Crossbreeding of large white and Nsukka local pigs: Genotype and age are related changes in haematological parameters

Abstract

5-Blood samples from 80 pigs of 4 genotypes - the Nsukka local (Lo), the exotic Large White (LW), the one-way F₁ (LW x Lo) and the F₂ crosses belonging to 5 age groups, were analyzed, to determine the mean values of the haematological parameters in the genotypes and different age groups and to check if and how the values are altered by crossbreeding. The local pigs had significantly (P<0.05) higher haemoglobin (Hb, 11.64 g/100 ml), packed cell volume (PCV, 47.00%), red blood cells (RBC, 7.06 x 10⁶/mm³), white blood cells (WBC, 16.50 x 10³/mm3) and lymphocytes (61.45%) than the Large White (LW - 10.77g/100ml, 41.55%, 6.26 x 10⁶/mm³, 10.65 x l10³/mm³ and 50.59%, respectively), with Fl and F2 crosses intermediate in values. The mean corpscular heamoglobin (MCH), the mean corpuscular heamoglobin concentration (MCHC), monocytes, neutrophils and corpuscular were highest in the LW (17.26 u2g, 25.92%, 6.60%, 39.05%, and 5.20%, respectively) and the lowest in the Lo (16.5 u2g, 24.59%, 4.8%, 30.90% and 2.45%, respectively), with Fl and F2 intermediate. The LW, Lo and Fl were similar in mean corpuscular volume (MCV). There were significant (P<0.05) increases in Hb, PCV, RBC, WBC, lymphocytes and eosinophils with age. However, significant genotype x age interactions were found for RBC, MCH, WBC, lymphocytes, monicytes and eosinophils which limit the inferences made on the main effects. Heterosis estimates based on the one-way Fl were zero, negative or low for most of the parameters. It was concluded that the blood parameters studied are heritable and that additive gene action was important in their inheritance, suggesting that they should respond to selective breeding.

Key words: Crossbreeding, genotype, age, blood parameters, pigs