Effect of Monovalent Copper Oxide and Potentiated Zinc Oxide on Growth Performance and Gut Morphology of Broiler Chickens Challenged with Coccidiosis.

An experiment was conducted to evaluate the effect of copper oxide (Cu2O) and potentiated zinc oxide (ZnO) on performance, intestinal morphology, oocyst excretion, coccidial lesion scores, and antioxidant properties in broilers during an Eimeria spp. challenge. A total of 288 1-day-old male broiler chickens (Ross 308) were divided into 18 treatments. Treatments included three levels of Cu (0, 15, or 150 mg/kg) from Cu2O and three levels of Zn (0, 80, or 160 mg/kg) from potentiated ZnO which were added to the basal diet and fed to broilers with or without challenge, using a completely randomized design in a factorial arrangement for 42 days. Live body weight, feed intake, mortality, and the cause of death were recorded weekly and histomorphology of jejunum was measured at the end of the experiment. Results showed that birds fed Cu and Zn linearly decreased (P < 0.0001) oocyst shedding. The number of excreted oocysts was reduced eight times in broilers fed a diet containing 150 mg/kg copper from Cu2O and 160 mg/kg zinc from potentiated ZnO, compared to the infected group without Cu and Zn supplementation (P < 0.0001). Microscopic features of both non-challenged and challenged broiler jejunum revealed significant improvement along with increased Cu2O and potentiated ZnO doses. Supplementation of Cu2O and potentiated ZnO decreased the jejunum structure damages and intestinal lesion score (P < 0.002). Eimeria caused a decrease (P < 0.006) in total antioxidant capacity. Superoxide dismutase increased by dietary zinc supplementation (P < 0.05). Results suggested that a combination of Cu2O and potentiated ZnO could exhibit efficient anticoccidial activity.

Comparison of absorption kinetics and utilisation of DL-methionine (DL-Met), Met-Met product (AQUAVI® Met-Met), and protein-bound methionine (PB-Met) by female broiler chickens.

1. Two experiments were conducted to determine the effects of different methionine (Met) sources regarding their absorption kinetics and utilisation in female single-meal-fed broiler chickens.2. A total of 340, one day old female Ross 308 broiler chickens were fed commercial starter and grower diets for 38 d. Birds were then allocated to treatment diets in two experiments as a completely randomised design with four replicates of five chicks per each until 60 d of age. In experiment 1, a 2 × 5 factorial design was used to investigate the effect of two sources (DL-Met and AQUAVI®Met-Met) and five equimolar levels (0.4, 0.8, 1.2, 1.6, and 2 g/kg) in the diet. In experiment 2, different proportions of protein-bound methionine (PB-Met) to DL-Met (0.4:1.6, 0.8:1.2, 1.2:0.8: 1.6:0.4, and 2:0 g/kg) were incorporated into a basal diet deficient in Met. During the experiment, chickens received 90 g of pelleted feed for a time period of 17 ± 2.5 min, once daily.3. The results indicated that chickens fed diets supplemented with DL-Met and Met-Met showed a rapid rise in plasma Met 1 h after feeding, with a sudden drop at 2 h after feeding. In contrast, chickens fed PB-Met substituted diets showed a gradual plasma peak at 1 and 2 h postprandial (P < 0.01). Plasma homocysteine (HCY) content increased to 34.38 and 40.43 µmol/l with DL-Met2.0 and Met-Met2.0 diets, while it decreased to 25.68 µmol/l with PB-Met2.0(P ≤ 0.01). Chickens that received the PB-Met2.0 diet had higher (P ≤ 0.01) protein utilisation (0.54 g/g) and lower excreta nitrogen content (4.04 g/100 g excreta), which demonstrated the benefits of feeding a protein-bound Met source. The efficiency of Met utilisation was 0.69 g/g in chickens fed PB-Met2.0 diet, but only 0.36 and 0.41 g/g in those fed DL-Met2.0 and Met-Met2.0 (P ≤ 0.01).4. The observed utilisation coefficient of DL-Met and Met-Met for single-meal meat-type chickens was lower than expected. The synchronisation of intestinal Met absorption maintained the efficiency of utilisation, which was related to the sources of added Met, with protein-bound Met showing the best utilisation and least excretion.

The effect of dietary coenzyme Q10 on plasma metabolites and hepatic gene expression in broiler breeder hens.

