MSCAGR (Animal Science) / Department of Animal Science / The aims of the study were to evaluate the effects of dilution and chilled storage time on the quality of semen, and of different artificial insemination techniques on fertility in artificially inseminated indigenous Venda does. Fresh semen was collected using an artificial vagina from three Boer bucks aged 4±1.55 years once every four days during July and August 2016. Semen was pooled and samples were divided into two equal parts, which were extended using Biladyl® extender at ratios of 1:5 and 1:10 v/v (semen to extender), before refrigeration for 120 hours at 5 °C. The fresh undiluted semen and freshly extended semen were evaluated in six replicates for sperm motility, live-dead and sperm morphology using the Sperm Class Analyzer (SCA). Extended semen continued to be evaluated at 24 hour intervals for 120 hours. Ninety indigenous Venda does were obtained from different flocks in the Vhembe district and kept intensively in one 10 m x 40 m pen at the University of Venda experimental farm in the goat feedlot. The does were fed and watered ad libitum. After acclimatization for 14 days, estrus was synchronized using a controlled internal drug release (CIDR) containing 0.3 g of progesterone. Upon removal of the CIDR, does were injected 10 mg of PGF2α (Lutalyse® dinoprost tromethamine) Sterile Solution. At 24 hours after the removal of the CIDR, the does were injected intramuscularly with 300 international units (IU) of equine chorionic gonadotrophin (eCG). Forty eight hours after the removal of the progesterone, freshly collected and diluted (1:5 ratio ~150x106 sperm/ml), five day-stored semen were used to inseminate the does using cervical (CAI), trans-cervical (TAI), and laparoscopic artificial (LAI) insemination methods in a complete randomized design (CRD) with a 2 X 3 factorial arrangement of the treatments with 15 replications per treatment. The does were tested for pregnancy after 30 days using ultrasonography. Analyses of variance was performed on the pregnancy, kidding rates and on prolificacy using the GLM procedure of Minitab (Minitab 2013). Significant differences in all motility parameters were observed between the extension ratios and storage time (P<0.01). There were significant interactions between the extension ratio and storage time (P<0.05) on the sub-population of sperm cells with non-progressive motility (NON-P). Significant (P<0.01) interaction was observed between the semen extension ratio and storage time on medium and slow spermatozoa (P<0.01). The method of insemination did not (P>0.05) affect fertility, though both pregnancy and kidding rates numerically decreased in the order laparoscopic insemination (LAI)≥ trans-cervical insemination (TAI)≥ cervical insemination (CAI). Overall, 71% kidding rate was achieved.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Novas exigÃncias de mercado sÃo estabelecidas e com estas, novos modelos produtivos, com menor impacto ambiental, devem ser adotados para atender as necessidades dos consumidores, sem que resulte em prejuÃzos à produtividade do sistema. Assim, o objetivo deste estudo foi avaliar a eficiÃncia da bioestimulaÃÃo (Efeito Macho) pela taxa de concepÃÃo e pariÃÃo de cabras inseminadas artificialmente com sÃmen fresco. Para tanto, foram avaliadas a taxa de fertilidade e pariÃÃo de 73 cabras, pertencentes ao grupo genÃtico Saanen e seus mestiÃos com Anglonubiano, submetidas à inseminaÃÃo artificial, que tiveram o estro induzido e sincronizado pelo efeito macho. O experimento ocorreu durante os perÃodos chuvoso (marÃo-abril) e seco (agosto-setembro) de 2012. Foram coletados dados referentes Ãs variÃveis climÃticas (TA: temperatura ambiente; e UR: umidade relativa do ar) para o cÃlculo do ITU (Ãndice de temperatura e umidade). Os dados foram submetidos à anÃlise estatÃstica a 5% de probabilidade. O ITU foi mais elevado (P<0,05) para o perÃodo chuvoso, e assumiu valores acima dos ideais para caprinos, apresentando situaÃÃo de emergÃncia para o perÃodo chuvoso, e de perigo para o perÃodo seco. O efeito macho mostrou-se eficiente independente da Ãpoca do ano, resultando em 94,5% cabras em estro. A duraÃÃo do primeiro estro foi semelhante entre o perÃodo chuvoso e seco, com mÃdia geral de 23,4 horas. O intervalo entre inÃcio do efeito macho e manifestaÃÃo do estro de 11 dias, havendo uma maior manifestaÃÃo de estro (primeiro estro) logo na primeira semana para ambos os perÃodos. Em geral, 65% das cabras retornaram em estro, sendo o intervalo entre o inÃcio do efeito macho e a manifestaÃÃo do segundo estro foi maior (P<0,05) para o perÃodo chuvoso (27,8 dias), isto està relacionado ao tipo de ciclo estral, onde houve um maior (P<0,05) nÃmero de ciclos normais (20) para este perÃodo, e um elevado (P<0,05) nÃmero de ciclos curtos (15) para o perÃodo seco. A fertilidade para o perÃodo seco (57,6%) foi proporcionalmente superior ao perÃodo chuvoso (44,4%). No entanto, a taxa de pariÃÃo mostrou uma tendÃncia (P=0,57) a ser superior para o perÃodo seco. Esta menor taxa para o perÃodo chuvoso pode estar relacionado à alta variaÃÃo climÃtica observada durante o perÃodo experimental. Em geral, o segundo estro foi mais propÃcio à resultar em fertilidade, seja para o perÃodo chuvoso ou seco. Com isso, conclui-se que a inseminaÃÃo artificial de cabras com estro induzido e sincronizado pelo uso do efeito macho à um manejo que pode ser empregado para a produÃÃo de caprinos resultando em Ãndices reprodutivos satisfatÃrios. / New market requirements are established and with them, new production models it should be adopted to meet the consumers demands, without resulting in damage to system productivity, with less environmental impact. The aim this study was to evaluate the effectiveness of Male Effect by fertility rate of goats inseminated artificially. Thus, we evaluated the fertility and calving rates of 73 goats belonging to genetic group Saanen and its crossbred. This does had their estrus induced and synchronized by the male effect and it were artificially inseminated with fresh semen. The experiment took place during the rainy (March-April) and dry (August-September) seasons of 2012. We collected data on climatic variables (RT: room temperature; and RH: relative humidity) for calculating the THI (temperature and humidity index). Data were analyzed statistically at 5% probability. The THI was higher (P<0.05) in the rainy season, and it assumed values above ideal for goats, with an emergency situation to the rainy season, and dangerous situation to the dry season. The male effect was effective regardless of season, it resulting in 94.5% of estrus. The duration of the first estrus was same between the rainy and dry season, it had a mean duration of 23.4 hours. The interval between the onset of the male effect and estrus was 11 days, and there was a greater manifestation of estrus (first heat) in the first week for both seasons. Overall, 65 % of goats returned in estrus, it been the interval between the onset of the male effect and second estrus manifestation was greater (P<0.05) during the rainy season (27.8 days). This is related to the estrous cycle length, where there was a greater (P <0.05) number of normal estrus cycles (20) during rainy season, and high (P <0.05) number of short estrus cycles (15) during dry season. The fertility during the dry season (57.6 %) was proportionally greater than rainy season (44.4 %). However, the calving rate showed a trend (P = 0.57) to be higher the dry season. This lower rate during rainy season may be related to high climate variability observed during this experimental period. The second estrus was more like to result in fertility, during rainy or dry season. This indicates that the artificial insemination of goats with induced and synchronized estrus by male effect is a management can be utilized in goat production systems resulting in satisfactory reproductive rates.