Semen quality factor as an indicator of fertilizing ability for geese.

The semen quality factor (SQF) takes into account 3 semen parameters as a means of predicting semen fertilizing ability: semen volume, semen concentration, and the percentage of live and morphologically normal spermatozoa. The objective of this study was to test the suitability of the SQF as an indicator of fertility for geese. Twenty-one ganders were divided into 3 groups based on their individual SQF values, and semen was pooled within each group. A fourth semen group was generated by diluting semen from the highest SQF group with 2 vol of diluent. Pooled semen was inseminated into 30 geese per treatment. Relationships between SQF and fertility were evaluated. Testosterone and estradiol levels in seminal plasma were determined by competitive immunoassays. The SQF values of the 4 diluted semen groups were 19.3, 11.3, 9.5, and 13.1, and the corresponding fertility values, determined by candling, were 83.9, 65.6, 56.8, and 74.3%, respectively. The correlation coefficient between SQF and fertility was 0.985 (P < 0.01), indicating that the SQF can be used as a good indicator of fertility for geese. The SQF values correlated well with the ratio of testosterone to estradiol in seminal plasma (r = 0.48, P < 0.05), which could also be a diagnostic tool for evaluating the reproductive potential of individual ganders.