Predicting the age and weight at puberty of Ongole Grade cattle using nonlinear mathematical model in Kebumen Farmer Association
Abstract: This research is
aimed to evaluate the nonlinear mathematical model in predicting the age and
weight of Kebumen Ongole Grade (PO) cattle at puberty. The data used in this
research was weight recordings of (768) PO cattle, ranging from calf (< 1
month) to adult (60 months), collected by Kebumen PO cattle Breeder Association
(ASPOKEB) from 2013 to 2015. These cattle were reared by a group of farmers
located in six sub-districts: Mirit, Lembu Purwo, Ambal, Puring, Petanahan, and
Klirong in Kebumen district, Jawa Tengah Province. Brody, Bertalanfy, Logistic
and Gompertz mathematical models were used to analyze the data. The analysis
showed that the R2of the four models classify high in the category (R2
>0.70). Mature weight (A) of PO cattle predicted by Logistic (349 kg) and
Gompertz (358 kg) were most appropriate. Out of the four models, the Logistic
model was the most accurate in predicting the weight at puberty (174 kg) of PO
cattle, but all observed cattle are still in the follicular phase.
Keywords: Inflection point;
Mature weight; Logistic; Gompertz; Vaginal smear
Author: D. Maharani, A. H. K.
Amrullah, D. T. Widayati, S. Sumadi, A. Fathoni, M. Khusnudin
Journal Code: jppeternakangg170037