J. Devi

Changes in the Seminiferous Epithelium of the Testes during Postnatal Development in Assam Goat

The present work is conducted to elucidate the postnatal development of the seminiferous epithelium of the testes of the Assam goats from 0 day to 10 months of age. A total of eighteen Assam goats divided into six age groups, namely, group-I (0-day), group-II (2 months), group-III (4 months), group-IV (6 months), group-V (8 months), and group-VI (10 months), consisting of 3 animals in each group were used in this study. The seminiferous tubules did not have lumina up to the age of 2 months, hence called the sex cords, and these contained centrally placed gonocytes and peripherally located sustentacular cells. Initiation of spermatogenesis started in 4-month old kids. Luminization process was completed by 6 months of age with all the seminiferous tubuyes having well-developed lumina at this age. These seminiferous tubules contained all the spermatogenic cells of the adult testis. Onset of puberty was observed to be established at 6 months of age in the Assam goats as evidenced by presence of spermatozoa adhering to the adluminal border of the Sertoli cells as well as in the tubular lumen. The histomorphology of various cells of the seminiferous epithelium has been described.

Postnatal Gross Morphological and Histoenzymic Studies on the Thyroid Gland of Assam Goat

The thyroid gland was composed of right and left lateral lobes connected by a narrow isthmus. The location of the isthmus over the trachea varied in male goats which ranged from 4th to 9th tracheal rings. Various biometrical parameters viz. length, width, thickness and weight of the thyroid gland showed a highly significant (P<0.01) increase between various age groups as well as between the thyroids of right and left sides of the body in Assam goats. Accessory thyroid tissue was not observed in any of the male goats. Different biometrical parameters of the isthmus showed an increasing trend with the advancement of age and the variations were found to be highly significant (P<0.01) between various age groups, except in respect of their weight. The activity of LDH in the follicular epithelium of the thyroid gland varied from weak to intense from 4 to 10 months of age (groupsIII to VI). However, MDH showed a strong activity in these cells at birth (group-I), which was reduced to moderate in 4 month old kids (group-III) and again elevated in older goats. The enzymic activity of G-6-PDH was variable from mild to moderate in the male goats. The intertubular stroma of the thyroid gland showed no activity for MDH and G-6-PDH in all the age groups. But a mild activity of LDH enzyme was seen in goats from 6 month of age (group-IV) onwards.

Post Natal Changes in the Concentration of certain Serum Biochemicals, Metabolic and Steroid Hormones in Male Assam Goats (Capra hircus) from Birth to Ten Months of Age

The mean concentration of blood glucose showed an increasing pattern with advancing age in the male Assam goats ranging from 39.32 ± 0.12 mg percent at birth to 51.92 ± 0.05 mg percent in 10 months old bucks. Serum cholesterol concentration showed a declining trend that varied from 108.93 ± 1.35 mg percent at birth to 62.23 ± 0.66 mg percent in 10 months old goats. Similarly, the levels of serum total protein increased from 3.96 ± 1.35 to 8.16 ± 0.02 g percent at birth and at 10 month of age, respectively. The serum thyroid hormones showed a declining trend in the male Assam goats with increasing age. The mean concentrations of Triiodothyronine (T3) and Thyroxine (T4) were recorded as 1.65 ± 0.03 and 114.38 ± 0.62 ng/ml at birth and 0.81 ± 0.01 and 24.47 ± 0.31 ng/ml at 10 months of age respectively. On the other hand, serum concentrations of testosterone hormone raised from 0.11 ± 0.01 ng/ml in 2 months old kids to 1.13 ± 0.01 ng/ml in the goats at 10 month of age. Testosterone could not be estimated in the serum of day-old kids because the level was too low to measure. Serum concentrations of all the hormones showed a highly significant (P<0.01) variation between different age groups under study.

Effect of Extreme Seasons on Some Blood Biochemical Parameters in Beetal and Toggenberg Goats of Jammu Region

The influence of extreme environmental conditions on biochemical parameters were studied in 36 healthy adult female (2-4 years of age) Beetal (n=18) and Toggenberg (n=18) goats in Jammu (J&K, India). Blood glucose, total cholesterol, total protein, albumin and blood urea nitrogen (BUN) levels were studied during moderate (autumn), extreme hot (summer) and extreme cold (winter) ambiences. Ambient temperature (0C) and relative humidity (%) were recorded and temperature-humidity index (THI) was calculated. For the season and breed interaction, significantly higher (P<0.01) total protein and cholesterol levels were found in Toggenberg goats in all the seasons. Significantly higher (P<0.01) levels of total protein, albumin and BUN levels were found during summer as compared to autumn and winter seasons. The concentrations of glucose and cholesterol were significantly higher (P<0.01) in winter season. Among the two breeds, all the values were significantly higher (P<0.01) in Toggenberg. Biochemical parameters change in different seasons and THI values were found higher during summer season and is considered as danger status.

Histomorphological Development of Lingual Taste Buds in Goat (Capra hircus)

The present study was conducted on the tongue of 18 goat foeti, divided into 3 prenatal age groups viz., group 1 ( 100 days of gestation) containing 6 foeti in each group, to assess sequential events in the development of taste buds. The first appearance of primitive taste buds was observed on the apical surface of circumvallate and fungiform papillae in 93 days old goat foetus (CRL = 20.6 cm). The fungiform papillae located on the apex and body region of tongue were devoid of any taste buds. At 120 days of gestation (CRL = 31.1 cm), the taste buds were ovoid in shape and contained elongated or spindle shaped cells. The taste pores were apparent in taste buds at 146 days of gestation (CRL= 35.5 cm). Themeannumberoftaste buds in circumvallate papillae in this group was 2.0±0.36. The mean number of taste buds in fungiform and circumvallate papillae in tongue of goat foeti in group III was 1.83±0.3 and 5.5±1.08, respectively. A significant increase in the number of taste buds was observed in circumvallate papillae between group II and III.