Maintenance of villus height and crypt depth, and enhancement of disaccharide digestion and monosaccharide absorption, in piglets fed on cows' whole milk after weaning

Effects of protein supplementation on Nellore cows’ reproductive performance, growth, myogenesis, lipogenesis and intestine development of the progeny

Context It is hypothesised that protein supplementation in pregnant Nellore cows during the dry season would improve reproductive performance in the next breeding season, as well as growth, myogenesis and intramuscular lipogenesis of the progeny until weaning. Aims To evaluate the effect of maternal nutrition on cow reproductive performance, as well as on the growth, myogenesis and lipogenesis of the progeny until weaning. Methods A total of 92 pregnant cows were fed on pasture, and half of the cows were also fed a mineral–protein supplement (36% crude protein) from 124 ± 21 days of pregnancy to calving. Therefore, two treatments were tested: non-supplemented or supplemented cows. Progeny were weighed after birth, 130 days after birth and at weaning. Six newborn calves from each treatment were slaughtered to collect muscle and jejunum samples to analyse histology and gene expression. In addition, Longissimus thoracis muscle biopsies were collected at 11 days after birth and weaning for gene expression analyses. Key results Supplemented cows had greater bodyweight (P = 0.03) and body condition score (P = 0.05) during gestation, and the pregnancy rate in the subsequent breeding season had a tendency (P = 0.10) to be greater. The progeny from supplemented cows had greater bodyweight at birth (P = 0.05). However, no differences (P > 0.05) were found in bodyweight at weaning or in the average daily gain during this period. Non-supplemented calves had greater SLC27A4 (P = 0.04) expression and a tendency for greater expression of SLC5A1 (P = 0.08) in the jejunum. Muscle gene expression data showed that progeny from supplemented cows had greater expression of myogenic (WNT10B), adipogenic (PPARG, ZFP423, CD36) and fibrogenic (TGFβ1) markers at birth and at weaning (P ≤ 0.10). Conclusions In conclusion, protein supplementation of pregnant Nellore cows leads to positive effects for subsequent reproductive performance and for muscle development of their progeny. In addition, the progeny from feed-restricted cows increases prenatal intestinal development for better nutrients absorption under a potentially impaired environmental condition. Implications The use of protein supplementation in pregnant Nellore cows has a positive impact on the production system, increasing productivity in a cow/calf operation.

Effects of dietary iron level on growth performance, hematological status, and intestinal function in growing-finishing pigs

This study investigated the different addition levels of iron (Fe) in growing-finishing pigs and the effect of different Fe levels on growth performance, hematological status, intestinal barrier function, and intestinal digestion. A total of 1,200 barrows and gilts ([Large White × Landrace] × Duroc) with average initial body weight (BW; 27.74 ± 0.28 kg) were housed in 40 pens of 30 pigs per pen (gilts and barrows in half), blocked by BW and gender, and fed five experimental diets (eight replicate pens per diet). The five experimental diets were control diet (basal diet with no FeSO4 supplementation), and the basal diet being supplemented with 150, 300, 450, or 600 mg/kg Fe as FeSO4 diets. The trial lasted for 100 d and was divided into the growing phase (27 to 60 kg of BW) for the first 50 d and the finishing phase (61 to 100 kg of BW) for the last 50 d. The basal diet was formulated with an Fe-free trace mineral premix and contained 203.36 mg/kg total dietary Fe in the growing phase and 216.71 mg/kg in the finishing phase based on ingredient contributions. And at the end of the experiment, eight pigs (four barrows and four gilts) were randomly selected from each treatment (selected one pig per pen) for digesta, blood, and intestinal samples collection. The results showed that the average daily feed intake (P = 0.025), average daily gain (P = 0.020), and BW (P = 0.019) increased linearly in the finishing phase of pigs fed with the diets containing Fe. On the other hand, supplementation with different Fe levels in the diet significantly increased serum iron and transferrin saturation concentrations (P < 0.05), goblet cell numbers of duodenal villous (P < 0.001), and MUC4 mRNA expression (P < 0.05). The apparent ileal digestibility (AID) of amino acids (AA) for pigs in the 450 and 600 mg/kg Fe groups was greater (P < 0.05) than for pigs in the control group. In conclusion, dietary supplementation with 450 to 600 mg/kg Fe improved the growth performance of pigs by changing hematological status and by enhancing intestinal goblet cell differentiation and AID of AA.

Pretreatment with probiotics ameliorate gut health and necrotic enteritis in broiler chickens, a substitute to antibiotics

Necrotic enteritis (NE) is being considered as one of the most important intestinal diseases in the recent poultry production systems, which causes huge economic losses globally. NE is caused by Clostridium perfringens, a pathogenic bacterium, and normal resident of the intestinal microflora of healthy broiler chickens. Gastrointestinal tract (GIT) of broiler chicken is considered as the most integral part of pathogen's entrance, their production and disease prevention. Interaction between C. perfringens and other pathogens such as Escherichia coli and Salmonella present in the small intestine may contribute to the development of NE in broiler chickens. The antibiotic therapy was used to treat the NE; however European Union has imposed a strict ban due to the negative implications of drug resistance. Moreover, antibiotic growth promoters cause adverse effects on human health as results of withdrawal of antibiotic residues in the chicken meat. After restriction on use of antibiotics, numerous studies have been carried out to investigate the alternatives to antibiotics for controlling NE. Thus, possible alternatives to prevent NE are bio-therapeutic agents (Probiotics), prebiotics, organic acids and essential oils which help in nutrients digestion, immunity enhancement and overall broiler performance. Recently, probiotics are extensively used alternatives to antibiotics for improving host health status and making them efficient in production. The aim of review is to describe a replacement to antibiotics by using different microbial strains as probiotics such as bacteria and yeasts etc. having bacteriostatic properties which inhibit growth of pathogens and neutralize the toxins by different modes of action.

Effects of soybean isoflavones on the growth performance, intestinal morphology and antioxidative properties in pigs

Soybean meal is rich in soybean isoflavones, which exhibit antioxidant, anti-inflammatory, antiviral and anticancer functions in humans and animals. This study was conducted to investigate the effects of soybean isoflavones on the growth performance, intestinal morphology and antioxidative properties in pigs. A total of 72 weaned piglets (7.45 ± 0.13 kg; 36 males and 36 females) were allocated into three treatments and fed corn-soybean meal (C-SBM), corn-soy protein concentrate (C-SPC) or C-SPC supplemented with equal levels of the isoflavones found in the C-SBM diet (C-SPC + ISF) for a 72-day trial. Each treatment had six replicates and four piglets per replicate, half male and half female. On day 42, one male pig from each replicate was selected and euthanized to collect intestinal samples. The results showed that compared to pigs fed the C-SPC diet, pigs fed the C-SBM and C-SPC + ISF diets had higher BW on day 72 (P < 0.05); pigs fed the C-SBM diet had significantly higher average daily gain (ADG) during days 14 to 28 (P < 0.05), with C-SPC + ISF being intermediate; pigs fed the C-SBM diet tended to have higher ADG during days 42 to 72 (P = 0.063), while pigs fed the C-SPC + ISF diet had significantly higher ADG during days 42 to 72 (P < 0.05). Moreover, compared to pigs fed the C-SPC diet, pigs fed the C-SBM diet tended to have greater villus height (P = 0.092), while pigs fed the C-SPC + ISF diet had significantly greater villus height (P < 0.05); pigs fed the C-SBM and C-SPC + ISF diets had significantly increased villus height-to-crypt depth ratio (P < 0.05). Compared with the C-SPC diet, dietary C-SPC + ISF tended to increase plasma superoxide dismutase activity on days 28 (P = 0.085) and 42 (P = 0.075) and reduce plasma malondialdehyde (MDA) content on day 42 (P = 0.089), as well as significantly decreased jejunal mucosa MDA content on day 42 (P < 0.05). However, no significant difference in the expression of tight junction genes among the three groups was found (P > 0.05). In conclusion, our results suggest that a long-term exposure to soybean isoflavones enhances the growth performance, protects the intestinal morphology and improves the antioxidative properties in pigs.

Dietary supplementation with citrus extract alters the plasma parameters, circulating amino acid profiles and gene expression of small intestinal nutrient transporters in Chinese yellow-feathered broilers

BACKGROUND

This study evaluated the effects of citrus extract (CE) on growth performance, plasma amino acid (AA) profiles, intestinal development and small intestine AA and peptide transporter expression levels in broilers. A total of 540 one-day-old yellow-feathered broilers were fed a basal diet without any antibiotic (control group), or a basal diet containing 10 mg kg^-1 zinc bacitracin (antibiotic group), or a basal diet supplemented with 10 mg kg^-1 CE (CE group). After 63 days of feeding, two broilers per pen were slaughtered to collect tissues for further analysis.

