Energy requirements for the maintenance and growth of Dorper-Jinzhong crossbred ram lambs

Abstract

The sheep industry in China has been rapidly developing in recent years; however, the animals' nutritional requirements under certain conditions have not been thoroughly defined. The objective of this study was to investigate the energy requirements of both the maintenance and growth of Dorper-Jinzhong crossbred ram lambs. Thirty 1/2 Dorper  1/2 Jinzhong crossed F1 ram lambs (35 6 0.5 kg of body weight, BW) were randomly selected and divided into five groups in a randomised design for a comparative slaughter trial. The lambs were offered one type of feed at 100%, 65% and 40% of the ad libitum intake. Another 15 lambs were used for the digestibility trial to estimate the metabolisable energy (ME) values of the diet at various feed intake levels. The net energy for maintenance (NE m ) and the ME requirement for maintenance (ME m ) were 286.68 kJ/kg 0.75 of SBW and 437.80 kJ/kg 0.75 of SBW, respectively; the energy efficiency for maintenance (k m ) was 0.655. The net energy for growth (NE g ) values for varying average daily gain (100-350 g) in ram lambs grown from 35 to 50 kg increased from 1.31 to 5.93 MJ/d with an energy efficiency for growth (k g ) of 0.457. Our results suggest that the energy requirements of Dorper-Jinzhong crossbred ram lambs are lower than the requirements recommended by the National Research Council (NRC) and Agricultural and Food Research Council (AFRC).

Determination of Energy and Protein Requirements of Sheep in Indonesia using a Meta-analytical Approach

“…Metabolizable energy (ME) intake and retained energy (RE) as the change in body energy content of animals are measured through this procedure. The slope of linear regression between RE and ME intake indicates efficiency of ME utilization or ME for gain (Chizzotti et al, 2007;Zhao et al, 2016). Both methods require relatively sophisticated research facilities and financial resources to perform the experiments in which these are among the main obstacles in Indonesia.…”

Requerimientos de energía metabolizable para mantenimiento y ganancia de peso de llamas y alpacas determinados mediante la técnica de sacrificio comparativo

“…La retención de energía (RE) corresponde a la diferencia entre el contenido inicial y final de energía del cuerpo de los animales (Zhao et al, 2016). Los valores se expresaron con relación al peso metabólico (kcal/kg PV 0.75 ).…”

“…En el presente caso, se requieren 9.2 kcal de energía metabolizable por cada gramo de ganancia de peso vivo en llamas, y 11.4 kcal en alpacas. Estos resultados son mucho mayores a los valores reportados para ovinos, caprinos y vacunos (Salah et al, 2014), indicando que las llamas y alpacas alimentadas con dietas de forrajes utilizan mayores cantidades de energía metabolizable por cada unidad de ganancia de peso vivo, evidenciando su menor eficiencia para convertir la energía del alimento en carne, con relación al ovino productor de carne (Zhao et al, 2016).…”

Net micromineral requirements for maintenance and growth of ewe lambs at the latter fattening period

“…Dorper breed is specialized for meat production and is characterized by hardiness, early sexually maturity, rapid growth and excellent meat quality [ 6 ]. To improve growth performance and carcass quality, Dorper sheep have recently been introduced in Shanxi to crossbreed with Jinzhong sheep, and Dorper × Jinzhong crossbreed has become the dominant crossbreed for lamb production in Shanxi [ 7 ]. Nevertheless, the diets formulated for sheep in China are based on information recommended by international committees on animal nutrition.…”

“…Nevertheless, the diets formulated for sheep in China are based on information recommended by international committees on animal nutrition. A recent study of Dorper × Jinzhong crossed ram lambs suggested that energy requirements are lower than the requirements recommended by the National Research Council (NRC) and Agricultural and Food Research Council (AFRC) [ 7 ], and therefore, it is expected that mineral requirements will also vary from AFRC recommendations.…”