This study was conducted to explore the effect of graded levels of pyrroloquinoline quinone disodium (PQQ·Na2) on the performance and intestinal development of weaned pigs. A total of 216 pigs weaned at 28 d were assigned in a randomized complete block design to 6 diets containing 0, 1.5, 3.0, 4.5, 6.0, or 7.5 mg/kg PQQ·Na2 for 28 d. Performance, diarrhea incidence, intestinal morphology, redox status, cytokines, and the expression of tight junction proteins were determined. Pigs had increased ADG (linear, P < 0.01), G:F (quadratic, P < 0.01), and lower diarrhea incidence (P < 0.01) with the increase of PQQ·Na2 supplementation. Villus height increased (quadratic, P < 0.01) in all segments of the small intestine, and crypt depth in the duodenum and jejunum was decreased (linear, P < 0.05) in pigs with the increase of PQQ·Na2 supplementation. Pigs fed PQQ·Na2-supplemented diets had higher (P < 0.05) activities of antioxidant enzymes including total superoxide dismutase in duodenum, jejunum, and ileum; glutathione peroxidase (GSH-Px) in jejunum and ileum; catalase (CAT) in duodenum and ileum; and lower (P < 0.05) malondialdehyde concentrations in the intestinal mucosa of all segments. In the intestinal mucosa, cytokines including interleukin (IL)-1β, IL-2, and interferon-γ were significantly decreased (P < 0.05) in pigs fed PQQ·Na2-supplemented diets. The protein expression of zonula occluden protein-1 (ZO-1) and occludin in the jejunum was significantly increased (P < 0.05) in pigs fed diets containing PQQ·Na2. In conclusion, these results have indicated that dietary PQQ·Na2 supplementation improves growth performance and gut health in weaned pigs. Moreover, pigs fed diet with as low as 1.5-mg/kg PQQ·Na2 have better performance compared with pigs fed no PQQ·Na2-supplemented diet; pigs fed diet with 4.5-mg/kg PQQ·Na2 have highest G:F among treatments during the whole period.
Modulation of the synthesis of endogenous host defense peptides (HDPs) by probiotics represents a novel antimicrobial approach for disease control and prevention, particularly against antibiotic-resistant infections in human and animals. However, the extent of HDP modulation by probiotics is species dependent and strain specific. In the present study, The porcine small intestinal epithelial cell line (IPEC-J2) cells and neonatal piglets were used as in-vitro and in-vivo models to test whether Lactobacillus reuteri I5007 could modulate intestinal HDP expression. Gene expressions of HDPs, toll-like receptors, and fatty acid receptors were determined, as well as colonic short chain fatty acid concentrations and microbiota. Exposure to 108 colony forming units (CFU)/mL of L. reuteri I5007 for 6 h significantly increased the expression of porcine β-Defensin2 (PBD2), pBD3, pBD114, pBD129, and protegrins (PG) 1-5 in IPEC-J2 cells. Similarly, L. reuteri I5007 administration significantly increased the expression of jejunal pBD2 as well as colonic pBD2, pBD3, pBD114, and pBD129 in neonatal piglets (p < 0.05). This was probably associated with the increase in colonic butyric acid concentration and up-regulating expression of Peroxisome Proliferator-Activated Receptor-γ (PPAR-γ) and G Protein-Coupled Receptor 41 (GPR41) (p < 0.05), but not with stimulation of Pattern-Recognition Receptors. Additionally, supplementation with L. reuteri I5007 in the piglets did not affect the colonic microbiota structure. Our findings suggested that L. reuteri I5007 could modulate intestinal HDP expression and improve the gut health of neonatal piglets, probably through the increase in colonic butyric acid concentration and the up-regulation of the downstream molecules of butyric acid, PPAR-γ and GPR41, but not through modifying gut microbiota structure.