RESULTS

Results showed that CE increased (P < 0.05) the final body weight and average daily gain from day 1 to 63, and decreased (P < 0.05) the feed/gain ratio from day 1 to 63. Dietary CE supplementation increased (P < 0.05) plasma total protein, albumin and glucose concentration, and decreased (P < 0.05) urea concentration. CE supplementation increased (P < 0.05) the villus height in the ileum and the villus height/crypt depth in the jejunum and ileum, but decreased (P < 0.05) the crypt depth in the jejunum and ileum. CE supplementation increased (P < 0.05) most plasma essential AA concentrations. Additionally, CE supplementation upregulated (P < 0.05) ASCT1, b^0,+ AT, B⁰ AT1, EAAT3, rBAT, y⁺ LAT2 and PepT1 expression in the jejunum, and b^0,+ AT, EAAT3, rBAT, y⁺ LAT2, CAT1 and PepT1 in the ileum.

CONCLUSIONS

Collectively, our results indicated that CE supplementation promotes intestinal physiological absorption of AAs by upregulating gene expression of small intestinal key AA and peptide transporters, thereby enhancing the growth performance of broilers. © 2020 Society of Chemical Industry.

Benzoic Acid Combined with Essential Oils Can Be an Alternative to the Use of Antibiotic Growth Promoters for Piglets Challenged with E. coli F4

Simple Summary

The use of antibiotics as growth promoters for swine must be minimized as it can promote resistance in microorganisms. Therefore, it is essential to search for alternative additives. This study aimed to investigate the effects of benzoic acid and a blend of essential oils (thymol, 2-methoxyphenol, eugenol, piperine, and curcumin) on the performance and intestinal health of weanling piglets challenged with Escherichia coli F4. The combination of benzoic acid and essential oils at 3 g/kg improved the piglets’ average daily gain and consequently their final body weight and it is an economically viable alternative to replace colistin. These results could have a great impact on society, contributing to the one heath concept and demonstrating the ability to replace antibiotics as growth promoters and thus minimize the chance of causing bacteria resistance.

Abstract

Benzoic acid (BA) and essential oils (EOs) (thymol, 2-methoxyphenol, eugenol, piperine, and curcumin) are being studied to minimize the impairment of gastrointestinal functions in weanling piglets. This study evaluates the effects of combining BA and EO on the performance and intestinal health of piglets challenged with E. coli F4 (1 mL, 10⁶ CFU/mL). In total, 270 weaned piglets were used in a randomized block design with six treatments: positive control, with 40 mg/kg colistin (PC); negative control, without the growth promoter (NC); negative control +5 g/kg benzoic acid (BA); negative control +2 g/kg combination of BA+EO (BA+EO2); negative control +3 g/kg combination of BA+EO (BA+EO3); negative control +4 g/kg combination of BA+EO (BA+EO4). BA+EO3 presented a greater average daily gain (ADG) (p = 0.0013) and better feed-to-gain ratio (p = 0.0138), compared to NC, from 21 to 35 days age. For the total period, BA, BA+EO3, and BA+EO4 were similar to PC and superior to NC for ADG (p = 0.0002) and final body weight (BW) (p = 0.0002). No difference (p > 0.05) was verified for diarrhea, microbial population, production of volatile fatty acids, pH, weight of organs, cellular proliferation, and cholecystokinin count. NC and BA+EO4 resulted in a higher villus height in the jejunum (p = 0.0120) compared to BA+EO3. The use of BA or the combination of BA and EO at 3 g/kg provides improved performance, aside from being an economically viable alternative to replace colistin.

Dietary Bacillus spp. enhanced growth and disease resistance of weaned pigs by modulating intestinal microbiota and systemic immunity

Background

Previous research has shown that dietary supplementation of Bacillus spp. probiotics exerts beneficial effects on animals' growth. However, limited studies have evaluated the efficacy of Bacillus spp. on weaned pigs and their effects on host gut health and microbiome, and systemic immunity using a disease challenge model. The objective of this experiment was to investigate the effects of two Bacillus spp. strains (Bacillus subtilis DSM 32540 and Bacillus pumilus DSM 32539) on growth performance, diarrhea, intestinal health, microbiome, and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli (ETEC).

Results

Pigs in PRO1 (Bacillus subtilis DSM 32540) had greater (P < 0.05) body weight on d 7 and 14 PI, greater (P < 0.05) ADG from d 0 to 7 and d 7 to 14 PI, compared with pigs in CON (Control). Pigs in PRO1 had milder (P < 0.05) diarrhea on d 2 and 3 PI compared with pigs in CON. However, no differences were observed in growth performance and diarrhea score between PRO2 (Bacillus pumilus DSM 32539) and CON groups. Supplementation of PRO1 decreased (P < 0.05) lymphocyte counts on d 7 and 14 PI, compared with CON. Supplementation of PRO1 and PRO2 both reduced (P < 0.05) total coliforms in mesenteric lymph nodes on d 21 PI. Pigs in PRO2 had greater (P < 0.05) goblet cell number and sulfomucin percentage in duodenal villi and greater (P < 0.05) sialomucin percentage in jejunal villi than pigs in CON. Supplementation of PRO1 up-regulated (P < 0.05) MUC2 gene expression in jejunal mucosa and reduced (P < 0.05) PTGS-2 and IL1B gene expression in ileal mucosa on d 21 PI, compared with CON. Pigs in PRO1 had reduced (P < 0.05) relative abundance of families Lachnospiraceae, Peptostreptococcaceae and Pasteurellaceae in the ileum.

Conclusions

Supplementation of Bacillus subtilis DSM 32540 improved growth performance, alleviated diarrhea severity, enhanced gut health, and reduced systemic inflammation of weaned pigs infected with ETEC F18. Although Bacillus pumilus DSM 32539 was able to alleviate systemic inflammation, it had limited impacts on growth performance and severity of diarrhea of ETEC F18 challenged weaned pigs.

Growth performance and gut health of Escherichia coli-challenged weaned pigs fed diets supplemented with a Bacillus subtilis direct-fed microbial

This study was conducted to investigate the effects of a direct-fed microbial (DFM) product (Bacillus subtilis strain DSM 32540) in weaned pigs challenged with K88 strain of Escherichia coli on growth performance and indicators of gut health. A total of 21 weaned pigs [initial body weight (BW) = 8.19 kg] were housed individually in pens and fed three diets (seven replicates per diet) for 21 d in a completely randomized design. The three diets were a corn-soybean meal-based basal diet without feed additives, a basal diet with 0.25% antibiotics (neo-Oxy 10-10; neomycin + oxytetracycline), or a basal diet with 0.05% DFM. All pigs were orally challenged with a subclinical dose (6.7 × 10⁸ CFU/mL) of K88 strain of E. coli on day 3 of the study (3 d after weaning). Feed intake and BW data were collected on days 0, 3, 7, 14, and 21. Fecal scores were recorded daily. On day 21, pigs were sacrificed to determine various indicators of gut health. Supplementation of the basal diet with antibiotics or DFM did not affect the overall (days 0-21) growth performance of pigs. However, antibiotics or DFM supplementation increased (P = 0.010) gain:feed (G:F) of pigs during the post-E. coli challenge period (days 3-21) by 23% and 24%, respectively. The G:F for the DFM-supplemented diet did not differ from that for the antibiotics-supplemented diet. The frequency of diarrhea for pigs fed a diet with antibiotics or DFM tended to be lower (P = 0.071) than that of pigs fed the basal diet. The jejunal villous height (VH) and the VH to crypt depth ratio (VH:CD) were increased (P < 0.001) by 33% and 35%, respectively, due to the inclusion of antibiotics in the basal diet and by 43% and 41%, respectively due to the inclusion of DFM in the basal diet. The VH and VH:CD for the DFM-supplemented diet were greater (P < 0.05) than those for the antibiotics-supplemented diet. Ileal VH was increased (P < 0.05) by 46% due to the inclusion of DFM in the basal diet. The empty weight of small intestine, cecum, or colon relative to live BW was unaffected by dietary antibiotics or DFM supplementation. In conclusion, the addition of DFM to the basal diet improved the feed efficiency of E. coli-challenged weaned pigs to a value similar to that of the antibiotics-supplemented diet and increased jejunal VH and VH:CD ratio to values greater than those for the antibiotics-supplemented diet. Thus, under E. coli challenge, the test DFM product may replace the use of antibiotics as a growth promoter in diets for weaned pigs to improve feed efficiency and gut integrity.

