ABSTRACT
The absence of formal markets and the large variability of genetic groups and production systems of goats and sheep in developing countries hinder the implementation of traditional breeding programmes. Community-based breeding programmes (CBBP) for these species have been shown to be effective in these countries. In these programmes, the definition of the objectives and criteria of selection is done in a participatory way, which takes into account the desires and needs of the local farmers. We aimed to define the objectives and criteria of a CBBP for goats and sheep in the Inhamuns region, Ceará, Brazil, using a participatory rural appraisal (PRA). This methodology, which consist in an approach that aims to incorporate the knowledge and opinions of rural people in the planning and management of development projects and programmes, was performed in seven districts of two towns of the region (Tauá and Parambu). One hundred twenty-two farmer families participated in the survey. The PRA was able to provide important information, and its results showed that breeders of this region keep flocks of goats and sheep for social, economic and cultural benefits. In order of importance, the main objectives for goat farming were personal fulfilment (PERF), food source for family (FSF), income generation (INCG), savings (SAV) and cultural/family traditions (CULT), while for sheep farming were CULT, FSF, SAV, PERF and INCG. Disease resistance (RDI), adaptability (ADP), fertility (FERT), growth rate (GRA), host resistance of worms (HRW), body conformation (BC), temperament (TEM), longevity (LONG), body size (BSIZ), age at first kidding (AFK) and milk yield (MIY) were the main selection criteria that farmers use for goats. The most important selection criteria used for selecting sheep were ADP, RDI, HRW, GRA, FERT, LONG, BC, BS and age at first lambing. According to these objectives and criteria, the CBBP must consider the adaptation of the animals to the climate and management conditions of the region, the resistance to diseases and productive performance.
Subject(s)
Breeding/methods , Community Participation , Farmers/psychology , Goats , Sheep, Domestic , Adult , Aged , Aged, 80 and over , Animal Husbandry , Animals , Brazil , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
Avaliou-se a influência do DNA mitocondrial sobre características de produção e reprodução em rebanho Gir. Foram analisados, segundo a origem mitocondrial (indicus ou taurus) e linhagem citoplasmática (fêmeas fundadoras), 3385 registros de produção total de leite (PT), produção de leite até os 305 dias de lactação (P305) e de período de lactação (PL); 2394 registros de intervalo de parto (IP) e de produção de leite por dia de intervalo de partos (PIP) e 618 registros de idade ao primeiro parto (IPP). A origem mitocondrial foi incluída no modelo como efeito fixo para a idade ao primeiro parto, por ter, em análise prévia, demonstrado ser significativa somente para essa característica. A estimação dos componentes de variância e parâmetros genéticos bem como a predição dos valores genéticos foram realizadas a partir de dois modelos animais; com e sem a inclusão da variável aleatória, linhagem citoplasmática, com o programa MTDFREML, pelo método da máxima verossimilhança restrita com algoritmo livre de derivadas. A linhagem citoplasmática explicou 1,6 por cento; 1,5 por cento; 1,2 por cento, 0 por cento, 0 por cento e 0 por cento, da variância fenotípica das características PT, P305, PL, IP, PIP e IPP, não obstante não se mostrou significativa no teste de razão de máxima verossimilhança. As correlações de postos entre os valores genéticos obtidos a partir dos modelos com e sem a inclusão da linhagem citoplasmática foram próximas à unidade para todas as características. O modelo que não incluiu a linhagem citoplasmática viesou apenas as tendências genéticas das características PT, P305 e PL. A origem mitocondrial, indicus ou taurus, somente foi significativa (P<0,05) para a variação da idade ao primeiro parto. A linhagem citoplasmática não contribuiu significativamente para a variância fenotípica de quaisquer das características deste estudo.
This study was carried out to evaluate the mitochondrial DNA effect on production and reproduction traits of Gir breed. A total of 3,385 records of milk production (MP), 305-day milk production (305-MP), and lactation length (LL); and 2,394 records of calving interval (CI), milk production per day of calving interval (MPPDCI), and age at first calving (AFC) were analyzed according to mitochondrial DNA origin (indicus or taurus) and cytoplasmatic lineages (foundation cows). The mitochondrial DNA origin was considered as fixed effect for age at first calving analysis. Genetic parameter estimates and predicted breeding values were obtained by restricted maximum likelihood derivative free algorithm using two different animal models (including or not cytoplasmatic lineage effect). Maximum likelihood ratio test showed a non significant effect of cytoplasmatic lineages on all analyzed traits. Cytoplasmatic lineages accounted not significantly for 1.6 percent, 1.5 percent, 1.2 percent, 0 percent, and 0 percent of the total phenotypic variance of MP, 305-MP, LL, MPPDCI and AFC. Ranks correlation among breeding values from both models were close to one for all analyzed traits. No mitochondrial lineage model biased upward only estimates of genetic trends of MP, 305-MP, and LL traits. Mitochondrial origin (taurus or indicus) significantly accounted (P<0.05) only for total variation of age at first calving. Cytoplasmatic lineages did not account significantly for the phenotypic variation of any of the studied traits.
