Veterinary Research Forum

Abstract Crude fiber (CF) is a vital component in poultry nutrition with a notable phytonutrient effectively indicating the presence of indigestible biomass in food due to the absence of digestive enzymes for CF in broilers. This study aimed to analyze the properties of a multi-enzyme cocktail (MEC) Bacillus sonorensis BD92 (BsBD92) comprised of xylanase, β-glucosidase, exo-glucanase, and endo-glucanase enzymes. Also, this study intended to look at the growth performance and intestinal histology of broilers in the starter and finisher phases by the addition of MEC BsBD92 to their diet. To evaluate the efficacy of MEC BsBD92, 140 one-day-old unsexed Cobb500 broiler chicks were randomly divided into seven groups receiving different diets. The characterization of exo-glucanase, xylanase, β-glucosidase, and endo-glucanase showed that their peak activities were observed at a temperature of 50.00 ˚C and a pH of 5.50. The 6.00% CF and 2.00 X MEC BsBD92 improved the intestinal morphology and feed conversion ratio, demonstrating a synergistic effect on growth performance. Whereas, increasing meat percentages to 61.06 and 65.09 g per 100 g body weight during the starter and finisher phases was also observed, respectively. The lipid profiles revealed significant variations in triglyceride and cholesterol levels. This study provides an innovative approach, considering not only lowering the feed cost using inexpensive fibrous feedstuffs but also improving the feed efficiency through supplementation of MEC BsBD92.

Abstract Japanese quail (Coturnix coturnix japonica) is a popular experimental animal model in scientific research. The present study investigated the effects of dietary multiple enzyme supplementation on growth performance, carcass characteristics, nutrient digestibility and small intestinal histomorphology in quails fed diets based on wheat and soya bean meal. A total number of 192 1-day-old quails were assigned to three treatments with 16 replicates in each and four quails per replicate for 38 days.  The control group received a basal diet, and the treatment groups received a basal diet with 0.10 or 0.20% multi-enzyme, respectively. Growth performance parameters, carcass characteristics, nutrient digestibility and small intestinal histomorphology in quails were evaluated. Dietary supplementation of multi-enzymes to diet significantly increased body weight gain and improved the feed conversion rate. Moreover, quails fed with 0.10 or 0.20% multi-enzymes showed better ash digestibility coefficients and apparent metabolizable energy coefficients than the control quails. Furthermore, quails fed on a diet containing 0.20% multi-enzyme had the highest crude fiber digestibility. The villi length and the villi length/crypt depth ratio of the duodenum were significantly increased and the crypt depth was decreased in quails-fed diets supplemented with both multi-enzyme levels. However, feed consumption, carcass yield, carcass weight, heart weight, gizzard weight, liver weight and total intestine weights were not affected by treatments. In conclusion, our results showed that dietary supplementation of multi-enzymes to a wheat and soybean meal-based diet enhanced the growth performance and nutrient digestibility of quails.

Abstract The potential of commercial astaxanthin on growth, biochemical factors, and antioxidant-related gene expression following a challenge with diazinon were studied in rainbow trout (Oncorhynchus mykiss). Fish (~ 20.70 g) were fed diets containing commercial astaxanthin (ASX) at 0.00 (CTR and ASX0), 0.50 (ASX1), 2.00 (ASX2), and 5.00 (ASX3) g kg^-1 for 60 days. Afterwards, the treated fish (ASX1, ASX2, ASX3) as well as the fish in ASX0 group were challenged with diazinon (0.11 mg L^-1) for 96 hr whereas fish in the CTR group was not challenged with diazinon. Results showed that growth pattern improved significantly with all enriched diets compared to the ASX0 group. Metabolic enzyme activities, including alanine aminotransferase and alkaline phosphatase decreased in ASX2 and ASX3 groups with respect to the ASX0 group. Serum antioxidant status also showed the same pattern with enhancement in the fish fed with the ASX2 and ASX3 supplemented diets. Feeding the fish with astaxanthin, particularly in the ASX3 group, up-regulated the expression of some antioxidant-relevant genes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), and nuclear factor erythroid-2 related factor 2 (Nrf2) in the kidney and liver. Besides, the histopathological damages in kidneys and liver induced by diazinon were less pronounced in the ASX2 and ASX3 groups compared to the ASX0 group. In conclusion, commercial astaxanthin, especially at 5.00 g kg^-1, enhanced the growth performance and ameliorated the oxidative stress induced by diazinon in rainbow trout.