Protein Level and Infantile Diarrhea in a Postweaning Piglet Model

Infantile diarrhea is a serious public health problem around worldwide and results in millions of deaths each year. The levels and sources of dietary protein are potential sources of diarrhea, but the relationship between the pathogenesis causes of infantile diarrhea and protein intake remains poorly understood. Many studies have indicated that the key to understanding the relationship between the protein in the diet and the postweaning diarrhea of piglets is to explore the influences of protein sources and levels on the mammalian digestion system. The current study was designed to control diarrhea control by choosing different protein levels in the diet and aimed at providing efficient regulatory measures for infantile diarrhea by controlling the protein levels in diets using a postweaning piglets model. To avoid influences from other protein sources, casein was used as the only protein source in this study. Fourteen piglets (7.98 ± 0.14 kg, weaned at 28 d) were randomly allotted to two dietary treatments: a control group (Cont, containing 17% casein) and a high protein group (HP, containing 30% casein). The experiment lasted for two weeks and all animals were free to eat and drink water ad libitum. The diarrhea score (1 = normal; 3 = watery diarrhea) and growth performance were recorded daily. The results showed that the piglets in HP group had persistent diarrhea during the whole study, while no diarrhea was noticed in the control groups. Also, the feed intake and body weights were reduced in the HP groups compared with the other group (P < 0.05). The diarrhea-related mRNA abundances were analyzed by real-time PCR; the results showed that HP treatment markedly decreased the expression of aquaporin (AQP, P < 0.05) and the tight junction protein (P<0.05), but increased inflammatory cytokines (P < 0.01) than those in control group. In addition, the Adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway (P < 0.01) was inhibited in the HP group. Intestinal microbiota was tested by 16S sequencing, and we found that the HP group had a low diversity compared the other group. In conclusion, despite being highly digestible, a high casein diet induced postweaning diarrhea and reduced the growth performance of the postweaning piglets. Meanwhile, AQP, tight junction protein, and intestinal immune were compromised. Thus, the mechanism of how a highly digestible protein diet induces diarrhea might be associated with the AMPK signaling pathway and intestinal microbiome.

The dietary combination of essential oils and organic acids reduces Salmonella enteritidis in challenged chicks

This study was conducted to determine the effects of essential oils and organic acids (EOA) on Salmonella Enteritidis (S. Enteritidis) challenged chickens. One-day-old specific pathogen-free (SPF) chicks (250) were randomly assigned to 5 groups, with 50 birds in each group. The treatment groups were as follows: 1) basal diet, negative control group (NC); 2) basal diet + S. Enteritidis, positive control group (PC); 3) PC + 4,000 g/t of enrofloxacin (5%), antibiotic group (ENR); 4) PC + 800 g/t of EOA1, thymol-benzoic acid group (TBA); and 5) PC + 800 g/t of EOA2, cinnamylaldehyde-caproic acid group (CCA). At 7 D of age, each bird, except those in NC, was orally gavaged with 0.4 mL of a suspension of 4.4 × 10⁹ cfu S. Enteritidis/mL. Results revealed that ENR reduced bacterial counts in the liver and spleen on days 3, 5, and 7 post-challenge more (P < 0.05) than any other treatments. However, bacterial counts in cecal contents among ENR, TBA, and CCA were similar at 5 and 7 D post-challenge but lower than those of PC. Additionally, the bacterial counts in liver, spleen, and cecum contents in TBA were lower (P < 0.05) than in PC at 3, 5, and 7 D post-challenge; the bacterial counts in spleen contents in TBA were lower (P < 0.05) than in CCA at 7 D post-challenge. Tumor necrosis factor-α contents in TBA and CCA were lower (P < 0.05) than those in PC. Also, the ratio of villus height to crypt depth in the ileum of CCA was higher (P < 0.05) than that of PC and ENR; however, there was no difference in the secretory IgA content of the jejunum among the groups. In conclusion, EOA had a bacteriostatic effect on S. Enteritidis, and the effect of the thymol-benzoic acid complex surpassed that of the cinnamaldehyde-caproic acid complex. Therefore, EOA may act as an effective antibiotic substitute for animals in the prevention and treatment of Salmonella.

Effects of in ovo feeding of N-acetyl-L-glutamate on early intestinal development and growth performance in broiler chickens

The present study determined the effects of in ovo feeding (IOF) of N-acetyl-L-glutamate (NAG) on early intestinal development and growth performance of broilers. A total of 702 fertile broiler eggs were randomly divided into 3 treatments: 1) non-punctured control group, 2) saline-injected control group, and 3) NAG solution-injected group (1.5 mg/egg). At 17.5 D of incubation, 300 μL of each solution was injected into each egg of injected groups. Results indicated that the hatchability and healthy chicken rate were not affected by NAG injection (P > 0.05). Chicks from NAG solution-injected group had significantly decreased average daily feed intake and feed conversion ratio during 1-14 D than those in the non-punctured control group (P < 0.05). Compared with the non-punctured control group, IOF of NAG significantly increased the density of goblet cells in jejunum at hatch, duodenum at 7 D, and ileum at 14 D; decreased crypt depth in jejunum at hatch; and increased villus height in duodenum and jejunum and villus height:crypt depth ratio in duodenum at 7 D (P < 0.05). The intestinal mRNA expression of Na⁺-dependent neutral amino acid transporter, peptide transporter, and excitatory amino acid transporter 3 did not differ between groups at 7 or 14 D. However, the mRNA expression level of rBAT in jejunum significantly increased in the NAG solution-injected group than in the non-punctured control group at 7 D (P < 0.05). In conclusion, IOF of NAG (1.5 mg/egg) accelerated the early intestinal development by enhancing intestinal immune and absorption function, thereby positively affecting the feed efficiency for the first 2 wk post-hatch.

Effects of dietary grape pomace on the intestinal microbiota and growth performance of weaned piglets

Grape pomace (GP) is an abundant by-product from wine production and is rich in phenolic compounds, unsaturated fatty acids, dietary fibre and beneficial bacteria. In this study, weaned piglets were fed a basic diet supplemented with 5% GP for 4 weeks. Compared with those in the control (CON) group, it was found that the proportion of Lactobacillus delbrueckii, Olsenella umbonata and Selenomonas bovis in the caecum and the villus height and villus height/crypt depth ratio (VCR) of the jejunum were both significantly increased in the GP group (p < 0.05). Meanwhile, at the mRNA expression level, several proinflammatory cytokines (IL-1β, IL-8, IL-6 and TNF-α) were significantly downregulated (p < 0.05) in piglet caecal tissue, and the short-chain fatty acid receptors (GPR41 and GPR43) were not significantly upregulated. In contrast, the levels of IgG was significantly increased (p < 0.05) in the sera of weaned piglets in the GP group. However, no difference in growth performance between the two groups of piglets was detected. These results show that GP had no adverse effects on the growth performance of piglets, but GP can promote the content of some beneficial bacteria in the caecum; this effect is conducive to improving the disease resistance potential of piglets.

Effects of dietary inulin supplementation on growth performance, intestinal barrier integrity and microbial populations in weaned pigs

Here, we explored the influences of dietary inulin (INU) supplementation on growth performance and intestinal health in a porcine model. Thirty-two male weaned pigs (with an average body weight of 7·10 (sd 0·20) kg) were randomly assigned to four treatments and fed with a basal diet (BD) or BD containing 2·5, 5·0 and 10·0 g/kg INU. After a 21-d trial, pigs were killed for collection of serum and intestinal tissues. We show that INU supplementation had no significant influence on the growth performance in weaned pigs. INU significantly elevated serum insulin-like growth factor-1 concentration but decreased diamine oxidase concentration (P < 0·05). Interestingly, 2·5 and 5·0 g/kg INU supplementation significantly elevated the villus height in jejunum and ileum (P < 0·05). Moreover, 2·5 and 5·0 g/kg INU supplementation also elevated the villus height to crypt depth (V:C) in the duodenum and ileum and improved the distribution and abundance of tight-junction protein zonula occludens-1 in duodenum and ileum epithelium. INU supplementation at 10·0 g/kg significantly elevated the sucrase activity in the ileum mucosa (P < 0·05). INU supplementation decreased the expression level of TNF-α but elevated the expression level of GLUT 2 and divalent metal transporter 1 in the intestinal mucosa (P < 0·05). Moreover, INU increased acetic and butyric acid concentrations in caecum (P < 0·05). Importantly, INU elevated the Lactobacillus population but decreased the Escherichia coli population in the caecum (P < 0·05). These results not only indicate a beneficial effect of INU on growth performance and intestinal barrier functions but also offer potential mechanisms behind the dietary fibre-regulated intestinal health.

Effect of Antibiotic, Phytobiotic and Probiotic Supplementation on Growth, Blood Indices and Intestine Health in Broiler Chicks Challenged with Clostridium perfringens

Simple Summary

Necrotic enteritis is one of the most important economic issues in the poultry industry, associated with sudden death rates of up to 50%. However, there is limited information on the role of probiotics and/or phytobiotic compounds on the treatment and prevention of Clostridium perfringens infections in broiler chicks. This study aimed to assess the effects of probiotic compounds (Maxus, CloStat, Sangrovit Extra, CloStat + Sangrovit Extra and Gallipro Tech) on the growth performance, blood biochemistry and intestinal health of broiler chicks in vivo. The results demonstrated that the inclusion of probiotic and/or phytobiotic compounds has a positive effect on performance, blood constituents, liver histopathology, intestinal morphology and histopathology. Furthermore, a notable reduction in both lesion scores was observed when probiotics and phytobiotics alone or in combination were included in the diets.

