Evaluating the effect of breed and calf sex on milk production and its components in cows raised in southern Iraq

Abstract

The research was done in Al Haboush Village located in the Nasiriyah District (Thi Qar Governorate) of Iraq during the time frame of October 1, 2024 to May 1, 2025. It aimed to determine how cow breed and calf sex impacted daily and total milk production as well as various chemical and physical characteristics of milk from cows raised within this area (i.e., Nasiriyah/Al Haboush Village). The study used a sample of lactating dairy cows (N = 26) from three different breeds (10 Southern, 9 Friesian, and 7 Holstein) with lactating calves of different sexes and ages. A statistically significant effect (P < .05) was observed on both daily and total milk production as a result of the breed used (Southern, Holstein, or Friesian). There was also a statistically significant difference (P < .05) in daily and total milk production between Holstein and Friesian cows on average; however, no significant difference was found between Holstein and Friesian cows when accounting for calf sex and/or age. Significant differences in several components of the milk produced between cow breeds were found (P <0.05). The Southern breed had higher percentages of total solids and fat than either the Friesian and Holstein breeds. However, cows within the Holstein and Friesian breeds had greater percentages of water (P <0.05). Although no effects of breed were determined for non-fat solids, ash content, or density of milk, Holstein cows had more protein and lactose milk than either Friesian or Southern breeds. Significant differences between the sexes of calves (P <0.05) were also present for both daily and total milk production, with daily and total milk production being greater for females as compared to males (P <0.05). Male calves had higher values for total solids, fat, protein, lactose, ash, non-fat solids, and density (P<0.05) than female calves; however, no significant differences (P<0.05) in water content were found between genders