Showing papers in "British Poultry Science in 2007"
TL;DR: Generally, dietary thyme oil or yarrow herb inclusion had the most positive effects on chick performance, while oregano herb and yarrow oil were the poorest supplements.
Abstract: 1. The effect of the dietary inclusion of 5 culinary herbs or their essential oils on the growth, digestibility and intestinal microflora status in female broiler chicks was assessed. From 7 to 28 d of age, either a basal control diet without supplement was given or one of 10 others, consisting of the basal diet with either 10 g/kg herb (thyme, oregano, marjoram, rosemary or yarrow) or 1 g/kg of essential oil. 2. Body mass (BM) and feed consumption (AFC) were measured on a weekly basis and used to calculate chick performance. Total viable counts of lactic acid bacteria, coliforms, anaerobes and Clostridium perfringens were determined at 25 d. Apparent nutrient digestibilities were calculated from the measured values for gross energy, nitrogen (N), dry matter (DM) and organic matter, and sialic acid concentration was also measured. 3. Generally, dietary thyme oil or yarrow herb inclusion had the most positive effects on chick performance, while oregano herb and yarrow oil were the poorest supplements. Only...
510 citations
TL;DR: Understanding the nuances of nutrition and immunity is important for optimising bird health and productivity, and will be an important contributor towards fulfilling the consumer's conflicting demands for more natural production and better animal welfare.
Abstract: 1. Infectious diseases reduce productivity and diminish animal welfare. 2. Appropriate nutrition may aid in minimising the incidence of diseases by enhancing immunity. 3. An understanding of the pressures imposed by evolution that underlie poultry nutrition as well as those which underlie immunity provides focus to the field of nutritional immunology. Additional understanding is provided by knowing the specific cellular mechanisms by which diet affects immunity, and how these mechanisms pertain to specific nutrients and pathogens. 4. These approaches indicate that higher inclusion rates of all nutrients are not always better and that the traditional ideas of adding a surfeit of specific nutrients to improve immunity does not usually serve us well. 5. Understanding the nuances of nutrition and immunity is important for optimising bird health and productivity, and will be an important contributor towards fulfilling the consumer's conflicting demands for more natural production and better animal welfare.
289 citations
TL;DR: It was concluded that high litter moisture alone was sufficient to cause foot pad dermatitis in young turkeys and that footpad dermatitis should be minimised by the maintenance of dry litter.
Abstract: 1. Four randomised block experiments were conducted to determine the role of litter moisture, excreta and alternative bedding materials on the development of footpad dermatitis in growing turkeys. 2. Adding water to the litter increased external and histopathological scores independently of the presence of excreta. Fully developed lesions were induced by the application of water to dry litter in 2 to 4 d. 3. Footpad lesions were associated with discomfort during walking in one experiment and body weight was lower in birds on wet compared with dry litter. 4. Footpad lesions had virtually healed 15 d after transfer of the turkeys from wet to dry litter although histopathology assessment showed some residual tissue repair. 5. Long barley straw was associated with high footpad scores on wet and dry treatments. The footpad scores for turkeys on reprocessed cardboard chips were similarly high whereas scores were similar on paper litter and wood shavings whether dry or wet. 6. It was concluded that high litter moisture alone was sufficient to cause footpad dermatitis in young turkeys and that footpad dermatitis should be minimised by the maintenance of dry litter.
178 citations
TL;DR: Reduced HBS was also associated with increased final litter depth, younger slaughter age and an increased percentage of dietary wheat, and an effect of hatchery was also identified.