1. This study was performed to evaluate the effects of dietary supplementation of coenzyme Q10 (CoQ10) on laying rate, body weight, plasma metabolites and some liver gene expression in broiler breeder hens. 2. A total of 128 broiler breeder hens (Arbor Acres Plus, 47 weeks of age) were randomly distributed to four dietary groups supplemented with different levels of CoQ10 (0, 300, 600 or 900 mg/kg diet) with four replicates of eight hens each. During 47-54 weeks of age, laying rate, egg mass and body weight were recorded weekly. To assay plasma biochemical indicators, blood samples were collected at 54 weeks of age. At the end of the experiment, for evaluating the abdominal fat weight, liver weight and expression of the adiponectin and proliferator-activated receptor-α (PPAR-α) genes in the liver, eight hens per treatment were selected, weighed and humanely killed by decapitation. 3. Dietary supplementation of CoQ10 linearly decreased abdominal fat weight, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities by increased levels of CoQ10. The plasma levels of glucose, cholesterol and alkaline phosphatase (ALP) activity were quadratically decreased by increased levels of CoQ10. The best plasma levels of glucose, cholesterol and ALP activity were estimated at 562.5, 633.3 and 517.8 mg CoQ10/kg diet, respectively. Adiponectin and PPARα gene expression exhibited a linear increased by increased levels of CoQ10. 4. In conclusion, addition of CoQ10 to the diet influenced lipid metabolism and expression of the adiponectin and PPAR-α genes, which might be partially due to the improvement in mitochondrial metabolism and energy production. However, further studies are necessary to determine the effects of CoQ10 on these indicators in broiler breeder hens during ageing.

Changes in broiler breeder hen's immunity by zinc oxide and phytase.

BACKGROUND: The immune response of aged broiler breeder hens is influenced by many factors including obesity and aged lymphatic organs, but may improve by increasing the bioavailability of various nutrients such as zinc (Zn). Dietary supplementation of phytase can improve Zn availability in senescent broiler breeder hens. AIMS: The aim of this study was to investigate the effect of supplementary zinc oxide (ZnO) and phytase in a maize-soybean meal-based diet on immune responses of broiler breeder hens. METHODS: In a 2 × 4 factorial arrangement, a total of 128 hens were randomly assigned into eight groups. The birds received two levels of phytase (0 or 300 U/kg diet) and four levels of ZnO (30, 60, 90, and 120 mg/kg diet) for 13 successive wk (59-72 wk of age). RESULTS: Results showed that phytase supplementation significantly increased immunoglobulin M (IgM), cutaneous basophil hypersensitivity (CBH) responses, total number of leukocytes, percentage of lymphocytes, and heterophil to lymphocyte ratios. The percentage of basophils and monocytes, however, decreased with phytase supplementation. Supplementation of ZnO increased anti-sheep red blood cells (SRBC) antibody titer, IgM, CBH responses, the total number of leukocytes, and the percentage of lymphocytes. Dietary supplementation of ZnO decreased the percentage of heterophil, and heterophil to lymphocyte ratio. A significant interaction effect of phytase and ZnO was found on the total number of leukocytes and percentage of lymphocytes. CONCLUSION: Dietary supplementation of ZnO (90 mg/kg diet) and phytase had some positive effects on improving immune responses in broiler breeder hens.

Comparison of single- and multi-strain probiotics effects on broiler breeder performance, egg production, egg quality and hatchability.

1. This study was conducted to investigate the effect of multi-strain probiotic (containing Lactobacillus acidophilus 2.5 × 107 cfu/g, Lactobacillus casei 2.5 × 107 cfu/g, Bifidobacterium thermophilum 2.5 × 107 cfu/g and Enterococcus faecium 2.5 × 107 cfu/g) and single-strain probiotic (Pediococcus acidilactici 1 × 1010 cfu/g) on broiler breeder performance and gastrointestinal health. 2. A completely randomised trial was conducted using 300 broiler breeder hens (Ross 308) aged 51 weeks old which were randomly allocated to 1 of 5 dietary treatments with 6 replicates per treatment in a 10 week trial. Treatments included (1) the basal diet a negative control, (2) basal diet supplemented with 0.1 g/kg multi-strain probiotic (MS), (3) basal diet supplemented with 0.1 g/kg single-strain probiotic (SS), (4) basal diet supplemented with 0.1 g/kg of both of probiotics (MS+ SS) and (5) positive control basal diet supplemented with 0.5 g/kg oxytetracycline antibiotic (OX). 3. Body weight, egg production, yolk weight, eggshell thickness and weight, Haugh unit, fertility and hatchability were determined. Results showed that dietary treatments had no significant effect on total hen house or total hatching egg production, egg weight, yolk colour index, shell weight, mortality, body weight, fertility, hatchability, oviduct and stroma weight or number of large and small yellow follicles (P > 0.05). None of the jejunum morphological parameters, apparent ileal digestibility of protein and ileal Lactobacillus population were influenced by supplemental probiotics (P > 0.05), although ileum Escherichia coli count was reduced by inclusion of dietary probiotics (P < 0.05). 4. It was concluded that although both probiotic treatments reduced coliforms, they did not improve broiler breeder performance or gastrointestinal tract (GIT) function.