Abstract

This study evaluated the effects of feed additives on the growth, blood biochemistry and intestinal health of broiler chicks. A total of 378 of broiler chicks (Ross 308) were randomly allotted to seven groups. Chicks were fed a basal diet with 0.0 (control negative), 0.0 (control positive), 0.1, 0.5, 0.12, 0.5 + 0.12 and 0.2 g Kg⁻¹ of Maxus, CloStat, Sangrovit Extra, CloStat + Sangrovit Extra and Gallipro Tech, respectively for 35 days. After 15 days, the chicks were inoculated with Clostridium perfringens. All feed additives were found to enhance growth performance and feed efficiency. The best feed conversion ratio was found in the Negative Control, CloStat + Sangrovit Extra and Gallipro Tect groups, respectively. A notable increase in villus length, total villus area, small intestine weight, ilium weight and total lesion score was found in chicks supplemented with Bacillus subtilis. Besides, the dietary inclusion of phytobiotic compounds showed potential in reducing the serum Alanine aminotransferase (ALT) concentration and increasing the glucose levels. All intestine and liver histopathological signs were reduced in chicks fed a probiotic-supplemented diet. Our findings indicate that supplementation with probiotics and phytobiotics alone or in combined form can be used to enhance performance, intestine health and blood constituents against C. perfringens infection in broiler chicks.

Effects of Fermented Tea Residue on Fattening Performance, Meat Quality, Digestive Performance, Serum Antioxidant Capacity, and Intestinal Morphology in Fatteners

Simple Summary

Tea residue is the remaining residue of tea after drinking or deep processing. With the annual consumption of tea, a large amount of discarded tea residue is produced. If the tea residue is not effectively utilized, it will cause not only environmental pollution, but also represent a waste of resources. In this study, strains of Bacillus subtilis, Aspergillus niger, and Saccharomyces cerevisiae were used to produce fermented tea residue (FTR). Different levels of FTR were used instead of corn and soybean meal. The resulting product was used to feed pigs bred for rapid growth, also known as fatteners. We explored its effects on growth performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology in fatteners. The aim is to provide a scientific basis for the future use of FTR as a feed material.

Abstract

This study investigated the dietary supplementation of tea residue fermented by Bacillus subtilis, Aspergillus niger, and Saccharomyces cerevisiae, to explore its effects on growth performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology in pigs bred for rapid growth, also known as fatteners. One hundred and ninety-two healthy “Duroc × Landrace × Yorkshire” ternary hybrid pigs (body weight 70 ± 1.0 kg) were randomly divided into four groups according to the feeding test requirements, with four replicates in each group, and 12 fatteners per replicate. The control group (CG) was fed the basal diet. Treatments 1 (T1), 2 (T2), and 3 (T3), comprising ratios of 10%, 15%, and 20% of tea residue were added to the basal diet. The test period was 60 days. The results showed that supplementation of FTR in fatteners’ diets increased final body weight (FBW), average daily gain (ADG), and feed conversion ratio (FCR) in the T1 and T2 groups (p < 0.05). Compared with the other groups, the lightness (L*) and pH were significantly affected in the T2 group (p < 0.05). Compared with the CG, dietary supplementation of FTR significantly increased the nutrient digestibility of crude protein (CP), ether extract (EE), calcium (Ca), and phosphorus (P), improved the lipase and trypsin activities, and reduced drip loss and the shear force of fatteners (p < 0.05). Glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) were significantly increased in the T2 and T3 groups compared with the other groups (p < 0.05). Supplementation of FTR in the jejunum significantly increased the villi height of the T2 group and the ratio of villi height to crypt depth of the FTR groups. Compared with the other two groups, the T2 and T3 groups significantly reduced the ratio of the villous height to crypt depth in the duodenum (p < 0.05). In conclusion, the tea residue after fermentation was shown to have beneficial effects on the fattening performance, digestion performance, meat quality, serum antioxidant capacity, and intestinal morphology of fatteners.

Effects of enzymatic hydrolysate of locust bean gum on digestibility, intestinal morphology and microflora of broilers

To investigate the effects of different levels of enzymatic hydrolysate of dietary locust bean gum on nutrient digestibility, intestinal morphology and microflora of broilers, a total of 768 one-day-old Arbor Acres (AA) broiler chicks were randomly divided into 6 treatments with 8 replicates per treatment and 16 birds per replicate. The treatments were as follows: (1) CON, basal diet; (2) ANT, basal diet +62.5 mg/kg flavomycin; (3) LBG, basal diet +0.1% locust bean gum; (4) ELBG-0.1, basal diet +0.1% enzymatic hydrolysate of LBG; (5) ELBG-0.2, basal diet +0.2% enzymatic hydrolysate of LBG; and (6) ELBG-0.3, basal diet +0.3% enzymatic hydrolysate of LBG. The digestibilities of ether extract, crude protein and dry matter were increased (p < .01) in broilers fed the ELBG-0.3 diet compared with the CON and LBG diets on day 21. Duodenal villus height and the ratio of the villus height to crypt depth were greater (p < .01) in broilers fed the ELBG-0.3 diet than the CON, ANT and LBG diets. Jejunum villus height was higher (p < .05) in broilers fed the ELBG-0.2 and ELBG-0.3 diets than the CON diet. The number of caecal Escherichia coli was reduced (p = .01) in broilers fed the ELBG-0.2 and ELBG-0.3 diets compared with the CON diet. The number of caecal Lactobacilli was greater (p < .05) in broilers fed the ELBG-0.3 diet than the CON and ANT diets. In summary, the addition of 0.3% locust bean enzymatic hydrolysate can increase the surface area of intestinal villi and the number of beneficial bacteria, inhibit the proliferation of harmful bacteria, maintain the balance of intestinal microflora and improve the digestibility of nutrients.

Improvement of growth performance and parameters of intestinal function in liquid fed early weanling pigs1

Liquid feeding, a widely used technique, has been applied as a feeding technique commonly in global swine production. The objective of this study was to evaluate the effects of liquid feeding on growth performance, nutrient digestibility, and intestinal barrier functions during the early weaning period in pigs. Three hundred and sixty 24-d-old weanling pigs (Duroc × Landrace × Yorkshire) with BW of 6.98 ± 0.15 kg were randomly assigned to a control diet (dry fed basal diet, CON) or as meal mixed with water in the ratio 1:4 (liquid fed basal diet, LF) with 6 replicates per treatment and 30 weanling pigs per replicate. The study lasted 7 d. On days 4 to 7, fresh fecal samples were collected to evaluate apparent total tract digestibility (ATTD) of nutrients. After 7 d, 2 weanling pigs per pen were euthanized and physiological samples were obtained. Results showed that LF increased (P < 0.05) ADG (281 g vs. 183 g), ADFI (374 g vs. 245 g), and final BW (8.95 kg vs. 8.26 kg) compared with CON. Compared with CON, LF significantly decreased (P < 0.05) serum cortisol and d-lactate concentrations as well as the activity of diamine oxidase, enhanced (P < 0.05) the ATTD of ether extract and ash, increased (P < 0.05) the activities of amylase, lipase, and lactase in the jejunal mucosa. Furthermore, LF had higher (P < 0.05) villus height and villi height:crypt depth and increased (P < 0.05) mRNA expressions of insulin-like growth factors-1 receptor (IGF-1R), claudin-2 (CLDN-2), zonula occludens-1 (ZO-1), and zonula occludens-2 (ZO-2) in the jejunum. Moreover, LF had lower (P < 0.05) abundances of total bacteria and Escherichia coli and higher (P < 0.05) concentrations of acetic acid and butyric acid in cecal digesta. Altogether, the results indicated that liquid feeding not only promoted growth performance but also improved intestinal health by enhancing gut barrier functions in weanling pigs.

Effects of Supplementation of Branches and Leaves Trimmed from Tea Plant on Growth Performance, Rumen Fermentation and Meat Composition of Nanjiang Yellow Goats

Simple Summary

The effects of supplementation of branches and leaves trimmed from tea tree (BLTT) on growth performance, rumen fermentation characteristics and meat composition of fattening Nanjiang Yellow goats were studied. Supplementation of 4% BLTT increased final body weight of goats and also increased the activity of superoxide dismutase, while glutathione peroxidase and malondialdehyde followed the quadratic curve. Quadratic curves were also observed for villus height, crypt depth and the ratio of villus height to crypt depth in the jejunum. The quadratic effect was obtained for total essential amino acids, and individual amino acids threonine and leucine. Supplementation of 4% BLTT decreased the saturated fatty acid C16:0, and a quadratic effect was observed for polyunsaturated fatty acid C18:3 (n−3). From the present study, it is concluded that BLTT supplementation has a positive effect on body antioxidative status, gastrointestinal development, rumen fermentation characteristics and overall hence growth performance and meat composition in goats.

