Abstract
The study was conducted to determine the effect of agro-ecological zone, season of birth and sex on Nguni calves’ pre-weaning performance. Production indices such as birth weight (BW), weaning weight (WW), pre-weaning average daily gain (P-ADG) and pre-weaning gain (P-WG) were assessed in the different agro-ecological zones. Herd records on performance of 826 Nguni calves’ from nine Nguni herds representing different agro-ecological zones: arid zone (n = 217); semi-arid zone (n = 296); dry sub-humid zone (n = 118) and humid zone (n = 195) were used for the analysis of pre-weaning calf performance. General linear model (GLM) procedure of SAS (2013) was used to analyse data, whereas mean separation was conducted using Tukey’s HSD test. Agro-ecological zone had a great influence (P < 0.01) on performance levels arising from pasture conditions which were dependent on rain, temperature, topography and soil type. Fluctuations in WW, P-ADG and P-WG performance across agro-ecological zones depicted the sensitivity of Nguni calves’ to postnatal stress. Calves’ in humid zone had higher performance with 121.21 kg for WW, 96.83 kg for P-WG and 0.477 kg/day for P-ADG. The lowest WW (114.51 kg), P-WG (89.98 kg) and P-ADG (0.438 kg/day) were observed in arid zone. Male calves were heavier at weaning (128.18 kg), P-ADG (0.503 kg/day) and total gain (103.03 kg); however, similar BW of 25 kg was observed for both male and female calves. Season had a significant (P < 0.05) effect on BW, P-ADG and P-WG. The P-ADG was 0.461 kg/day for calves born in summer and 0.449 kg/day for calves born in winter season. Calves born in summer gained 94.69 kg and calves born in winter gained 92.10 kg. Summer calves gained 2.59 kg more than winter calves. Summer heifer calves performed poorly whilst summer male calves outperformed heifer calves in terms of WW, P-WG and P-ADG. Pre-weaned calves in humid zone outperformed all calves in other agro-ecological zones. It was concluded that acceptable levels of growth are achievable from Nguni cattle under the different agro-ecological zones of Limpopo province, South Africa.
Highlights
Growth of an animal is influenced by genetic and non-genetic factors (Bourdon 2000)
It was concluded that acceptable levels of growth are achievable from Nguni cattle under the different agro-ecological zones of Limpopo province, South Africa
The study revealed that pre-weaning growth performance of Nguni cattle is dependent on agro-ecological zone factors
Summary
Growth of an animal is influenced by genetic and non-genetic factors (Bourdon 2000). The importance of growth rate in beef cattle production has received ample attention from various researchers (Arthur et al 2001; Lawrence et al 2002). The pre-weaning growth performance of a calf is one of the most important factors for beef productivity (Correa et al 2006). Reduced growth performance is the major limiting factor amongst other factors of cattle production in the tropics (Jones and Hennessy 2000); challenges placed on production traits are mainly environmentally related (DuarteOrtuno et al 1988; Howden et al 1999). Mekonnen and Goshu (1996) reported that traits such as birth and weaning weight as well as growth and survival to weaning have important implications on herd productivity. Reduced growth performance is the major limiting factor amongst other factors of cattle production in the tropics (Jones and Hennessy 2000); challenges placed on production traits are mainly environmentally related (DuarteOrtuno et al 1988; Howden et al 1999). Mekonnen and Goshu (1996) reported that traits such as birth and weaning weight as well as growth and survival to weaning have important implications on herd productivity.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