Effect of feeding guanidinoacetic acid and L-arginine on the fertility rate and sperm penetration in the perivitelline layer of aged broiler breeder hens.

Two experiments were conducted to evaluate the effects of feeding guanidinoacetic acid (GAA) and L-arginine (ARG) on fertility and sperm penetration (SP) rate of broiler breeder hens. In the first experiment, a total of 200 broiler breeder hens (Ross 308) aged 53 weeks were randomly allotted to four dietary treatments (0, 0.6, 1.2 and 1.8 g GAA/kg diet) with five replicates of 10 birds each. In the second experiment, 320 broiler breeder hens (Ross 308) were used from 53 to 62 weeks of age in a 2 × 4 factorial arrangement (0 or 1.2 g GAA/kg diet along with 0, 3, 6 or 9 g ARG/kg diet). The hens received a diet containing 2800 kcal ME/kg and 14% CP. Sixteen sexually mature Ross 308 breeder roosters (34 weeks old) were used to artificially inseminate the hens. Fertility of the hens was determined in 61 and 62 weeks of age. The sperm penetration holes in the inner perivitelline layer (IPL) overlying the germinal disc were enumerated on days 3 and 7 following each insemination. Adding GAA to the breeder diet increased the number of SPs in the IPL and fertility in both experiments (p < 0.01). The interactive effect of ARG and GAA on the SP and fertility was significant. Supplementary ARG increased the SP rate in the IPL (p < 0.01). In conclusion, dietary supplementation of GAA and ARG might be potentially used to improve the fertility of broiler breeder hens at the later phase of the egg production period.

Arginine, soy isoflavone and hydroxypropylmethylcellulose have protective effects against obesity in broiler breeder hens fed on high-energy diets.

1. The present study was undertaken to determine the effects of arginine, soy isoflavone (ISF) and hydroxypropylmethylcellulose (HPMC) on obesity in broiler breeder hens. 2. A total of 320 Cobb 500 hens, 45 weeks of age, were assigned to 64 floor pens. The experiment was conducted as a completely randomised design in a factorial arrangement (2 × 2 × 2 × 2) with 4 replicates of 5 hens in each pen. Factors included two concentrations of HPMC (0 and 1%), two concentrations of arginine (8.4 and 12 g/kg), two concentrations of ISF (zero and three times more than that present in basal diets) and two contents of energy (11.7 and 14.6 MJ/kg). Performance criteria and blood characteristics of hens were measured during the experimental period. Expression of genes involved in lipid metabolism was determined in the liver at 55 weeks of age. 3. Hens given high-energy diets showed increased BW (body weight), ovary weight and abdominal fat pad and enhanced plasma glucose, triglyceride (TG), cholesterol, haemoglobin, haematocrit and low lymphocyte percentages. The expression of malic enzyme, peroxisome proliferator-activated receptor-α (PPARα), peroxisome proliferator-activated receptor-γ (PPARγ) and inducible nitric oxide (iNOS) increased and sterol regulatory element binding protein-1c (SREBP1c) decreased with increasing energy content of diets. Arginine addition decreased TG, cholesterol and A1-c haemoglobin concentration and increased PPARα, PPARγ and iNOS expression. Inclusion of ISF and HPMC decreased BW, egg weight, plasma TG, cholesterol and increased egg production and also enhanced PPARγ and iNOS expression. Significant interactions were observed between energy concentration and ISF and HPMC on BW. 4. The results of the current study revealed that ISF, HPMC and arginine have beneficial effects on controlling the metabolism of obese broiler breeder hens and using a mix of these products minimises the harmful effects of obesity.

Effects of wheat inclusion and xylanase supplementation of the diet on productive performance, nutrient retention, and endogenous intestinal enzyme activity of laying hens.