Abstract: 1. Standardised data on flock husbandry were recorded on 149 broiler farms during the 4 d prior to slaughter. 2. Birds were examined at the slaughterhouse for contact dermatitis lesions. Foot pad dermatitis score (FPDS) and hock burn score (HBS) were measured on five point scales. Carcase rejection data were also collected. 3. The mean percentage of birds in each flock with: moderate or severe foot lesions was 11.1% (range 0-71.5%); moderate or severe hock burn was 1.3% (range 0-33.3%); and, breast burn was 0.02%. 4. A general linear model was developed to examine factors associated with mean flock FPDS. Assuming a linear relationship, within the range of data collected and with all other factors remaining the same, every 1% increase in the proportion of Genotype A birds in the flock was associated with an increase in mean FPDS of 0.003, every one-point increase in litter score was associated with a 0.326 increase in mean FPDS and every one-point increase in flock mean HBS was associated with a 0.411 increase in mean FPDS. Flock mean FPDS was associated with feed supplier and was higher in winter. 5. The general linear model developed for flock mean HBS, found that every one-point increase in mean FPDS increased mean HBS by 0.090, every one-point increase in litter score increased HBS by 0.119 and, every 1% increase in small/emaciated birds decreased mean HBS by 0.333. Reduced HBS was also associated with increased final litter depth, younger slaughter age and an increased percentage of dietary wheat. For every 1% increase in Genotype A birds, a decrease in flock mean HBS of 0.003 would be expected. 6. An effect of hatchery was also identified.
162 citations
TL;DR: Access to different types of foraging material such as silages and carrots improved animal welfare and decreased damaging pecking in general, reduced severe feather pecking behaviour and improved the quality of the plumage at 54 weeks of age.
Abstract: 1. An experiment was carried out to examine the suitability of using maize silage, barley-pea silage and carrots as foraging materials for egg-laying hens. Production performance, nutrient digestibility, gastrointestinal characteristics, including the composition of the intestinal microflora as well as feather pecking behaviour were the outcome variables. 2. The protein content of the foraging material (g/kg DM) was on average 69 g in carrots, 94 g in maize silage and 125 g in barley-pea silage. The starch content was highest in the maize silage (312 g/kg DM), and the content of non-starch polysaccharides (NSP) varied from 196 to 390 g/kg, being lowest in carrots. Sugars were just traceable in the silages, whereas carrots contained on average 496 g/kg DM. 3. Egg production was highest in hens fed either carrots or maize silage, whereas hens fed barley-pea silage produced less (219 vs. 208). Although the consumption of foraging material was high (33, 35 and 48% of the total feed intake on 'as fed' basis for maize silage, barley-pea silage and carrots, respectively) only a minor effect on nitrogen corrected apparent metabolisable energy (AME(n)) and apparent digestibility was seen. At 53 weeks of age, hens fed maize silage had AME(n) and apparent digestibility values close to the control group (12.61 and 12.82, respectively), whereas access to barley-pea silage and carrots resulted in slightly lower values (12.36 and 12.42, respectively). Mortality was reduced dramatically in the three groups given supplements (0.5 to 2.5%) compared to the control group (15.2%). 4. Hens receiving silage had greater relative gizzard weights than the control or carrot-fed groups. At 53 weeks of age, the gizzard-content pH of hens receiving silage was about 0.7 to 0.9 units lower than that of the control or carrot-fed hens. Hens fed both types of silage had higher concentrations of lactic acid (15.6 vs. 3.2 micromoles/g) and acetic acid (3.6 vs. 6.1 micromoles/g) in the gizzard contents than the other two groups. The dietary supplements had a minor effect on the composition of the intestinal microflora of the hens. 5. Access to all three types of supplements decreased damaging pecking in general (to feathers as well as skin/cloaca), reduced severe feather pecking behaviour and improved the quality of the plumage at 54 weeks of age. 6. In conclusion, access to different types of foraging material such as silages and carrots improved animal welfare.
104 citations
TL;DR: Age at sexual maturity was affected adversely by dietary AFB1, and various adverse changes in liver, kidney, heart, ovaries and bursa of Fabricius in AFB1-fed groups were showed.
