Effects of post-ovulatory food deprivation on the hormonal profiles, activity of the oviduct and ova transport in sows

Hierarchy formation in newly mixed, group housed sows and management strategies aimed at reducing its impact

“…These findings have been partially supported by studies which induced stress in sows, in the form of food deprivation, being shown to cause hormonal and metabolic disturbances during the first two days after ovulation (higher prostaglandin metabolite levels and free fatty acids and lower Oestradiol-17b and serum insulin levels in the fasted group) (Mwanza et al, 2000), although arguably the changes could be due to the deprivation of essential metabolites and nutrients versus the induced stress.…”

“…This shift may result in an improvement in sow welfare, as group housing allows for more social interactions and increased freedom for movement (Arey and Edwards, 1998;Mwanza et al, 2000;Seguin et al, 2006a;Elmore et al, 2011). The disadvantage of an increase in the use of group housing is that regrouping of sows is unavoidable (Gonyou, 2003;Razdan, 2003), resulting in an increased incidence of sow on sow aggression due to the formation of new dominance hierarchies.…”

Group housing of sows in early pregnancy: A review of success and risk factors

“…Detailed Swedish experiments showed that a 2-day period of food deprivation (i.e. no food at all) immediately after ovulation affects reproductive hormone profiles and delays transport of the early embryos (Mwanza et al, 2000). A similar period of food deprivation at Day 13/14 of pregnancy resulted in delayed embryo development (Razdan , 2004a) and lower progesterone levels and placenta size (Razdan et al, 2004b).…”

Stress-related effects on reproductive capacity of pigs

“…There were also lower cleavage rate of the embryos and fewer viable spermatozoa in the reservoir (Mburu et al, 1998). It is interesting to notice that post-ovulatory food deprivation was associated with an altered activity of the oviduct and delay of ova transport (Mwanza et al, 2000a;Razdan et al, 2001) whereas repeated administration of ACTH had no such effects (Mwanza et al, 2000c;Razdan et al, 2002). On the other hand, repeated ACTH-injections resulted in a decrease of embryonic cleavage rate and number of spermatozoa attached to zona pellucida as well as in the rapid increase in PGF 2α metabolite (Razdan et al, 2002).…”