Conception rates of estrus-synchronized indigenous Ugandan goats by cervical artificial insemination

Abstract

The conception rates of estrus-synchronized indigenous Ugandan goats with fresh semen cervical artificially inseminated were not known. The study aimed at establishing the effects of synchronization technique, type of semen, age and body condition of does on conception rate. A total of 160 Ugandan indigenous goats were randomly selected from Kabukye and neighboring villages. Does were randomly divided into four equal groups of which; two groups were treated for 17 days with 45 mg progesterone impregnated sponges and the other two groups with Controlled Internal Drug Releasing device (CIDR) containing 3 g progesterone. All does received intramuscular injections of 200 IU Pregnant Mare Serum Gonadotropine (PMSG) at sponge or CIDR removal. During the synchronization period, 2% sponges and 5% CIDR were lost before day 17. Semen was collected from one Boer and one Toggenburg bucks, and was evaluated to ensure that the bucks were fertile. Cervical artificial insemination (AI) was performed at a fixed time (48 and 56 hour) following progestagen withdrawal in (n = 37 sponge and n = 36 CIDR) treated does with fresh Boer semen, and in (n = 40 sponge and n = 36 CIDR) treated does with fresh Toggenburg semen. Pregnancy diagnosis done by observation of non return to estrus from day 17 to 22 post AI indicated that 93 (62.4%) does did not return to estrus. Ultrasound pregnancy diagnosis performed at day 48 post AI revealed conception rate 23 (62.2%) in does treated with sponge, 200IU PMSG, and inseminated using Boer fresh semen; 24 (66.7%) in does treated with CIDR, 200IU PMSG, and inseminated using Boer fresh semen; 27 (67.7%) in does treated with sponge, 200IU PMSG, and inseminated using Toggenburg fresh semen; and 18 (50.0%) in does treated with CIDR, 200IU PMSG, and inseminated using Toggenburg fresh semen. Levels of significances were tested using Chi-square test. There was no significant difference (P = 0.287) between use of sponge and PMSG, 50; (64.9%) or CIDR and PMSG 42; (58.3%) on conception rates. There was no significant difference (P = 0.430) between the bucks which provided semen on conception rate (Boer semen 47 (64.4%) and Toggenburg semen 45 (59.2%). The age determined by the number of pairs of permanent incisor teeth the does had, significantly (P < 0.05) influenced the conception rates across all the age groups. The nutritional status (body condition score measured on a scale of 1 - 5) significantly (P < 0.05) influenced the conception rate. These results indicated that, the use of sponge/PMSG and CIDR/PMSG intra vaginal progestagen treatments are equally efficient in synchronizing estrus in Ugandan indigenous goats. Chi-square test between semen used (P = 0.430), chi-square test between synchronization method (P = 0.287); indicated no significant difference between fertility of the Boer and Toggenburg. The overall fertility results (61.7%) are satisfactory; will increase/improve with experience.