the nose is devoid of cartilage.
When combining the above-mentioned facts together,
it is clear that the camel nose anatomy is unique among the
domesticated animals. In ruminants, equines and carnivores
the bones formed the caudal two-thirds of the nose, leaving
the anterior-third for the cartilages and muscles, i.e the
skeleton of the nose is mostly osseo-cartilagenous (Nickel
et al., 1979 in domestic animals. The reduction in the bones
and cartilages of the camel nose and the remarkable
expansion of narial muscles has resulted in an organ that is
might be interpreted as a proboscis.
Proboscis can be defined generally as flexible snout,
has the ability to closure by the aid of the maxillolabial
muscles. There are two types of proboscis, the first type,
known as the maxillolabial proboscis characterized by the
presence of mobile elongation of the rostral end of the
nose. This type was present in pigs Suidae, peccaries
Tayassuidae, Coatis procyonidae and the elephant shrews
Macroscelidia. The second type was known as the
vestibular proboscis and can be defined as a nose has fleshy
end and sags over the upper and lower lips when relaxed.
The vestibular proboscis was present in moose (Alces
alces), Saiga antelope (Saiga tatarica) and dik-dik
(Madqua guntheri smithi) (Clifford, 2003). There are
many matches between the anatomy of the camel nose
and the vestibular proboscis, both of them have nasal bones
retracted or reduced, and the maxilla usually formed a large
portion of the margin of bony naris as observed by Clifford
(2003) in moose and Saiga antelope. The presence of well
developed three maxillolabial muscles in the camel, rostral
muscular part of the nasal septum and the lateral nasal
diverticulum. In addition to the previously mentioned
matches, the presence of a proboscis also has resulted in a
major transformation of the internal anatomy of nasal cavity
as an expansion of the nasal vestibule, change in the position
of the opening of nasolacrimal duct and retraction and
Nasal Musculature Camel Sheep
13
modification of the bony turbinates (Witmer et al., 1999;
Clifford and Witmer, 2004). The first difference appeared
when compared the size of the camel nose to the usual size
of the proboscis, as the apex of the camel nose and the
nasal vestibule was relatively small. The second difference
was in the appearance of the nose in the living animal, the
nose of the living camel appeared somewhat rigid and fixed,
while it relaxed and sages over the upper lip only after the
slaughtering and before rigor mortis.
Closuring natural orifices usually associated with the
presence of sphincter muscles. In the camel, Smuts and
Bezuidenhout (1987) stated that, the muscles of the nostrils
are arranged in such a way that sphincter formed enables
the nostrils to close. The aforementioned statement does
not provide a full explanation for the closure
mechanism as the narial closure not depends only on the
action of muscles, but also might be attributed to the
deficient osseocartrilaginous skeleton, musculo-membranous
septum and retracted turbinates which arranged in such away
enables the muscles to close the nostril.
Comparison between the camel and the proboscis-
bearing mammals facilitates understanding of the closure
mechanism of the nostrils. Camel and Siaga antelope forced
to close their nostrils during sand storms. Moose tightly
closes the nostrils when diving in cold water to feed on the
underwater plants. The closure mechanism of the
proboscideal nose depends on the apposition of the dorsal
and ventral wings of the nostrils coupled with evacuation
of air from the vestibular recesses as suggested by Clifford
(2003) in Saiga and moose and Witmer et al. (1999) in
tapirs. In the camel, the lateral nasal diverticulum was a
cylindrical shaped pouch, pierces the lateral wall of the
nasal vestibule and opened at the level of limen nasi
(Arnautovic and Abdalla, 1969). This diverticulum located
between the maxillolabial muscles laterally and the lateralis
nasi medially, so it compressed during these muscles work
to appose the wings of the nostrils. Results showed that
the M. levator labii maxillaris, M. levator labii mandibularis
and the labial part of M. levator nasolabialis of camel were
all directly connected to the orbicularis oris muscle without
forming tendons for insertion as occurred in other ruminants
(Nickel et al., 1979) and the proboscis-bearing animals Saber
(1987) in dik-dik and Clifford (2003) in Saiga and moose. So
the orbicularis oris muscle and the levator nasolabialis may
have a role in the closure of the camel nostrils.
In the camel, the muscles of the nostrils arranged in
such a way similar to that of the proboscideal nose. In
addition, all the narial muscles are united at their insertions,
this may enable them to act as one unit closing the
nostrils. This action coupled with evacuation of air through
the lateral nasal diverticulum may provide an explanation
of the narial closure mechanism in camel. Although
validation of this mechanism has not been tested
experimentally, the narial anatomy would suggest that this
hypothesis is feasible.
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Nickel, R., Shummer A. and Seiferle, E. 1979. The Locomotor
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... Camel nose like any other proboscideal organs can work as a muscular hydrostat, which formed as a result of the reduction of bony and cartilaginous skeleton, coupled with the enlarged musculature and the nasolabial fusion. Such muscular hydrostat can dynamically regulate the nasal air flow, allowing for collection of the inspired particulate and thus cleansing of the inspired air, which is a coordinated adaptation to the dusty environment (Clifford and Witmer, 2004;Eshra and Badawy, 2014). In adverse climatic condition, such as sandstorm, it can allow for complete closure of the nostrils (Eshra and Badawy, 2014). ...
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... Camel nose like any other proboscideal organs can work as a muscular hydrostat, which formed as a result of the reduction of bony and cartilaginous skeleton, coupled with the enlarged musculature and the nasolabial fusion. Such muscular hydrostat can dynamically regulate the nasal air flow, allowing for collection of the inspired particulate and thus cleansing of the inspired air, which is a coordinated adaptation to the dusty environment (Clifford and Witmer, 2004;Eshra and Badawy, 2014). In adverse climatic condition, such as sandstorm, it can allow for complete closure of the nostrils (Eshra and Badawy, 2014). ...
... Such muscular hydrostat can dynamically regulate the nasal air flow, allowing for collection of the inspired particulate and thus cleansing of the inspired air, which is a coordinated adaptation to the dusty environment (Clifford and Witmer, 2004;Eshra and Badawy, 2014). In adverse climatic condition, such as sandstorm, it can allow for complete closure of the nostrils (Eshra and Badawy, 2014). ...
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Myology of the face region of the one-humped camel (Camelus dromedarius)
  • M A Ali
  • I M S Khidr
  • M A A El-Hagri
Ali, M.A., Khidr, I.M.S. and El-Hagri, M.A.A. 1979. Myology of the face region of the one-humped camel (Camelus dromedarius). Zagazig Veterinary Journal II: 151-160.
The Locomotor System of the Domestic Animals. 2 nd revised edn
  • R Nickel
  • A Shummer
  • E Seiferle
Nickel, R., Shummer A. and Seiferle, E. 1979. The Locomotor System of the Domestic Animals. 2 nd revised edn., Verlag Paul Parey, Berlin, Hamburg.
The musculature of the head of dik-dik (Madqua guntheri smithi) and goat (Capra hircus)
  • A S Saber
Saber, A.S., 1987. The musculature of the head of dik-dik (Madqua guntheri smithi) and goat (Capra hircus). Assuit Veterinary Medical Journal 19: 3-7.