Economic analysis of culling in Vrindavani cows

Culling in Vrindavani cows

Abstract

Culling is an act of identifying and removing a cow from a herd assuming a constant or expanding herd size, replacing the cow with another cow often with a first-lactation heifer. The relevant data was collected based on the observations from the study on female Vrindavani cattle reared at Cattle and Buffalo Farm of Livestock Production and Management, Indian Veterinary Research Institute (IVRI), Izatnagar, Bareilly, Uttar Pradesh. The data was collected for 10 years (1999-2000 to 2009-10). The year wise means for average lactation milk yields (pooled over all lactations) in Vrindavani, selected and culled cows were estimated and used for estimating selection differential (P_s – P), deviation of culled cows (P_c) from herd average (P) and difference between the means of selected cows (Ps ) and the means for culled cows (Pc) were studied. The means for P, P_s and P_c for average per lactation milk yield up to disposal (AVMYL) of Vrindavani ranged from 1470.18 (2000) to 2879.18 kg (2009), 2175.45 (2000) to 3589.47 kg (2007) and 1385.15 (2000) to 2388.34 kg (2008). It has been observed that the range for selection differential (P_s- P) varied from 460.27 (1999) to 1364.38 kg (2007). However, ranges for deviations of culled Vrindavani cows mean from herd average (P – P_c) and from that of selected group (P_s – P_c) ranged from 21.45 (2001) to 491.46 kg (2004) and 522.26 (1999) to 1541.47 kg. The age at completion of first lactation was estimated by adding average age at first calving (AFC) to average first lactation length (TLL1). The age at completion of first lactation and per day milk yield varied from 1177.71 (2000) to 1328.92 d (2007) and 8.15 (1999) to 12.48 kg/d (2004). The range for period in between point of AFC and 24 months of age varied 213.63 (2000) to 307.89 d (2004). The rearing cost of Vrindavani first calvers (up to completion of first lactation) varied from Rs. 69944.42 (2000) to Rs. 79570.22 (2009).