Abstract

Thirty-two 6-month-old, healthy Nanjiang Yellow goats (34.6 ± 4.16 kg) were randomly divided into four treatments to evaluate the supplementary effects of branches and leaves trimmed from tea tree (BLTT) on growth performance, rumen fermentation characteristics, and meat composition in fattening goats. The control goats were fed a basal diet. Treatments 1, 2 and 3 were fed 2%, 4% and 6% of BLTT respectively. After a 60 d feeding trial, blood samples were collected for the analysis of the antioxidant profile and goats were slaughtered to obtain the rumen fluid and carcass samples for determination of rumen fermentation characteristics and meat composition perameters. Increased final body weight was observed in goats fed 4% BLTT compared with control. The activity of superoxide dismutase was increased in the 4% BLTT-treated group, while glutathione peroxidase and malondialdehyde followed the quadratic curve. Quadratic curves were also observed for villus height, crypt depth and the ratio of villus height to crypt depth in the jejunum. The quadratic effect was obtained for total essential amino acids, and individual amino acids threonine and leucine. The saturated fatty acid C16:0 was decreased with 4% of BLTT supplementation, and a quadratic effect was observed for polyunsaturated fatty acid C18:3 (n−3). To sum up, our findings revealed that BLTT supplementation has a positive effect on body antioxidative status, gastrointestinal development, rumen fermentation characteristics and overall growth performance and meat quality in goats.

Effects of maternal protein supplementation and inclusion of rumen-protected fat in the finishing diet on nutrient digestibility and expression of intestinal genes in Nellore steers

The study aimed to evaluate nutrient digestibility and intestine gene expression in the progeny from cows supplemented during gestation and fed diets with or without rumen-protected fat (RPF) in the feedlot. Forty-eight Nellore steers, averaging 340 kg, were housed in individual pens and allotted in a completely randomized design using a 2 × 2 factorial arrangement (dams nutrition × RPF). Cows' supplementation started after 124 ± 21 days of gestation. The feedlot lasted 135 days and diets had the inclusion of zero or 6% of RPF. Digestibility was evaluated by total feces collection. Steers were slaughtered using the concussion technique and samples of pancreas and small intestine were collected immediately after the slaughter to analyze α-amylase activity, and the expression of SLC5A1, CD36, and CCK and villi morphometry. Feeding RPF increased nutrients digestibility (p < 0.01). There was no effect of maternal nutrition on digestibility and α-amylase activity in steers (p > 0.05). Duodenal expression of SLC5A1, CD36, and CCK increased in the progeny from restricted cows. In conclusion, protein restriction during mid to late gestation of dams has long-term effects on small-intestine length and on expression of membrane transporters genes in the duodenum of the progeny. However, maternal nutrition does not affect digestibility in the feedlot.

Effects of a Lactulose-Rich Diet on Fecal Microbiome and Metabolome in Pregnant Mice

Lactulose, a safe and beneficial molecule, can be used in food as a prebiotic and as an osmotic laxative during pregnancy. This work evaluated the effects of dietary lactulose on the gut microenvironment of pregnant mice using the fecal microbiota and metabolomic profiling. After 2 weeks of feeding, the Bifidobacterium and Bacteroides abundances in the mouse feces were significantly increased in the LAC-high (the diet supplemented with 15% lactulose) group. A total of 15 metabolites, including 1-monoolein, glucose-6-phosphate, and short-chain fatty acids, were increased significantly in the LAC-high group. The serum glucose and total cholesterol concentrations were significantly decreased, while the progesterone level was significantly increased in the lactulose-fed mice. In the LAC-high group, the colonic pH and intestinal permeability were decreased, while the immunoglobulins in the colonic epithelial cells and the small intestinal absorption capacity were significantly increased. These findings indicated that lactulose supplementation benefitted pregnancy performance in mice.

Dietary Branched-Chain Amino Acids Regulate Food Intake Partly through Intestinal and Hypothalamic Amino Acid Receptors in Piglets

Strategies to increase feed intake are of great importance for producing more meat in swine production. Intestinal and hypothalamic amino acid receptors are found to largely participate in feed intake regulation. The purpose of the current research is to study the function of branched-chain amino acid (BCAA) supplementation in the regulation of feed intake through sensors that can detect amino acids in piglets. Twenty-four piglets were assigned one of four treatments and fed one of the experimental diets for either a short period (Expt. 1) or a long period (Expt. 2): a normal protein diet (NP, 20.04% CP), a reduced-protein diet (RP, 17.05% CP), or a reduced-protein test diet supplemented with one of two doses of BCAAs (BCAA1, supplemented with 0.13% l-isoleucine, 0.09% l-leucine, and 0.23% l-valine; BCAA2, supplemented with the 150% standardized ileal digestibility BCAA requirement, as recommended by the National Research Council (2012)). In Expt. 1, no differences were observed in the feed intake among piglets fed different diets ( P > 0.05). In Expt. 2, compared with the RP group, the feed intake of piglets was significantly increased after sufficient BCAAs were supplemented in the BCAA1 group, which was associated with decreased cholecystokinin secretion ( P < 0.05), down-regulated expression of type-1 taste receptors 1/3 (T1R1/T1R3) in the intestine, as well as increased expression of pro-opiomelanocortin, activated general control nonderepressible 2 (GCN2), and eukaryotic initiation factor 2α (eIF2α) in the hypothalamus ( P < 0.05). However, the feed intake was decreased for unknown reasons when the piglets were fed a BCAA over-supplemented diet. Our study confirmed that a BCAA-deficient diet inhibited feed intake through two potential ways: regulating the amino acid T1R1/T1R3 receptor in the intestine or activating GCN2/eIF2α pathways in the hypothalamus.

Reduced dietary nitrogen with a high Lys:CP ratio restricted dietary N excretion without negatively affecting weaned piglets

We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen (N) pollution associated with animal husbandry. Two experiments (45 d each experiment) were performed on weaned piglets (Duroc × Landrace × Yorkshire, 28 d of age) to test this and to determine the optimal lysine to crude protein (Lys:CP) ratio in diet. In Exp. 1, 12 piglets (6 replicates [n = 6]) were fed diets containing different levels of CP (17% and 20%) but the same level of Lys. Increased CP content resulted in significant increases (P < 0.05) of average daily gain (ADG), average daily feed intake (ADFI), and body weight (BW), but did not affect the feed to gain ratio. In Exp. 2, 24 piglets (8 replicates [n = 8]) were fed 1 of 3 diets as follows: 1) 20% CP with a regular Lys:CP ratio (6.23%, control); 2) 17% CP with a reduced Lys:CP ratio (6.14%, LL); or 3) 17% CP with a standard Lys:CP ratio (7.32%, SL). The ADG, final BW, serum concentrations of growth hormone and insulin-like growth factor-1, villus height in the jejunum, and villus height to crypt depth ratio were the lowest in piglets fed LL diet, whereas blood urea N concentration was the lowest and the value of lipase activity was the highest in the piglets fed SL diet. The SL diet did not affect growth performance, intestinal morphology, or serum hormone concentrations, indicating that reduced dietary N with a high Lys:CP ratio can efficiently reduce dietary N excretion without negatively affecting weaned piglets.

Role of Feed Processing on Gut Health and Function in Pigs and Poultry: Conundrum of Optimal Particle Size and Hydrothermal Regimens

The aim is to give an overview of available literature data on the role of feed processing on gut health and function with specific focus on particle size and hydrothermal processing. In addition, influence of feed processing on efficacy of exogenous feed enzymes will be discussed. The current feed processing technologies are such that ingredient choices and diet form are refined to improve feed intake and nutrient utilization efficiency. Finer feed particle size enables optimal nutrient utilization and enhances animal performance due to increased surface area allowing better contact with digestive enzymes. Moreover, adequate diminution of feed ingredients is beneficial to feed manufacturing processes such as mixing and hydrothermal treatments including pelleting, extrusion, and expansion. However, emerging trends in consumer and regulatory demands for restriction or cessation of animal production practices such as use of antimicrobial growth promoters are challenging current approaches to feed processing. There is limit as to the fineness of the particle size, as very fine particles negatively affect gut health due to higher incidences of stomach ulceration in pigs and gizzard dysfunction in poultry. Coarse particle size increases stomach and hindgut acidification which may be beneficial in controlling proliferation of enteric pathogens such as salmonella and E. coli. Optimal particle size could be designed in the grinding process using roller or hammer mill. However, since most commercial pigs and poultry diets are subjected to hydrothermal processes, additional reduction of feed particle size is inevitable. The need to achieve high physical quality and to reduce potential levels of feed-borne pathogens such as Salmonella has led to the application of relatively high conditioning temperatures during conventional hydrothermal processes, a practice that does not favor high nutrient utilization and stability of heat sensitive feed additives such as feed enzymes. Therefore, with evolving pig and poultry production practices, the regimens for feed processing will no longer be appreciated only in terms of optimizing nutrients utilization, but also in terms of impact on feed hygienic status, efficacy of feed additives, animal health, and food safety.