An experiment was conducted to study the effects of inclusion of a wheat cultivar (high in nonstarch polysaccharides) and xylanase supplementation of the diet on productive performance, pH of the gastrointestinal tract, nutrient retention, and intestinal enzyme activity of Hy-Line W-36 laying hens from 25 to 47 wk of age. The experiment was completely randomized with 8 treatments arranged factorially with 4 levels of wheat (0, 23, 46, and 69%) that corresponded to a dietary arabinoxylan content of 3.0, 3.3, 3.6, and 3.9%, with or without xylanase supplementation. Each treatment was replicated 5 times. For the entire experimental period, egg weight (P < 0.05) and egg mass (P < 0.01) were reduced and the feed conversion ratio was hindered (P < 0.05) with increased levels of wheat in the diet, but ADFI and egg production were not affected. Xylanase supplementation improved egg production (P < 0.05), egg mass (P < 0.01), and the feed conversion ratio (P < 0.01). Diet did not affect egg quality at any age, except for shell thickness at 47 wk that was improved with xylanase supplementation (P < 0.05). Digesta pH of the different organs of the gastrointestinal tract was not affected by wheat inclusion or xylanase supplementation. Ileal viscosity increased (P < 0.001) with wheat inclusion and decreased (P < 0.001) with xylanase supplementation at all ages. Fat digestibility (P < 0.001) decreased with increased levels of wheat but AME(n) content of the diets (P < 0.05) and nitrogen retention were not affected. Wheat inclusion increased (P < 0.001) amylase (33 wk), lipase (33 wk), and aminopeptidase (47 wk) activity in the duodenum as well as lipase activity in the jejunum at 47 wk of age. However, xylanase supplementation did not affect the activity of any of the enzymes studied. It is concluded that most of the negative effects of wheat inclusion in the diet were reduced or even disappeared with xylanase supplementation. Wheat with a high nonstarch polysaccharide content (Pishtaz cultivar) can be used at levels of up to 69% in laying-hen diets without negatively affecting bird performance, provided that feeds are supplemented with xylanase.

Black cumin seeds, Artemisia leaves (Artemisia sieberi), and Camellia L. plant extract as phytogenic products in broiler diets and their effects on performance, blood constituents, immunity, and cecal microbial population.

Two experiments were conducted to evaluate the effects of using black cumin seeds (BCS), Artemisia leaves (AL), and Camellia L. plant extract (CLE) in the diets of broiler chicks. Experiment 1 was conducted as a completely randomized design in a factorial arrangement (2 × 2) with 8 replicates of 4 chicks in each battery cage. Factors included 2 levels of BCS and AL (0 and 1%). Experiment 2 was conducted as a completely randomized design with 4 treatments (control, 0.3 and 0.5 g/kg of CLE, and 0.5 g/kg of mannanoligosaccharide) of 8 replicates and 4 chicks in each. Body weight and cumulative feed intake were measured at 21, 35, and 42 d of age. Antibody response against SRBC was measured on d 28 and 42. Blood characteristics, relative weight and length of different parts of the carcass, gastrointestinal pH, villi length, and crypt depth were measured at 42 d of age. Artemisia addition did not affect BW and feed conversion ratio (FCR) but decreased feed intake significantly up to 21 d of age (P ≤ 0.01). Black cumin significantly increased BW (P ≤ 0.05) at 21 and 42 d of age and decreased FCR throughout the experimental period (P ≤ 0.01). Artemisia significantly increased monocytes but had no effect on gastrointestinal pH, antibody response, and relative weight and length of different parts of the carcass. Black cumin increased red blood cells, hematocrit, hemoglobin, gizzard relative weight, and pH but decreased antibody response and monocytes percentage (P ≤ 0.01). Artemisia did not affect plasma lipid profile but decreased coliform and Escherichia coli populations of ceca significantly (P ≤ 0.01 and P ≤ 0.05, respectively). Addition of 0.5 g/kg of CLE decreased BW, feed intake, and FCR throughout the experiment (P ≤ 0.01). Camellia increased gizzard and proventriculus pH, villi length, and crypt depth (P ≤ 0.01) but decreased primary antibody response, total white blood cell count, and cholesterol concentration (P ≤ 0.05). The results of this experiment showed that using BCS alone or mixed with AL improved broiler health and performance but CLE negatively affected broiler BW and feed intake and is not a good alternative to commercial mannanoligosaccharide.

The effect of dietary n-6:n-3 ratio and sex on broiler breeder immunity.

