Nutritional and functional roles of ß-mannanase on intestinal health and growth of newly weaned pigs fed two different types of feeds.

This study aimed to investigate the nutritional and functional roles of ß-mannanase on the intestinal health and growth of newly weaned pigs fed a typical or low-cost formulated feeds (LCF). Twenty-four newly weaned pigs at 6.2 kg ±â€…0.4 body weight (BW) were allotted to three dietary treatments based on a randomized complete block design with sex and initial BW as blocks. Three dietary treatments are as follows: Control, typical nursery feeds including animal protein supplements and enzyme-treated soybean meal; LCF with increased amounts of soybean meal, decreased amounts of animal protein supplements, and no enzyme-treated soybean meal; LCF+, low-cost formulated feed with ß-mannanase at 100 g/t, providing 800 thermostable ß-mannanase unit (TMU) per kg of feed. Pigs were fed based on a three-phase feeding program for a total of 37 d. On day 37 of feeding, all pigs were euthanized and the gastrointestinal tract was removed for sample collection to analyze intestinal health parameters, mucosa-associated microbiota, and gene expression of tight junction proteins. Pigs fed LCF increased (P < 0.05) the relative abundance of Proteobacteria and Helicobacter in the jejunal mucosa, tended to decrease (P = 0.097; P = 0.098) the concentration of malondialdehyde (MDA) and the expression of zona occluden 1 (ZO-1) gene in the jejunum, tended to decrease average daily gain (ADG; P = 0.084) and final BW (P = 0.090), and decreased (P < 0.05) average daily feed intake. Pigs fed LCF + tended to decrease (P = 0.088) digesta viscosity, decreased (P < 0.05) the relative abundance of Helicobacter, and increased (P < 0.05) Lactobacillus in the jejunal mucosa compared to LCF. Additionally, LCF + tended to increase final BW (P = 0.059) and ADG (P = 0.054), increased (P < 0.05) gain to feed ratio (G:F), and reduced (P < 0.05) fecal score compared to LCF. LCF with decreased amounts of animal protein supplements and increased amounts of soybean meal had negative effects on the composition of the mucosa-associated microbiota, intestinal integrity, and growth performance of nursery pigs. Beta-mannanase supplementation to LCF decreased digesta viscosity, increased the relative abundance of potentially health-benefitting microbiota such as Lactobacillus, and improved growth and fecal score, thus reflecting its efficacy in low-cost formulated feeds with increased amounts of soybean meal.

Immediately following weaning, pigs are exposed to various stressors associated with environmental, social, and dietary shifts that can result in depressed growth, high incidence of diarrhea, and increases in mortality. Major plant-based feedstuffs such as soybean meal contain anti-nutritional compounds including nonstarch polysaccharides causing negative impacts on the intestinal health and growth of nursery pigs due to the immaturity of the intestine and intestinal immune system. ß-mannanase hydrolyzes ß-mannans, nonstarch polysaccharides, resulting in elimination of anti-nutritional properties and the release of mannooligosaccharides. The aim of this study was to investigate the nutritional and functional roles of ß-mannanase on intestinal health and growth of newly weaned pigs fed a low-cost formulated feed (LCF). This study showed that increased amounts of soybean meal in LCF increased pathogenic bacteria associated to the jejunal mucosa of nursery pigs, impaired intestinal integrity, and decreased growth. Supplementation of ß-mannanase to LCF decreased digesta viscosity, increased Lactobacillus in the jejunal mucosa, reduced diarrhea, and improved growth performance of nursery pigs.

Safety of dietary nitrate supplementation by calcium nitrate for finishing pigs as measured by methemoglobin and serum and tissue nitrate levels.

Nitrate supplementation has been studied as a beneficial constituent of the human diet, particularly for its effects on vascular health through vasodilation. Recent studies have focused on the benefits of nitrate supplementation in animals, especially in swine. Up to 1,200 mg/kg dietary nitrate supplementation from Ca nitrate was beneficial in farrowing and lactating sows and their offspring, and up to 6,000 mg/kg supplemental nitrate showed no adverse health effects in sows or piglets. Controlled study data evaluating the safety of nitrate supplementation to growing swine of any weight class is scant. Therefore, an experiment was conducted to test the hypothesis that increased inclusion rates of dietary nitrate through the addition of Ca nitrate in diets would not influence concentrations of nitrate or nitrite in serum and tissue, nor blood hemoglobin and methemoglobin. Forty-eight individually housed pigs (initial weight 119.1 ±â€…5.3 kg) were randomly allotted to four dietary treatments containing 0, 500, 1,000, or 2,000 mg/kg dietary nitrate and fed experimental diets for 28 d. Growth performance was not influenced (P > 0.10) by dietary treatment. The most sensitive safety endpoint, methemoglobin, did not change (P > 0.10) with dietary nitrate exposure up to 2,000 mg/kg. Serum and tissue nitrate and nitrite levels, myoglobin, and hemoglobin were not adversely affected (P > 0.10). Total myoglobin in the loin linearly increased (P < 0.05) with greater dietary nitrate in the diet, which is correlated with the red color of meat. This work established the safety of up to 2,000 mg/kg dietary nitrate from Ca nitrate as an ingredient in food for finishing pigs.

Performance response of increasing the standardized ileal digestible tryptophan:lysine ratio in diets containing 40% dried distiller grains with solubles.

