author(s)
Nandani Kumari, Ravindra Kumar, Sushil Prasad, Swapanil, Bhushan Kumar Singh and Lal Babu Singh

abstract
The population of the crossbred pigs have increased from 14% in 1992 to 23.86% in 2012. Being one of the cheapest meat source in India, swine production is a choicest profession now at Pan-India level. Increase in population coupled with limited resources have augmented the need towards crossbreeding programmes in India to reduce the gap between demand and supply of protein source. Jharsuk (T&D) breed is well known for its good performance and adaptability due to 50% inheritance each of Tamworth and Desi respectively. Current study deals with (i)the effect of genetic groups on different growth traits like body weight at 0, 7, 14, 28, 42, 56 days and body weight gain between different ages and (iii) effect of Genetic groups, TLR 6 gene polymorphism and piglet titre on litter size at birth and litter size at weaning. Significant effect of genetic groups on Body weight at 42 days, 56 days, body weight gain between 42-56 days was observed. For TLR 6 gene polymorphism a total of nine sets of forward and reverse primers were taken for amplification of DNA samples for TLR6 gene loci. All eight primers produced amplified product except the fourth primer (TLR6-4). PCR products were subjected to polyacrylamide gel electrophoresis for the detection of single strand conformational polymorphism (SSCP). Different numbers of haplotypes, obtained with the eight primers were analyzed with the Spab software to see the association of these variants with important economic traits under study. Genetic group (Breeds) had significant effect on litter size at birth while, piglet titre (HA titre) had non-significant effect on litter size at birth and weaning. In many cases Jharsuk Variety (T&D) was found to be superior to or at par with its exotic F₀ breed i.e. the Tamworth breed. Current findings suggest the usefulness of Jharsuk and its superiority over Tamworth and Desi as a very profitable breed in Jharkhand and it could be further continued with increased sample size for each of the three experimental breeds taken. The research is important more so because it deals with threshold characters, which is very complex subject in itself and need to be studied more to know detail on its inheritance.