Vitamin E supplementation of undernourished ewes pre- and post-lambing reduces weight loss of ewes and increases weight of lambs.

The aim of this study was to test if vitamin E supplementation during late gestation and early lactation would affect the weight of ewes under nutritional restriction and the performance of their lambs. Mature Rambouillet ewes (n = 37) were fed a diet that supplied 70 % of the energy and 80 % of recommended protein requirements and randomly assigned to either vitamin E (vit E, n = 20, 4 IU of α-tocopherol kg(-1) of live weight) or control (n = 17, without vitamin E supplementation). During the experimental period, the mean weight of ewes decreased from 74.6 ± 2.4 to 58.1 ± 2.2 kg. Weight loss of ewes was slightly less for the vit E than the control (-65 vs -124 g day(-1), SEM = 46; P = 0.07). Lambs born from vit E-supplemented ewes were heavier than lambs from the control and grew significantly faster (239 vs 195 g day(-1), SEM = 29.3, P < 0.05) with heavier weights at weaning (16.5 vs 13.5 kg, SEM = 1.8, P < 0.05). Besides, birth weight, weaning weight and daily weight gain favoured to single lambs and to male lambs (P < 0.05). Weaning weight was positively correlated to birth weight (P < 0.05) and weight gain (P < 0.001). When the nutrient requirements for ewes are not met, supplementation of vitamin E during late gestation and early lactation might be an effective strategy to minimise ewe weight loss as well as to increase lamb growth.

Efectos de la inclusión de un concentrado de proteína de soya y dos fuentes de energía en el substituto de leche en el comportamiento productivo de cabritos nubios / Effect of a soy protein concetrate and two energy sources as milk substitutes on productive performance nubian kids

El objetivo de este trabajo fue evaluar la inclusión de un concentrado de proteína de soya y dos fuentes de energía en el substituto de leche sobre el comportamiento productivo de cabritos Nubios desde el nacimiento hasta el destete, manejados en la Unidad Caprina de la Facultad de Agronomía, Universidad Autónoma de San Luis Potosí, México. Se utilizaron sesenta y ocho cabritos (35 hembras y 33 machos) asignados de manera aleatoria a los tratamientos: T1: proteína láctea + sebo de res, T1: 20,0 por ciento de concentrado de proteína de soya + sebo de res, T1: 40,0 por ciento de concentrado de proteína de soya + sebo de res, T1: proteína láctea + sebo de puerco, T1: 20,0 por ciento de concentrado de proteína de soya + sebo de puerco y, T1: 40,0 por ciento de concentrado de proteína de soya + sebo de puerco. El concentrado de proteína de soya no afectó (P>0,05) el consumo de dieta líquida ni la ganancia diaria de peso promedio, pero afectó significativamente (P<0,05) el consumo de concentrado de iniciación (95;95 y 97 g d-¹ animal-¹). Las fuentes de energía no afectaron (P>0,05) el consumo de la dieta líquida ni la ganancia diaria de peso promedio, pero afectaron (P<0,05) el consumo de concentrado de iniciación (97 vs 95 g d-¹ animal-¹). El sexo de los cabritosno afectó (P>0,05) el consumo del substituto de leche ni la ganancia diaria de peso promedio, pero si afectó (P<0,05) el consumo de concentrado de iniciación (100 vs. 92 g d-1animal-1para machos y hembras, respectivamente). El periodo experimental (semanas) afectó significativamente (P<0,05) todas las variables. Los niveles de concentrado de proteína de soya, fuentes de energía y sexo de la cría no afectaron (P>0,05) la conversión de alimento en base a sólidos totales de la leche. Se presentaron algunas interacciones significativas (P<0,05) en el consumo de substituto de leche y concentrado de iniciación.

The objective of this work was to evaluate the inclusion of a concentrate of soy protein and two energy sources as milk substitutes on productive performance of Nubian kids from birth to weaning, managed at the Goat Unit of the Faculty of Agronomy, Universidad Autónoma de San Luis Potosí, México. Sixty eight kids (35 females and 33 males) were randomly assigned to the treatments: T1 : lactic protein + cow lard, T2 : 20.0% of concentrate of soy protein + cow lard, T3 : 40.0% of concentrate of soy protein + cow lard, T4 : lactic protein + pork lard, T5 : 20.0% concentrate of soy protein + pork lard and, T6 : 40.0% of concentrate of soy protein + pork lard. The concentrate of soy protein did not affect (P>0.05) neither the consumption of liquid diet nor average daily weight gain, but it affected (P<0.05) consumption of the starting concentrate (95; 95, and 97 g d-¹ animal-¹). The energy sources did not affect (P>0.05) neither consumption of the liquid diet nor average daily weight gain, but they affected (P<0.05) consumption of the starting concentrate (97 vs 95 g d-¹ animal-¹). Sex of kid did not affect (P>0.05) neither consumption of the milk substitute nor average daily weight gain, but it affected (P<0.05) consumption of the starting concentrate (100 vs 92 g d-¹ animal-¹ for males and females, respectively). The experimental period (weeks) affected (P<0.05) all variables. The levels of the concentrate of soy protein, energy sources, and sex of kids did not affect (P>0.05) feed conversion based on milk total solids. There were some significant interactions (P<0.05) on consumption of the milk substitute and starting concentrate. It is concluded that it is possible to raise kids with milk substitutes prepared with a concentrate of soy protein, cow and/or pork lard.