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Aim:The present investigation was undertaken to study the reproduction performance and effect of non-genetic factors on reproduction performance of Jersey crossbred cows.Materials and Methods:Data on 355 Jersey crossbred cattle maintained at the Post-graduate Research Institute in Animal Sciences, Kattupakkam, Tamil Nadu, distributed over 30 years (1985 to 2014). The effect of various non-genetic factors including the period of birth, season of birth, period of calving, season of calving and parity were analyzed through least-squares analyses using univariate general linear model. The different (co)variance components for calculation of genetic parameters were estimated using restricted maximum likelihood method by fitting an animal model.Results:The overall least-squares means (±standard error) of age at first service, age at first calving, weight at first calving, service period, calving interval, dry period, and number of services per conception were 848.06±9.72 days, 1204±12.20 days, 289.81±1.71 kg, 210.01±6.41 days, 489.12±6.45 days, 137.96±5.58 days, 2.50±0.07, respectively. Period of calving had either significant (p<0.05) or highly significant (p<0.01) effect on all reproduction traits studied except service period, calving interval, and dry period. Number of services per conception was affected by season of calving. Parity had significant influence (p<0.05) or highly significant (p<0.01) influence on all the traits studied except service period and dry period. Heritability estimates of age at first service, age at first calving, weight at first calving, service period, calving interval, dry period, and number of services per conception were 0.299, 0.220, 0.017, 0.142, 0.222, 0.177, and 0.042, respectively. The estimates of repeatability for service period, calving interval, dry period, and number of services per conception were 0.219, 0.234, 0.420, and 0.001, respectively.Conclusions:The reproduction performances of Jersey × Red Sindhi crossbreds were lower when compared to the earlier reports on Jersey crossbreds. Heritability and repeatability values were also low to moderate, indicating limited scope for improvement through selection.

The present study aimed to document the seasonal variations in the testicular morphology of the adult guinea fowl (Numida meleagris) under tropical savannah climate of India. The study was conducted in 24 adult healthy guinea cocks. The testes were ovoid in shape throughout the year. The consistency of the testes was moderately firm with great resilience and creamy white in colour during summer and monsoon-I whereas soft in consistency and dull white to yellowish tinge in colour during monsoon-II and winter seasons. The testicular weight, length, width, thickness, volume and circumference were higher during summer and monsoon I than the winter and monsoon II seasons. The mean body weight of the birds did not show significant difference among the seasons. The testicular weight, length, width, thickness, volume and circumference were higher during the summer and monsoon I than the winter and least during monsoon II in the current study. The gonadosomatic index (GSI) and paired testicular weight were high and showed no significant difference during the summer and monsoon-I whereas during winter and monsoon-II, the values were low and showed significant difference between them. The diameter of the seminiferous tubules and its lumen, the diameter of the sustentacular cells (Sertoli cells) were much higher during summer and Monsoon I than winter and monsoon II seasons. The percentage area of interstitial cells and the thickness of the testicular capsule appeared less during the summer and monsoon I seasons. The decreased size of seminiferous tubules, increased amount of cellular debris in the tubular lumen, degenerating germ cells and collapse of seminiferous tubules observed during monsoon II and winter in the present study.

Aim: This study aims to evaluate genetic and non-genetic factors influencing semen production potential of Gir bulls. Materials and Methods: Data on semen quantity (n=6911) and quality (n=466) available from January 2011 to December 2018 at BAIF's frozen semen station, Jind, Haryana, India, were utilized for the study. Factors, namely, season of collection, age at collection, and bull (random effect) were studied for their effect on quantitative and qualitative semen traits. Least square means for the traits were obtained using a general linear model. The effect of age within bull for repeatable traits was analyzed using a longitudinal model with age as the control variable. Multivariate analysis using mixed repeatability model equation was utilized to estimate bull effect correlation (genetic + permanent environmental correlation), phenotypic correlations, and repeatability. Results: The overall least square means of ejaculate volume, sperm concentration, total sperms, initial and post-thaw motility, hypo-osmotic swelling test, and acrosome integrity of frozen semen were 6.62±0.03 ml, 1.22±0.01 109/ml, 8.09±0.05 109/ml ejaculate, 75.78±0.001%, 55.92±0.0001%, 55.13±0.005%, and 71.08±0.001%, respectively. The season of the collection showed a significant effect on volume, concentration, total sperm, and initial motility. The performance of bulls was superior in summer season, followed by winter and monsoon. Increase in semen attributes during summer season was due to the effect of lower temperature on sensitive stages of spermatogenesis. Age at collection had a significant effect on all semen traits. Volume and total sperm count showed increasing trend while concentration showed a decreasing trend with an increase in age. Motility and quality traits did not show any particular pattern. Individual bulls showed differences in all the semen performance traits with age. The repeatability of the traits ranged from 0.04 (HOST) to 0.58 (acrosome integrity). Bull effect correlation ranged from –0.73 (initial motility and acrosome integrity) to 0.93 (HOST and acrosome integrity). Conclusion: Individual bulls showed variation in traits measured over age. The result of the study could be utilized in suggesting suitable management plans to achieve the desired profit by improving semen quality in Gir bulls.

DHARANI, P.; KUMARY, S. U.; SUNDARAM, V.; JOSEPH, C. & RAMESH, G.Morphology of the interstitial tissue of active and resting testis of the Guinea fowl. Int. J. Morphol., 35(4):1359Morphol., 35(4): -1362Morphol., 35(4): , 2017. SUMMARY:The morphology of the interstitial tissue of sexually active and resting testis of the guinea fowl were studied. Six adult health birds of active and resting phases of reproductive cycle were used for this study. The interstitial tissue consisted of loose connective tissue, interstitial cells (Leydig cells), few connective cells, blood vessels and adrenergic nerve fibres in the present study in both active and resting testes. The interstitial tissue was compact in sexually active testis whereas, the volume of the tissue was found to be increased in resting testis. The loose connective tissue of the interstitial tissue composed of mainly of collagen fibres and few reticular fibres whereas elastic fibres were absent in both groups studied. The interstitial cells appeared in clusters of a few cells and were relatively less in the active testis than the resting testis. The interstitial cells were pale staining or polygonal cells with euchromatic nuclei with few large lipid droplets in the active testis whereas the cells were flat and highly heterochromatic with numerous small lipid droplets in resting testis. Few macrophages were found only in resting testis. Interstitial cells showed negative reaction to alkaline, acid phosphatases and PAS in both groups studied but positive for lipids. The interstitial tissue was well vascularised with centrally located blood vessels in the active testis whereas the blood vessels were small and inconspicuous in the resting testis. The lymphatic vessels were not identified in both groups studied.