Effects of amino acids supplementation in low crude protein diets on growth performance,carcass traits and serum parameters in finishing gilts

This study investigated the effects of amino acids (AA) supplementation in low crude protein (CP) diets on growth performance and carcass characteristics in finishing gilts. One hundred and eighty gilts (59.1 ± 5.1 kg) were randomly allotted to one of five diets which consisted of a high CP (15.6%) diet or four low CP (11.6%) diets for 50 days. The low CP diets were supplemented with lysine + threonine + methionine (LCM), LCM + tryptophan (LCT), LCT + valine (LCV) or LCV + isoleucine (LCI), respectively. Gilts were housed at six pigs per pen with six pens per treatment. At the end of the 50‐day experiment, 30 gilts (one pig per pen) with average body weight (BW) of 98 kg were killed to evaluate carcass traits. The pigs fed the diet supplemented with LCV obtained the highest average daily gain (ADG), which was higher than those of pigs fed the diet supplemented with LCM (P < 0.05). Dietary supplementation with tryptophan, valine and isoleucine in low CP diets increased ADG (linear and quadratic effect, P < 0.05), serum levels of valine (quadratic effect, P < 0.05) and isoleucine (linear and quadratic effect, P < 0.05) and immunoglobulin G (IgG) and IgA (linear and quadratic effect, P < 0.05) in finishing gilts. © 2016 Japanese Society of Animal Science     

Influence of Bacillus subtilis GCB‐13‐001 on growth performance,nutrient digestibility,blood characteristics,faecal microbiota and faecal score in weanling pigs

The present study investigated the influence of Bacillus subtilis GCB‐13‐001 on growth performance, nutrient digestibility, blood characteristics, faecal microbiota and faecal score in weanling pigs. A total of 120 weaning pigs [(Landrace × Yorkshire) × Duroc; 7.73 ± 0.75 kg (28 days of age)] were randomly allotted into three treatments according to their initial body weight (BW) and gender in a 6‐week experiment. There were 8 replication pens in each treatment, with five pigs/pen. Dietary treatment groups were as follows: (a) basal diet (CON), (b) CON + 0.1% Bacillus subtilis GCB‐13‐001 1 × 10⁸ CFU/kg (T1) and (c) CON + 0.1% Bacillus subtilis GCB‐13‐001 1 × 10⁹ CFU/kg (T2). Days 1 to 7, the BW and ADG with T2 treatment were higher (p < .05) than CON treatment, as well as F:G showed trends in linear reduction (p < .1). Days 8 to 21, the BW and ADG were improved (p < .05) in pigs offered T1 and T2 diets compared with CON diet. Days 22 to 42, BW and ADG were higher (p < .05) in pigs fed T2 diet than CON and T1 diets, and the pigs fed T1 diet had higher BW than CON treatment. Overall, the ADG with the T2 treatment was higher (p < .05) than that with the T1 and CON treatments, and pigs offered T1 treatment had higher (p < .05) ADG than CON treatment. Moreover, F:G ratio were significantly decreased (p < .05) by T2 treatment compared with CON treatment. The faecal Lactobacillus counts were improved, and E. coli counts were reduced (p < .05) in pigs fed T2 diet compared with CON at the end of the experiment. In conclusion, supplementation of 0.1% Bacillus subtilis GCB‐13‐001 1 × 10⁹ CFU/kg has shown a beneficial effect in improving BW, increase ADG, decrease F:G ratio.     

Evaluation of standardized ileal digestible lysine requirement for 8–20 kg pigs fed low crude protein diets

