Portal de Pesquisa da BVS Veterinária

Tese em Português | VETTESES | ID: vtt-215772

Resumo

Objetivou-se com este estudo avaliar os principais fatores nao geneticos que influenciam na taxa de sobrevivencia de cordeiros e cabritos de diferentes grupos geneticos em um sistema semi-intensivo de producao no semiarido brasileiro. O estudo foi desenvolvido em dois sistemas de producao, um de ovinos e outro de caprinos. O delineamento experimental foi o inteiramente casualizado. A sobrevivencia dos cordeiros e dos cabritos ate o desmame, foi avaliada por meio do procedimento GLM do pacote estatistico SAS (2009), ajustando-se a um modelo estatistico. As analises de variancia (ANOVA) foram realizadas por meio da metodologia dos Quadrados Minimos. Quando observada significancia dos diferentes efeitos incluidos nos modelos, as medias foram comparadas por meio de procedimento de comparacao multipla, com o teste de Duncan, considerando nivel de probabilidade de 5%. No primeiro ensaio foram utilizados registros de dados do rebanho ovino da Estacao Experimental Benjamim Maranhao- EEBM, EMEPA, localizada na Mesorregiao do Agreste paraibano, no Municipio de Tacima- PB. Foram utilizados registros de nascimentos de 570 cordeiros, sendo esses da raca Santa Ines e mesticos Dorper x Santa Ines. As matrizes foram submetidas a um manejo reprodutivo que lhe proporcionasse tres partos em dois anos. A media geral de sobrevivencia dos cordeiros ate o desmame foi de 84,56%. Os ciclos reprodutivos e o sexo dos cordeiros nao influenciaram a sobrevivencia dos cordeiros ate o desmame. Cordeiros nascidos com peso 2 kg foram os que tiveram as menores taxas de sobrevivencia (38,09%) ate o desmame. Cordeiros nascidos de ovelhas com escore de condicao corporal de 1,5 tiveram menores taxas de sobrevivencia, diferindo dos cordeiros nascidos de ovelhas com ECC >2. O grupo genetico dos cordeiros influenciou as taxas de sobrevivencia, sendo, cordeiros mesticos os que apresentaram maiores taxas de sobrevivencia, com destaque para os cordeiros 34 Dorper x 14 Santa Ines (95,31%) e a menor taxa de sobrevivencia foram encontradas nos cordeiros Santa Ines puros (74,28%). Os cordeiros nascidos de parto simples tiveram as maiores taxas de sobrevivencia (90,41%), diferindo dos cordeiros de nascimentos multiplos (80,91%). No segundo experimento foram utilizados dados provenientes de um rebanho caprinos, da Estacao Experimental Pendencias EEP, EMEPA, localizada no Cariri Oriental paraibano, municipio de Soledade PB. Para o desenvolvimento da pesquisa foram utilizados registros de nascimentos de 483 cabritos mesticos da raca Boer e da raca Savana. As matrizes foram submetidas a um manejo reprodutivo que lhe proporcionasse tres partos em dois anos. A media geral de sobrevivencia dos cabritos foi de 95,83%. A epoca e ano de nascimento dos cabritos influenciou a sobrevivencia nos ciclos produtivos, sendo que, cabritos nascidos no quarto ciclo produtivo tiveram as menores taxas de sobrevivencia (86,17%), em relacao aos cabritos nascidos no primeiro ciclo produtivo (98,69%). Cabritos nascidos com peso 2 kg foram os que tiveram as menores taxas de sobrevivencia (78,78%). Os efeitos de escore de condicao corporal da matriz ao parto, o grupo genetico das crias e o tipo de nascimento nao influenciaram a taxa de sobrevivencia ate o desmame dos cabritos, no presente estudo. O uso de fatores nao geneticos pode ser utilizado para avaliar a taxa de sobrevivencia dos rebanhos de ovinos e caprinos, como tambem servir como ferramenta para reduzir os indices de mortalidade nos primeiros dias de vidas das crias.

---

The objective of this study was to evaluate the main non-genetic factors that influence the survival rate of lambs and goats from different genetic groups in a semi-intensive production system in the Brazilian semi-arid region. The study was developed in two production systems, one of sheep and one of goats. The experimental design was completely randomized. The survival of lambs and goats until weaning was evaluated using the GLM procedure of the statistical package SAS (2009), according to a statistical model. Analyzes of variance (ANOVA) were performed using the least squares methodology. When the significance of the different effects included in the models was observed, the averages were compared through a multiple comparison procedure using the Duncan test, considering a 5% probability level. In the first trial, sheep data from the Benjamim Maranhao-EEBM Experimental Station, EMEPA, located in the Meso-region of the Agreste region of Paraiba, in the municipality of Tacima-PB, were used. Birth records of 570 lambs were used, being those of the Santa Ines breed and Dorper x Santa Ines mesticos. The matrices were submitted to a reproductive management that gave three births in two years. The overall survival rate of lambs until weaning was 84.56%. Reproductive cycles and sex of lambs did not influence the survival of lambs until weaning. Lambs born weighing 2 kg were the ones that had the lowest survival rates (38.09%) until weaning. Lambs born to sheep with a body condition score of 1.5 had lower survival rates, differing from lambs born to sheep with ECC> 2. The genetic group of the lambs influenced the survival rates, being that mestizo lambs presented the highest survival rates, especially lambs 34 Dorper x Santa Santa Ines (95.31%) and the lowest survival rate were found in lambs Santa Ines pure (74.28%). Lambs born with single birth had the highest survival rates (90.41%), differing from lambs with multiple births (80.91%). In the second experiment, data from a goat herd were used, from the Pendencias - EEP Experimental Station, EMEPA, located in Cariri Oriental, Paraiba, in the municipality of Soledade - PB. For the development of the research, birth records of 483 crossbred Boer and Savana goats were used. The matrices were submitted to a reproductive management that gave three births in two years. The overall survival rate of goats was 95.83%. The time and year of birth of the goats influenced the survival of the productive cycles, and that the kids born in the fourth productive cycle had the lowest survival rates (86.17%), in relation to the kids born in the first productive cycle (98.69 %). Kids born weighing 2 kg were the ones that had the lowest survival rates (78.78%). The effects of maternal body condition score at calving, calving group, and type of birth did not influence the survival rate until weaning of goats in the present study. The use of non-genetic factors can be used to evaluate the survival rate of ovine and caprine herds, but also serve as a tool to reduce mortality rates in the first days of the offspring's lives.

Biblioteca responsável: BR68.1