Response to an Escherichia coli K88 oral challenge and productivity of weanling pigs receiving a dietary nucleotides supplement

Abstract

BackgroundDietary nucleotides, considered as antibiotics alternative, were shown to have positive effects on intestinal hyperaemia, systemic immunity, small-intestinal growth, and hepatic composition in pigs. However, there is no previous research on nucleotide supplementation in weanling pigs under an oral challenged E. coli K88. Therefore, 2 experiments were conducted to investigate the effects of dietary nucleotides on weanling pig growth performance, nutrient digestibility, fecal score, and blood profile after being orally challenged with E. coli K88.MethodsIn Exp. 1, a total of 140 weanling pigs [8.33 ± 0.33 kg of body weight (BW), 28-d old] were used in this 42-d feeding trial. Pigs were distributed into 1 of 4 treatments, 5 pigs/pen (3 barrows and 2 gilts) and 7 pens/treatment. Treatments were a control basal diet (CON) or the CON supplemented with 150 (R150), 220 (R220), or 275 (R275) mg/kg to give the three treatment diets. In Exp. 2, 28 weanling pigs (BW = 8.40 ± 0.22 kg, 28-d old) were distributed into 1 of 4 treatments to give 1 pig/pen and 7 pens/treatment in a 42-d feeding and challenge trial. Dietary treatments were the same as in Exp. 1. On d 14, all those pigs (BW = 13.3 ± 0.15 kg, 42-d old) were orally dosed with 1.5 mL suspension containing 1010 cfu/mL of E. coli K88. Twenty four hours after challenge, blood and excreta samples were collected from each pigs for analysis. Fecal scores were measured on d 7, 14, 21, and 28 of the study.ResultsIn Exp. 1, overall BW, average daily gain (ADG), gain/feed (G/F) ratio, and nutrient digestibilities were lower (P < 0.05) in CON group compared with the nucleotides fed pigs. In Exp. 2, after challenge, IgA, IgM, and IGF-I were higher (P < 0.05) in the nucleotide groups compared with CON. However, the nucleotide groups had lower (P < 0.05) cortisol and TNF-α compared with CON. Fecal E. coli counts and fecal score for the nucleotide groups were lower (P < 0.05) than for CON.ConclusionsIn conclusion, dietary nucleotides supplementation could improve growth performance, nutrient digestibility, immune status, microbial balance, reduce diarrhea, and provide protection against enterotoxigenic E. coli K88 infection in weanling pigs.

A Study on effectiveness of a cocktail of protected feed additives in growing pigs

“…Diets containing nucleotides can maintain stable microbiota in the ileum (Li et al 2015), which is in line with the finding of the present study showing increased fecal Lactobacillus and decreased E. coli in groups treated with nucleotides. It has been reported that pigs with pathogenic E. coli infection fed with dietary supplements of nucleotides have reduced diarrhoea and improved weight gain and feed conversion ratio compared to pigs fed with control diet (Li et al 2015).…”

“…Further, when 3% of MFA was added to diets, levels of cortisol (P=0.032) and LDL/C (P=0.008) were significantly reduced at the end of week 4. However, there was no significantly difference (P>0.05) in HDL/C, or total cholesterol among dietary treatments (Table 3) and which are in agreement with previous studies (Li et al 2015;Upadhaya et al 2015a;Upadhaya et al 2015b;Mohana Devi et al 2016;Upadhaya et al 2016), who reported that dietary supplements with those protected feed additives. Similarly, Gaines et al (2003) have also reported that inclusion of menhaden fish oil (containing omega-3) in diet have reduced serum cortisol levels in immune system activated pigs.…”

“…The result indicates that vaccination at the age of 8 week, the level of antibody increases rapidly within 4 weeks from the date of vaccine administration with dietary supplementation of MFA. It has been reported that MFA supplementation has positive effect on systemic immunity and can increase serum antibody (Nagafuchi et al 1997) and cortisol levels (Li et al 2015). Based on literature (Chinsangaram et al 1998;Doel 1999;Yu et al 2002), the optimum FMD neutralizing antibody titre normally appears after the first vaccination at week 3.…”

“…They may protect acids from release in the upper part of the digestive tract (NRC, 2012). Results of previous experiments indicated that dietary inclusion of protected OA (Upadhaya et al 2015b;Mohana Devi et al 2016;Lei et al 2017), omega-3 (Upadhaya et al 2015a;Upadhaya et al 2016), amino acids (Kumar et al 2012) and nucleotides (Li et al 2015) had positive effects on growth performances of pigs. However, some studies have reported that dietary supplementation with omega-3 (Kouba et al 2003;Cho and Kim, 2013) or a blend of OA and nucleotides (Lee et al 2007) had no effect on growth performance of growing pigs.…”

“…Following the ban of antibiotics as growth promoters due to the development of antimicrobial resistance in pathogens, alternative methods are needed to improve the growth and efficiency of pig production. This has prompted scientific investigation on feed additives and their abilities to positively alter gut health and function (Yan and Kim, 2013;Suryanarayana and Suresh, 2014;Li et al 2015). Some feed additives such as organic acids (OA), amino acids (AA), omega-3 fatty acids and nucleotides have been used to improve swine nutrition and their principle biological effects have been identified.…”