Nader Drbas
General Commission for Scientific Agricultural Research-
al-Ghab Research Center
Damascus University, Faculty of Agriculture
2009

Abstract

This study was conducted at Buffalo Research Station in Shatha, Administration of Livestock Research during 2005 to 2008.
Ten growing Syrian males buffalo with age 5.5-6 months were used to measure body weight (BW), the growth rate of testicular dimensions: length, TL; diameter, TD; circumference, TC) and testis size, hormonal concentration: (Testosterone,T; Luteinizing hormone, LH), and  testicular histology as parameters to determine the puberty age. Blood samples were collected every 15 days from the jugular vein to measure Ts and LH, while BW, TL TD, TC and testis size, and testicular sections were measured monthly for 16.5 months.
A balance with accuracy of 0.5 kg/1000kg was used to weigh the animals and a caliper was used to measure TL and TD while the circumference was measured with a cotton thread fitted and transcribed on a ruler and graduate container was used to measure testis size. The concentrations of Ts and LH were measured using Enzyme Linked Immune Sorbent Assay (ELISA). Testicular sections were made using a Leica microtome and stained slides were prepared using different stains and fixed with balsam Canada.
The results indicated highly significant differences (p <0.05) for all the parameters in studied animals, with a progressive increase in hormonal levels and testicular dimension’s with respect to the advancing age of studied growing males buffalo. Similar changes were observed in the left and right testis. The highest relative rate of change in the average of most studied parameters and spermatozoa appeared in the lumen of somniferous tubules were observed when growing males buffalo reached 16 months old with an average BW of 314 ± 14.1 kg. These changes were shown to be 276, 195, 186, and 467%, in BW, TL, TC, Ts and testis size respectively, while 815 and 153% in T and LH respectively. Data on studied parameters (except T and LH) was progressively through the year in studied animals.
Positive significant correlations (r = 0.94 to 0.98, P<0.01) among testicular dimensions, and testis size, and between each of them and the body weight (r = 0. 83 to 0.92).were found. There was also a positive correlation between the dimensions, and testis size, with the advancement age of animal (r = 0.75 to 0.86), and according to these correlations, mathematical equations were found to predict the testicular dimensions depending on the body weight (kg) and the age ( day) of the animal. Positive correlations (r = 0.22 to 0.34, P<0.01) were also observed with Testosterone and (0.30 to 0.51 P <0.01) with LH hormone.
It was concluded that sexual puberty of Syrian buffalo males occurs at 16 month of age and the year seasons don’t influence it.
Keywords: Syrian Buffalo, Testicular dimensions, reproductive hormones, testicular sections, sexual puberty.