Are the two polymorphic sites of anti-Marek’s disease in White Leghorn chickens also suitable for Partridge Shank chickens?

Abstract

<b>Background: </b>The selection of Marek’s disease (MD)-resistant breeds in Partridge Shank chicken, a popular local chicken breed in Henan Province of China, has practical value. We hypothesized that the two polymorphic sites (<i>rs14527240</i> located in <i>SMOC1</i> and <i>GGaluGA156129</i> located in PTPN3) related to MD resistance in White Leghorn chickens are also applicable to Partridge Shank chickens. <b>Methods: </b>In this experiment, we screened 10 live hens and 2 live roosters with the double GG genotype by genotyping the two sites from 6500 Partridge Shank chickens. Nineteen one-day-old chicks with the double GG genotype were obtained by artificial insemination. Seventy-two one-day-old chickens (19 from the population expansion test and 53 randomly selected from chicken farms) were injected with 2000 plaque-forming units of the Md5 virus strain. After 100 days of infection, all chickens were examined by pathological anatomical examination, histological sectioning, genotyping, and a quantitative polymerase chain reaction of <i>SMOC1</i> and <i>PTPN3</i>. <b>Results:</b> There was only one site (<i>rs14527240</i> located in <i>SMOC1</i>) associated with MD in Partridge Shank chickens (<i>p</i> < 0.05), but the GG genotype of <i>SMOC1</i> in Partridge Shank chickens indicated susceptibility to MD. <i>SMOC1</i> expression in MD-susceptible chickens was also significantly higher than that in MDresistant chickens (<i>p</i> < 0.05). <b>Conclusion: </b>Therefore, the MD resistance sites selected from White Leghorn chickens were not completely suitable for Partridge Shank chickens, but they can be used as a reference. This study indicated that <i>SMOC1</i> plays an important role in screening for MD resistance in poultry.