Two experiments were conducted to determine the standardized ileal digestible lysine (SID Lys) requirement for weaned pigs fed with low crude protein (CP) diet. In Experiment 1, 144 pigs were fed a normal CP (20%) diet with 12.3 g/kg SID Lys and five low CP (18.5%) diets providing SID Lys levels of 9.8, 11.1, 12.3, 13.5, and 14.8 g/kg, respectively, for 28 days. Reducing dietary CP from 20% to 18.5% enhanced (p < 0.05) the growth performance. The average daily gain (ADG) and gain to feed ratio (G:F) increased (linear and quadratic; p < 0.05), serum urea nitrogen (SUN) decreased (linear and quadratic; p < 0.05) as SID Lys increased. The SID Lys levels required to maximize ADG and optimize G:F were 12.8 and 13.1 g/kg using a curvilinear plateau model, and to minimize SUN was 13.4 g/kg using a two‐slope broken‐line model, which averaged 13.1 g/kg SID Lys. In Experiment 2, 18 pigs were used in a 12‐day N balance trial and received the same diets of Experiment 1. Total N excretion was decreased when dietary CP reduced and further decreased when SID Lys increased. Collectively, 1.5% dietary CP reduction improved the growth performance and decreased the N excretion; the optimal SID Lys requirement was at 13.1 g/kg of 8–20 kg pigs fed with 18.5% CP diet.     

Estimation of the optimum standardized ileal digestible total sulfur amino acid to lysine ratio in late finishing gilts fed low protein diets supplemented with crystalline amino acids

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.     

Investigation of carryover effect of prior fibre consumption on growth,serum and tissue metabolic markers in Ossabaw pigs fed a high‐fat diet

Carryover effect of prior fibre consumption on metabolic markers was investigated. Treatments were arranged in 2 × 2 factorial with 2 fibre sources, 4% inulin or cellulose (Solka‐Floc®) and fat levels (5 or 15%) for the low‐fat diet (LFD) and high‐fat diet (HFD) respectively. Pigs were fed the two fibre diets for the first 56d (nursery phase), and thereafter fed either the LFD or HFD containing no added fibre source from d56 to 140 (growing phase). Pigs on the HFD were heavier (p = .05) than those on LF (64.61 vs. 68.38 kg), regardless of prior fibre type consumed. Pigs that were fed cellulose during the nursery and later fed the HFD had the highest ADG (p < .05). Feeding the HFD resulted in higher back fat (BF) (13.41 and 18.18 ± 0.12 mm for LFD and HFD, respectively; p < .01). The HFD resulted in higher (p < .01) insulin (0.014 and 0.016 ± 0.001 mg/L for LF and HF respectively) and glucose (100.89 and 125.03 ± 4.39 mg/dl for LF and HF respectively) concentrations in the serum. Inulin increased (p ≤ .02) jejunal expression of SREBP‐1c and CL‐4, but reduced (p < .05) TNFɑ and IL‐6 expression in the ileum. Alpha‐diversity was significantly different (p < .05) between the inulin and cellulose fed pigs at the end of the nursery and finishing phases. Therefore, inulin feeding before a HFD may lead to reduction in ADG and inflammatory markers in the small intestine of pigs, and thus prevent future metabolic disorders.     

Effects and interaction of dietary electrolyte balance and citric acid on growth performance,intestinal histomorphology,digestive enzyme activity and nutrient transporters expression of weaned piglets

Fifty-six piglets were weaned at 21 days and randomly assigned to 1 of 8 dietary treatments with 7 replicate pens for a 14-day experimental period. The eight experimental diets were prepared via a 2 × 4 factorial arrangement with citric acid (CA; 0 and 0.3%) and dietary electrolyte balance (dEB, Na +K − Cl mEq/kg of the diet; −50, 100, 250, and 400 mEq/kg). Varying dEB values were obtained by altering calcium chloride and sodium bicarbonate contents. Dietary CA significantly increased (p < .05) villus height (VH) and villus height:crypt depth (VH:CD) in the jejunum. Piglets fed a 250 mEq/kg diet increased (p < .05) VH and VH:CD values in the duodenum. Jejunal VH and VH:CD increased (quadratic; p < .05), and ileal VH:CD (liner and quadratic; p < .05) decreased as dEB was increased in diets without CA, but no such effect was observed on the diets containing CA (dEB ×CA; p < .05). The CD in jejunum (quadratic; p < .05) increased as dEB was increased in diets containing CA, whereas it was decreased (linear; p < .05) in the diets without CA (dEB ×CA; p < .001). Dietary CA increased maltase activity and reduced the number of Ki67-positive cells (p < .05). Increasing dEB values in diets without CA increased sucrose and lactase activities (quadratic; p < .05), but no such effect was observed in the diets with CA (dEB ×CA; p < .05). An interaction effect between dEB and CA on the number of Ki67-positive cells was observed (p < .001). In conclusion, 250 mEq/kg dEB diet with CA improved piglet intestinal digestion and absorption function by improving intestinal morphology and increasing digestive enzyme activities. However, these improvements were also observed in piglets fed the 100 mEq/kg dEB diet without CA.     

