Morphological studies on rumen development in West African Dwarf goats (Capra hircus)

We studied the gross and light microscopic structures of rumen in fetal, neonatal and adult West African Dwarf (WAD) goats obtained from Nsukka and Igboeze South Local Government Areas (L.G.A) of Enugu State. After euthanasia the rumen was ligated, dissected out and the volume determined by flotation and displacement method. For histological studies pieces of rumen were fixed in Bouin`s fluid for 24hrs, processed and routinely stained with H & E. The volume of rumen was 7.25 ± 1.62, 14.3 ± 2.1, 211.6 ± 36.0 and 1620.3 ± 46.5 ml for gestation day 87, full term fetuses, neonates and adult goats respectively. The rumen volume body mass indices were 18.03 ± 3.45, 10.75 ± 4.29, 87.08 ± 6.50 and 108.02 ± 10.65 for gestation day 87, full term fetuses, neonates and adults respectively. Grossly, the mucosal surface was smooth and beige in fetuses, velvety and greenish brown in neonates and adults. Microscopically, the mucosa was lined by stratified squamous epithelium which was divided into larger lighter luminal and darker basal zones in fetuses and early neonates. The dark basal zone had finger-like projections into the lighter zone- proprial papillae. The papillae were tiny and covered by thin keratin layer in 4- week-old neonates. They were very tall especially in the ventral ruminal sac and the epithelium covered by thick keratin in adult goats. These results provide baseline data on rumen development in WAD goats

Effect of Maternal Alcohol Consumption on Epididymal Growth in Neonatal Mice

A study was conducted to determine the effect of maternal alcohol consumption on the growth of epididymis in neonatal mice. Three groups of adult female mice were used. The pups of group 1 served as control while the pups of groups 2 and 3 were given 30% ethanol (v/v) during pregnancy and during pregnancy and lactation respectively. At 3, 4, 5 and 6 weeks of age, 10 male pups were randomly selected from each of the three groups and sacrificed. After sacrifice, the epididymis were dissected out and theirweights determined. The results of the study showed significant decrease in the weights and growth rates of the epididymis of the pups exposed to alcohol when compared with the controls. The study has therefore  demonstrated that maternal alcohol intake during pregnancy and duringpregnancy and lactation affects the growth of epididymis of the neonates and that the epididymis of the neonates exposed to alcohol attempted catch-up growth with the control

Incidence and pathogenicity profile of Listeria sp. isolated from food and environmental samples in Nsukka, Nigeria

Samples of beef, pork, goat meat, poultry, fish and vegetables purchased from a local market located in Nsukka, Enugu State, Nigeria were examined for the presence of Listeria species. Surface swab samples taken from butchers’ tables as well as soil samples from the field where cows and pigs were kept before slaughter were examined. Listeria species were isolated from all samples except the pork and goat meat samples. The highest incidence (100%) was observed in the soil and surface swabsamples, respectively, followed by the vegetable samples (85%) and the beef samples (80%). Only Listeria monocytogenes and Listeria ivanovii were pathogenic to test animals causing death within five days. L. monocytogenes induced pathological changes characterized by abscesses in the liver, pericarditis and frank haemorrhage in the kidneys. The most notable change was the accumulation of mononuclear cells in the loose connective tissue surrounding the bile ducts. This study shows thatthere is a high incidence of listerial organisms in various key elements of the Nigerian environment, including soil and foods of both animal and plant origin, which may pose a health risk for high-risk individuals. The study goes further to establish the major target organs of attack of the pathogenic Listeria species

Morphology of the oropharyngeak cavity and oesophagus of the farmed adult African catfish (Clarias gariepinus Burchell, 1822)

