Effects Of Calf Sex, Birth Season, And Dam Age At First Calving On Calf Birth Weight In Anatolian Water Buffaloes Reared In Istanbul Province

• DOI: https://doi.org/10.22533/at.ed.946112621017

• Palavras-chave: Anatolian water buffalo; birth weight; calf sex; environmental factors; season; age at first calving.

• Keywords: Anatolian water buffalo; birth weight; calf sex; environmental factors; season; age at first calving.

• Abstract: This study evaluated the effects of calf sex, birth season, and dam age at first calving (AFC) on calf birth weight (CBW) in Anatolian water buffaloes (AWB) reared in Istanbul Province, Turkiye. A total of 259 complete calf records were analysed using a general linear model (GLM) including the fixed effects of calf sex, birth season, and AFC class, with herd-year included as a blocking factor. Least-square means were compared using Tukey’s HSD test (α = 0.05). Male calves were heavier at birth than female calves (39.71 ± 0.52 vs. 37.51 ± 0.51 kg). Summer-born calves had the highest mean CBW (39.52 ± 0.56 kg), whereas autumn-born calves had the lowest mean CBW (35.85 ± 0.75 kg). CBW also increased with advancing AFC class, indicating the importance of maternal maturity. Phenotypic correlations suggested that CBW was positively associated with AFC and selected lactation-related traits. The results indicate that non-genetic sources of variation should be considered when evaluating birth weight and designing management strategies for Anatolian water buffalo improvement programmes.