A field study of reproductive performance and productivity of Pelibuey ewes in Southeastern Mexico

Abstract

The objective was to evaluate the reproductive performance and productivity of Pelibuey ewes in two flocks in Southeastern Mexico. Animals grazed on irrigated star grass (Cynodon plectostachyus). In flock 1, lambs grazed with their mothers from 7 to 70 days of age (weaning age), whereas in flock 2, they were confined and offered chopped grass, a commercial concentrated and managed under restricted suckling until weaning at 60 days of age.. The statistical model included the fixed effects of flock, year and season of lambing, parity number, litter size at weaning, first order interactions and the random effects of ewe and the error term. The means ± SD for age at first lambing, prolificacy, lambing interval (LI), weaning weight, and productivity were 477 ± 85.5 days, 1.41 ± 0.51 lambs, 255.9 ± 51.8 days, 16.5 ± 4 kg, and 18.1 ± 4.42 kg of lamb weaned, respectively. Repeatability estimates for the latter four traits were 0.09, 0.07, 0.11, and 0.13, respectively. All main effects in the models were significant (P < 0.001), except for year on LI. Prolificacy and productivity increased with parity number. The shortest LI was in the rainy season. Ewes with two or three lambs produced 8 and 14 kg of lamb more at weaning than single lamb ewes. In conclusion, reproductive performance and productivity could be improved, and the low repeatability estimates suggest that management should be used in a short term rather than genetic approaches.

A note on the changes in the preweaning growth of Pelibuey lambs

“…Single litters showed lower weight (P < 0.05) at birth and at 60 days when compared to multiple litters (table 5), which is consistent with the weight reported for hair sheep (Magaña-Monforte et al 2013, Hinojosa-Cuellar et al 2015.…”

“…In breeding sheep different physiological processes such as conception, gestation and lactation determine the level of productivity during their stay in a flock (Magaña-Monforte et al 2013). Particularly, the number of lambs during the lactation period is crucial, since it is during this stage where the highest mortality occurs (Nava-Lopez et al 2006, Macedo et al 2010.…”

Ewe and lamb pre-weaning performance of Pelibuey and Katahdin hair sheep breeds under humid tropical conditions

“…Pelibuey, is the most predominantly hair sheep breed in Mexico because its adaptability to a broad range of environmental factors (Mac ıas-Cruz et al 2012;Chay-Canul et al 2016). Rusticity, nonseasonality of reproduction, prolificacy and parasite tolerance are some of the referred favourable traits associated to this breed (Mac ıas-Cruz et al 2012;Magaña-Monforte et al 2013;Chay-Canul et al 2016). On the other hand, Katahdin was introduced from the United States during the 2000's (S anchez-D avila et al 2015).…”

Environmental effects on productive and reproductive performance of Pelibuey ewes in Southeastern México

“…Reproductive and productive traits of the ewe have important contribution to the biological efficiency and profitability of the production system (Rubianes & Ungerfeld 2002). These traits are influenced by genetic and environmental factors (Wildeus 1997;Magaña-Monforte et al 2013), so the knowledge of its effects is important in order to identify and plan sound management to improve the ewe Pelibuey performance. However, this breed is not used to its fullest potential, because farmers do not consider the environmental and management factors that could improve the reproductive and productive performance of ewes.…”