The objective of this experiment was to determine the effects of dietary calcium (Ca) levels on growth performance and bone development of growing and finishing pigs. A total of 150 crossbred pigs (37.0 +/- 4.0 kg BW) were randomly assigned to 5 treatment groups: (1) low Ca levels in both grower and finisher phases (LL), (2) low Ca level in grower phase and high Ca level in finisher phase (LH), (3) medium Ca levels in both grower and finisher phases (MM), (4) high Ca level in grower phase and low Ca level in finisher phase (HL), and (5) high Ca levels in both grower and finisher phases (HH). The dietary phosphorus (P) levels were fixed. The animal trial was conducted for 60 days. When the average pen BW reached approximately 60 kg, the pigs were switched to finisher diets. Pig performance was not affected by dietary treatments during either the grower or finisher phases. During the grower phase, the bone mineral density (BMD) and bending moment of the fourth metacarpal and metatarsal bones were lower (P < 0.05) in pigs fed the low Ca diets than in those fed the medium Ca diets. During the finisher phase, P weight, BMD and bending moment of the fourth metacarpal and metatarsal bones were not different for pigs fed the LH and HL diets compared with pigs fed the HH diet. The bending moment of the fourth metacarpal bone and fat-free dry weight of the fourth metatarsal bone were lower (P < 0.05) in pigs fed the LH diet compared with those fed the MM diet. In conclusion, a compensatory effect occurred in bone characteristics at the end of the finisher phase when the high Ca diet was introduced in the finisher phase, following a low-Ca diet during the grower phase. However, pigs fed LH diet did not surpass the level of bone mineralization achieved by pigs fed the MM diet. (C) 2016 Elsevier B.V. All rights reserved.
The objective of this research was to determine the effects of variety and storage duration on the nutrient digestibility and the digestible (DE) and metabolisable (ME) energy content in maize when fed to growing pigs. Four maize varieties (LS1, LS2, LS3 and LS4) were hand-harvested from the same growing area in China in early October of 2012. The samples were sun dried to about 14% moisture content and then stored in the warehouse of the Fengning Pig Experiment Base at China Agricultural University for 0, 3 or 10months. Twenty-four barrows of about 33 kg body weight were used and allotted to a completely randomised block design with four diets and six replicate pigs per diet. Pigs were individually housed in metabolic crates. The four experimental diets were formulated by mixing 96.8% of each variety of maize with 3.2% vitamins and minerals. A 5-day collection period followed a 7-day diet acclimation period. The results indicated that the DE and ME contents of maize and the apparent total tract digestibility (ATTD) of organic matter (OM), dry matter, gross energy (GE), neutral detergent fibre, acid detergent fibre (ADF), crude protein (CP) and ether extract (EE) were significantly (p<0.05) influenced by maize variety and storage duration. With an extension of storage duration from 0 to 10months, the DE and ME of maize and the ATTD of OM, GE, ADF, CP and EE changed in a quadratic manner (p<0.05), and 3months of storage exceeded 0months of storage by 1.84%, 1.43%, 0.31%, 0.32%, 15.37%, 2.11% and 5.02%, respectively. The DE, ME of maize and the ATTD of OM, GE, ADF, CP and EE decreased by 3.67%, 6.00%, 0.97%, 1.40%, 30.54%, 3.92% and 20.93%, respectively, at 10months of storage compared to 3months of storage. No interaction was observed between maize variety and storage duration in DE and ME contents in maize. In conclusion, under the conditions of this study, most of the nutrient digestibility and the DE and ME contents of maize increased from 0 to 3months and decreased from 3 to 10months.
This study determined the effects of chicken egg yolk antibodies (IgY) on immune responses in the intestinal mucosal of mice infected with Salmonella typhimurium. Sixty, 28-day-old mice were divided into 4 groups and treated with streptomycin or sterile water for 2days followed by 1day without treatment. The control group was unchallenged whereas the mice in the other three groups were treated twice with 109CFUmL−1 S. typhimurium. For the next 3days, control mice continued to receive no treatment whereas the mice in the remaining three groups were orally administered with 20mgmL−1 of specific IgY, 20mgmL−1 of nonspecific IgY or PBS. S. typhimurium activated gut-associated lymphoid tissue, increasing the release of IFN-γ and TNF-α in the mucosa and increased the number of activated T-lymphocytes and cytotoxic T-γδ. Specific IgY attenuated the increase in IFN-γ and TNF-α and the decrease in IL-10. S. typhimurium induced mobilization of CD8+ and CD8+ TCRγδ T cells in the epithelium and CD4+ and CD8+ T cells in the lamina propria reflecting an inflammatory process that was attenuated by IgY. These results suggest that specific IgY modulates intestinal mucosal immune responses during a S. typhimurium infection.
