Udder Measurements and Their Relationship with Milk Yield in Pelibuey Ewes.

Darwin Arcos-Álvarez,Fernando Casanova-Lugo,Ángel Piñeiro-Vazquez,Manuel Gonzalez-Ronquillo,Luis Sarmiento-Franco,Alfonso Chay-Canul,Ricardo García-Herrera,Jorge Canul-Solís,Luis O Tedeschi

doi:10.3390/ani10030518

Abstract

Simple SummaryThe Pelibuey sheep is considered the main maternal breed in the tropical production systems in Mexico. Nonetheless, there are few studies related to milk production and composition. The quantification of milk production in sheep is important because milk is the main source of nutrients for the growth, development and health of lambs. However, in hair sheep breeds, milking is very difficult due to the small size of their teats. Hence, it is important to evaluate indirect methods to estimate the milk yield in Pelibuey ewes to optimize the growth and to develop management strategies for the lambs.The study aimed to evaluate the relationship between udder measurements and milk yield (MY) in dairy Pelibuey ewes. Udder measurements were taken twice a week for eight weeks before (initial) and after (final) milking, including udder depth (UD), udder circumference (UC), udder width (UW), teat length (TL) and teat diameter (TD) in 38 multiparous ewes. Additionally, udder volume (UV) and the difference (VDF) between initial UV (UVi) and final (UVf) was calculated as VDF = UVi − UVf. The MY varied from 0.10 kg/d to 1.04 kg/d, with a mean of 0.39 kg/d, ± 0.18 kg/d. Initial UC (UCi) ranged from 25.80 cm to 53.30 cm, and VDF varied from 1 cm3 to 2418 cm3. The TL and TD were not correlated with MY (p > 0.05), while UCi, UVi and VDF were positively correlated with MY (p < 0.0001; r = from 0.66 to 0.74). For the prediction of MY, the obtained equations had an r2 ranging from 0.54 to 0.63. The UCi, UDf, UWi and UWf were included in these models (p < 0.05). It is concluded that there was an acceptable correlation (r = 0.60) between the measurements of the udder, the volume of the udder and the daily milk yield in Pelibuey sheep. When direct measurements of milk production cannot be performed in practice, the measurement of udders and their volume could be a viable alternative to estimate milk yield production as an indirect method.

Highlights

In the tropical regions of Latin America, sheep production systems are characterised by the use of animal genetic resources of native creole breeds, mainly hair sheep breeds [1]
Pelibuey ewes of differing body condition scores (BCS) on a scale of 1–5 were selected from a commercial farm, with a score of 1 indicating very thin and 5 obese [19]
The UCi and the volume (UV) and the difference (VDF) widely ranged from 25.80 cm to 53.30 cm and from 1.030 cm3 to 2418 cm3, respectively

Summary

Introduction

In the tropical regions of Latin America, sheep production systems are characterised by the use of animal genetic resources of native creole breeds, mainly hair sheep breeds [1]. In Mexico, the most common sheep breeds used in order of importance are the Pelibuey, Black Belly, Katahdin and Dorper breeds [1]. To date, few studies have evaluated these aspects in Pelibuey ewes and their crosses with Katahdin under tropical conditions in Mexico [4,5,6]. The quantification of milk production in sheep is important because milk is the main source of nutrients for the growth, development and health of lambs. If milk production is insufficient, the growth of lambs could be hampered [6,7,8] For this reason, it is necessary to know the milk production in order to propose, if necessary, economically viable and profitable intervention strategies to increase milk production

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