Physiological and health‐related response of broiler chickens fed diets containing raw,full‐fat soya bean meal supplemented with microbial protease

A 2 × 3 factorial study (protease: 0 or 1,5000 PROT/kg and raw full‐fat soya bean meal [RSBM] replacing the commercial SBM at 0, 45 and 75 g/kg of diet) was conducted to examine the performance of broilers. Phytase (2000 FYT/kg) was uniformly added to each diet, each also replicated six times, with eight birds per replicate. Birds were raised in climate‐controlled rooms using sawdust as the bedding material and offered starter, grower and finisher diets. Feed intake (FI) and body weight gain (BWG) were reduced (p < .05) due to increasing levels of RSBM, but feed conversion ratio (FCR; 0–35 days) was unaffected. Over the first 24 days, neither RSBM nor protease supplementation affected (p > .05) mortality, footpad dermatitis or intestinal lesions in birds. At day 24, the weight, length, width and strength of tibia bone were reduced in chickens that received an elevated level of RSBM (75 g/kg of diet), but this was not significant at day 35. At day 24 (p < .05) and 35 (p < .01), Ca concentration in the litter was reduced when the RSBM level was increased in the diet, but P content was not affected. On days 24 (p < .05) and 35 (p < .01), the N content in litter was also increased with increase in dietary RSBM. Protease supplementation increased (p < .05) the uric acid concentration in the litter (at day 35), but the reverse was the case for ammonia concentration. Overall, the results of this study indicate that there are no major health‐related risks, associated with the replacement of commercial SBM with RSBM (≤25%) in broiler diets.     

Supplementation of broiler diets with high levels of microbial protease and phytase enables partial replacement of commercial soybean meal with raw,full‐fat soybean

A 3 × 3 + 1 factorial, involving three levels of protease (0, 15,000 or 30,000 PROT/kg) and three levels of phytase (1,000, 2,000 or 3,000 FYT/kg), was used to evaluate the effect of replacing commercial soybean meal (SBM) with raw, full‐fat soybean (RFSB) at 75 g/kg of diet for broilers. A control diet was used for comparison. Each treatment was replicated six times, with nine birds per replicate. The concentration of trypsin inhibitors (TIs) in the test diets was approximately 10,193.4 TIU/kg. Regardless of enzyme supplementation, feed intake (FI) and body weight gain (BWG) of birds in the control group were superior to those on the test diets. Birds that received the protease‐free test diets had reduced FI and BWG, but when supplemented with protease, were similar to the control diet in BWG, FI (except 0–35 days) and feed conversion ratio (FCR). When the test diet was supplemented with elevated levels (extradose) of protease and phytase, the BWG was improved during 0–10 days (p = .05) and 0–24 days (p < .01). Regardless of protease supplementation, the weight of thighs was lower for birds fed the test diets. Birds that received the control diet had smaller weight of pancreas. Increasing the level of phytase supplementation reduced (p < .05) the weight of the pancreas. The apparent ileal digestibility (AID) of CP and AA was higher in birds on the control diets, but this was also improved in test diets by protease supplementation. The activities of trypsin (7%), general proteolytic (11%) and lipase (12%) were slightly increased because of protease supplementation. Mucosal depth and apparent villus surface areas were increased by about 2.9% and 20%, respectively, due to supplementation of elevated level of phytase. It can be concluded that RFSB could partially replace SBM in broiler diets, provided the diets are supplemented with elevated levels of protease and phytase.     