Two experiments were conducted to determine the effects of Lactobacillus plantarum B1 on broiler performance, cecal bacteria, and ileal and cecal short chain fatty acids (SCFA). The study also determined whether it was necessary to feed Lactobacillus throughout the entire growth period or if the beneficial effects could be obtained by supplementation during the starter or finisher period only. Experiment 1 was conducted with 72 broilers assigned to 2 treatments (N=6). One treatment was the basal diet (Con), and the other was the basal diet supplemented with 2×10(9) cfu/kg L. plantarum B1 (Wh). In experiment 2, 144 one-day-old broilers were assigned to 4 treatments (N=6) including a basal diet (Con), the basal diet supplemented with 2×10(9) cfu/kgL. plantarum B1 during d one to 21 only (St), the basal diet supplemented with L. plantarum B1 during d 22 to 42 only (Fn), and, finally, the basal diet supplemented with L. plantarum B1 from d one to 42 (Wh). Experiment 1 showed that L. plantarum B1 enhanced broiler average daily gain (ADG) and feed conversion ratio (FCR). In experiment 2, during the starter period, broilers in the Wh and St treatments had higher ADG (P<0.05) than broilers in the Con and Fn, while during the finisher period, broilers in the Wh and Fn had higher ADG (P<0.01) and improved FCR (P<0.01) compared with broilers in the Con and St. On d 42, broilers in the Wh and Fn had decreased E. coli (P<0.05) and increased lactic acid bacteria (P<0.05) in their cecal digesta. L. plantarum B1 also increased (P<0.05) ileal mucosal sIgA as well as ileal and cecal SCFA. However, L. plantarum B1 had no effect on intestinal morphology. In conclusion,L. plantarum B1 plays a positive role in broilers. Supplementation during the finisher period or the entire growth period is superior to supplementation during the starter period only.
The effects of feeding diets based on soybean meal, low phytate hulless barley (Lphybarley) and low phytate pea (Lphypea) with inorganic phosphorus (iP) reduced by 50 or 100% to broiler chickens on performance, P digestibility and bone characteristics were investigated. Two hundred and ten day-old (Ross 308 strain) broiler chicks (5 birds per cage; 6 cages per diet) were randomly allocated to 7 dietary treatments for a 21-day study. Diets were formulated based on soybean meal-normal phytate hulless barley (SBM-normbarley) with added inorganic P (iP) to meet NRC (1994) P requirements (SBM-normbarley100) or with 50% less iP (SBM-normbarley50), soybean meal-Lphybarley-Lphypea with added iP (Lphybarley-Lphypea100) or iP reduced by 50% (Lphybarley-Lphypea50) or 100% (Lphybarley-Lphypea0), and soybean meal-normbarley-normal phytate pea (normpea) with added iP (normbarley-normpea100) or iP reduced by 50% (normbarley-normpea50). Birds fed the Lphybarley-Lphypea0 diet had the lowest (P<0.001) ADG compared with those fed the other diets. Reducing iP by 50% led to a reduction (P<0.05) in ADG for birds fed the SBM-normbarley-and normbarley-normpea-based diets but not in the Lphybarley-Lphypea-based diet. Reducing iP by 50% led to a reduction (P<0.05) in ADFI in birds fed the SBM-normbarley-based diet and normbarley-normpea-based diet compared with those fed adequate iP. Feed conversion ratio was not affected by diet throughout the experimental period (P>0.10). Reducing iP content reduced P retention in the SBM-normbarley-based diet but not in the normbarley-normpea-based diet but tibia ash and length were reduced in birds fed both diets (P<0.05). Reducing dietary iP content linearly increased (P<0.05) P retention and linearly decreased (P<0.05) tibia ash and length in the Lphypea-Lphybarley-based diets. In conclusion, feeding a low phytate hulless barley-low phytate pea based diet with iP reduced by 50% supported similar performance as control and increased P retention, suggesting that utilizing a combination of low phytate ingredients can reduce the need for supplemental iP with significant cost and environmental implication.