Partially defatted black soldier fly larva meal inclusion in piglet diets: effects on the growth performance, nutrient digestibility, blood profile, gut morphology and histological features

Background

The aim of this trial was to investigate the effects of different inclusion levels of a partially defatted black soldier fly (BSF, Hermetia illucens L.) larva meal on the growth performance, nutrient digestibility, blood profile, gut morphology and histological features of piglets. A total of 48 newly weaned piglets were individually weighed (initial body weight (IBW): 6.1 ± 0.16 kg) and randomly allocated to 3 dietary treatments (4 boxes as replicates/treatment and 4 animals/box). BSF larva meal was included at increasing levels (0% [BSF0], 5% [BSF5] and 10% [BSF10]) in isonitrogenous and isoenergetic diets formulated for two feeding phases: I (from d 1 to d 23) and II (from d 24 to d 61). The weight gain (WG), average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated for each feeding phase and for the whole trial. The haematochemical parameters and nutrient digestibility of the piglets were also evaluated. A total of 3 piglets per box were slaughtered on d 61 and the slaughtered piglets were submitted to morphometric investigations and histopathological examinations.

Results

No overall significant differences were observed for growth performance (P > 0.05), except for the ADFI of phase II, which showed a linear response to increasing BSF meal levels (P < 0.05, maximum for the BSF10 group). Dietary BSF meal inclusion did not significantly influence the blood profile, except as far as monocytes and neutrophils are concerned, and these showed a linear and quadratic response, respectively, to increasing BSF meal levels (P < 0.05, maximum for the BSF10 and BSF5 groups, respectively). On the other hand, the nutrient digestibility, gut morphology and histological features were not affected by dietary BSF meal inclusion (P > 0.05).

Conclusions

The obtained results show that a partially defatted BSF larva meal can be used as a feed ingredient in diets for weaned piglets without negatively affecting their growth performance, nutrient digestibility, blood profile, gut morphology or histological features.

Effects of L-lysine·H2SO4 product on the intestinal morphology and liver pathology using broiler model

Background

Lysine is used widely in livestock production due to the shortage of feed protein resources. L-lysine·H₂SO₄ contains L-lysine sulphate as well as fermentation co-products which contain other amino acids and phosphorus. However, there are few articles about L-lysine·H₂SO₄ product regarding intestinal morphology and liver pathology of broiler chickens. In this article, we focus on the absorption and metabolism of L-lysine·H₂SO₄ revealed in the variation of intestinal morphology and liver pathology to determine the tolerance of chicks for L-lysine·H₂SO₄.

Methods

To evaluate the tolerance of broilers for L-lysine·H₂SO₄, 240 one day old broilers were allocated randomly to one of five dietary treatments which included corn-soybean diets containing 0, 1%, 4%, 7% or 10% L-lysine·H₂SO₄ (L-lysine content = 55%).

Results

Supplementation of 1% L-lysine·H₂SO₄ in the diet had no negative effects. However, 4%, 7% or 10% L-lysine·H₂SO₄ supplementation produced negative responses on broiler performance, carcass characteristics, blood biochemistry, and particularly on intestinal morphology and liver pathology compared with broilers fed the control diet.

Conclusion

Our results show that supplementation with 1% L-lysine·H₂SO₄ had no negative effects on performance, carcass characteristics, blood biochemistry, intestinal morphology and liver pathology in broilers, but supplementation with 4%, 7% or 10% L-lysine·H₂SO₄ produced a negative response, particularly with respect to intestinal morphology and liver pathology.

Dietary chlorogenic acid supplementation affects gut morphology, antioxidant capacity and intestinal selected bacterial populations in weaned piglets

Chlorogenic acid (CGA), an ester formed between caffeic acid and quinic acid, is one of the most abundant phenolic acids and is widespread in fruits, vegetables, cereals and tuber crops. Therefore, the present study was conducted to test the hypothesis that dietary supplementation with CGA could improve intestinal health and regulate intestinal selected microbiota in weaned piglets. A total of twenty-four piglets (21 d of age) were randomly assigned to one of four groups according to their initial BW and sex and fed a basal diet (control group) or a basal diet containing 250, 500 and 1000 mg kg-1 CGA, respectively. The whole trial lasted for 28 d. Dietary CGA supplementation increased (P < 0.05) the duodenal villous height and villous height : crypt depth ratio, but decreased (P < 0.05) the F/G ratio and duodenal crypt depth when compared with the control group. Meanwhile, an increase (P < 0.05) in the jejunal villous height and in the ileal villous height : crypt depth ratio were also observed in CGA-fed piglets. Supplementation with CGA significantly increased (P < 0.05) the activity of serum GSH-Px and the activities of duodenal GSH-Px and CAT, upregulated (P < 0.05) the expression of OCLN in the duodenum and jejunum, and decreased (P < 0.05) the ileal MDA content when compared to the control group. In addition, an increase (P < 0.05) in the population of Lactobacillus and a decrease (P < 0.05) in the population of Escherichia coli were observed in the colon of pigs fed CGA diets. Furthermore, pigs fed CGA diets had higher (P < 0.05) propionic and butyric acid concentrations in the colon. Altogether, our results provide evidence that dietary CGA is beneficial for preserving intestinal morphological integrity and selectively regulating intestinal microbiota, which can provide a means to improve gut health and growth performance post-weaning.

Comparative efficacy of antibiotic growth promoter and benzoic acid on growth performance, nutrient utilization, and indices of gut health in nursery pigs fed corn–soybean meal diet

Benzoic acid (BA) supplement was evaluated as an alternative to antimicrobial growth promoter (AGP). Ninety-six piglets (21-d-old at weaning) were placed in pens (four piglets pen−1) based on body weight (BW) and allocated (n = 8) to either control corn–soybean meal diet or control + in-feed antibiotic (AGP, 220 mg chlortetracycline hydrochloride and 31.2 mg tiamulin kg−1) or control + 0.5% BA. Feed intake and BW were measured weekly. Fecal scores for incidence of diarrhea and fecal samples for apparent total tract digestibility (ATTD) of components were taken in week 2. One pig per pen was euthanized on day 14 for jejunal histomorphology and digesta for pH and short-chain fatty acids concentration. In weeks 1–6, pigs fed AGP and BA had better (P < 0.01) gain to feed ratio compared with control fed pigs. On day 12, pigs fed AGP and BA showed lower (P = 0.01) fecal score than control fed pigs. Pigs fed BA had (P < 0.05) higher ATTD of crude protein and taller villi compared with the control or AGP fed pigs. Pigs fed AGP showed higher (P = 0.05) lactic acid concentrations than pigs fed BA, however, none differed (P > 0.05) with control pigs. In conclusion, BA supported piglet growth performance to the same extent as AGP.

Supplemental Bacillus subtilis DSM 32315 manipulates intestinal structure and microbial composition in broiler chickens

Knowledge about the modulation of gut microbiota improves our understanding of the underlying mechanism by which probiotic treatment benefits the chickens. This study examined the effects of Bacillus subtilis DSM 32315 on intestinal structure and microbial composition in broilers. Broiler chicks were fed basal diets without or with B. subtilis supplementation (1.0 × 10⁹ spores/kg of diet). Supplemental B. subtilis increased average body weight and average daily gain, as well as elevated villus height and villus height to crypt depth ratio of ileum in broilers. Multi-dimension analysis showed a certain degree of separation between the cecal microbiota from treatment and control groups. Increased Firmicutes abundance and reduced Bacteroidetes abundance in cecum were observed responded to B. subtilis addition, which also increased the abundances of Christensenellaceae and Caulobacteraceae, and simultaneously decreased the abundances of potentially harmful bacteria such as Vampirovibrio, Escherichia/Shigella and Parabacteroides. Network analysis signified that B. subtilis addition improved the interaction pattern within cecal microbiota of broilers, however, it exerted little influence on the metabolic pathways of cecal microbiota by comparison of the functional prediction of metagenomes. In conclusion, supplemental B. subtilis DSM 32315 improved growth performance and intestinal structure of broilers, which could be at least partially responsible by the manipulation of cecal microbial composition.