Effect of dietary polyphenol‐rich grape seed on growth performance,antioxidant capacity and ileal microflora in broiler chicks

In this study, we examined the effect of dietary supplementation with grape seed (GS) on the performance, carcass traits, plasma biochemistry, antioxidant status and ileal microflora in broilers. Experiment diets included a control diet (without additive) and three levels of GS powder (10, 20 and 40 g/kg of diet). Each diet was fed to a total of 300 one‐day‐old Cobb‐500 chicks for 42 days. The addition of 20 g/kg of GS to the basal diet increased final body weight and body weight gain, improved the feed conversion ratio and did not affect feed intake. Dietary 20 g GS significantly increased (p < .05) the percentage of carcass yield %, dressing % and gizzard. However, the addition of 40 g/kg of GS significantly reduced the percentage of abdominal fat in the birds. Diets supplemented with GS showed the lowest content of ether extract compared with the control group (p < .05). The physical characteristics of meat and the chemical composition of DM, CP and ash were not significantly influenced by treatments. In the GS groups, plasma protein, albumin, globulin, aspartate aminotransferase and alanine aminotransferase concentrations showed no significant change compared with the control group. Broilers fed a diet supplemented with GS had lower levels of plasma glucose, total lipids, triglycerides and cholesterol compared with the control birds (p < .05). The addition of 40 g of GS significantly (p < .05) enhanced the activity of reduced glutathione, catalase, superoxide dismutase, glutathione peroxidase and GST, and correlated with significantly decreased thiobarbituric acid‐reactive substances levels compared with the control group. The value of ileal pH was not significantly affected by the GS levels. Broilers fed diets supplemented with GS had lower ileal Streptococcus spp. and Escherichia coli populations but higher Lactobacillus spp. populations (p < .05). No adverse effects on birds’ health were detected due to the use of GS. Thus, GS could be recommended as an herbal supplement in the diet of broiler chickens to improve performance, reduce blood lipids, enhance antioxidant capacity and decrease detrimental bacteria in the ileum.     

Genotype and dietary lysine deficiency affect carcass and muscle amino acid composition of pigs growing from 10 to 25 kg body weight

Amino acid (AA) composition of body protein is considered constant although there are evidences that AA pattern in pigs may be altered by different factors. Pigs with different body composition and protein deposition rates—like fatty and lean pigs—may differ in AA composition, with possible consequences on their AA requirements. This work investigates effects of genotype and dietary lysine deficiency on AA composition of carcass and muscles of Iberian and Landrace × Large White pigs. Twenty‐eight barrows (10 kg body weight [BW]), 14 from each breed, were used. They were randomly assigned to two experimental diets according to a factorial arrangement (two breeds × two diets). Diets were isonitrogenous and isoenergetic (200 ± 1 g CP/kg dry matter (DM); 14.7 ± 0.1 MJ ME/kg DM) and with identical chemical composition except for lysine concentration (10.9 and 5.20 g lysine/kg DM, for lysine‐adequate (AL) diet and lysine‐deficient (DL) diet respectively). Pigs were individually housed, and daily feed allowance was adjusted on a weekly basis according to BW. Pigs were slaughtered at 25 kg BW. Isoleucine, valine and phenylalanine concentration were higher in carcass protein of Iberian pigs (p < .01). In longissimus muscle, higher concentration of arginine, isoleucine, phenylalanine, lysine and valine (p < .001–p < .05), and lower of methionine (p < .001) were detected in Iberian pigs, whereas phenylalanine, leucine, lysine, threonine and methionine concentration decreased and arginine increased (p < .001–p < .05) when pigs were fed DL diet. Genotype and lysine deficiency effects were moderate in the AA composition of protein of biceps femoris muscle. The results show that AA proportions in protein of carcass and longissimus muscle can be influenced by pig genotype and conditions of lysine shortage. The biceps femoris muscle, with different functional and metabolic properties, shows more constant AA composition than longissimus, which seem to prevail independent from genotype or nutritional challenges.     