Two experiments were conducted, under typical commercial swine production conditions, to determine effects of dietary arginine supplementation during early gestation on the performance of gilts and sows. In Exp. 1, between d 1 and 30 of gestation, 62 Landrace gilts and 113 sows consumed a corn- and soybean meal-based diet supplemented with 1.3% -arginine HCl or 2.2% -alanine. Total numbers of piglets born ( < 0.05) and born alive ( < 0.01) per litter and litter birth weights of piglets born ( < 0.05) and born alive ( < 0.05) were increased in the arginine group compared with the control. In Exp. 2, 155 multiparous Landrace sows received 1.3% -arginine HCl supplementation between d 1 and 14 (T2; = 41), d 15 and 30 (T3; = 40), or d 1 and 30 (T4; = 37), whereas the control group received 2.2% -alanine supplementation between d 1 and 30 (T1; = 37). Blood samples were randomly obtained from 6 sows per group on d 1, 14, and 28 of gestation to determine plasma concentrations of AA and related metabolites. Total numbers of piglets born ( = 0.084) and born alive ( = 0.080) per litter tended to be higher for sows supplemented with arginine between d 1 and 14 of gestation (T2) than for control sows (T1). Concentrations of arginine and nitric oxide metabolites were greater ( < 0.05) in T4 compared with T1 and T3 on d 14 of gestation and were also greater in T4 compared with T1 and T2 on d 28 of gestation. Plasma concentrations of spermidine ( < 0.001) were increased in T3 and T4 compared with T1 and T2 on d 28. These results indicate that dietary arginine supplementation during early gestation improves the reproductive performance of gilts and sows, possibly via nitric oxide and polyamine-dependent mechanisms.
Sublancin is an antimicrobial peptide produced by 168 containing 37 amino acids. The objective of this study was to investigate its inhibitory efficacy against both in vitro and in vivo. In the in vitro study, we determined that sublancin had a minimum inhibitory concentration of 8 μM against , which was much higher than the antibiotic lincomycin (0.281 μM). Scanning electron microscopy showed that sublancin damaged the morphology of . The in vivo study was conducted on broilers for a 28-d period using a completely randomized design. A total of 252 chickens at 1 d of age were randomly assigned to 1 of 6 treatments including an uninfected control; an infected control; 3 infected groups supplemented with sublancin at 2.88, 5.76, or 11.52 mg activity/L of water; and an infected group supplemented with lincomycin at 75 mg activity/L of water (positive control). Necrotic enteritis was induced in the broilers by oral inoculation of on d 15 through 21. Thereafter, the sublancin or lincomycin were administered fresh daily for a period of 7 days. The challenge resulted in a significant decrease in ADG ( < 0.05) and a remarkable deterioration in G:F ( < 0.05) during d 15 to 21 of the experiment. There was a sharp increase of numbers in the cecum ( < 0.05). The addition of sublancin or lincomycin reduced caecal counts ( < 0.05). The counts had a tendency to decrease in the lincomycin treatment ( = 0.051) but were the highest in the sublancin treatment (5.76 mg activity/L of water). A higher villus height to crypt depth ratio in the duodenum and jejunum as well as a higher villus height in the duodenum were observed in broilers treated with sublancin or lincomycin ( < 0.05) compared with infected control broilers. It was observed that sublancin and lincomycin decreased IL-1β, IL-6, and tumor necrosis factor-α levels ( < 0.05) in the ileum compared with the infected control. In conclusion, although sublancin's minimum inhibitory concentration is much higher than lincomycin in vitro, less sublancin is needed to control necrotic enteritis induced by in vivo than lincomycin. These novel findings indicate that sublancin could be used as a potential antimicrobial agent to control necrotic enteritis.
Five ileal cannulated barrows (43.6 +/- 1.3 kg BW) were used in a 5 x 5 Latin square design experiment to determine the apparent (AID) and standardized (SID) heal digestibility of N and amino acids (AA) in low-phytate field pea (LPP), low-phytate barley (LPB) and normalphytate field pea (NPP) and the apparent total tract digestibility (ATTD) of Ca, P and energy in diets containing these ingredients. In addition, the effects of phytase supplementation (500 FTU/kg) to diets containing LPP or NPP were determined. The experimental diets contained 869, 868 or 870 g/kg LPB, LPP and NPP, respectively, as the sole source of N. The phytate P contents were 0.4, 0.7 and 2.0 g/kg for LPB, LPP and NPP, respectively. Limestone was added to all diets meeting the recommended values, while inorganic P was added only in pea-based diets to provide 65% of the available P recommended by NRC (1998) for 20-50 kg pigs. Titanium dioxide (3 g/kg) was used as an indigestible marker. Daily feed allowance was calculated as 40 g/kg BW at the beginning of each period and was offered in two equal meals at 0800 and 1600 h. Each experimental period lasted for 8 d; d 1-4 for adaptation, d 5-6 for urine and fecal collections, and d 7-8 for ileal digesta collection. The ATTD of DM and GE was not different among diets and was not affected by phytase addition. The AlTD of Ca and P was higher (P<0.05) in LPB than in LPP and NPP diets. Supplementing the LPP and NPP diets with phytase increased (P<0.05) the ATTD of Ca and P. The AID of N and all AA except Met were higher (P<0.05) in LPP and NPP than in LPB, but no difference between LPP and NPP were observed. Phytase supplementation increased (P<0.05) the AID for Arg, Ile, Leu, Phe, Pro, Ser, Tyr, and Val. The SID of AA in LPB, LPP, and NPP were 0.734, 0.895 and 0.895 for Lys, 0.732, 0.757 and 0.744 for Met and 0.755, 0.789 and 0.787 for Thr, respectively. Results indicate that both varieties of field pea had greater AID and SID of AA than LPB. Also, the LPP diet had higher ATTD of Ca and P compared with the NPP diet and phytase supplementation improved digestibility of P, Ca and some AA. Crown Copyright (C) 2015 Published by Elsevier B.V. All rights reserved.
