Breeding soundness examination (BSE): a decision-making tool that requires a particular guideline for male goats.

Breeding soundness examination (BSE) is a common evaluation to predict the reproductive ability of male livestock. The generated guideline for BSE is specified for each animal species to enhance the performance of BSE. However, there is no particular BSE guideline for bucks yet; then, the BSE guidelines for ram and bull are commonly used for bucks. This investigation was conducted to determine the main BSE characteristics and the appropriate age range for assessment in Boer goats. For this purpose, semen was collected using electro-ejaculation, and seminogram variables (semen-BSE traits) were evaluated using conventional methods. The association between common testicular biometric variables (TBVs) and semen-BSE traits were assessed using Pearson's correlation coefficients and multiple linear regression. Logistic regression was used to test the validity of TBVs for the BSE of Boer goats. In this study, a strange appearance of the head of sperm, known as "rod-in-head" (RIH), was observed. The results showed that the appropriate age range for performing BSE in bucks is 12-30 months. Moreover, scrotal length in the range of 10-15.9 cm was the eligible TBV to be used as a predictor for semen-BSE traits. It was suggested that developing a BSE guideline for bucks is necessary for unbiased selection in performing BSE.

Novel SNPs in the SPAG11 gene and association with testicular biometric variables in Boer goats and application of the levelled-container technique.

Testicular volume (TV) is one of the most important traits used in evaluation of the reproductive capacity of male animals. The levelled-container used in the present study was found to be reliable instrument to measure TV, based on a water displacement method. Sperm-associated antigen 11 (SPAG11) is an important gene that affects male reproductive performance. An objective of the present study, therefore, was to determine if single nucleotide polymorphisms (SNPs) in a fragment of the SPAG11 gene could be used to determine associations with values of testicular biometric variables in Boer goats. Primers were designed to amplify the full length of the first two exons of SPAG11. The targeted fragment was generated using a molecular cloning technique. As the result, four SNPs, [g.1256A > G(ss19199134542), g.1270C > T(ss19199134541), g.1325A > G(ss19199134540) and g.1327 G > A (ss19199134543)], were detected using a single-base extension (SBE) method. Two of these SNPs were synonymous (ss19199134540 and ss19199134542). The other two SNPs were nonsynonymous, thus, there were changes in amino acid in the resulting protein: threonine to isoleucine (for ss19199134541) and arginine to glutamine (for ss19199134543). The SNP ss19199134543 was the only locus detected that was associated with TV (P = 0.002). None of the testes dimensions nor TW were associated with detected SPAG11 gene SNPs. Most likely, the ss19199134543 locus affects tissue structures adjacent to the testes, causing the change in TV. In conclusion, among the studied testicular biometric variables, TV had the greatest potential for preselecting of bucks with desirable semen quality. The use of the levelled-container as a TV measurement approach was an accurate and reliable method.