Comparative study of stress response,growth and development of uteri in post‐weaning gilts challenged with zearalenone and estradiol benzoate

The objective of this study was to evaluate the effects of zearalenone (ZEA) and estradiol benzoate (EB) on stress injury and uterine development in post‐weaning gilts. Thirty healthy post‐weaning female gilts (Duroc × Landrace × Large White) aged 28–32 days were randomly allocated to three treatments as follows: (a) basal diet (Control), (b) basal diet plus 1.0 mg/kg purified ZEA (ZEA) and (c) basal diet plus 0.75 ml (1.5 mg) EB per pig at 3‐days intervals by intramuscular injection (EB). The serum estradiol (E₂), the final and the increased vulvar area, uterine index, thickness of the myometrium and endometrium, and protein expression of heat shock protein 70 (HSP70) in ZEA group were higher than those in the control group (p < .05), but lower than those in the EB group (p < .05). The serum luteinizing hormone in ZEA group was lower than that of the control group (p < .05), but higher than that in the EB group (p < .05). Higher serum follicle‐stimulating hormone and progesterone were observed in the ZEA and control groups than those in the EB group (p < .05). The serum glutathione peroxidase activity in the ZEA group was lower than that in the control and EB groups (p < .001), and the malondialdehyde in the ZEA group was higher than that in the control and EB groups (p < .001). Moreover, the relative mRNA and protein expression of growth hormone receptor (GHR) and relative mRNA expression of HSP70 in the ZEA and EB groups were higher than those in the control group (p < .05). In conclusion, both ZEA (1.0 mg/kg) and EB (1.5 mg at 3 days intervals by intramuscular injection) stimulated vulvar swelling and uterine hypertrophy by disordering serum hormones and up‐regulating GHR expression, and induced stress by different mechanisms in this study. Furthermore, the observed up‐regulating HSP70 expression challenged by ZEA or EB may be part of the mechanism to resist stress injury.     

Effects of dietary fibre level and body weight of pigs on nutrient digestibility and available energy in high‐fibre diet based on wheat bran or sunflower meal

The objectives of this study were (a) to investigate the effect of body weight (BW) on available energy in fibre‐rich diets containing two NDF levels; and (b) to evaluate the effect of fibre type and NDF level on AA digestibility. In Exp. 1, barrows (24 at 33.4 ± 1.1 kg; 24 at 86.8 ± 3.3 kg) were randomly allotted to 4 diets containing a high protein basal (HPB), a low protein basal (LPB), 70% HPB + 30% wheat bran (WB) (HPB‐WB) and 70% LPB + 30% sunflower meal (SFM) (LPB‐SFM). In Exp. 2, barrows (24 at 33.5 ± 1.8 kg; 24 at 87.0 ± 3.8 kg) were randomly allotted to 4 diets containing no SFM with 12% NDF (SFM0LF), no SFM with 16% NDF (SFM0HF), 24% SFM with 12% NDF (SFM24LF) and 24% SFM with 16% NDF (SFM24HF). In Exp. 3, twelve barrows (35.5 ± 3.4 kg) fitted with T‐cannulas were allotted to two 6 × 4 Youden square design with 6 diets (4 same diets as in Exp. 2 and 2 nitrogen‐free diets). The concentration of DE, ME and ATTD of GE, CP, NDF and ADF in diets was greater (p < .01) when fed to 90 kg pigs compared with 30 kg pigs. The ME in ingredients was not affected by BW. The ATTD of NDF was negatively correlated with the CF (r = ?.98; p < .01), ADF (r = ?.99; p < .01) and ADL content (r = ?.96; p < .01). The ME of diets was negatively correlated with the ATTD of CF (r = ?.98; p < .01). The addition of SFM increased the standardized ileal digestibility (SID) of Met (p < .05). In conclusion, diets rich in fibre had different nutritional values at different pig weight stages. The AA digestibility depends mainly on chemical composition of diets.     

Effect of dietary supplementation of calcium butyrate on growth performance,carcass traits,intestinal health and pro‐inflammatory cytokines in Japanese quails