This study was conducted to determine whether supplemental conjugated linoleic acid (CLA) fed during late gestation affects reproductive performance, colostrum production and colostral immunoglobulin (Ig) levels of multiparous sows. Forty-eight, pregnant, Landrace x Large White, multiparous sows were allotted to four dietary treatments (n = 12), control (CTR, no CLA addition) and 7.5, 15.0, or 22.5 g/kg CIA supplementation from d 85 of gestation until farrowing. The CIA was added at the expense of soybean oil. All sows were fed the same commercial lactation diet postpartum. Blood samples were collected from sows on d 85, 100 and 112 of gestation while blood samples were obtained from neonatal piglets 24 h postpartum. Colostrum was collected immediately after farrowing and its production was estimated for 24 h starting with the birth of the first piglet. Neither the body weight nor backfat thickness of sows were altered by dietary CIA Reproductive performance, piglet growth and calculated colostrum production were also unaffected. Compared with the CTR diet, dietary CIA supplementation during late gestation decreased (P < 0.01) the colostral fat, and increased (P < 0.01) the concentrations of IgG, IgA, and IgM in colostrum (P < 0.01). The concentrations of serum Ig and interleukin-2 on d 112 of gestation were increased (P < 0.01) in sows receiving CLA, although those factors did not differ among different levels of CIA supplementation. Serum IgG, IgA, and IgM concentrations in piglets from sows fed diets containing CIA were increased (P < 0.05) 24h postpartum. This study indicates that dietary CIA has potential immunomodulatory effects in gestating sows and neonatal piglets, whereas there were no differences within the CIA treatments. (C) 2015 Elsevier B.V. All rights reserved.
Seventy-two, suckling piglets, obtained from 9 litters standardized to 8 piglets, were assigned to 1 of 3 treatments (n = 24) to compare short-term, early administration with intermittent, longer-term administration of Lactobacillus reuteri I5007. The treatments were a control (given a placebo of 0.1% peptone water from day 1 to 5) or treatments in which 1.7 × 1010 CFU L. reuteri was administrated either daily for 4 days starting on day 1 or every 4th day from day 1 to 17. Five piglets per treatment were killed at 3 time points (day 7, 14 and 21). Denaturing Gradient Electrophoresis of ileal digesta revealed an increase in the presence of L. reuteri I5007 and Clostridium lentocellum (on day 14 and 21) in the every 4th-day treatment and Actinobacillus porcinus (on day 7 and 14) in both L. reuteri treatments, while reducing the abundance of E. coli on day 21 in the every 4th-day treatment. Real-time qPCR of ileal digesta showed an increase in Bifidobacterium spp. on day 14 for both L. reuteri I5007 treatments. An increase in the concentration of lactic acid and a lower pH was observed in the first 4-day treatment on day 7 and the every 4th day treatment on day 14. The relative abundance of mRNA for TGF-β was increased while that for IFN-γ was decreased in the mesenteric lymph nodes of piglets treated with L. reuteri every 4th day. In conclusion, early intervention with L. reuteri increases the presence of beneficial bacteria and decreases the presence of undesirable microbes in the lower gastrointestinal tract. The changes appear to be mediated by altering the intestinal pH through lactic acid production resulting in favorable bacterial species colonization. A prolonged duration of treatment (i.e. every 4th day) would appear to be superior to treatment only during the first 4 days.