Abstract: 1. An experiment on 1-week-old, White Leghorn female chicks was conducted to study the effect of aflatoxin AFB1 on weight gain, feed intake, feed gain ratio, age at sexual maturity, production and quality of eggs, retention of nutrients, pathoanatomical and histopathological parameters, and also on AFB1 residues in eggs and muscles of hens. The chicks were assigned to 4 dietary treatments: D1 (without AFB1), D2 (2.50 mg/kg AFB1), D3 (3.13 mg/kg AFB1), D4 (3.91 mg/kg AFB1) up to the age of 40 weeks. 2. At the end of the experiment, the mean body weight gain and feed intake were significantly lower in all aflatoxin-fed groups compared to control. The feed gain ratios were noted as 13.41, 13.59, 13.82 and 14.71, with the group fed the highest concentration of AFB1 showing a significantly poorer ratio than other groups. 3. Age at sexual maturity was also affected adversely by dietary AFB1: 193 d for D4 as compared to as early as 148 d for D1. Hen-d egg production was recorded as 96.92, 74.67, 65.98 and 50.75 in D1, D2, D3 and D4, respectively. 4. Average egg weights at the end of the experiment were 57.77, 57.49, 57.54 and 54.66 for D1, D2, D3 and D4, respectively. Shape index was significantly lower in D4 as compared to control. Contrary to this, albumen index was significantly higher in D4 as compared to D1. The values of yolk indices and eggshell thickness did not differ significantly among treatment groups. However, colour of yolk was reduced in all aflatoxin-fed groups compared to control. 5. Retentions of dry matter, crude protein, ether extract, calcium and metabolisable energy were adversely affected at various levels of AFB1 compared to control. 6. Pathoanatomical and histopathological studies showed various adverse changes in liver, kidney, heart, ovaries and bursa of Fabricius in AFB1-fed groups. 7. Different amounts of aflatoxin residues were detected in eggs and breast muscles of hen in all AFB1-fed groups.
92 citations
TL;DR: A mechanistic, stochastic population model for layers may be used to verify that these functions correctly reflect the proportional changes in the egg components with advancing hen age and at a given age, over a range of egg weights.
Abstract: 1. As hens age, egg weight increases but the eggs contain proportionally more yolk and less albumen and shell. However, at a given age, larger eggs contain proportionally more albumen. When modelling the nutrient requirements of the hen over a production cycle, based on the daily outputs of each nutrient, egg weight needs to be predicted as the sum of the three components, since each has a unique chemical composition, and these proportional changes will therefore influence the nutrient requirements of the hen. 2. Yolk weight is related to hen age and may be calculated using a logistic or Gompertz function. Allometric functions are used to predict albumen weight from yolk weight and shell weight from the weight of the egg contents. 3. A mechanistic, stochastic population model for layers may be used to verify that these functions correctly reflect the proportional changes in the egg components with advancing hen age and at a given age, over a range of egg weights. 4. The various parameters used in the equations need to be defined for the available genotypes.
83 citations
TL;DR: It is concluded that a single dose of Lactobacillus fermentum or LactOBacillus spp.
Abstract: 1. Live body weight gain (WG) and food conversion efficiency (FCE) were measured over a 4-week period in chicks (female, Kabir strain), inoculated intragastrically at one week of age with either a single dose (1 ml) of 10(7) live bacterial cells of Lactobacillus fermentum (LBF) or a strain of Lactobacillus spp. (LB), named Autruche 4 (A4), suspended in 1 ml of phosphate-buffered saline (PBS, pH 7.0); controls (n = 10) were inoculated only with PBS. The same commercial chicken feed was used throughout the 4-week experiment. 2. Compared with the control group, WG to 8 and 21 d, and also liver weight, were significantly greater in LBF and A4 treatments and FCE improved in both of the experimental groups. Compared with the A4 treatment group, WG was significantly higher and FCE improved in the LBF-treated group. The effects of A4 treatment on chicks were similar to those in an earlier pilot experiment using the same methodology but with 1-week-old female chicks (Kabir) inoculated with either the A4 strain or strain of LB named Autruche 5. 3. It is concluded that a single dose of Lactobacillus fermentum or Lactobacillus spp. (Autruche 4) administered intragastrically improves WG and FCE of broiler chicks.
83 citations
TL;DR: This first holo-analysis of the efficacy in broiler nutrition of the saccharide product, Bio-Mos® (BM), is part of a comprehensive empirical modelling research programme quantifying and comparing the efficacies and future research needs of the diverse candidates offered as replacements for antibiotics.