The objective of the present study was to evaluate the potential effect of dietary calcium butyrate on growth performance, carcass traits and gut health in Japanese quails. In total, 320 one‐day‐old Japanese quails were randomly assigned to 4 equal treatments, with 8 replicates of 10 Japanese quails, for 4 weeks. The Japanese quails in control treatment were fed control diet whereas in the other treatments the Japanese quails were fed diet supplemented with calcium butyrate at 0.3, 0.5 and 0.7 g/kg diet. Data concerning performance measurements were recorded weekly. In addition, eight Japanese quails (one/replicate) from each treatment were selected randomly for serum collection to measure pro‐ and anti‐inflammatory cytokines. Pooled faecal samples from each replicate of each treatment were also collected at three time points (0, 2 and 4 weeks) for count E. coli and C. perfringens. The results showed that after 7 days of the experimental period, Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg showed a greater (p < .05) body weight and a favourable (p < .05) feed conversion ratio than the other treatments. Moreover, serum superoxide dismutase and catalase activities were increased (p < .05) in Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg. Calcium butyrate supplementation at 0.7 g/kg was associated with reduction (p < .05) in TNF‐α, IL‐6 and IL1‐β, while IL‐10 was increased (p < .05). In addition, after 2 weeks of calcium butyrate supplementation, a reduction (p < .05) in E. coli and C. perfringens counts was observed in excreta of Japanese quails fed 0.5 and 0.7 g calcium butyrate/kg diets. It is concluded that calcium butyrate supplementation improves body weight gain, reduces E. coli and C. perfringens counts and has anti‐inflammatory/anti‐oxidant effect in Japanese quails.     

Effect of protease derived from Pseudoalteromonas arctica supplementation on growth performance,nutrient digestibility,meat quality,noxious gas emission and blood profiles in finishing pigs

This study was conducted to evaluate the effects of dietary supplementation of protease derived from Pseudoalteromonas arctica (PPA) in finishing pigs. A total of 160 pigs were used in this 10‐week trial. Dietary treatment groups were as follows: CON (basal diet); TRT1 (basal diet + 0.1% PPA); TRT2 (basal diet + 0.2% PPA); and TRT3 (basal diet + 0.3% PPA). During weeks 1–5, pigs fed with different levels of PPA‐supplemented diet showed linear increase (p < .05) in the apparent total tract digestibility (ATTD) of nitrogen (N) and linear decrease (p < .05) in the concentrations of serum total protein. During weeks 6–10, pigs fed with different levels of PPA‐supplemented diet showed a linear decrease in feed conversion ratio (p < .05). During the overall period, there was a linear decrease in feed conversion ratio (p < .05) associated with the inclusion of PPA. Pigs fed diets with 0.2% PPA supplementation had lower (p < .05) feed conversion ratio than those fed CON diet during weeks 6–10 and the overall period, and had higher (p < .05) ATTD of N than those fed CON diet during weeks 1–5. Pigs fed diets with PPA supplementation had lower (p < .05) concentrations of serum total protein than those fed CON diet on week 5. In conclusion, dietary supplementation with PPA diet has beneficial effects on growth performance, nutrient digestibility, backfat thickness and the concentrations of serum total protein.     

Effects of a short‐term supranutritional selenium supplementation on redox balance,physiology and insulin‐related metabolism in heat‐stressed pigs

Heat stress (HS) disrupts redox balance and insulin‐related metabolism. Supplementation with supranutritional amounts of selenium (Se) may enhance glutathione peroxidase (GPX) activity and reduce oxidative stress, but may trigger insulin resistance. Therefore, the aim of this experiment was to investigate the effects of a short‐term high Se supplementation on physiology, oxidative stress and insulin‐related metabolism in heat‐stressed pigs. Twenty‐four gilts were fed either a control (0.20 ppm Se) or a high Se (1.0 ppm Se yeast, HiSe) diet for 2 weeks. Pigs were then housed in thermoneutral (20°C) or HS (35°C) conditions for 8 days. Blood samples were collected to study blood Se and oxidative stress markers. An oral glucose tolerance test (OGTT) was conducted on day 8 of thermal exposure. The HS conditions increased rectal temperature and respiration rate (both p < .001). The HiSe diet increased blood Se by 12% (p < .05) and ameliorated the increase in rectal temperature (p < .05). Heat stress increased oxidative stress as evidenced by a 48% increase in plasma advanced oxidized protein products (AOPPs; p < .05), which may be associated with the reductions in plasma biological antioxidant potential (BAP) and erythrocyte GPX activity (both p < .05). The HiSe diet did not alleviate the reduction in plasma BAP or increase in AOPPs observed during HS, although it tended to increase erythrocyte GPX activity by 13% (p = .068). Without affecting insulin, HS attenuated lipid mobilization, as evidenced by a lower fasting NEFA concentration (p < .05), which was not mitigated by the HiSe diet. The HiSe diet increased insulin AUC, suggesting it potentiated insulin resistance, although this only occurred under TN conditions (p = .066). In summary, HS induced oxidative stress and attenuated lipid mobilization in pigs. The short‐term supranutritional Se supplementation alleviated hyperthermia, but did not protect against oxidative stress in heat‐stressed pigs.     