Four 28-d experiments were conducted to determine the standardized ileal digestible (SID) valine (Val) to lysine (Lys) ratio required for 26- to 46- (Exp. 1), 49- to 70- (Exp. 2), 71- to 92- (Exp. 3), and 94- to 119-kg (Exp. 4) pigs fed low CP diets supplemented with crystalline AA. The first 3 experiments utilized 150 pigs (Duroc × Landrace × Large White), while Exp. 4 utilized 90 finishing pigs. Pigs in all 4 experiments were randomly allocated to 1 of 5 diets with 6 pens per treatment (3 pens of barrows and 3 pens of gilts) and 5 pigs per pen for the first 3 experiments and 3 pigs per pen for Exp. 4. Diets for all experiments were formulated to contain SID Val to Lys ratios of 0.55, 0.60, 0.65, 0.70, or 0.75. In Exp. 1 (26 to 46 kg), ADG increased (linear, = 0.039; quadratic, = 0.042) with an increasing dietary Val:Lys ratio. The SID Val:Lys ratio to maximize ADG was 0.62 using a linear broken-line model and 0.71 using a quadratic model. In Exp. 2 (49 to 70 kg), ADG increased (linear, = 0.021; quadratic, = 0.042) as the SID Val:Lys ratio increased. G:F improved (linear, = 0.039) and serum urea nitrogen (SUN) decreased (linear, = 0.021; quadratic, = 0.024) with an increased SID Val:Lys ratio. The SID Val:Lys ratios to maximize ADG as well as to minimize SUN levels were 0.67 and 0.65, respectively, using a linear broken-line model and 0.72 and 0.71, respectively, using a quadratic model. In Exp. 3 (71 to 92 kg), ADG increased (linear, = 0.007; quadratic, = 0.022) and SUN decreased (linear, = 0.011; quadratic, = 0.034) as the dietary SID Val:Lys ratio increased. The SID Val:Lys ratios to maximize ADG as well as to minimize SUN levels were 0.67 and 0.67, respectively, using a linear broken-line model and 0.72 and 0.74, respectively, using a quadratic model. In Exp. 4 (94 to 119 kg), ADG increased (linear, = 0.041) and G:F was improved (linear, = 0.004; quadratic, = 0.005) as the dietary SID Val:Lys ratio increased. The SID Val:Lys ratio to maximize G:F was 0.68 using a linear broken-line model and 0.72 using a quadratic model. Carcass traits and muscle quality were not influenced by SID Val:Lys ratio. In conclusion, the dietary SID Val:Lys ratios required for 26- to 46-, 49- to 70-, 71- to 92-, and 94- to 119-kg pigs were estimated to be 0.62, 0.66, 0.67, and 0.68, respectively, using a linear broken-line model and 0.71, 0.72, 0.73, and 0.72, respectively, using a quadratic model.
A total of 90 gilts were used to investigate the effects of various standard ileal digestible (SID) total sulfur amino acid (TSAA) to lysine (Lys) ratios on the performance and carcass characteristics of late finishing gilts receiving low crude protein (CP) diets supplemented with crystalline amino acids (CAA). Graded levels of crystalline methionine (Met) (0, 0.3, 0.5, 0.8 or 1.1 g/kg) were added to the basal diet to produce diets providing SID TSAA to Lys ratios of 0.48, 0.53, 0.58, 0.63 or 0.68. At the termination of the experiment, 30 gilts (one pig per pen) with an average body weight (BW) of 120 kg were killed to evaluate carcass traits. Increasing the SID TSAA to Lys ratio increased average daily gain (ADG) (linear and quadratic effect, P < 0.05), improved feed conversion ratio (FCR) (linear and quadratic effect, P < 0.05) and decreased serum urea nitrogen (SUN) concentration (linear and quadratic effect, P < 0.05) of finishing gilts. No effects were obtained for carcass traits. The optimum SID TSAA to Lys ratios to maximize ADG as well as to minimize FCR and SUN levels were 0.57, 0.58 and 0.53 using a linear-break point model and 0.64, 0.62 and 0.61 using a quadratic model.
Antimicrobial peptides (AMPs), produced by several species including bacteria, insects, amphibians and mammals as well as by chemical synthesis and genetically engineered microorganisms, are of great importance in maintaining normal gut homeostasis. AMPs exhibit a broad spectrum of antimicrobial activity and inhibit microbial cells by interaction with their membranes or by other mechanisms, such as inhibition of cell-wall synthesis or suppression of nucleic acid or protein synthesis. In addition to their direct antimicrobial functions, they have multiple roles in the stabilization of epithelial barrier integrity and function as potent immune regulators. The fate of AMPs in vivo is poorly understood, prompting the need for studying AMPs pharmacokinetics. This review summarizes the current knowledge about the basic biology of AMPs and discusses the features of AMPs in gut homeostasis and their relative mechanisms of action.