Abstract: 1. This first holo-analysis of the efficacy in broiler nutrition of the saccharide product, Bio-Mos(R) (BM), is part of a comprehensive empirical modelling research programme quantifying and comparing the efficacies and future research needs of the diverse candidates offered as replacements for antibiotics. 2. The data used are from 32 publications with broiler performance data from a world-wide literature collection of 124 (1997-2003) on the use of BM as a broiler feed additive. It contains the results of 82 negatively controlled feeding tests from 21 countries using a total of 85 142 broilers, averaging 401 per treatment. 3. The 82 feed intake, liveweight gain, feed conversion ratio and 44 mortality responses to BM average -12.2 g, 27.6 g, -0.0391 and 0.0311%, respectively, with coefficients of variation of 828, 227, 192 and 8392%. Respective beneficial response frequencies for gain, conversion and mortality are 65, 70 (52% jointly) and 52%. 4. Holo-analytical multiple regression models were elaborated for the effects of BM on feed intake, liveweight gain, feed conversion ratio and mortality, using conventional P or=0.10 out and less stringent P or=0.34 out partial regression coefficient standards, with and without>or=3xroot mean square error outliers, in order to quantify the influences of negative control performance, test duration, BM dosage, cage housing, processed feed, antibiotic feed, year of test and USA test. To date they account for only 5-36% of response variations, due primarily to 52 of the 82 tests having no reported feed formulations. 5. These exploratory models confirm beneficial responses to BM for current broiler performance levels. They also indicate a need to clarify BM dose-response relationships in order to maximise efficient use in praxis and to facilitate cogent comparisons with other pronutrients, including other saccharide products.
82 citations
TL;DR: It could be concluded that supplementation of the wheat-based broiler ration with virginiamycin had significant positive effects on gastrointestinal tract characteristics for absorption.
Abstract: The aim of the present study was to compare wheat-based diets supplemented with arabinoxylanase, bile acid and virginiamycin with a maize-based diet in their effects on the performance of broilers. 2. The diets were fed to 5 groups of broilers. Group A received a maize-based diet (control), and groups B, C, D and E were fed on wheat-based diets. Diets C, D and E were supplemented with arabinoxylanase (150 mg/kg), bile acid (500 mg/kg) and virginiamycin (200 mg/kg), respectively. 3. A total of 450 1-d-old Ross 385 chicks were randomly divided into 5 groups, each with three pens as replicates (30 birds per pen). The experimental diets were given for 18 d. On d 18, three chickens from each group were slaughtered by cervical dislocation and the liver weight, and duodenal, jejunal and ileal lengths were measured for length and width of the villi and the height of crypts. 4. Arabinoxylanase, bile acid and virginiamycin supplementation significantly increased feed intake and daily gain but had no significant effect on feed conversion ratio. The liver weight was significantly greater in virginiamycin supplemented chicks as compared with those on the diet containing bile acid. 5. Virginiamycin inclusion increased full and empty caeca weight significantly compared with groups A and D. Group A had the lightest caeca. Significant effects of diets were observed on duodenal, ileal and intestinal length, but jejunal length was not affected by diet. The heights of duodenal and ileal, but not jejunal, villi were significantly affected by the treatments. The lengths of villi in groups B and E were significantly higher than other groups. The mean height of ileal villi in group A was significantly higher than in groups receiving the wheat-based diets. The mean width of duodenal and ileal villi was significantly affected by the ration. The height of crypts in group B was significantly higher than in group E. 6. It could be concluded that supplementation of the wheat-based broiler ration with virginiamycin had significant positive effects on gastrointestinal tract characteristics for absorption. Supplementation with bile acid reduced the weight of liver and caeca and the length of duodenum, jejunum, ileum and in small intestine and the height and width of villi.
74 citations
TL;DR: It is concluded that supplementation with an enzyme preparation (xylanase), which hydrolyses non-starch polysaccharides can improve growth and feed conversion efficiency in cockerels fed on wheat-based diets.
