Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa.
Directorate: Animal Sciences, Department of Agriculture, Western Cape Government, Private Bag X1, Elsenburg, 7607, South Africa.
Trop Anim Health Prod. 2023 Sep 23;55(5):319. doi: 10.1007/s11250-023-03731-z.
Access to simple, accurate feed intake models would facilitate decision-making in feedlots as feed costs are a major part of operational expenditure. This study aimed to develop genotype-specific feed intake models for South African feedlot lambs. Four ram and four ewe lambs each of eight genotypes were raised under ideal growth conditions from weaning until 1 year of age. Feed intake and growth were monitored throughout this period. The intake data were then used to fit various models to predict daily feed intake, intake as percentage of body weight, cumulative intake and feed conversion ratio. No satisfactory univariate models could be found for the prediction of daily or percentage intake, but a good fit was found for cumulative intake data (R >0.80, P <0.01). The slope parameters of these linear models show a strong correlation (72%) with feed conversion and can therefore also serve as proxies for feed conversion. A model was also developed that can predict feed conversion ratio with a moderate accuracy (R =0.5, P <0.05) at a given body weight. The cumulative intake model was deemed accurate and simple enough for practical use.
获取简单、准确的采食量模型将有助于饲养场做出决策，因为饲料成本是运营支出的主要部分。本研究旨在为南非育肥羔羊开发特定基因型的采食量模型。从断奶到 1 岁，每个 8 个基因型的 4 个公羊和 4 个母羊都在理想的生长条件下饲养。在此期间监测采食量和生长情况。然后，将摄入数据用于拟合各种模型，以预测每日采食量、采食量占体重的百分比、累积采食量和饲料转化率。无法找到用于预测每日或百分比摄入量的令人满意的单变量模型，但对于累积摄入量数据拟合度很好（R >0.80，P <0.01）。这些线性模型的斜率参数与饲料转化率有很强的相关性（72%），因此也可以作为饲料转化率的替代指标。还开发了一种模型，可以在给定体重下以中等精度（R =0.5，P <0.05）预测饲料转化率。累积摄入量模型被认为足够准确和简单，可用于实际应用。