The study was conducted to determine the standardized ileal digestible (SID) sulfur amino acid (SAA) to lysine (Lys) ratio required to maximize the performance of 25-50 kg pigs fed reduced crude protein (CP) diets fortified with crystalline amino acids.A total of 360 crossbred (Duroc × (Landrace × Large White)) pigs, weighing 25.6 ± 2.7 kg, were blocked by gender, litter, and initial body weight (BW) and allotted to 1 of 5 dietary treatments with 6 pens per treatment and 12 pigs per pen for a 35-day performance trial.The basal diet was based on corn, soybean meal, and wheat bran and was formulated to be deficient in SAA (50% proportion of SID SAA to Lys).Graded levels of dl-methionine were added to the basal diet at the expense of wheat bran in order to provide 55.6, 60.0, 65.6, or 70.0%proportion of SID SAA to Lys, respectively.A constant SID Lys level of 0.90% was set so that Lys was the second limiting amino acid (AA) in all diets.Average daily gain (ADG) and feed conversion ratio (FCR) improved (linear and quadratic, P < 0.05) with increasing dietary proportion of SID SAA to Lys.Increasing the dietary proportion of SID SAA to Lys decreased the serum urea nitrogen (SUN) level (quadratic, P < 0.05).A two-slope broken-line model estimated the optimum proportion of SID SAA to Lys to be 62.2, 61.5, and 62.3% for maximum ADG and minimum FCR and SUN, respectively, whereas a curvilinear-plateau model yielded an optimum proportion of SID SAA to Lys level of 63.8, 62.5, and 61.5% for maximum ADG and minimum FCR and SUN, respectively.Based on an average of these estimates, we conclude that the proportion of SID SAA to Lys required for 25-50 kg pigs fed low CP diets is 62.3%.This estimate is higher than the NRC (2012) recommendation of 56.1% for 25-50 kg pigs fed normal CP diets.
This experiment was conducted to determine the apparent (AID) and standardized ileal digestibility, (SID) of crude protein (CP) and amino acids (AA), the digestible (DE), metabolizable (ME) and calculated net energy (NE) values of screw-pressed camelina cake (SPCC) fed to growing pigs. Six ileal cannulated barrows [(Yorkshire-Landrace)×Duroc] with an average BW of 80kg were assigned to two experimental diets in a two period crossover design to give six observations per diet. Each period lasted for 10d; the initial 5d for diet adaptation, followed by 3d for urine and feces collection, and 2d for ileal digesta collection. Pigs were fed either a corn–soybean meal basal diet formulated to meet NRC (1998) (Nutrient Requirements of Swine, 10th ed. National Academic Press, Washington, DC) nutrient requirements for 50 to 80kg pigs or the basal diet with a portion of the corn and soybean meal replaced by 200g/kg SPCC. The daily feed allowance was set at 40g/kg BW at the beginning of each period and offered in two equal portions at 0800 and 1600h. Titanium dioxide (3g/kg) was included as an indigestible marker. The AID and SID of CP and AA as well as DE and ME values in SPCC were determined by the difference method. The SID of CP and AA was calculated using published values for basal endogenous AA losses obtained from our laboratory and NE was calculated using the determined components from chemical analyses. The GE, CP, lysine, methionine, threonine, ether extract, NDF, ADF and glucosinolate contents of SPCC (on a DM basis) were 21.5MJ/kg, 381, 18, 6.8, 16.8, 119, 315, 203g/kg and 36.3μmol/g, respectively. The SID coefficient of CP for SPCC was 0.65. The coefficient of SID of lysine, methionine and threonine for SPCC were 0.58, 0.53 and 0.53, respectively. The DE, ME, and calculated NE values of SPCC were 17.5, 16.2 and 10.2MJ/kg, respectively. In conclusion, SPCC has potential as an energy source given its remaining oil content, however, its digestibility coefficients for AA and CP were low, and could limit its utilization in swine diets. The SID AA, DE, ME, and calculated NE values of SPCC obtained from the current study could be used when formulating diets and to obtain predictable animal performance.
