Comparison of phenotypic and heterotic effects affecting milk yield, composition and udder morphometry of Hair and F1, F2 and G1 generation cross-breeds of Alpine × Hair and Saanen × Hair dairy goats in a semi-intensive system.

This study was conducted to compare milk yield, milk components and udder traits of Hair goat, F1, F2 and G1 generation cross-breeds of Alpine × Hair and Saanen × Hair goats under a semi-intensive system. The effects of genotype, parity, flock and year on milk production, physical and chemical compositions were almost all significant (between p < 0.05 and p < 0.001). The F1, F2 and G1 generations produced 24 and 44% higher (p < 0.001) lactation milk yield (LMY), 12 and 35% (p < 0.001) fat yield and 19 and 35% (p < 0.001) protein yield than Hair goat. Positive heterosis was found in milk production and contents both Alpine × Hair F1 (AHF1) and Saanen × Hair F1 (SHF1) generations. The heterotic effect of the LMY was significant in the SHF1 generation (p < 0.05), but not in the AHF1 generation. The highest correlation was found between LMY and udder circumference and then udder volume (p < 0.001; r = from 0.34 to 0.75). The coefficient of determination of the obtained equation for the estimation of the LMY in the Hair and cross-bred goats ranged from 0.48 to 0.71. These results showed that as the level of cross-breeding increased in this semi-intensive system, better quality dairy products can be obtained from goats, and udder measurements can be a helpful tool in estimating milk yield, thus reducing the pressure on the ecosystem. Thus, it was concluded that with better modelling of environmental variations, milk production characteristics of local goats can be increased much faster by cross-breeding, especially at the F1 and G1 generation cross-breed levels.

Determination of factors affecting milk yield, composition and udder morphometry of Hair and cross-bred dairy goats in a semi-intensive system.

In this Research Communication we report milk yield, milk composition and udder morphometry of Hair, Alpine × Hair F1 (AHF1), and Saanen × Hair F1 (SHF1) cross-bred goat genotypes managed in a semi-intensive system. The SHF1 genotype had significantly higher lactation milk yield, fat yield, protein yield, and electrical conductivity than other genotypes, whilst AHF1 was intermediate. The milk fat, protein, lactose, solids-non-fat and total solids contents as well as pH and density of the Hair goat milk were significantly higher than the corresponding values of the cross-bred genotypes. The highest correlation amongst udder characteristics and production was between lactation milk yield and udder volume (P < 0.01; r = from 0.63 to 0.77). The results of this study suggest that crossbreeding can have a positive effect on the milk production characteristics of local goats, thereby reducing the pressure on the ecosystem, and suggest that udder measurements, especially volume, can be a helpful tool for estimating milk yield.

Some descriptive characteristics of a new goat breed called Honamli in Turkey.

This study has been carried out in the Western Mediterranean Region of Turkey on seven different Honamli goat flocks. The aim of this study was to determine the growth characters, survival rate (till weaning, 105th day), some reproductive characteristics and marketable milk yield. The data were collected from 516 does and 210 kids (125 buckling and 85 doelings). The results indicate that the numbers of multiple birth and litter size were 32.8 % and 1.35 respectively. Survival rates of kids at the 30th, 90th, and 105th days were 98.5, 97.2, and 97.2 %, respectively. The average birth weight for the buckling and doelings was 4.1 and 3.7 kg, respectively. The average weaning weights for buckling and doelings were 26.9 and 23.4 kg, respectively. The effects of dams' age, on sex and birth type on the growth of Honamli kids were statistically significant (p < 0.05, p < 0.01, and p < 0.001). While the diameters of erythrocytes of Honamli goats are smaller, the density of hemoglobin in the erythrocytes is more than Asian, Indian, and American caprine breeds. The average lactation length and marketable milk yield was assessed to be at 210.3 days and was 89 L, respectively. The growth characteristics of Honamli kids at weaning age were assessed to be higher than most of the other goat breeds in Turkey. The results further indicated that there is a significant variation in the production traits among the different Honamli goat flocks. Production traits of Honamli goats at different breeding conditions should further be investigated to come to a definite conclusion.