High environmental temperature around farrowing induced heat stress in crated sows

Abstract

The aim of the experiment was to study the impact of high ambient temperature (25°C) around farrowing on crated sows unable to perform thermoregulatory behavior. Twenty sows were housed in 2 farrowing rooms in conventional farrowing crates. In 1 room (CONTROL) temperature was kept at 20°C. In the other room (HEAT) temperature was initially kept at 20°C and gradually raised until it reached 25°C from d 112 to 115 of gestation. Then the temperature was gradually lowered to 20°C. Sows were continuously video recorded for behavior recording. Sows' respiration rates were recorded from d 3 before farrowing to d 5 after farrowing. Sows' rectal temperatures were recorded from d 1 before farrowing to d 8 after farrowing, and sows' udder surface temperatures were recorded from the day of farrowing to d 3 after farrowing. All measures were recorded daily. Sows' BW were recorded at d 108 of gestation and at weaning. Sows' back fat was recorded on farrowing day, when room temperature was set again at 20°C, and at weaning. Piglets were weighed at d 1, 14, and 21. The HEAT sows spent a higher proportion of time lying in the lateral position than CONTROL sows, both during the 16 h before farrowing and the 24 h after the start of farrowing ( < 0.05), but with no difference in the amount of time spent lying down between groups ( > 0.10). The HEAT sows had higher rectal temperature on d 1 after farrowing ( < 0.05) and had udder surface temperature 0.9°C higher than that of CONTROL sows during the recording period ( < 0.05). The HEAT sows also tended to have longer farrowing duration ( < 0.10). Respiration rate was higher in HEAT sows on d 1 before farrowing and on the day of farrowing. On d 7, 8, and 9, CONTROL sows had higher feed intake ( < 0.05), and piglets from CONTROL sows were heavier at d 21 after farrowing ( < 0.05). High ambient temperature around farrowing altered sows' postural behavior. Sows reacted to the thermal challenge with higher respiration rate around farrowing, but both their rectal and udder temperatures were elevated, indicating that they were not able to compensate for the higher ambient temperature. High ambient temperature negatively influenced sows' feed intake, with negative impact on piglets' weaning weight. High temperatures around farrowing (25°C) compromise crated sows' welfare, with a potential negative impact on offspring performance.

Effect of climate and insemination technique on reproductive performance of gilts and sows in a subtropical zone of Mexico

“…Ambient temperature and photoperiod influence weaning-to-service intervals through direct effects on the hypothalamus-hypophyseal-ovarian axis (Hurtgen andLeman 1980, Britt et al 1983). Feed intake reduction might play a role in the delayed return-to-estrus after weaning under high ambient temperature (Muns et al 2016).…”

“…Moreover, piglets born to sows that experienced heat stress during pregnancy makes them more prone to an altered metabolism resulting in animals with less skeletal muscle (Johnson et al 2015) and weaning weights (Muns et al 2016).…”

Efeito de dois sistemas de resfriamento sobre os hormônios tireoidianos e as variáveis termofisiológicas de matrizes suínas em lactação

“…A baixa ingestão alimentar provoca redução das reservas corporais, piora a condição corporal, pode desenvolver problemas reprodutivos e menor vida útil das fêmeas (Bloemhof et al, 2008). Matrizes suínas lactantes sob temperatura de 25°C reduzem a ingestão alimentar com impacto negativo na massa corporal dos leitões ao desmame (Muns et al, 2016). Alterações no comportamento e na fisiologia (Muns et al, 2016) e redução nos valores dos hormônios tireoidianos (Afsal et al, 2018) também são respostas observadas em porcas sob estresse por calor.…”

“…Matrizes suínas lactantes sob temperatura de 25°C reduzem a ingestão alimentar com impacto negativo na massa corporal dos leitões ao desmame (Muns et al, 2016). Alterações no comportamento e na fisiologia (Muns et al, 2016) e redução nos valores dos hormônios tireoidianos (Afsal et al, 2018) também são respostas observadas em porcas sob estresse por calor. A relação neutrófilo/linfócito pode ser um bom marcador quando o estresse por calor é de médio a longo prazo (Quiñonero et al, 2009).…”

Efeito de sistemas de resfriamento sobre as variáveis termofisiológicas, hormônios tireoidianos e desempenho de porcas lactantes

“…A baixa ingestão alimentar provoca redução das reservas corporais, piora a condição corporal, pode desenvolver problemas reprodutivos e menor vida útil das fêmeas (Bloemhof et al, 2008). Muns et al (2016) verificaram que temperaturas próximas a 25 °C, as matrizes suínas lactantes reduziram a ingestão alimentar, com impacto negativo na massa corporal dos leitões ao desmame.…”