Crossbreeding of German Brown x N’dama Cattle at Ibadan – I - Mortality Patterns of German Brown, N’dama, and Their Crossbreds
I. C. Nwosu *
Department of Animal/Fisheries Science and Management, Faculty of Agriculture and Natural Resources Management, Enugu State University of Science and Technology (ESUT), Enugu, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
A crossbreeding programme between purebred German brown and N’dama was carried out at the University of Ibadan Teaching and Research farm between 1978 – 1985. The mortality records of 344 purebred German Brown, N’dama, and their crossbreds were examined involving purebred German brown (GBP), purebred N’dama (NDL), 75% N’dama-bred, 50% N’dama-bred, 37.5% N’dama-bred and 25% N’dama-bred based on the level of N’dama gene inheritance. Chi-square and the least square means and analysis of variance procedure for unequal subclass number as outlined by SAS (1990) was used in the analysis. Average mortality rates between 1978 – 1985 showed that the mortality rate significantly (P<0.05) increased from low to high with increasing exotic inheritance; NDB1 had 7.17%, GBND had 13.14% which were significantly (P<0.05) better than GBB2 with 28.4% and GBB1 with 30.13% and even the purebred NDL with 22.13% mortality rates. The purebred GBL died most with 37.04%. The results suggest that crossbreds of higher exotic gene inheritance (GBB1 and GBB2) died more than crossbreds of lower exotic inheritance (NDB1 and GBND). Hence, adaptability to the local environment was better with increased gene proportion of the crossbreds to the indigenous N’dama cattle.
Keywords: Mortality rate, purebred genotypes, crossbred genotypes