Effects of dietary supplementation of the osmolyte betaine on growing pig performance and serological and hematological indices during thermoneutral and heat-stressed conditions

Abstract

The present study was designed to evaluate the effects of dietary betaine on pig performance and serological and hematological indices during thermoneutral and heat-stressed conditions. Individually housed pigs ( = 64; 39.0 ± 1.5 kg BW) were assigned within weight blocks and sex to 1 of 8 treatments. Treatments consisted of 2 environmental conditions (thermoneutral or heat-stressed) and 4 levels of betaine (0, 0.10, 0.15, and 0.20%). Room temperatures followed a daily pattern with a low of 14°C and a high of 21°C for the thermoneutral environment and a low of 28°C and a high of 35°C for the heat-stressed environment. Experimental diets were fed from d -7 (7 d prior to imposing temperature treatments; constant 21°C) until 28. Respiration rate and rectal temperature were measured on d 0, 1, 2, 3, 7, 14, 21, and 28, and blood samples were collected on d 3 and 28. Heat stress reduced ( ≤ 0.008) ADG (0.710 vs. 0.822 kg/d) and ADFI (1.81 vs. 2.27 kg/d) and increased G:F ( = 0.036; 0.391 vs. 0.365). Betaine tended to quadratically increase G:F ( = 0.071; 0.377, 0.391, 0.379, and 0.366 for 0, 0.10, 0.15, and 0.20% betaine, respectively), regardless of environment. Heat stress increased ( ≤ 0.001) respiration rate (48 vs. 23 breaths/30 s) and rectal temperature (39.47 vs. 38.94°C) throughout d 1 to 28. Betaine at 0.10% reduced rectal temperature in heat-stressed pigs but not in control pigs (interaction, = 0.040). Heat stress increased serum cysteine and triglycerides and reduced Ca, alkaline phosphatase, and lipase, regardless of day of sampling ( ≤ 0.048). Heat stress increased serum creatine phosphokinase (CPK) and K and reduced osmolarity, Na, urea N, methionine, homocysteine, the albumin:globulin ratio, and blood eosinophil count on d 3 but not on d 28 (interaction, ≤ 0.013). Heat stress increased serum Mg, globulin, creatinine, amylase, and γ-glutamyltranspeptidase and reduced , the urea N:creatinine ratio, alanine aminotransferase, NEFA, hemoglobin, hematocrit, and red blood cells on d 28 but not on d 3 (interaction, ≤ 0.034). Betaine increased serum osmolarity and NEFA and reduced CPK and K on d 3 but not on d 28 (interaction, ≤ 0.060) and increased serum creatinine and reduced amylase on d 28 but not on d 3 (interaction ≤ 0.057). Heat stress reduced growth, disturbed ion balance, and increased markers of muscle damage. Betaine had a minor impact on alleviating heat stress with the possible exception of early days of heat exposure. The beneficial effect of betaine was diminished by pig adaptation.

Effects of high ambient temperature on lipid metabolism in finishing pigs

“…At the end of the experiment, pigs maintained at 30°C had a higher rectal temperature than their pair-fed counterparts maintained at 22°C, which was in accordance with the results of Fernandez et al (2014) and Mendoza (2014).…”

Selenogenome and AMPK signal insight into the protective effect of dietary Se on chronic heat-stress induced hepatic metabolic disorder in growing pigs

“…In this study, it was hypothesized that HMSeBA supplementation may improve liver antioxidant capacity and mitigate liver metabolic dysfunction induced by CHS. As expected, all pigs housed in the hyperthermal environment showed a signi cantly RT and RR which are typical symptoms of CHS and have been recorded in several studies about the HS animal model [14,34]. Although no statistically signi cant difference was observed between HMSeBA and CHS groups, RR and RT in HMSeBA groups were numerically lower than CHS groups.…”

Invited review: Management strategies capable of improving the reproductive performance of heat-stressed dairy cattle

“…However, betaine also plays a role in the methionine cycle, where it acts as a substrate for the enzyme betaine homocysteine S-methyltransferase (BHMT), a back-up to methionine synthase, which converts homocysteine back to methionine (Perez-Miguelsanz et al, 2017). Betaine has already proven beneficial in heat stress for its ability to restore growth rates in heat-stressed animals (Mendoza et al, 2017;Lan and Kim, 2018). There is also evidence that betaine supplementation improves lactation, as well as restoring follicle diameter and shortening ovulation time in heat-stressed sows (Cabezón et al, 2017).…”