Branched‐chain amino acid ratios in low‐protein diets regulate the free amino acid profile and the expression of hepatic fatty acid metabolism‐related genes in growing pigs

Liver metabolism is affected by nutrients. The aim of this study was to explore the effects of low‐protein diets (17% crude protein, CP) supplemented with branched‐chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile) and valine (Val), on hepatic amino acid profile and lipid metabolism in growing pigs. The ratio of Leu : Ile : Val in all groups was 1 : 0.51 : 0.63 (20% crude protein, CP), 1 : 1 : 1 (17% CP), 1 : 0.75 : 0.75 (17% CP), 1 : 0.51 : 0.63 (17% CP) and 1 : 0.25 : 0.25 (17% CP) respectively. Results revealed that compared to the positive control group (1 : 0.51 : 0.63, 20% CP), the low‐protein diets significantly augmented the concentrations of most essential amino acids and non‐essential amino acids (p < .05), with the greatest values observed in the 1 : 0.25 : 0.25 group. Moreover, relative to the control, the low‐protein diets with the Leu : Ile : Val ratio ranging from 1 : 0.75 : 0.75 to 1 : 0.25 : 0.25 markedly downregulated the mRNA abundance of acetyl‐CoA carboxylase (ACC), lipoprotein lipase (LPL) and fatty acid‐binding protein 4 (FABP‐4) (p < .05), and upregulated the mRNA expression of hormone‐sensitive lipase (HSL), peroxisome proliferator‐activated receptor‐g coactivator‐1α (PGC‐1α), uncoupling protein 3 (UCP3) and liver carnitine palmitoyltransferase 1 (L‐CPT‐1) (p < .05). Therefore, our data suggest that protein‐restricted diets supplemented with optimal BCAA ratio, that is, 1 : 0.75 : 0.75–1 : 0.25 : 0.25, induce a shift from fatty acid synthesis to fatty acid oxidation in the liver of growing pigs. These effects may be associated with increased mitochondrial biogenesis.     

Effects of chestnut tannins on intestinal morphology,barrier function,pro‐inflammatory cytokine expression,microflora and antioxidant capacity in heat‐stressed broilers

A study was conducted to evaluate the effects of chestnut tannins (CT) on intestinal morphology, barrier function, pro‐inflammatory cytokine expression, microflora and antioxidant capacity in heat‐stressed broilers. Four hundred 28‐day‐old male Ross 308 broilers were randomly assigned into four groups, with 10 replicates per group and 10 broilers per replicate. The broilers in the normal (NOR) group were kept at 22 ± 1°C and fed the basal diet, and each of the other three groups were treated with cyclic heat (33 ± 1°C from 0800 to 1800 and 22 ± 1°C from 1800 to 0800) and fed the basal diet with 0 (HT), 1 (CT1) or 2 (CT2) g of CT/kg of diet. The experiment lasted for 14 days. Compared with the HT group, broilers in the NOR and CT2 groups had higher (p < .05) average daily gain and villus height in the jejunum and lower serum d ‐lactate (p < .001) and diamine oxidase (p < .01) levels. The addition of 2 g CT/kg of diet increased the total antioxidant capacity (p < .001) and superoxide dismutase activities (p < .05) and zonula occludens‐1 mRNA expression level (p < .05) and decreased the malondialdehyde concentration (p < .01) and mRNA expression levels of interleukin‐6 (p < .001) and nuclear factor kappa B (p < .001) in the jejunal mucosa of heat‐stressed broilers. The populations of Escherichia coli and Clostridium in the jejunum (p < .01) and caecum (p < .05) of broilers in the HT group were higher than those in the NOR and CT2 groups. In conclusion, the addition of 2 g CT/kg of diet seemed to be a feasible means of alleviating the negative effects of heat stress on the growth performance and intestinal function of broilers.     

