Reproductive characteristics of native bucks at different ages

This study was devoted to evaluate reproductive parameters in native Egyptian bucks. Attention was also directed to evaluate variation of plasma testosterone levels and semen quality as well as correlate between the influence of age and physical body status [body weight, height, crown rump "CR" length and girth] as well as testis length and width in addition to scrotum circumference "SC" of bucks and their reproductive performance. Semen was collected twice a week for 12 successive weeks during the spring season 2006. Semen volume, sperm concentration, mass and progressive forward motility, percentage of live sperm in addition to percent of abnormal sperm as well as total number of live-normal sperm were also evaluated. The obtained data showed that semen volume, sperm motility, percent of live sperm and abnormal sperm, testicular size, scrotum circumferences, libido and testosterone hormone differed significantly [P <0.002] in bucks according to changes in physical conditions. Therefore, it was concluded from the present study that the optimal native bucks expected to be used for either natural service or artificial insemination should be of age >/= 2 years, body weight >/= 35.83 kg, CR >/= 63.16 cm, testis length >/= 12.40 cm, testis width >/= 5.30 cm, SC >/= 22.50 cm, body height > /=70.83 cm, girth >/= 75.33 cm, libido index [MPD] >/= 2.66 concomitant with serum testosterone level >/= 2.30 ng/ml

Effect of recombinant somatotropin with or without PMSG on postpartum multiparous buffalo in Egypt

This study was carried out on ten Egyptian female multi parous buffaloes suffering from prolonged postpartum period with no estrous signs and low serum progesterone level. Animals were randomly divided into two groups. Females in both groups were injected subcutaneously with 500 mg recombinant bovine somatotropin "rbST",one group received a single intramuscular dose of PMSG [2000 i.u.] 7 days later. Blood samples were collected one week before treatment and for four consecutive weeks after treatment. The levels of progesterone, insulin-like growth factor- 1[IGF-1] and total cholesterol were analysed. Injection of rbST with or without PMSG elevated serum level of IGF-1 for the first two weeks post-injection then declined during the 3rd and 4th weeks compared to pretreatment levels. Both serum progesterone and total cholesterol levels increased throughout the 4 weeks post-injection as compared with their corresponding control values before treatments. In addition, rbST increased milk yield significantly as well as motivated the females to resume cyclic activity of the ovaries [4 / 5 in animals treated with rbST plus PMSG and 3/5 in those treated with rbST alone]. The conception percent improved