A study was conducted with male and female adult broiler breeders to determine the effect of feeding a fish oil supplement on selected immune activities. The fish oil was added to the diet such that the n-6:n-3 ratios could meet certain levels. Four hundred Ross 308 broiler breeder hens and 48 Ross 308 broiler breeder roosters at 30 wk of age were randomly assigned to diets containing 3.5% fat with n-6:n-3 ratios of 4, 6, 8, and 16. As a measure of cell-mediated immunity, thickness of the toe web was measured at 4, 8, 24, and 48 h after injection of phytohemagglutinin-P (PHA-P) at 32 wk of age. Total antibodies were quantified 6 and 9 d after the injection of SRBC at 33 wk of age. Blood lymphocyte proliferation was assayed after in vitro stimulation with PHA-P at 34 wk of age. The fatty acid profile of the spleen was determined in roosters. The effects of dietary n-6:n-3 ratios on total antibodies and in vitro lymphocyte proliferation were not significant (P > 0.05). However, the birds fed diets containing an n-6:n-3 ratio of 8 showed the greatest toe web thickness (P < 0.05). Total antibodies in hens at 9 d after SRBC injection were significantly greater than those of roosters. Conversely, toe web thickness in roosters was greater than that of hens (P < 0.05). Although the increase in the dietary n-6:n-3 ratio of polyunsaturated fatty acids significantly decreased the concentrations of eicosapentaenoic acid, docosahexaenoic acid, total n-3 (P < 0.05), linoleic acid, arachidonic acid, and total n-6, the n-6:n-3 fatty acid ratios of the entire spleen were significantly increased (P < 0.05). Results indicated that under the conditions of this study, the n-6:n-3 ratios seemed to influence the toe web response to PHA-P, but not the antibody response or the cell proliferation response in vitro.

Impact of dietary crude protein and amino acids status on performance and some excreta characteristics of broiler chicks during 10-28 days of age.

A study was conducted in a completely randomised design to evaluate the effects of providing almost all important essential amino acids (EAA) in low-crude protein (CP) diets equal to that of higher CP diets in broiler chickens. Also the effects of additional mixture of glycine (Gly) and glutamic acid (Glu) or supplementation of excess EAA to low-CP diets on the live performance and excreta characteristics including pH, moisture, nitrogen, uric acid and ammonia concentration were measured to ascertain the optimum CP concentration for the maximum performance and reduced excreta ammonia concentration. Male, broiler chickens growing from 10 to 28 days of age were fed eight experimental diets. Reducing dietary CP below 19% negatively affected performance. Adding the Gly and Glu mixtures to 17% CP diets improved live performance. Reducing CP to 19% with a normal amino acids status declined N, ammonia, uric acid, moisture and pH of excreta significantly. These findings suggest that diminishing dietary CP from 23% to 19% while maintaining adequate EAA levels during 10-28 days of age results in not only a significant decline in N emission, but also a probable reduction in the NH(3) volatilisation because of reduction in pH and moisture. Contrary to expectations, reduction of dietary CP below the minimum level (19%) resulted in more ammonia. All these factors may improve on litter and air quality within the housing facility and reduce the ventilation rate required to emit the elevated ammonia gas concentrations.

Effects of fortifying low crude protein diet with crystalline amino acids on performance, blood ammonia level, and excreta characteristics of broiler chicks.

A study was conducted in a completely randomized design to evaluate the performance, excreta characteristics, and some blood nitrogen metabolite concentrations of 28-d-old male broilers fed 4 experimental diets in which CP was decreased in a stepwise manner from 23 to 17%. The other 4 diets were formulated to have 19 and 17% CP, in which 2 of them contained an additional 10% of particular essential amino acids (EAA) and 2 were supplemented with Gly and Glu. Ileal digestible quantities of all EAA were almost equal in the diets, and total amount of each EAA was maintained at or above NRC requirements. Decreasing dietary CP below 19% depressed performance and appetite and increased fat deposition in the whole body and abdominal cavity significantly. Adding the Gly and Glu mixtures to low-CP diets improved performance and decreased fat deposition. Uric acid, moisture, and acidity of excreta were decreased by reduction of dietary CP; excretory ammonia level was increased in 17% CP diets. Blood ammonia level was increased and plasma uric acid was decreased with reduction of CP to 17%. Supplementing Gly and Glu increased plasma and excretory uric acid level in spite of decreasing blood ammonia concentration. The aminostatic hypothesis cannot explain the sharp reduction in appetite in this experiment, because alteration of dietary CP had no significant influence on most plasma free amino acid levels. Therefore, reduction of CP to 19% not only does not impair performance but also decrease nitrogen, ammonia, and pH of excreta that may improve upon litter and air quality. Adding large amounts of crystalline EAA to diets with low intact CP increased blood and excretory ammonia concentration, which due to its negative effects on tissue metabolism may be the main cause of retarded growth and appetite in decreased CP diets below 19%.