Effects of genetic and environmental factors on pre-weaning and post-weaning growth in West African crossbred sheep

Abstract

Effects of genetic and environmental factors on pre-weaning and post-weaning growth were studied in West African crossbred sheep. Effects of lamb genotype (7/8 Sahelian-1/8 Djallonké, 3/4 Sahelian-1/4 Djallonké and 1/2 Sahelian-1/2 Djallonké; hereafter denoted 7/8Sa, 3/4Sa and 1/2Sa, respectively), parity, type of birth, sex of lamb and year-season of lambing on birth weight, weaning weight, 8-month weight and pre- and post-weaning growth rates were determined. At birth 7/8Sa and 3/4Sa lambs were heavier (p < 0.01) than 1/2Sa lambs. Lambs born to first-parity ewes were lighter (p < 0.01) at birth than lambs of older ewes. At weaning and 8 months of age, lambs born to fourth-parity ewes were heavier (p < 0.05) than those born to ewes of the other parities. Parity did not have any significant effects on pre-weaning growth rate. Lambs born in the rainy season of 2001 were significantly heavier at birth and at 8 months of age than those born in the dry season of 2001/02, but there was no difference between the two groups at weaning. Pre-weaning growth rate was significantly faster in lambs born in the dry season of 2001/02 but the reverse was true for post-weaning growth rate.

Growth performances of Washera sheep under smallholder management systems in Yilmanadensa and Quarit districts, Ethiopia

“…This is in agreement with literature (Mourad et al 2001;Rastogi 2001;Duguma et al 2002;Benyi et al 2006;Tibbo 2006;Gardner et al 2007;Mishra et al 2007;Yilmaz et al 2007). This could be because of the finite capacity of the maternal uterine space to gestate offspring (Gardner et al 2007), as litter size increases individual birth weights decline.…”

“…This is consistent with literature (Awgichew 2000;Duguma et al 2002;Hassen et al 2004;Benyi et al 2006;Tibbo 2006;Gardner et al 2007;Mishra et al 2007;Yilmaz et al 2007;Thiruvenkadan et al 2008). Loos et al (2001) reported the presence of a Y-chromosome and the products of sry gene activation to have sex-specific effects on foetal growth and that males appear to grow faster than respective females in utero.…”

The effect of two housing systems on productive performance of hair-type crossbreed lambs in sub-humid tropics of Mexico

“…Other authors, showed different ADG post-weaning in lambs along the years, attributing this performance to the similarity of environmental conditions during the years evaluated (Hinojosa-Cuéllar et al 2013). Differences between years for the response variables in the current study suggest that environmental conditions, including administrative management, availability of feed resources and climate could be different leading to changes in productive variables (Dixit et al 2001;Benyi et al 2006;Hinojosa-Cuéllar et al 2013).…”

“…The use of pens with suitable sheds (Caroprese 2008;Rihawi et al 2010;De et al 2015) and same diet throughout the year could explain the results on the productive performance of the lambs. Some studies on grazing lambs (Dixit et al 2001;Benyi et al 2006) in semi-intensive systems (González et al 2002) have found that lambs fattened in seasons which high ambient temperatures showed reduced feed intake, compared to other seasons. The differences between feeding lambs at the indoor system (with concentrate) and grazing lambs suggest that the diet composition has a greater influence on lamb performance than the environmental conditions do (Gabryszuk et al 2014), however, in the present study, lambs received the same diet (concentrate and pasture).…”

Growth and carcass traits of Creole goats under different pre-weaning, fattening and slaughter conditions

“…However, a great phenotypic variability of pre-weaning performances (up to 33% of coefficient of variation) characterises this hardy breed). In the weaner system of production such as in sheep (Villete and Thériez 1981;Benyi et al 2006), pre-weaning performances may influence post weaning abilities; this factor has been included in this study.…”