Volume 18, n. 1, 2020

Este trabalho teve como objetivo avaliar o desempenho produtivo e reprodutivo, aspectos sanitários e comportamentais de coelhas e desempenho produtivo de láparos em crescimento. Foram utilizadas 27 reprodutrizes sendo nove da raça Nova Zelândia Branca, nove da raça Botucatu e nove mestiças. Foram considerados três ciclos produtivos. Para medir a taxa de mortalidade, foram utilizados 451 láparos provindos de 62 partos. Para avaliar o desempenho produtivo (32 a 67 dias), foram utilizados 192 coelhos em crescimento, considerando os três grupos genéticos. De maneira geral, os resultados mostraram que as reprodutrizes da raça Nova Zelândia necessitam de menor número de inseminações para obter prenhes positiva, embora apresentassem láparos mais leves durante a lactação e crescimento. A raça Botucatu se destacou pelo elevado peso de seus filhotes durante a lactação e crescimento e sua elevada taxa de eliminação de reprodutrizes necessita ser confirmada. As coelhas mestiças proporcionaram maior número de partos e filhotes desmamados, além de uma maior capacidade de ingestão de ração. Apesar de não haver diferenças no consumo de ração e na conversão alimentar após o desmame, os coelhos Botucatu e mestiços foram mais pesados aos 18, 32 e 67 dias de idade, apresentando também melhor ganho de peso diário. Além disso, os coelhos destes genótipos citados anteriormente apresentaram menor taxa de mortalidade pré-desmame. O uso de coelhas mestiças provindas das raças Nova Zelândia Branca e Botucatu é indicado para as granjas brasileiras. São necessários novos estudos que avaliem a longevidade e alternativas para reduzir a mortalidade pré-desmame em condições brasileiras.

In developing countries, animal production is affected by the dependence on conventional ingredients or by its high cost, for which it is important to research agro-industrial by-products. Therefore, the purpose to this study was to evaluate the digestibility of diets for rabbits with sweet potato vines, in substitution to alfalfa hay. A biological essay was conducted to determine sweet potato vines digestibility, which took 12 days (5 for adaptation and 7 for collecting feces). A total of 27 rabbits received three different diets: reference (0SPV) and the ones with substitution of 10% (10SPV) and 15% (15SPV) of alfalfa hay for sweet potato vines. The coefficients of digestibility of dry matter were 51.47% (0SPV), 52.07% (10SPV) and 57.41% (15SPV); coefficients of digestibility of mineral matter, 15.17% (0SPV), 17.06% (10SPV) and 16.47% (15SPV); coefficients of digestibility of crude protein, 87.51% (0SPV), 84% (10SPV) and 83.79% (15SPV); coefficients of digestibility of neutral detergent fiber, 20.25% (0SPV), 19.65% (10SPV) and 24.48% (15SPV); coefficients of digestibility of acid detergent fiber, 16.06% (0SPV), 16.82% (10SPV) and 22.36% (15SPV). The conclusion is that sweet potato vines can replace at least 15% of alfalfa hay in growing meat rabbits diets.

Brazilian rabbit breeding plays an important social role through family farming. However, one of the challenges faced is the need for new genetic material from genetically improved rabbits. The artificial insemination (AI) technique in Brazil is restricted to the use of fresh or chilled semen. Hence, this is the first report of the use of frozen semen and live kits in Brazil and probably in Latin America. The aims were to evaluate the commercial viability of frozen rabbit semen in Brazil, ranging from cryopreservation to insemination. Three bucks and three rabbit does of Flemish giant rabbits were used. Semen was collected, evaluated and diluted for freezing with CUNIFreeze. Semen was frozen in a 0.5 mL straw, thawed and then filled in a blue curve rabbit AI sheath with the doe in dorsal position with ovulation induced at the same time with buserelin acetate. The ejaculate volume was 0.8 ± 0.8 mL; the mass motility was 3.3 ± 0.6; and the total motility and vigor after dilution were 65% ± 5 points and 3.7 ± 0.6, respectively. Post-thawed, the motility and vigor were 20% ± 10 and 3,0 ± 0,0, respectively. The pregnancy rate was 66.6% with a litter sizes of 5 and 2 kits. Even with a lower result of litter size compared with refrigerated semen, this report brings a new scenario for rabbit breeding in Brazil, showing that frozen semen is a feasible technique for biobanking and mainly bringing the possibility of imported semen from genetically improved bucks solving inbreeding problems.