Fate of transgenic soybean DNA and immune response of broilers fed genetically modified DP-3Ø5423-1 soybean.

Increased use of genetically modified (GM) plants in the food and feed industry has raised several concerns about the presence of unwanted genes in the food chain and potential associated health risks. In recent years, several studies have compared the nutrient contents of GM crops to conventional counterparts, and some have also tracked the fate of novel DNA fragments and proteins in the gastrointestinal (GIT) and their presence in several tissues. This study was conducted to investigate the fate of transgenic PHP19340A DNA fragment containing gm-fad2-1 (Soybean Event DP-3Ø5423-1) gene in digestive tract contents, blood, internal organs, and muscle tissues. The effects of feeding DP-3Ø5423-1 full-fat soybean meal (FFSBM) to broiler chickens on immune response and blood profiles were also evaluated on d 35. Day-old Ross 308 birds (n = 480) were randomly allocated to 24 floor pens in a 2 × 2 factorial arrangement with diet and gender as main factors. Birds were fed diets containing 20% of either DP-3Ø5423-1 or non-GM FFSBM for 35 d. Data were subjected to a 2-way ANOVA using the GLM procedure of JMP (Pro13). Based on PCR analysis, transgenic PHP19340A DNA fragment containing gm-fad2-1 gene was degraded throughout the digestive system to reach undetectable level in the cecal digesta. Moreover, there was no transgenic gene translocation to blood, organs, or muscle tissue. Feeding DP-3Ø5423-1 FFSBM to broilers had no effect on mRNA abundance of IL-1ß, IL-2, IL-6, IL-12B, IL-17A, IFNγ, TNFα, and NF-κB in the spleen or on blood profile. In conclusion, these findings indicate that the examined transgenic fragment in DP-3Ø5423-1 FFSBM progressively degraded in the GIT and did not translocate into blood or tissues. Along with the immune response and blood profile findings, it can be assumed that DP-3Ø5423-1 soybean is safe and unlikely to pose any health risks to broilers or consumers.

Effect of phased reduction of dietary digestible lysine density on growth performance, thigh meat, and biomechanical characteristics of tibia in broiler chickens.

In this study, growth performance, nutrient intake, thigh meat quality, fatty acid composition of thigh meat, and biomechanical characteristics of tibia of broiler chickens in response to phased restriction of dietary digestible lysine (dLys) were evaluated. A total of 180 male broiler chickens distributed to 3 experimental groups were fed control diets, 85% dLys diet in grower phase (GRO 85% dLys), or 85% dLys diets in grower and finisher phases (GRO-FIN 85% dLys). Feeding 85% dLys suppressed the feed intake that suppressed the growth performance, slaughter weight, and thigh weight of broiler chickens compared to control group (P < 0.05). Average daily dLys, Ca, and P intakes were suppressed in groups fed 85% dLys diets in comparison with control group (P < 0.05) due to the suppression of feed intake. While most fatty acid concentrations in thigh meat were not different among the groups, eicosanoic acid (C20:0) in thigh meat was greater in GRO-FIN 85% dLys group than control group (P = 0.002). Antioxidant status of thigh meat of broiler chickens was not affected by the phased restriction of dietary dLys compared to control group. Bone breaking strength and ultimate strength were greater in control group than 85% dLys groups (P < 0.05). In conclusion, phased dilution of dietary dLys to 85% of the required allowance yields weaker legs and tibia bones by suppressing the Ca and P intakes as a function of reduced feed intake in broiler chickens.

Performance and gut health status of broilers fed diets supplemented with two graded levels of a monoglyceride blend.

The present study was undertaken to evaluate the efficacy of 2 graded levels (0.03 and 0.05% of diet) of a monoglyceride blend containing butyric, caprylic, and capric acids in broilers' diet for optimizing gut structure and animal growth performance. For this purpose, a total of 210, one-day-old male Ross 308 broiler chicks were randomly allocated to 3 experimental treatments using 7 replicates each and 10 birds/replicate. The treatment groups involved supplementation of blend of short and medium chain fatty acids at the level of 0, 0.03, and 0.05% of the diet for 42 d. The incorporation of mixes of monoglycerides into broilers' diet linearly improved BWG between d 0 and 21 (P = 0.034). At the end of trial, however, no significant changes were observed in performance indexes (BWG, FI, FCR). Jejunal morphometric parameters (villus height, crypt depth, and their ratio) remained unaltered with the monoglyceride supplementation on d 21. The results further showed that monoglycerides supplementation increased the goblet cell counts along the jejunal villi (P = 0.034) and crypt regions (P = 0.022), as well as it effectively modulated the mRNA abundances of tight junction protein (ZO-1, P = 0.033) and nutrient transporters (SGLT, PePT1; P = 0.005, 0.023, respectively) in the jejunum. Moreover, the downregulation in mRNA abundance of TNFα (P = 0.030) was observed with the monoglyceride supplementation. The SCFAs analysis of cecal contents showed no notable differences with monoglyceride blend supplementation when compared to the unsupplemented group. Collectively, high goblet cell numbers in the jejunum along with downregulation of the mRNA abundances of pro-inflammatory cytokines, upregulation of tight junction proteins, and nutrient transporters showed favorable responses of low doses of monoglycerides blend in broiler feeding. Further studies should be conducted in different rearing conditions to examine the effectiveness of such low levels of a monoglyceride blend in the modulation of gut structure, its functionality and animal performance.