Beneficial effects of water-soluble chestnut (Castanea sativa Mill.) tannin extract on chicken small intestinal epithelial cell culture

Feed and water supplementation with powdered hydrolyzable tannins from chestnut represents a valuable alternative strategy to antibiotics in animal nutrition. In this study, we evaluated the effects and safety of a water-soluble form of chestnut tannin (WST) in an in vitro model of chicken small intestinal epithelial cells (CSIEC). A chicken cell culture was established, and WST in concentrations of 0.025, 0.05, 0.1, and 0.2% were tested for cytotoxicity, cell proliferation, metabolic activity, production of reactive oxygen species, intracellular antioxidative potential, genotoxicity, and influence on the epithelia cell cycle. The tested concentrations showed a significant (P < 0.05) greater proliferative effect on CSIEC than the control medium (maximal proliferation at 0.1% WST as determined by optical density measurements). The 0.2% concentration of WST was cytotoxic, causing significantly higher (P < 0.05) nitric oxide and hydrogen peroxide production but with no short-term genotoxicity. Although increasing the concentration caused a decline in the metabolism of challenged cells (the lowest at 0.1% WST), metabolic activity remained higher than that in control cells. The antioxidant potential was 75% better and significantly (P < 0.05) higher in the 0.1% WST cultured cells compared to control. In conclusion, the cultured CSIEC are useful tools in basic and clinical research for the study of intestinal physiology, as they retain physiological and biochemical properties and epithelial morphology close to the original tissue and, in many ways, reflect the in vivo state. Our results indicate that WST exert a beneficial effect on intestinal epithelia, since they: i) stimulate proliferation of enterocytes; ii) increase antioxidative potential; iii) have no genotoxic effect; and iv) do not affect cellular metabolism. Our results reinforce the importance of WST as promising candidates for further evaluation and use in commercial broiler farm production.

Re-thinking the chicken-Campylobacter jejuni interaction: a review

Chickens are recognized as an imperative source of thermophilic Campylobacter spp., carrying this microorganism in high numbers in their intestinal tract. For a long time, Campylobacter jejuni has been considered as a commensal microorganism which colonizes its primary host rather than infecting it, in the absence of any obvious clinical signs. However, recent studies question this and argue for a deeper understanding of the host-bacteria interaction. Following oral uptake, it was demonstrated that C. jejuni interacts intimately with the gut epithelium and influences cellular functions of the host, with consequences on nutrient absorption. The immune reaction of the host which was revealed in some studies confirmed the infectious nature of C. jejuni. In agreement with this, an increased expression of pro-inflammatory cytokine genes was noticed. The ability to induce intestinal damage and to modulate the barrier function of the intestinal epithelia has further consequences on gut integrity, as it facilitates the paracellular passage of C. jejuni into the underlying tissues and it supports the translocation of luminal bacteria such as Escherichia coli to internal organs. This is associated with an alteration of the gut microbiota as infected birds have a significantly lower abundance of E. coli in different parts of the intestine. Some studies found that the gut microbiota influences the infection and translocation of C. jejuni in chickens in various ways. The effects of C. jejuni on the intestinal function of chickens already indicate a possible interference with bird performance and welfare, which was confirmed in some experimental studies. Furthermore, it could be demonstrated that a Campylobacter infection has an influence on the movement pattern of broiler flocks, supporting experimental studies. The intense interaction of C. jejuni with the chicken supports its role as an infectious agent instead of simply colonizing the gut. Most of the findings about the impact of Campylobacter on chickens are derived from studies using different Campylobacter isolates, a specific type of bird and varying experimental design. However, experimental studies demonstrate an influence of the aforementioned parameters on the outcome of a certain trial, arguing for improved standardization. This review summarizes the actual knowledge of the host-pathogen interaction of C. jejuni in chickens, emphasizing that there are still major gaps despite recently gained knowledge. Resolving the cascade from oral uptake to dissemination in the organism is crucial to fully elucidating the interaction of C. jejuni with the chicken host and to assess the clinical and economic implications with possible consequences on preventive interventions.

In ovo feeding of l-arginine regulates intestinal barrier functions of posthatch broilers by activating the mTOR signaling pathway

BACKGROUND

During the last phase of incubation, dramatic physiological and metabolic changes occur in chick embryos, and supplies of nutrients and energy are always insufficient. This study investigated the effects of in ovo feeding (IOF) of l-arginine (Arg) on the hatchability, growth performance, intestinal development and functions of posthatch broilers.

RESULTS

The IOF of Arg increased (P < 0.05) the feed intake and body weight gain during 1-21 days and 1-42 days, and the intestinal weight of 7- and 21-day-old broilers, compared with non-injected control and diluent-injected groups. The IOF of Arg increased (P < 0.05) villus height (VH), ratio of VH to crypt depth (CD) and density of goblet cells, and decreased (P < 0.05) the CD in jejunum of 1-, 7- and 21-day-old broilers. The IOF of Arg also increased (P < 0.05) the percentage of proliferating cell nuclear antigen positive cells of villus, and the mRNA expressions of mucin-2, claudin-1, zonula occludens-1 and -2 in jejunal mucosa of 21-day-old broilers. Meanwhile, IOF of Arg increased (P < 0.05) the protein abundance of phosphorylated mechanistic target of rapamycin (mTOR), ribosomal protein S6 kinase 1 and eukaryotic initiation factor 4E binding protein 1 in jejunal mucosa.

CONCLUSION

The IOF of Arg improved the development and barrier functions of small intestine, which might be associated with activating the mTOR pathway. In addition, the improved intestinal development might explain the improvement in feed intake and consequently the growth performance of broilers. Therefore, IOF of Arg solution could be an effective technology for regulating early nutrition supply and subsequent growth development in the poultry industry. © 2017 Society of Chemical Industry.

Influence of Graded Levels of l-Theanine Dietary Supplementation on Growth Performance, Carcass Traits, Meat Quality, Organs Histomorphometry, Blood Chemistry and Immune Response of Broiler Chickens

l-theanine is a water-soluble non-proteinous amino acid mainly found in green tea leaves. Despite the availability of abundant literature on green tea, studies on the use of l-theanine as a feed additive in animals, and especially broilers are limited. The objective of this study was, therefore, to evaluate the effect of different dietary levels of l-theanine on meat quality, growth performance, immune response, and blood metabolites in broilers. A total of 400 day-old broiler chicks were randomly divided into four treatment groups using a completely randomized design; C-control, basal diet; 100LT-basal diet + 100 mg l-theanine/kg diet; 200LT-basal diet + 200 mg l-theanine/kg diet; and 300LT-basal diet + 300 mg l-theanine/kg diet. Results revealed that the intermediate level of l-theanine (200 mg/kg diet) showed better results in terms of body weight gain (BWG), feed consumed (FC), and feed conversion ratio (FCR) as compared with the other supplemented groups and the control. The live weight eviscerated weight and gizzard weight were higher in all l-theanine levels as compared to those of the control group. Increased weight (p ≤ 0.05) of spleen and bursa were found in group 200LT (200 mg l-theanine/kg diet). Concerning meat color parameters, values for yellowness (b*), and redness (a*) were greater in l-theanine-supplemented groups than the control. Supplementing broiler diet with l-theanine reduced (p = 0.02) total serum cholesterol contents while increased HDL. Further analysis revealed lower relative serum cytokines (IL-2 and INF-γ) and reduced mRNA expression of TNF-α and IL-6 in thymus, and IFN-γ and IL-2 in spleen in the treated group. Moreover, supplementation with 200 mg/kg of l-theanine improved antioxidant status in blood by increasing SOD, GSH-Px, and relative CAT levels. It is concluded that the optimum supplementation level of l-theanine is 200 mg/kg of diet because it resulted in improved performance parameters in broilers. However, higher levels of l-theanine (300 mg/kg diet) may have deleterious effects on performance and health of broiler chickens.

Effect of titanium dioxide nanoparticles on glucose homeostasis after oral administration

As food additives, titanium dioxide nanoparticles (TiO₂ NPs) have been widely used in various products that are usually simultaneously consumed with a high content of sugar, thus necessitating research on the effect of TiO₂ NPs on glucose homeostasis. We conducted an animal study to explore the effect of orally administrated TiO₂ NPs on glucose absorption and metabolism in rats at 0, 2, 10 and 50 mg kg^-1 body weight day^-1 for 30 and 90 days. The results showed that oral exposure to TiO₂ NPs caused a slight and temporary hypoglycemic effect in rats at 30 days post-exposure but recovered at 90 days post-exposure. Decreased levels of intestinal glucose absorption and increased levels of hepatic glucose metabolism may be responsible for the hypoglycemic effect. Remodeling of the villi in the small intestine that decreased the surface area available for glucose absorption and increased levels of hepatic glucose uptake, utilization and storage related to hepatocellular injury are supposed to be the mechanisms. Our results demonstrated that dietary intake of TiO₂ NPs as food additives could affect the absorption and metabolism of glucose.

