Differences in Weight, Hierarchy, and Incidence of Lameness between Two Groups of Adult Pigs Derived from Assisted Reproductive Technologies

Abstract

The in vitro production (IVP) and subsequent transfer of embryos (ET) to recipient mothers is not yet an established reproductive technology in the pig industry, as it is in cattle. However, that the trade of IVP-cryopreserved pig embryos is expected to start in the next decades. Society and governments are increasingly aware of the repercussions that IVP could have for animal health, welfare, behavior, or food safety, but proven scientific information for this type of animal does not exist, since no colonies of pigs have been created to this end. We created a small one and studied the differences between 16 IVP-derived pigs and 14 pigs derived from artificial insemination (AI), at 3.5 years of age, conceived from the same boar, and housed and fed under the same conditions since they were born. Incidence of lameness, position in the herd hierarchy, weight, adenosine deaminase activity, and hematological and biochemical analytes were compared between the two groups of animals. The results showed that the IVP animals weighed more, occupied higher positions in the herd hierarchy, and had a lower incidence of lameness. Although genetic differences from the maternal line could explain some of these results, it is also possible that the IVP animals developed better adaptative abilities, but more studies with a higher number of animals are necessary to reach consistent conclusions.

Effect on Feeding Behaviour and Growing of Being a Dominant or Subordinate Growing Pig and its Relationship with the Faecal Microbiota

“…The connection between hierarchy and weight has also been recently studied through the observation of queue formation at feeders. In non-preferred feeder access locations, the presence of light pigs led researchers to infer that these were submissive animals, while those in better positions in the queue would be dominant [25] . On the other hand, the observed patterns suggest that our proposed dominance test would allow us to identify those animals that would outperform their submissive pen peers in terms of growth, or conversely, those that would underperform in similar circumstances compared to their dominant peers.…”

Feline Wharton’s jelly-derived mesenchymal stem cells as a feeder layer for oocytes maturation and embryos culture in vitro

“…After years of investigations, the basic nutritional requirements for oocytes and embryos have been established, guaranteeing successful in vitro development in horses ( 2 ), cattle ( 3 ), pigs ( 4 ), mice and humans ( 5 ). However, ART in a feline species is still not as efficient as in other animals.…”