Sublancin, a bacteriocin, has bactericidal activity against a broad spectrum of gram-positive bacteria. However, studies have not been conducted to determine its in vivo efficacy against potential pathogens. The objective of this study was to investigate the effects of sublancin in a Staphylococcus aureus (S. aureus) infected mouse model which induced intestinal injury. A total of 160, 4-week-old mice were randomly assigned to one of eight treatments. Mice in the control group were injected intraperitoneally with 0.5 mL of 0.9% saline. Mice in the other seven groups were given an intraperitoneal injection of 0.5 mL saline containing 1.0 × 10(10) colony-forming units (CFU)/mL S. aureus. Six hours after inoculation, mice in the control group were again injected with 0.5 mL of 0.9% saline. Mice in the other seven groups were injected intraperitoneally with 0.5 mL of 0.9% saline containing 0, 0.5, 1.0, 2.0, or 4.0 mg/kg body weight (BW) sublancin or 1.0 or 2.0 mg/kg BW ampicillin. The results showed that 4.0 mg/kg sublancin and 2.0 mg/kg ampicillin significantly reduced mice mortality from 55 to 10%. The height and the number of proliferated cells from the intestinal villi in the sublancin and ampicillin treated mice were higher than in the control. We conclude that sublancin has potent antibacterial activity against S. aureus. Therefore, sublancin could find use as an alternative antimicrobial agent for the treatment of gram-positive bacterial infections.
Optimum standardized ileal digestible (SID) tryptophan (Trp) to lysine (Lys) ratio was estimated for 67-96 kg barrows fed low protein diets supplemented with crystalline amino acids (AA). One hundred and fifty Yorkshire × Landrace barrows, with an average initial body weight (BW) of 67.3 ± 3.2 kg, were used in a 28-day feeding trial. All dietary treatments were based on corn, wheat bran, and soybean meal and were formulated to provide 10.5% crude protein and 12.6 MJ/kg metabolizable energy. The dietary SID Lys was set at 0.61% ensuring that Lys was marginally deficient for barrows of this weight range. Graded levels of crystalline l-Trp were added to the basal diet to produce diets providing SID Trp to Lys ratios of 0.131, 0.164, 0.197, 0.230, and 0.262. There were improvements in weight gain (linear and quadratic effect P < 0.01) and feed intake (linear effect P = 0.04) with increasing dietary SID Trp to Lys ratio. Increased SID Trp to Lys ratio resulted in a decrease in the serum urea nitrogen (SUN) content (linear and quadratic effect P < 0.01). The serum concentration of Trp increased with increasing dietary SID Trp to Lys ratio (linear effect P = 0.03, quadratic effect P = 0.08). Estimates of the optimum SID Trp to Lys ratios were 0.203, 0.197, and 0.214 for weight gain, feed conversion ratio, and SUN, respectively, using a broken-line model while a quadratic model produced optimum SID Trp to Lys ratios of 0.251, 0.224, and 0.249 for the same parameters. The results of this experiment indicate that the SID Trp to Lys ratio for finishing barrows is at least 0.203, which is higher than the SID ratio of Trp to Lys currently recommended by the National Research Council (NRC, 2012).
This experiment determined the effects of including normal and low-phytate peas in diets fed to young broiler chickens on performance, phosphorus availability and bone strength. A total of 180, day-old, male broilers (Ross-308 line) were assigned to six treatments. The control was based on corn and soybean meal while two additional corn-based diets were formulated containing 30% of either normal or low-phytate pea providing 0.45% available phosphorus. For each of these three diets, a similar diet was formulated by reducing the amount of dicalcium phosphate to produce a diet with 0.3% available phosphorus. The total tract apparent availability (TTAA) of phosphorus was higher (p = 0.02) for broilers fed the low-phytate pea than for birds fed the normal pea diets. Birds fed diets containing the lower level of phosphorus had a higher TTAA of phosphorus (50.64 vs. 46.68%) than broilers fed diets adequate in phosphorus. Protein source had no effect on weight gain, feed intake or feed conversion. Broilers fed the low phosphorus diets had lower weight gain (p = 0.04) and feed intake (p < 0.01) than broilers fed the higher phosphorus level. Bone strength was higher (p < 0.01) for broilers fed diets based on low-phytate pea than for those fed diets based on normal pea or soybean meal. Increasing the availability of the phosphorus in peas could mean that less inorganic phosphorus would be required in order to meet the nutritional requirements of broilers. Since inorganic phosphorus sources tend to be expensive, a reduction in their use would lower ration costs. In addition, increased availability of phosphorus would reduce the amount of phosphorus excreted thus reducing the amount of phosphorus that can potentially pollute the environment.