Njubi D M, Wakhungu J W, Badamana M S
Department of Animal Production, University of Nairobi, P.O. Box 29053-00625, Nairobi, Kenya.
Trop Anim Health Prod. 2010 Apr;42(4):639-44. doi: 10.1007/s11250-009-9468-7. Epub 2009 Oct 10.
The study is focused on the capability of artificial neural networks (ANNs) to predict next month and first lactation 305-day milk yields (FLMY305) of Kenyan Holstein-Friesian (KHF) dairy cows based on a few available test days (TD) records in early lactation. The developed model was compared with multiple linear regressions (MLR). A total of 39,034 first parity TD records of KHF dairy cows collected over 102 herds were analyzed. Different ANNs were modeled and the best performing number of hidden layers and neurons and training algorithms retained. The best ANN model had one hidden layer of logistic transfer function for all models, but hidden nodes varied from 2 to 7. The R (2) value for ANNs for training, validation, and test data were consistently high showing that the models captured the features accurately. The R (2), r, and root mean square were consistently superior for ANN than MLR but significantly different (p > 0.05). The prediction equation with four variables, i.e., first, second, third, and fourth TD milk yield, gave adequate accuracy (79.0%) in estimating the FLMY305 from TD yield. It emerges from this study that the ANN model can be an alternative for prediction of FLMY305 and monthly TD in KHF.
该研究聚焦于人工神经网络(ANN)基于肯尼亚荷斯坦 - 弗里生(KHF)奶牛泌乳早期少数几个可用的测定日(TD)记录来预测下个月以及头胎305天产奶量(FLMY305)的能力。将所开发的模型与多元线性回归(MLR)进行比较。对从102个牛群收集的总共39,034条KHF奶牛头胎TD记录进行了分析。构建了不同的人工神经网络模型,并保留了表现最佳的隐藏层数、神经元数量和训练算法。最佳的人工神经网络模型对所有模型都有一个具有逻辑传递函数的隐藏层,但隐藏节点数量从2到7不等。人工神经网络用于训练、验证和测试数据的R²值始终很高,表明模型准确地捕捉到了特征。人工神经网络的R²、r和均方根始终优于多元线性回归,但差异显著(p > 0.05)。包含四个变量(即第一次、第二次、第三次和第四次TD产奶量)的预测方程在根据TD产奶量估算FLMY305时具有足够的准确性(79.0%)。从这项研究可以看出,人工神经网络模型可以作为预测KHF奶牛FLMY305和每月TD的一种替代方法。