Dairy cattle

Genomic analysis of body weight in smallholder crossbred dairy cows in India, based on using linear body measurements

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Abstract

Body weight (BW) is a key determinant of production efficiency in smallholder environments where feed suppl severely limits production. The objective of this study was to conduct the first genomic evaluation of BW in smallholder crossbred dairy cows in India, using body length and chest girth measurements in the absence of a structured genetic testing program. Linear measurements were collected from crossbred cows across 13 Indian states under the BAIF Development Program. After extensive data cleaning and quality control, 189,762 BW records from 29,993 cows were retained. Genetic analyses were performed on 16,230 genotyped and non-genotyped cows with 129,049 records using a repeatability animal model implemented in Wombat. Fixed effects included parity, production environment (ENV; high, medium, low, derived from herd and centre milk yield-based estimates), and quadratic effects of days in milk (DIM) within each ENV. Random effects included additive genetic, herd, season-by-centre, and permanent environmental components. Breed composition of Holstein Friesian (HF) and Jersey ancestry was estimated using ADMIXTURE, and their interaction with ENV was fitted to test breed by environment effects on BW. The heritability estimate of a single BW record was 0.173 (s.e. = 0.021). Mean BW differed significantly (P < 0.01) among environments: 398.9 kg (high), 361.3 kg (medium), and 310.0 kg (low). In low environment, BW increased with increasing HF proportion, while little variation was observed in high environments. Within environments, BW varied only slightly across lactation (7 kg for high and medium ENV, and 3 kg for low ENV), indicating that linear measurements are less sensitive for tracking short-term BW changes caused by nutrition or pregnancy but may better reflect overall growth or mature size.

Keywords: 2026

How to Cite:

Al Kalaldeh, M., Swaminathan, M., Bhave, K., Jadhav, S., Gaundare, Y., Potdar, V., Shinde, S., Joshi, A., Dhanikachalam, V., Shirsath, T., Punde, N., Costilla, R., Hayes, B. & Gibson, J., (2026) “Genomic analysis of body weight in smallholder crossbred dairy cows in India, based on using linear body measurements”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286401. doi: https://doi.org/10.31274/wcgalp.23985

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