Nilufer Sabuncuoglu

Effect of some parental and environmental factors on some reproductive traits of Japanese quails

Abstract The present study was undertaken to determine the influence of parental and environmental factors (body weight, laying period, egg weight and light) on some reproductive characteristics of the Japanese quail. Data pertaining to 2413 eggs obtained from 40 male and 40 female Japanese quails were studied using a logistic regression model. Hatchability was determined to decrease with parent body weights falling below the population mean. Fertility and hatchability were determined to decrease with the ageing of breeder pairs. The relationship between egg weight and fertility was demonstrated to be insignificant, yet the best hatchability was determined in eggs weighing 11-12 grams (P<0.01). Both fertility and hatchability were determined to decrease with increasing light intensity (P<0.01).

Relationship between udder and teat conformation and milk yield performance in dairy cows pre- and post-milking

The objectives of this study were to determine the relationship between udder floor area (UFA) and milk production traits in dairy cows, pre- and post-milking, as well as to examine the usefulness of a simple method of measuring UFA. The absolute reduction (AR, cm2) and relative reduction (RR, %) in UFA post-milking relative to pre-milking was calculated. Absolute reduction was influenced by breed and lactation stage, but not by parity of the cows (P < 0.05). There was no effect of breed and stage of lactation on the RR of UFA. Moderate correlations were observed between absolute reduction of UFA and daily milk yield (r2 = 0.422), lactation milk yield (r2 = 0.426), and absolute fat yield (r2 = 0.515) (P < 0.01 and P < 0.05). Moderate and weak correlations were found between RR of UFA and daily milk yield (r2 = 0.335) (P < 0.01), AR of the udder area and the 305-d lactation milk yield (r2 = 0.326) (P < 0.10). It was concluded that measuring UFA using the method described may be useful for the selection of ...