The Martina Franca (MF) donkey breed (Equus asinus) primarily inhabits the rural areas surrounding the homonymous municipality, as well as neighboring municipalities in the provinces of Bari and Brindisi, all located in the Apulia region of Italy. The objective of this study was to assess the current phenotype through the evaluation of 27 morphologic measurements. The study was conducted on 73 female and 18 male breeding animals from eight different herds located in central and southern Italy. Statistical analysis was performed in order to demonstrate statistical differences between males and females, as well as sexual dimorphism and uniformity of all measurements in both genders. The results demonstrated that the mean of three parameters used for the evaluation of an MF donkey (height at withers, circumference of thorax, and shin circumference) are highly representative of the population, with minimal dispersion $\widehat{C_v}$ = 0.05–0.06 up to a maximum of 10%, as evidenced by relatively low standard deviations across observed measurements in both genders. Regarding sexual dimorphism, a statistically significant difference was found between males and females. This dimorphism is linked to reproductive activity and is useful during gestation. Overall, our findings suggest that the MF donkey phenotype has been largely preserved over time with high uniformity in males, slight inhomogeneity in the female population, and less variability in both genders.

The Abruzzo (AB) donkey is a mountain-adapted Italian population listed as a genetic resource at risk of extinction (census ≈ 600 animals; no studbook). We aimed to provide the first comprehensive morphometric description of the breed and to compare it with the Martina Franca (MF) donkey, its main progenitor. Sixty-nine adult donkeys (56 females, 13 males) from six farms were measured in 2024. Twenty-three linear traits plus body weight and body condition score were recorded three times by a single operator. Descriptive statistics, Welch’s t-test or Mann–Whitney U test with Benjamini–Hochberg correction, PCA and LDA with leave-one-out cross-validation were performed in R; comparison with MF was based on published summary statistics. Coefficients of variation for the three studbook-admission parameters were ≤0.10 in both sexes. Sixteen of 26 traits showed significant sex dimorphism, with the largest effect sizes for rump height, medial canthal distance and wither height. LDA correctly classified 94% of animals by sex. AB females were significantly smaller than MF in 22 of 23 shared traits but had a wider thorax (p = 0.012). The sexual dimorphism observed in the Abruzzo donkey is male-biased and predominantly size-based, with a minor and well-localised shape component in the head region. Males are significantly larger than females for all axial measurements (wither height A: +6.5 cm, +5.3%; rump height B: +6.4 cm, +5.0%; trunk length D: +12.1 cm, +9.5%), for thoracic circumference (M: +7.1 cm, +5.0%), for body weight (+49.9 kg, +20.6%) and for the main head traits (CM: +4.3 cm, +20.0%; G: +3.6 cm, +12.5%; H: +1.3 cm, +11.1%; E: +2.0 cm, +3.8%); no trait shows a significant female bias after BH-FDR correction. The AB donkey shows a uniform mesomorphic phenotype, smaller and stockier than MF, supporting the establishment of an official studbook.