Effects of multistrain probiotics on growth performance,nutrient digestibility,blood profiles,faecal microbial shedding,faecal score and noxious gas emission in weaning pigs

This experiment was conducted to investigate the efficacy of multistrain probiotics in weaning pigs. A total of 125 28‐day‐old weaning pigs [(Landrace × Yorkshire) × Duroc] with an initial average body weight (BW) of 7.26 ± 0.76 kg were randomly allotted into 5 treatments, 5 replicate pens/treatment with 5 pigs/pen for 42‐day experiment. Dietary treatments were as follows: CON, basal diet; PC1, CON + 0.01% multistrain probiotics; PC2, CON + 0.03% multistrain probiotics; PC3, CON + 0.06% multistrain probiotics; PC4, CON + 0.1% multistrain probiotics. On day 14, pigs fed the PC4 diet had higher BW gain than pigs fed the CON diet. On day 42, pigs fed multistrain probiotics supplementation diets had higher BW gain than pigs fed the CON diet. From days 1 to 14, pigs fed the PC2, PC3 and PC4 diets had higher (p < 0.05) ADG than pigs fed the CON diet. From day 15 to 42, pigs fed the multistrain probiotics supplementation diets had higher (p < 0.05) average daily gain (ADG) and gain: feed ratio (G:F) than pigs fed the CON diet. In the overall period, pigs fed the multistrain probiotics supplementation diets had higher (p < 0.05) ADG and pigs fed the PC2 and PC4 diets had higher (p < 0.05) G:F than pigs fed the CON diet. On day 42, pigs fed the PC4 diet had higher (p < 0.05) apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N) and gross energy (GE), faecal Lactobacillus counts and lower (p < 0.05) E. coli counts and NH₃ emission than pigs fed the CON diet. Pigs fed the multistrain probiotics supplementation diets had lower (p < 0.05) H₂S and total mercaptans emissions than pigs fed the CON diet. Conclusions, dietary supplementation with 0.1% probiotics improved growth performance, nutrition digestibility and intestinal microflora balance and decreased faecal noxious gas emissions in weaning pigs.     

Dietary lysine requirement for 7–16 kg pigs fed wheat–corn–soybean meal‐based diets

Two experiments were conducted to determine the lysine requirement of weaned pigs [Duroc × (Yorkshire × Landrace)] with an average initial BW of 7 kg and fed wheat–corn–soybean meal‐based diets. The experiments were conducted for 21 days during which piglets had free access to diets and water. Average daily gain (ADG), average daily feed intake (ADFI) and gain to feed ratio (G:F) were determined on day 7, 14 and 21. Blood samples were collected on day 0 and 14 to determine plasma urea nitrogen (PUN) concentration. In experiment 1, 96 weaned pigs were housed four per pen and allocated to four dietary treatments with six replicates per treatment. The diets contained 0.99%, 1.23%, 1.51% and 1.81% standardized ileal digestible (SID) lysine, respectively, corrected analysed values. The rest of the AA were provided to meet the ideal AA ratio for protein accretion. Increasing dietary lysine content linearly increased (p < 0.05) ADG and G:F. In experiment 2, 90 piglets were housed three per pen and allocated to five dietary treatments with six replicates per treatment. The five diets contained 1.03%, 1.25%, 1.31%, 1.36% and 1.51% SID lysine, respectively, corrected analysed values. Increasing dietary lysine content linearly increased (p < 0.05) G:F, linearly decreased (p < 0.05) day‐14 PUN and quadratically (p < 0.05) increased ADG and ADFI. The ADG data from experiment 2 were subjected to linear and quadratic broken‐lines regression analyses, and the SID lysine requirement was determined to be 1.29% and 1.34% respectively. On average, optimal dietary SID lysine content for optimal growth of 7–16 kg weaned piglets fed wheat–corn–SBM‐based diets was estimated to be 1.32%; at this level, the ADG and ADFI were 444 and 560 g, respectively, thus representing an SID lysine requirement, expressed on daily intake basis as, 7.4 g/day or 16.76 mg/g gain.