Reproduction traits of heterozygous myostatin knockout sows crossbred with homozygous myostatin knockout boars

• Published in: Reproduction in domestic animals Vol. 56; no. 1; pp. 26 - 33
• Main Authors: Han, Sheng‐zhong, Li, Zhou‐Yan, Paek, Hyo‐Jin, Choe, Hak‐Myong, Yin, Xi‐Jun, Quan, Biao‐Hu
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 01.01.2021
• Subjects: Breeding; Dyspnea; Hogs; Meat; MSTN gene; Mutants; Mutation; Myostatin; pathological features; Phenotypes; piglet; Reproduction; reproductive ability; Respiration; Semen; sows; pathological features; reproductive ability; piglet; sows; myostatin
• ISSN: 0936-6768; 1439-0531
• DOI: 10.1111/rda.13845

Few studies exist on homozygous myostatin gene mutant (MSTN−/−) pigs, especially on their reproductive ability. We have previously shown that semen quality of homozygous MSTN−/− boars is comparable to that of wild type (WT). However, no data exist on the reproductive ability of heterozygous MSTN gene mutant (MSTN+/−) sows. The present study highlights showed that the heterozygous MSTN+/− sows have delayed pubertal age than WT sows (255.80 ± 6.79 versus 191.10 ± 3.42, respectively). The number of services per pregnancy of heterozygous MSTN+/− sows is significantly higher than that of WT sows (3.33 ± 0.43 versus 1.60 ± 0.25, respectively). Moreover, although heterozygous MSTN+/− sows have natural reproduction ability, their litter size was significantly lower than that of WT sows (7.75 ± 0.44 versus 14.25 ± 0.60, respectively). Offsprings generated from heterozygous MSTN+/− sow and homozygous MSTN−/− boar were genotyped with the PCR and sequencing method to detect myostatin mutation and to identify whether the piglets are homozygous MSTN−/− or heterozygous MSTN+/−. The proportion of homozygous MSTN−/− piglets was significantly lower than that of heterozygous MSTN+/− piglets (2.50 ± 0.35 versus 5.25 ± 0.60, respectively). Furthermore, none of the sows presented dystocia, and the phenotype of heterozygous MSTN+/− piglets was normal. However, 10% homozygous MSTN−/− piglets died of dyspnoea within 2 hr after birth, 60% of homozygous MSTN−/− piglets showed large tongues, and 50% had umbilical hernias. In summary, this study for the first time reports the reproduction traits of heterozygous MSTN+/− sows crossbred with homozygous MSTN−/− boars. This study will pave the way in a new direction for the breeding and development of super lean meat varieties in the future.