Intrauterine Programming of Physiological Systems: Causes and Consequences

Producers have the possibility to combat human-induced dryland salinity by planting salt-tolerant plants such as saltbush. Saltbush has the potential to be used as a source of food for livestock at a time and place where pasture is not viable. However, saltbush contains high concentrations of sodium chloride salt and some other anti-nutritional factors that have the potential to affect feed and water intake and, directly or indirectly, the reproductive capacity of sheep. High-salt diet during gestation induces a small modification of the activity of the renin-angiotensin system (RAS) that has an important role in the maintenance of the salt-water balance in non-pregnant and pregnant sheep. In contrast, the main effect of salt ingestion during pregnancy is observed on the biology of the offspring, with changes in the response of the RAS to salt ingestion and altered thirst threshold in response to an oral salt ingestion. These changes, observed later in life, are the result of fetal programming following the ingestion of salt by the mother. It seems that the exposure to salt during pregnancy could provide an advantage to the offspring because of this adaptive response. The response may be particularly useful, for example, when grazing herbivores are fed halophytic forages adapted to saline soils.

Section: Fetal Programming During Intra-utero Exposure To Saltmentioning

confidence: 99%

Section: Fetal Programming During Intra-utero Exposure To Saltmentioning

confidence: 99%

Salt intake and reproductive function in sheep

Digby

Chadwick

Blache

2011

“…Long-term effects IUGR and low BWT of human infants have received special attention because of their long-term effects on adult onset of various diseases (Gluckman and Pinal, 2003;Schwartz and Morrison, 2005;Bloomfield et al, 2006b;De Boo and Harding, 2006;Fowden et al, 2006a;Murphy et al, 2006). Similarly, low BWT was found to have long-term effects in sheep on glucose tolerance and blood pressure at 5 months but not at 30 months of age, and long-term effects at 30 months but not at 5 months of age on insulin tolerance and circulating levels of IGF1 (Oliver et al, 2002).…”

Section: Maternal Overnutritionmentioning

confidence: 99%

Litter-size-dependent intrauterine growth restriction in sheep

Gootwine

Spencer

Bazer

2007

Regulation of foetal development in sheep depends on interactions between the intrinsic capacity of the foetus for growth and the maternal environment. Lambs born in multi-foetus litters have relatively small placentae with fewer cotelydons, and lower birth weights. Litter-size-dependent intrauterine growth restriction (IUGR) is evident at mid gestation when metabolic needs of the conceptus are moderate, and overnutrition of ewes with multiple foetuses does not promote growth of their foetuses to the size of singletons. Those observations suggest that placental and conceptus growth in multi-foetus pregnancies is reprogrammed at mid gestation by an as yet undefined mechanism to attenuate foetal growth. This may protect the foetus from severe nutritional insult during late gestation, when its daily growth rate is at a maximum. In that way, lambs born in large litters with relatively lower birth weights may not experience the long-term physiological insults that can be observed in small lambs born to undernourished ewes.

“…In species with multiple foetuses like pigs, maternal stress is suspected to reduce the number of youngs born alive, suggesting an increased foetal mortality (von Borell et al, 2007). In addition, maternal stress during gestation can have detrimental effects on growth (Fowden et al, 2006), neuroendocrine (Weinstock, 1997) and immune (Merlot et al, 2008) functions in the offspring after birth. The deleterious effects of stress on pregnancy and foetal development seem to be related to maternal immune changes (Arck, 2001;Joachim et al, 2003;Coussons-Read et al, 2007) and to maternal neuroendocrine activity, especially to glucocorticoid secretions (Barbazanges et al, 1996).…”

Section: Introductionmentioning

confidence: 99%

Behavioural, endocrine and immune responses to repeated social stress in pregnant gilts

Couret

Otten

Puppe

et al. 2009

Pregnant sows are exposed to various stressors in intensive pig husbandry that may have negative consequences on their health, reproductive performances and welfare. Social stress is one of these challenges, because gestating sows have to be housed in groups according to EU guidelines (2001/88/CE). The purpose of this study was to determine the consequences of repeated social stress in pregnant female pigs on their behavioural, endocrine and immunological responses and on pregnancy outcome. Pregnant gilts were submitted to a repeated social stress procedure induced by housing unfamiliar gilts in pairs changed twice a week between days 77 and 105 of gestation (S group, n 5 18). Control gilts were housed in stable pairs during the same period (C group, n 5 18). Agonistic behaviour was observed during the first 3 h after each grouping. Skin lesions were numbered 2 h after each grouping. Salivary cortisol was measured before and repeatedly during the 4 weeks of grouping. Gilts were immunized against keyhole limpet haemocyanin (KLH) on days 81 and 95 of gestation. Immunoglobulins G against KLH, proliferative responses to concanavalin A, lipopolysaccharide, pokeweed mitogen and KLH and peripheral blood leukocyte numbers were evaluated 1 week before the first grouping and 3 days after the last one. Agonistic interactions and skin lesions were observed in S gilts at each grouping, although there was a decline between the first and the last grouping ( P , 0.05). The repeated social stress induced a sustained endocrine response as shown by elevated salivary cortisol levels from 1 to 48 h after grouping in S gilts compared to C gilts. The cellular as well as the humoral immunity and the leukocyte numbers were not influenced by social stress. Gestation length tended to be shorter in S gilts ( P 5 0.09), but litter size, piglet weight or mortality at birth were not affected. Variability of the response of S gilts to groupings was partly explained by their average success value determined according to the outcome (defeat or win) of all the groupings. In conclusion, our study demonstrates that the application of repeated social stress to pregnant gilts during the last third of their gestation repeatedly activates their hypothalamo-pituitary-adrenal axis but does not impair their immune function and pregnancy outcome.