SYNCHRONIZATION OF ESTRUS IN NUBIAN GOATS

In a randomized block design, 34 Nubian goats were allocated for the p urpose of studying the efficiency of different hormonal treatments in inducing and synchronizing oestrus, The animals were selected and grou ped according to age so that each age group was represented under each group. The control group (A) consisted of four females while the rest of the groups (each consisting of 10 females) were randomly assigned to three different treatments. These treatments included a double Clop rostenol intramuscular injection (125 mu g) (treatment B); intravagina l sponges impregnated with progesterone (40 mg) inserted for a 16-day period (treatment C) and treatment C plus an intramuscular injection o f pregnant mare serum (300 IU) two days before sponge removal (treatme nt D). A vasectomized and a spermatic buck was introduced to all group s immediately after termination of each treatment for detection of oes trus. Does were monitored for the time interval from end of treatment to the onset of oestrus, oestrous signs and the duration of oestrus. T hey were then artificially inseminated at 24 and 48 h following termin ation of treatments, Those returning to oestrus were handmated. The co ntrol group was handmated. Conception rates were determined by non-ret urn rates and by radioimmunoassay (RIA) used to monitor serum progeste rone concentration 3-10 weeks after insemination. Late pregnancy was d iagnosed by abdominal palpation after Day 90-110. The obtained results indicated that all the employed treatments were capable of inducing a nd synchronizing oestrus in Sudanese Nubian goats. Treatment B was sig nificantly (P<0.05) more efficient than the other two treatments. The percentage of does responding to treatment B by showing oestrus was 10 0%, followed by D (77.7%) and C (70%). Duration of the induced oestrou s period was shortest (P<0.05) in treatment C (38.6+/-7.1 h) followed by D (52+/-7.8 h) and B (52.6+/-4.8 h), Pregnancy rates were higher (P <0.05) with treatment B (77.8%) followed by C (70%) and D (55.5%). The overall pregnancy rate diagnosed by RIA was 37.5% less than that diag nosed by abdominal palpation (64%). However, kidding confirmed the acc uracy of RIA as a pregnancy diagnosis. (C) 1998 Elsevier Science B.V. All rights reserved.