The morphology of the adult farmed African catfish -Clarias gariepinus a prominent omnivorous cultivable species in Nigeria was investigated. It revealed cornified horny plates lining the buccal surfaces of the lips. The tongue was not free moving, and the oesophagus was a narrow tube connecting the oropharyngeal cavity to the stomach with no valve or constriction separating it from the later. Histologically, the cavity wall was lined by stratified squamous epithelium containing eosinophilic club cells, mucous cells and taste buds. The laminar propria contained dense collagen fibres. No taste bud was seen on the tongue suggesting it non involvement in food selection through gustation unlike the cavity wall which contained taste buds. The oesophagus was lined by stratified mucous epithelium containing club cells. Histochemistry revealed the presence of neutral, acid and combination of the two. The large extent of oesophageal mucification indicates need for mucin lubrication of food since teleost is known to lack salivary glands and also an adaptation to ingestion of varied feed.La morfología bagre africano del adulto cultivado -Clarias gariepinus- una especie omnívoras cultivables prominente en Nigeria fue investigada. Reveló placas córneas que cubren las superficies vestibulares de los labios. La lengua no tiene movimiento libre y el esófago es un tubo estrecho que conecta la cavidad orofaríngea al estómago sin válvula o constricción que lo separe. Histológicamente, la pared de la cavidad estaba revestida por epitelio escamoso estratificado que contiene células eosinófilas, células mucosas y papilas gustativas. La laminar propia contenía fibras de colágeno denso. No fie vista ninguna papila gustativa en la lengua lo que sugiere la no participación la selección de los alimentos a través gustación a diferencia de la pared de la cavidad que contiene papilas gustativas. El esófago estaba revestido por epitelio estratificado que contiene células mucosas. La histoquímica reveló la presencia de ácido a neutro, y la combinación de los dos. La gran extensión de mucificación esofágica indica la necesidad de lubricación de mucina de los alimentos se sabe que los teleósteos carecen de glándulas salivales y también una adaptación a la ingestión de alimentos variados

Histologic and ultrastructural observations on the thyroid gland of the White Fulani (Zebu) cattle in Northern Nigeria

The histology and ultrastructure of thyroid gland of White Fulani (Zebu) cattle were examined during the postnatal developmental period to show if variations in morphology exist with age and in relation to tropical climate. Eight prepubertal and ten pubertal cattle of abattoir origin were used to carry out this study. Histologically, the thyroid consisted of well-developed capsule, interlobular connective tissue, follicular and parafollicular cells from prepubertal to pubertal age of 5 to 7 years. The follicular cells were cuboidal in prepubertal period with some variations, became predominantly columnar in pubertal age of 2 to 4 years and highly flattened cells were common in the older pubertal animals of  5 to 7 years. The colloid was observed in the lumen at all age and was PAS-positive with abundant peripheral vacuoles in the pubertal age of 2 to 4 years. Significant variations (p˂0.05) in structure of the thyroids were observed at all age and the follicular size and number of follicles increased as the cattle matured. Follicular height was reduced significantly in the older pubertal cattle of 5 to 7 years. Ultrastructurally, the follicular cells showed highly dilated cisternae of rough endoplasmic reticulum which decreased with age. Flattened follicular cells seen in the older pubertal cattle contained few cytoplasmic organelles and microvilli. Apically placed pseudopods and blebs were commonly observed in the pubertal age of 2 to 4 years. Lysosomal bodies increased with age of development. The parafollicular cells were encountered frequently in the prepubertal age than in the older cattle. They consisted of numerous dense secretory granules which increased in number with age. The present results suggest an optimum thyroid function during the pubertal. Our findings would be useful in interpreting changes in thyroid morphology during experimental and pathological conditions. Key words:  Cattle, postnatal thyroid, histology, ultrastructure

Histological study of the pharyngeal pad of the african catfish (Clarias gariepinus Burchell 1822)

The pharyngeal pad located dorsally on the oro-pharynx was processed for light microscopy. The epithelium was of stratified mucous type containing taste buds, club cells and teeth. The micromorphology revealed the co-localization of teeth and taste bud. Developing, erupting and erupted teeth were also seen. The thin bone of cancellous type with a marrow seen provided point of origin and insertion for the skeletal muscle present. Osteoblasts were seen on the surface of the cancellous bone probably depositing bone matrix. The pad had a base of hyaline cartilage. Stratum adiposum was observed and may be site for nutrient storage and also function in reducing friction between sliding muscle fibres since it was sandwiched between muscle fibres. The micromorphology suggest an organ used in trituration and selection of food by gustation. The blood vessels in the bone marrow suggest haematopoietic function. The bone and cartilage present is for support.Keywords: Pharyngeal pad, Histology, Food selection, Taste bud, African catfishAnimal Research International (2012) 9(3): 1613 – 161