Abstract Light-emitting diodes (LEDs) lights are more energy-efficient and provide adequate illumination compared to compact fluorescent (CFL) lamps and incandescent light (ICD) bulbs. However, as new light sources, the LED lights may have a stress effect on broiler chickens. Thus, this study aimed to determine the effects of dietary L-tryptophan (Trp), as an anti-stress agent and different color temperatures of light-emitting diodes on immune responses and growth performance of male broiler chickens. Four hundred and eighty day-old Ross 308 male chicks were used from day 1 to 42. The chicks were randomly distributed into six treatment groups in a 2 × 3 factorial arrangement [0 or 1 g Trp per kg diet along with neutral-white (4286 K), warm-white (2990 K), and incandescent (2790 K) light bulbs] with four replicates of 20 chicks each. Results showed that dietary Trp and Trp×light interaction did not affect growth performance, immune responses, a total number of leukocytes, and different leukocytes count (heterophil, eosinophil, monocyte, and lymphocyte) of male broiler chickens. However, LEDs’ different color temperatures significantly affected the feed conversion ratio (FCR) and primary antibody of sheep red blood cell (SRBC). The FCR was the lowest in the warm-white light, and primary SRBC antibody titers of the chicks were the highest. In conclusion, although adding Trp to male broiler diets did not affect the growth performance and immune responses of chickens, the warm-white light improved the FCR and primary SRBC.

Abstract The present study was carried out to determine the effects of fenugreek powder (FP) and extract (FE) on performance, egg quality, blood parameters and immune responses of laying hens. One-hundred and fifty Leghorn laying hens were used in a completely randomized design with five treatments and five replicates for eight weeks. Treatments were various levels of FP and FE including zero (control; T1), 1.00% FP (T2), 2.00% FP (T3), 0.10% FE (T4) and 0.20% FE (T5).The results of this experiment showed that feed intake was increased linearly by the inclusion of FP compared to the control group. Supplementation of laying hens diet with 2.00% FP adversely affected feed conversion ratio (FCR). The FCR was decreased by 0.10% inclusion of FE compared to 0.20%. Egg yolk color was the highest when 1% FP added to laying hens diets compared to the other treatments. Serum metabolites and immune responses of laying hens were not affected significantly by fenugreek supplementation. From the results of the present study, it can be concluded that using 1.00% FP can improve feed intake by supporting FCR. Inclusion of 1.00% FP in laying hens diet enhanced egg yolk color of laying hens in the second production cycle.

Abstract The aim of this study was to evaluate the feeding of Qizil fattening lambs with different levels of broiler litter (BL) on their weight gain, dry matter intake (DMI), nutrient digestibility, selected blood metabolites and husbandry economics. During an eight-weeks experimental period, 28 male lambs (an average of 42.21 ± 5.63 kg and ages of 7-8 months) were allocated randomly to one of four dietary treatments, including; control diet with no litter (NL, n = 7), diet containing 5% BL (LL, n = 7), diet with 10% BL (ML, n = 7) and diet containing 15.00% BL (HL, n = 7) as dry matter (DM) basis. The lambs were kept in individual pens and had free access to feed and water (ad libitum) throughout the study. In this research, DMI and feed conversion ratio were not influenced significantly by the dietary treatments, while average daily gain (ADG) was found to be significant. The lambs which consumed LL diet (5.00% BL) had the greatest ADG. The DM digestibility significantly influenced by dietary treatments, as the HL diet (15.00% BL) had the least DM digestibility. There were also significant differences in the crude protein and acid detergent fiber digestibility among the treatments. Blood urea nitrogen and glucose levels were significantly affected by the treatments. Low litter treatment had the least FCR and the highest economical advantage. In conclusion, feeding male Qizil lambs with BL can reduce production cost without any negative effects on performance.

Abstract In the present study, chicory root powder (CRP) as growth promoter at 1% and 3% levels was supplemented in broilers’ diet to investigate the growth performance and histo-morphometry of jejunum. One hundred twenty, one-day-old male broilers were used in a completely randomized design (CRD) with 3 treatments and 4 replicates (10 chicks per replicate). At the end of each period (0-10, 11-24 and 0-24 days), feed intake (FI), weight gain (WG), and feed conversion ratio (FCR) were measured. At the end of experiment (day 24), one bird per replicate was sacrificed for breast weight (BW), drumstick weight (DW), and jejunum length (JL) as a percentage of body weight, and histomorphometry of villus. The FI increased by 3% CRP in the 1^st period (p < 0.01). The percentage of WG significantly increased at 1% during the 1^st period and, in the 2^nd and total periods, it increased only at 3% CRP (p < 0.05). The FCR decreased at 1% in the 1^st (p < 0.04) and, at 3% in the 2^nd (p < 0.01) and total periods (p < 0.05). The percentage of DW increased at 3% CRP (p < 0.05). The treatments increased the percentage of BW (p < 0.059) and, percentage of JL (p < 0.079) as well. The villus width and, crypt depth (CD) at 1% and 3% CRP and, villus surface at 3% reduced. The 3% CRP increased the villus length (VL) and villi number (p < 0.05) and, VL/CD (p < 0.01) and, villus surface area (p < 0.02). The percentage of leaf-like villi decreased in CRP treatments (p < 0.05). The number of goblet cells increased in CRP treatments (p < 0.01). In conclusion, chicory root powder can improve growth performance in broilers by enhancing food digestion and absorption through modification of jejunum histomorphometry.