Influence of dietary vitamin E and selenium supplementation on broilers subjected to heat stress, Part II: oxidative stress, immune response, gut integrity, and intestinal microbiota.

This study evaluated the effects of vitamin E (Vit E) and selenium (Se) supplementation on mRNA abundance of antioxidant, immune response, and tight junction genes, as well as taxonomic and functional profiles of ileal microbiota of broilers exposed to daily 4-h elevated temperature during d 28 to 35. A total of 640-day-old Cobb male broiler chicks were randomly allocated to 32 floor pens in a 2 × 2 factorial arrangement that included ambient temperature (thermoneutral [TN] or heat stress [HS]) and dietary treatments (basal diet or Vit E + Se). Vit E and organic Se were added to the basal diet at the rate of 250 mg/kg and 1 mg/kg, respectively. Liver and jejunum tissue samples were taken on d 27 (1 bird/pen), d 28 and d 35 (2 birds/pen) from birds for qPCR analysis. Data were subjected to a 2-way ANOVA using the GLM procedure of JMP. Ileal contents were taken on d 27 and d 35 for microbial profiling. Microbiota data were analyzed in QIIME 2 and significance between treatments identified linear discriminant analysis effect size (LEfSe, P < 0.05). Dietary Vit E/Se significantly downregulated the mRNA levels of HSPs in liver and jejunal tissues of the HS-challenged birds both on d 28 and d 35. Moreover, mRNA abundance of TLR2, TNFα, IFNγ, IL-1ß, IL-10, and iNOS in the liver were significantly downregulated in birds fed the Vit E/Se diet on d 35. However, dietary treatment had no significant impact on oxidative stress, immunity, and gut integrity related genes analyzed in jejunal tissues on d 28 and d 35, except downregulation of IFNγ on d 35 (P = 0.052). LEfSe analysis revealed that Lachnospiraceae FE2018 and Ruminococcaceae NK4A214 groups was enriched in the Vit E/Se birds on d 35. Moreover, PICRUSt analysis predicted significant functional differences among the treatment groups. In conclusion, dietary supplementation of Vit E/Se mitigated the negative effects of HS potentially via improving antioxidant status, regulating cytokine responses and modifying ileal microbiota and its function.

Influence of dietary vitamin E and selenium supplementation on broilers subjected to heat stress, Part I: Growth performance, body composition and intestinal nutrient transporters.

High ambient temperature is one of the most common stressors in modern poultry production, resulting in reduced feed intake, weight gain, and increased mortality. This study evaluated the effects of vitamin E (Vit E) and organic selenium (Se) supplementation on performance, body composition, core body temperatures, and mRNA abundance of nutrient transporters in the jejunum of broilers exposed to daily 4-h elevated temperature during d 28 to 35. A total of 640 Cobb male birds were randomly allocated to 32 floor pens in a 2 × 2 factorial arrangement that included ambient temperature (thermoneutral, [TN]; or heat stress, [HS]) and dietary treatments (basal diet or Vit E + Se). Four rooms were used (2 TN and 2 HS) each housing half of the 8 replicate pens per group. Vit E and organic Se were added to the basal diet at the rate of 250 mg/kg and 1 mg/kg diet, respectively. Data were subjected to a 2-way ANOVA using the GLM procedure of JMP (SAS). During the HS period, birds fed the Vit E/Se diet had significantly lower mortality compared to nonsupplemented group (1.92% vs. 7.01%). Moreover, dietary Vit E/Se supplementation had a significant effect on performance by increasing BWG, FI, and European production efficiency factor (EPEF) during the entire experimental period (d 0-35). Dietary Vit E and Se supplementation significantly increased carcass, tissue, lean, and fat weights as well as bone mineral content (BMC) and bone mineral density (BMD) on d 35. Birds fed Vit E/Se supplemented diet had significantly lower (P = 0.010) core body temperature compared to birds fed the basal diet on d 30. Dietary treatment did not influence mRNA abundance of PepT1, SGLT1, or NaPi-IIb on d 28 or d 35. However, HS significantly upregulated levels of PepT1 and NaPi-IIb (P < 0.001) and downregulated that of SGLT1 (P = 0.017) on d 28. In conclusion, dietary Vit E and Se supplementation significantly improved broiler growth performance and carcass composition, and reduced heat-related mortality and core body temperature (on d 30) without influencing the mRNA abundance of intestinal nutrient transporters.