Dietary supplementation with a nucleotide-rich yeast extract modulates gut immune response and microflora in weaned pigs in response to a sanitary challenge

An experiment was carried out to evaluate the short-term effect of supplementing a nucleotide-rich yeast extract (NRYE) on growth performance, gut structure, immunity and microflora of piglets raised under sanitary and unsanitary conditions. A total of 84, 21-day old piglets were used in this study; 42 piglets were raised in a room designated as the clean room that was washed once per week, whereas the other 42 piglets were raised in a room designated as the unclean room in which 7 kg of manure from the sow herd was spread on each pen floor on day 1 and 7 and the room was not washed throughout the experiment. The pigs were fed a corn-soybean meal-based diet without or with 0.1% NRYE. Each treatment had 7 replicate pens in each room, and each pen housed 3 pigs. Feed disappearance and BW were recorded on day 1 and 14. On day 14, one pig per pen was euthanized to collect ileum, mesenteric lymph nodes and spleen tissues, and cecum and colon digesta. Overall, NRYE supplementation did not affect growth performance in both clean and unclean conditions, improved kidney weight in both clean (P=0.0002) and unclean room (P<0.0001) and tended to improve the villus height/crypt depth ratio in the clean room (P=0.073). Supplementing NRYE was associated with upregulation of Ileal programmed cell death gene-1 (P=0.0003), interleukin (IL)-1β (P<0.0001), IL-6 (P=0.0003), IL-10 (P<0.0001) and tumor necrosis factor-α (TNF-α) (P<0.0001) in pigs raised in the unclean room. Supplementing the NRYE in pigs raised in the clean room suppressed growth of cecal Enterobacteriacea (P<0.0001) members and colonic Enterococcus spp. (P<0.019), improved proliferation of cecal Lactobacillus spp. (P<0.002) and colonic Clostridium cluster IV (P<0.011) and XVIa members (P<0.0002). Supplementing the NRYE in the unclean room improved proliferation of cecal Clostridium cluster IV (P<0.026) and suppressed proliferation of colonic Enterococcus spp. (P<0.037). In conclusion, supplementing the NRYE to piglets under unsanitary conditions improved ileal immune response by upregulating inflammatory cytokines, and positively modulated proliferation of beneficial gut bacteria and suppression of harmful ones in both clean and unclean rooms.

The impact of synbiotic administration through in ovo technology on the microstructure of a broiler chicken small intestine tissue on the 1st and 42nd day of rearing

Background

Application the innovative method which is in ovo technology provides a means of modulating the immune system at early embryonic stages. The aim of study was to determine influence of the in ovo stimulation, on d 12 of incubation, with synbiotics (synbiotic 1- L. salivarius IBB3154 + Bi²tos, Clasado Ltd. and the synbiotic 2 - L. plantarum IBB3036 + lupin RFOs) on the microstructure of duodenum, jejunum and ileum in the 1^st and 42^nd day of rearing.

Results

On the 1^st day of chickens life, in the duodenum of both experimental groups (SYN1 and SYN2), a significantly higher and wider intestinal villi as well as a significantly larger absorbent surface of these villi were found in comparison with the Control group (P ≤ 0.01). On the 42^nd day of rearing the beneficial effect of synbiotic 1 was reflected by the numerically higher villi (no statistical differences) with a larger surface (P ≤ 0.01) in the duodenum in the SYN1 group compare to the Control group. In the jejunum on the 1^st day of life, in the SYN1 group, significantly higher villi than in the Control group, with a simultaneous decrease in the depth of crypts (P ≤ 0.01), and also the largest width of villi and their absorbent area (P ≤ 0.01) in comparison to the other groups were found. On the 42^nd day of life, in the jejunum, an increase in the height of the villi whilst reducing the crypt depth in the SYN2 group was found (P ≤ 0.01). In turn, in the SYN1 group, there were significantly more neutral goblet cells observed compared with the control group (P ≤ 0.05). In the ileum of 1-day-old chickens, the widest villi (P ≤ 0.05) and the deepest crypts (P ≤ 0.01) were found in the SYN2 group. In the same group, there was also the least amount of neutral goblet cells in comparison to the other groups (P ≤ 0.05).

Conclusions

We observed that synbiotic 1 and 2 beneficially affected the examined characteristics on the 1^st and 42^nd day of life. The obtained results allow us to conclude that the use of synbiotics significantly affect gut structure which should contribute to improvement in nutrient absorption by the gut.

Increases in circulating amino acids with in-feed antibiotics correlated with gene expression of intestinal amino acid transporters in piglets

In-feed antibiotics have been commonly used to promote the growth performance of piglets. The antibiotics can increase protein utilization, but the underlying mechanism is largely unknown. The present study investigated the effects of in-feed antibiotics on intestinal AA transporters and receptors to test the hypothesis that the alteration of circulating AA profiles may be concomitant with the change of intestinal AA transporters and receptors. Sixteen litters of piglets at day 7 started to receive creep feed with (Antibiotic) or without (Control) antibiotic. Piglets were weaned at day 23 after birth, and fed the same diets until day 42. In-feed antibiotics did not affect the BW of 23-day-old (P = 0.248), or 42-day-old piglets (P = 0.089), but increased the weight gain to feed ratio from day 23 to 42 (P = 0.020). At day 42 after birth, antibiotic treatment increased the concentrations of most AAs in serum (P < 0.05), and decreased the concentrations of most AAs in jejunal and ileal digesta. Antibiotics upregulated (P < 0.05) the mRNA expression levels for jejunal AAs transporters (CAT1, EAAC1, ASCT2, y⁺LAT1), peptide transporters (PepT1), and Na⁺-K⁺-ATPase (ATP1A1), and ileal AA transporters (ASCT2, y⁺LAT1, b^0,+AT, and B⁰AT1), and ATP1A1. The antibiotics also upregulated the mRNA expression of jejunal AAs receptors T1R3 and CaSR, and ileal T1R3. Protein expression levels for jejunal AA transporters (EAAC1, b^0,+AT, and ASCT2) and PepT1 were also upregulated. Correlation analysis revealed that the alterations of AA profiles in serum after the in-feed antibiotics were correlated with the upregulations of mRNA expression levels for key AA transporters and receptors in the small intestine. In conclusion, the in-feed antibiotics increased serum level of most AAs and decreased most AAs in the small intestine. These changes correlated with the upregulations of mRNA expression levels for key AA transporters and receptors in the small intestine. The findings provide further insights into the mechanism of in-feed antibiotics, which may provide new framework for designing alternatives to antibiotics in animal feed in the future.

Effects of dietary valine:lysine ratio on the performance, amino acid composition of tissues and mRNA expression of genes involved in branched-chain amino acid metabolism of weaned piglets

Objective

The goal of this study was to investigate the effects of dietary standard ileal digestible (SID) valine:lysine ratios on performance, intestinal morphology, amino acids of liver and muscle, plasma indices and mRNA expression of branched-chain amino acid (BCAA) metabolism enzymes.

Methods

A total of 144 crossbred pigs (Duroc×Landrace×Large White) weaned at 28±4 days of age (8.79±0.02 kg body weight) were randomly allotted to 1 of 4 diets formulated to provide SID valine:lysine ratios of 50%, 60%, 70%, or 80%. Each diet was fed to 6 pens of pigs with 6 pigs per pen (3 gilts and 3 barrows) for 28 days.

Results

Average daily gain increased quadratically (p<0.05), the villous height of the duodenum, jejunum and ileum increased linearly (p<0.05) as the SID valine:lysine ratio increased. The concentrations of plasma α-keto isovaleric and valine increased linearly (p<0.05), plasma aspartate, asparagine and cysteine decreased (p<0.05) as the SID valine:lysine ratio increased. An increase in SID lysine:valine levels increased mRNA expression levels of mitochondrial BCAA transaminase and branched-chain α-keto acid dehydrogenase in the longissimus dorsi muscle (p<0.05).

Conclusion

Using a quadratic model, a SID valine:lysine ratio of 68% was shown to maximize the growth of weaned pigs which is slightly higher than the level recommended by the National Research Council [6].

The Effects of Agave fourcroydes Powder as a Dietary Supplement on Growth Performance, Gut Morphology, Concentration of IgG, and Hematology Parameters in Broiler Rabbits

This study was conducted to determine the effects of Agave fourcroydes powder as a dietary supplement on the growth performance, gut morphology, serum concentration of IgG, and the hematology parameters of broiler rabbits. A total of 32 rabbits [New Zealand × Californian] were weaned at 35 days. They were randomly selected for two dietary treatments (eight repetitions per treatment), which consisted of a basal diet and a basal diet supplemented with 1.5% dried-stem powder of A. fourcroydes. On day 60 from the initiation of treatment, gut histomorphology (duodenum and cecum), serum concentration of IgG, and hematology parameters were all measured. The results showed that A. fourcroydes powder supplementation improved (P < 0.05) the ADFI, ADG, and final BW. Correspondingly, this treatment increased (P < 0.05) the muscle and mucosa thickness and height and width of villi. However, duodenum crypts depth was lower (P < 0.05) when rabbits were fed with this natural product, compared with the basal diet treatment. Results also indicated that the A. fourcroydes powder increased (P < 0.05) the serum concentration of IgG but did not change the hematology parameters. This data indicates that A. fourcroydes powder, as a supplement, had beneficial effects on increasing the growth performance and serum concentration of IgG, as well as improving the gut morphology without affecting the hematology parameters in broiler rabbits.