Genetic and Non-genetic Factors Influencing Pre-weaning Growth of Teso Cattle and Their Crosses With Sahiwal and Boran

Abstract

A study was carried out to evaluate key factors affecting pre-weaning performance traits of Teso cattle and their crosses with Sahiwal and Baran at Serere Agricultural and Animal Research Institute, Serere, Uganda. Least squares analysis of variance based on GLM of SAS 2002 was used to analyse the data. The overall mean weights at birth and weaning were l8.36 ± 0.076 and 100.55 ± 0.48 kg, respectively while pre-weaning average daily gains (ADG) were 304 ± 1.96 g/day. Season of birth was a significant (P < 0.00I) source of variation for weaning weight and pre-weaning ADG but not for birth weight. Calves born in the dry season were superior to calves born in the wet season by 0.40 kg, 9.85 kg and 38 g/day at birth, weaning and in pre-weaning ADG, respectively. Weight differences between sexes were only significant (P < 0.05) at weaning where males were heavier than female calves by 3.35 kg. Parity had no significant (P > 0.05) influence on the traits studied. Genetic group· of the calf was a significant (P < 0.00I) source of variation for all growth traits studied. Ranking of genetic groups for weaning weight was similar to that of pre-weaning ADG and were: backcrosses to Sahiwal of F₁ Sahiwal x Teso B₁Sx(SxT)], first crosses of Sahiwal x Teso F₁(SxT)], backcrosses to Teso of F₁ Sahiwal x Teso sires {B_lSxT)xT], backcrosses to Baran of first crosses of Baran x Teso (B₁Sx(SxT)], first crosses of Baran x Teso F₁(BxT)] and Teso cattle. Influence of year of calving was significant (P < 0.0I) for weaning weight and pre-weaning ADG but not for birth weight. Heritability estimates based on sire variance component for birth weight, weaning weight and pre-weaning ADG were 0.41 ± 0.128, 0.02 ± 0.130 and 0.02 ± 0.130 respectively. Heritability estimates based on both the dam and the sire variance components for birth, weaning and pre-weaning ADG were 0.41 ± 0.128, 0.16 ± 0.130 and 0.36 ± 0.130 respectively. It was concluded that first crosses of Baran and Sahiwal have higher pre-weaning growth potential than Teso cattle and F} and backcrosses of Sahiwal breed were superior to Baran crosses.

Keywords: Pre-weaning growth, non-genetic factors, Teso, Sahiwal, Boran, crosses

Tanzania J.Agric.Sc. (2006) VoI.7 No.2, 117 -124