Immune system stimulation increases the optimal dietary methionine to methionine plus cysteine ratio in growing pigs1

Abstract

Chronic subclinical levels of disease occur frequently in intensive swine production and compromise nutrient use efficiency. Feeding additional Met plus Cys (M+C) has been implicated in improving the response of the animal to immune system stimulation (ISS) because they can serve as substrates for generating compounds involved in the immune response, such as glutathione and acute phase proteins. A N-balance study was conducted to assess the optimal dietary Met to Met plus Cys ratio (M:M+C) during ISS in 20-kg pigs. Thirty-six pigs were fed 800 g/d of 1 of 5 M+C-limiting diets, containing graded levels of M:M+C (0.42, 0.47, 0.52, 0.57, and 0.62) and supplying 2.5 g/d of M+C. After adaptation, N balances were determined sequentially during a 5-d prechallenge period and 2 ISS periods of 3 and 4 d, respectively. To induce ISS, pigs were injected intramuscularly with repeated and increasing doses of Escherichia coli lipopolysaccharide. Eye temperature and blood profile confirmed effective ISS. During ISS period 1, ISS reduced the mean N balance more severely than ISS period 2 (8.7 ± 0.3 vs. 9.6 ± 0.4 g/d; P < 0.001) and was less than the prechallenge period (10.0 ± 0.2 g/d; P < 0.001). An interactive effect of ISS and diet on N balance was observed (P < 0.001). Based on quadratic-plateau regression analysis, the optimal dietary M:M+C was 0.57 ± 0.03 and 0.59 ± 0.02 for the prechallenge period and ISS period 2, respectively. The optimal dietary M:M+C for ISS period 1 was found to be greater than 0.62, indicating that the optimal M:M+C is greater during ISS. It is suggested that this is the result of preferential use of Met during ISS. In conclusion, ISS results in an increase in the optimal dietary M:M+C in growing pigs.

Determination of the optimum standardised ileal digestible sulphur amino acids to lysine ratio in weaned pigs challenged with enterotoxigenic Escherichia coli

“…However, the present study found a decreasing trend of plasma albumin with increasing SID SAA:Lys immediately after infection. These findings are in contradiction with work by Litvak et al (2013) who found that higher Met:SAA increased plasma albumin. Albumin catabolism produces AA and it is thought that the decrease albumin in animals suffering from infection is due to increased breakdown rather than decreased synthesis (Reeds and Jahoor, 2001).…”

“…Nevertheless, literature on plasma albumin is contrasting where some authors (Heegaard et al, 2011;Rakhshandeh and de Lange, 2012) showed no response of immune stimulation (using an LPS injection) on plasma albumin, however, Litvak et al (2013) found that immune stimulation caused by LPS injection decreased plasma albumin. Rothschild et al (1979) found that in cases of myxedema there was evidence of tissue trapping of albumin.…”

Effect of supplemental dietary leucine and immune system stimulation on whole-body nitrogen utilization in starter pigs

“…injection of LPS was selected as the non-infectious disease model. Based on previous studies, this model shows a predictable response immediately following the initial LPS injection, but pigs can develop tolerance to LPS such that they no longer exhibit a clinical response to subsequent LPS injections (Rakhshandeh and de Lange, 2012;Litvak et al, 2013). This is consistent with the pattern of N retention observed in the preliminary study (Fig.…”

Biomarkers of inflammation, metabolism, and oxidative stress in blood, liver, and milk reveal a better immunometabolic status in peripartal cows supplemented with Smartamine M or MetaSmart

“…Because Met is an upstream precursor of Cys through the transsulfuration pathway, it has been suggested that Met plays an important role during the APR (Lu, 2009). In fact, Litvak et al (2013) observed a significant decrease in albumin concentration (38.3 vs 33.7 g/L) in growing pigs fed a Met-deficient diet before and after an APR was induced via intramuscular injection of Escherichia coli LPS. In contrast, albumin remained unchanged in pigs fed adequate amounts of Met before and after APR induction.…”