دورية أكاديمية

Feed intake–dependent and –independent effects of heat stress on lactation and mammary gland development.

التفاصيل البيبلوغرافية
العنوان: Feed intake–dependent and –independent effects of heat stress on lactation and mammary gland development.
المؤلفون: Xiao, Yao1,2 (AUTHOR), Kronenfeld, Jason M.1 (AUTHOR), Renquist, Benjamin J.1 (AUTHOR) bjrenquist@email.arizona.edu
المصدر: Journal of Dairy Science. Dec2020, Vol. 103 Issue 12, p12003-12014. 12p.
مصطلحات موضوعية: *MAMMARY glands, *PHYSIOLOGICAL effects of heat, *LACTATION, *HEAT, *MILK yield, *ARTIFICIAL selection of animals, *ANIMAL species
مستخلص: With a growing population, a reliable food supply is increasingly important. Heat stress reduces livestock meat and milk production. Genetic selection of high-producing animals increases endogenous heat production, while climate change increases exogenous heat exposure. Both sources of heat exacerbate the risk of heat-induced depression of production. Rodents are valuable models to understand mechanisms conserved across species. Heat exposure suppresses feed intake across homeothermic species including rodents and production animal species. We assessed the response to early-mid lactation or late-gestation heat exposure on milk production and mammary gland development/function, respectively. Using pair-fed controls we experimentally isolated the feed intake–dependent and –independent effects of heat stress on mammary function and mass. Heat exposure (35°C, relative humidity 50%) decreased daily feed intake. When heat exposure occurred during lactation, hypophagia accounted for approximately 50% of the heat stress–induced hypogalactia. Heat exposure during middle to late gestation suppressed feed intake, which was fully responsible for the lowered mammary gland weight of dams at parturition. However, the impaired mammary gland function in heat-exposed dams measured by metabolic rate and lactogenesis could not be explained by depressed feed consumption. In conclusion, mice recapitulate the depressed milk production and mammary gland development observed in dairy species while providing insight regarding the role of feed intake. This opens the potential to apply genetic, experimental, and pharmacological models unique to mice to identify the mechanism by which heat is limiting animal production. [ABSTRACT FROM AUTHOR]
قاعدة البيانات: Academic Search Index
الوصف
تدمد:00220302
DOI:10.3168/jds.2020-18675