A total of 1,170 pigs (PIC 800 × PIC, initially 38.6 kg) were used in a 98-d grow-finish study to determine the performance response of pigs fed increasing levels standardized ileal digestible (SID) Trp:Lys ratio in diets containing 40% dried distillers grains with solubles (DDGS). Five dietary treatments were fed and consisted of a corn-soybean meal (SBM) diet or diets containing 40% DDGS with SID Trp:Lys ratios of 15%, 18%, 21%, or 24%. Each treatment was replicated 9 times and pens contained 26 pigs with the equal number of gilts and barrows. Data was analyzed as a randomized complete block design with previous nursery treatment as a random blocking factor. Pair-wise comparisons were used to evaluate the impact of diets on performance and carcass traits; specifically to compare the corn-SBM dietary treatment against other dietary treatments. Single degree of freedom orthogonal polynomials were used to evaluate the dose-response of increasing the SID Trp:Lys ratio in 40% DDGS diets. Increasing the SID Trp:Lys ratio in diets containing 40% DDGS increased (linear, P ≤ 0.02) average daily gain (ADG), average daily feed intake (ADFI), final body weight (BW), hot carcass weight (HCW), carcass gain, and daily carcass gain. Increasing the SID Trp:Lys ratio in 40% DDGS diets did not impact (P ≥ 0.65) gain to feed (G:F) for the cumulative period. Pigs fed the corn-SBM diet had greater (P ≤ 0.01) ADG and a heavier (P ≤ 0.01) final BW compared to pigs fed 40% DDGS diets, regardless of the SID Trp:Lys ratio. Diets that contained 40% DDGS with a SID Trp:Lys ratio of 24% had no difference (P|t| = 0.25) in ADFI compared to the corn-SBM dietary treatment. The cumulative G:F of pigs did not differ (P = 0.32) between pigs fed corn-SBM diets and diets containing 40% DDGS regardless of the SID Trp:Lys ratio. However, pigs receiving the corn-SBM diets had heavier HCW, greater carcass yields, total carcass gain, and daily carcass gain (P < 0.01) compared to pigs fed the 40% DDGS diets regardless of SID Trp:Lys ratio. In conclusion, increasing the SID Trp:Lys ratio in 40% DDGS diets improved ADG and ADFI for the overall grow-finish period. However, when compared to a corn-SBM diet, increasing the SID Trp:Lys ratio in 40% DDGS diets did not correct the growth performance or carcass characteristics of pigs.

Corn by-products from the ethanol industry, such as dried distillers grains with solubles (DDGS), can be an economical feed ingredient in pig rations. However, when pigs are fed high dietary levels of DDGS, their growth performance can decrease. This decrease may be a result of the protein composition of the diet and more specifically the dietary amino acid composition. In the present study, the amino acid, tryptophan, was incrementally increased in diets containing 40% DDGS. The increase in dietary tryptophan resulted in increased pig feed intake and growth rate of pigs. These results suggest that increasing the dietary tryptophan level can help mitigate a portion of the decreased growth performance seen by pigs consuming higher dietary levels of DDGS. However, feeding 40% DDGS still resulted in a lower cumulative growth rate compared to a standard corn soybean meal diet. This indicates that other nutritional strategies are required to restore growth the performance of pigs fed 40% DDGS relative to a standard corn soybean meal diet, but increasing dietary tryptophan can help to partially restore growth performance.

Effects of water quality on growth performance and health of nursery pigs.

An experiment was conducted to determine the effects of providing drinking water of differing qualities on growth performance and health of nursery pigs. Weanling pigs (n = 450; 150 pigs/group; 10 pigs/pen) were assigned randomly to one of three experimental groups consisting of three water sources of varying qualities: 1) Water source A containing 1,410 ppm hardness (CaCO3 equivalent), 1,120 ppm sulfates, and 1,500 ppm total dissolved solids (TDS); 2) Water source B containing 909 ppm hardness (CaCO3 equivalent), 617 ppm sulfates, and 1,050 ppm TDS; and 3) Water source C containing 235 ppm hardness (CaCO3 equivalent), 2 ppm sulfates, and 348 ppm TDS. Pigs were provided ad libitum access to their respective water sources for the duration of the study which began at weaning (21 d of age) and ended 40 d later (61 d of age). Individual pig weights were recorded weekly along with feed intake on a pen basis. Occurrences of morbidity and mortality were recorded daily. Subjective fecal scores were assigned on a pen basis and blood samples were used to evaluate blood chemistry, cytokine concentrations, and phagocytic activity. A differential sugar absorption test was used to assess intestinal permeability. Fecal grab samples were used to establish diet digestibility, and drinking behavior was video-recorded to assess pigs' acceptance of water sources provided. The statistical model considered fixed effects of water source, room, and their interaction with the random effect of pen. A repeated measures analysis was conducted to determine the effects of water quality over time. There were no differences (P > 0.440) among water sources in average daily gain (A, 0.46 kg/d; B, 0.46 kg/d; C, 0.47 kg/d) or average daily feed intake (A, 0.68 kg/d; B, 0.69 kg/d; C, 0.71 kg/d). Overall mortality of pigs was 0.44% and did not differ across the three water sources. There were no differences in apparent total tract digestibility of the diet, intestinal permeability, immune parameters, or blood chemistry attributable to quality of water consumed by pigs. Pigs did not show an aversion to the water sources provided, because total time pigs spent at the drinker did not differ (P > 0.750) among water sources on days 1 through 3 of the experiment. These data indicate that the water sources of differing quality studied did not affect growth performance or health of nursery pigs.