Effects of sex, morphological characteristics and haemoglobin type on the growth traits of red sokoto goats in semi-arid region of Nigeria

Abstract

The experiment was conducted to determine effects of sex, morphological characteristics and haemoglobin type on the growth traits of Red Sokoto goat. A total of 321 Red Sokoto goats were used for the study. The population of Red Sokoto goats was studied in Hardy-Weinberg equilibrium. The frequencies of observed morphological characteristics such as coat type, hair type, tail shape, tassels and sex were recorded. The body mensuration characteristics of the goats were identified and their effects on the performance were also assessed. Four haemoglobin types were discovered, namely; HbAA, HbAB, HbBB and HbAC. Only two (2) animals sampled had the rare pre-adult haemoglobin type (HbAC). The distribution of all the parameters were determined using Chi-square analysis and the Haemoglobin types were expressed as homozygous (HbAA and HbBB) and heterozygous (HbAB and HbAC). Data collected were subjected to analysis of variance (ANOVA) using the General Linear Model (GLM) procedure of SAS. The Red Sokoto goats within 8 months of age had the highest frequencies (24.61 %) while the least (3.12 %) was obtained in those that are within 48 months. The highest coat type, hair type and tail shape were found in Brown (B), Short-smooth (SS) and Curled up (CU) respectively. The Red Sokoto goats without tassels (308) were more than those with tassel (13). Sex significantly (P<0.05; P<0.01) affected the body mensuration traits except body length with the does having superior performance compared to the bucks. Tassel had no significant (P>0.05) effect on all body mensuration traits. Hair type significantly (P<0.05; P<0.01) influenced body mensuration traits of Red Sokoto goats. The long-curly and short-smooth were superior to short-rough hair typed goats in all the body mensuration traits. Tail shape had no significant (P>0.05) effect on body mensuration traits in Red Sokoto goats except on body length (P<0.01). Goats with curled up tails were superior to those with curled down and straight tails. Hb type significantly (P<0.05; P<0.01) influenced the body mensuration characteristics except body depth. The HbBB typed goats were superior in performance compared to HbAA typed goats; while the HbAB typed goats were the intermediates. The HbAC typed goats were the least in performance compared to HbBB, HbAA and HbAB variants in Red Sokoto goats. In essence, the haemoglobin genotype HbAB in Red Sokoto goats seems to be favoured by natural selection with preponderance for the HbAA allele. Goats with the SS and LC hair type and BWS coat type recorded greater production performance in terms of the mensuration traits. In conclusion, the significant effect of Hb type and all other physical indicators for production show that with careful genetic studies and proper documentation of records, variation in our goat herd could be drastically improved within a short time.

Keywords: Goat, Red Sokoto, Semi-arid, Haemoglobin types, Morphological Characteristics