Productive and reproductive characteristics of Tarentaise cattle in the southern mediterranean regio

The Tarentaise breed in Tunisia is gaining prominence, yet comprehensive field studies on it are limited. This research aimed to delineate the breed's unique production and reproductive characteristics in Tunisia, assess non-genetic influences on milk production, and evaluate genetic progress under current management. Analyzing 345 lactations from two herds, we identified the main sources of variation in milk traits. Average milk yield, fat percent, protein percent and days in milk were 3022 kg ± 1532 kg, 3.52 ± 0.51, 3.50 ± 0.59, and 214.69 d ± 111 d, respectively. The average daily milk production was 14 kg ± 6 kg. Key findings revealed significant advantages in winter calvings and highlighted that some cows peak in performance by their sixth lactation, suggesting untapped potential. There was more than 700 kg between cows that calved in January and if the same cow calved in summer season, in favor of winter calvings. Alarmingly, both herds showed a reliance on sires with negative milk breeding values, potentially hampering genetic milk traits. Introducing tailored adjustment factors for the Tarentaise breed, our study underscores the need for optimized management to harness its full milk-producing prowess in Tunisia.