Abstract: 1. The xylanase product used in this study was derived from a genetically modified isolate of Aspergillus niger. Two trials were conducted to investigate the effects of xylanase supplementation on growth, digestion, circulating hormone and metabolite levels, immune parameters and composition of the gut microflora in cockerels fed on wheat-based diets. 2. The experimental diets consisted of a wheat-based control diet supplemented with 0 or 0.1% enzyme preparation. The diets were fed between 7 and 21 d of age. 3. Enzyme supplementation improved growth and feed conversion efficiency. The addition of enzyme to wheat-based diet increased the apparent total digestibility of dry matter (DM), crude protein and fat. 4. Enzyme supplementation reduced the relative weight of digestive organs to a certain extent, but there was no significant difference. Enzyme supplementation reduced digesta viscosity in the jejunum. There was no significant difference between the two experimental groups in counts of lactobacillus and coliform bacteria in the caeca. 5. Enzyme supplementation increased the concentration of blood thyroxine (T(4)), insulin-like growth factor I (IGF-I) and insulin, reduced the concentrations of blood uric acid, but had no significant effect on the concentrations of blood glucose and triiodothyronine (T(3)). 6. Enzyme supplementation increased the relative weight of spleen of cockerels, serum antibody titres to Newcastle disease virus (NDV), lymphocyte proliferation in response to phytohaemagglutinin (PHA) and the natural killer (NK) cell activity. 7. It is concluded that supplementation with an enzyme preparation (xylanase), which hydrolyses non-starch polysaccharides can improve growth in cockerels fed on wheat-based diets. This improvement is achieved through enzyme effects on digestion, absorption, metabolism and immunity of cockerels.
TL;DR: In the mixtures 29:71 LF:LG and 32:68 LF:oyster shell, there were significantly greater eggshell quality, eggshell weight, egg shell thickness and eggshell strength, and the midnight feeding had no significant effect on egg shell quality.
Abstract: 1. Four different sources of calcium in isonitrogenous and isoenergeric diets were fed to laying hens for 2 weeks when they were 56 and 57 weeks old. The calcium source blends were as follows: 29% fine limestone (LF)+71% large limestone (LG), 32% LF+68% eggshell, 32% LF+68% oyster shell, 50% LF+50% LG. The contents of these blends of calcium in the diets were as follows: 103.3, 93.3, 93.3 and 93.3 g/kg, respectively. 2. The coefficients of calcium retention were significantly higher in 50:50 LF:LG (0.578) and 32:68 LF:eggshell (0.576). The midnight feeding significantly improved the coefficient of calcium retention in all mixtures except 50:50 LF:LG. 3. In the mixtures 29:71 LF:LG and 32:68 LF:oyster shell, there were significantly greater eggshell quality, eggshell weight, eggshell thickness and eggshell strength. Midnight feeding had no significant effect on eggshell quality. 4. In the ration with oyster shells, 96.5% of the retained calcium was deposited in the eggshell, but in rations 32:68 LF:eggshell and 50:50 LF:LG the utilisation was only 73.9 and 78.6%, respectively. 5. To ensure good quality eggshells in the last third of production, the recommendation for calcium is 4.1 g/kg (900 g/kg dry matter, feed intake 110 g/d). As a source of calcium in this stage of production, a feed mixture containing two-thirds large particles should be used (limestone grit or oyster shell).
TL;DR: It is indicated that feeding a diet supplemented with MNB during the first two weeks after hatching reduced susceptibility to SE infection and increased IgA production and improved SE clearance by acting as immunomodulatory agents that prevented intestinal pathology.
Abstract: 1. This study investigated the effects of beta1-4 Mannobiose (MNB)-supplemented feeds on the kinetics of Salmonella enterica serovar Enteritidis (SE) in broilers and the ensuing histopathological changes. D-Mannose (MAN) was used for comparison. The diets supplemented with MNB or MAN were fed during the first two weeks after hatching to investigate any protection against SE infection in growing birds and any immunomodulatory functions in the gut. 2. MNB-supplementation reduced SE organ colonisation, caecal carriage and faecal shedding in a time-dependent manner. The high concentrations and persistency of the SE-specific IgA response in those birds given rations supplemented with MNB or MAN were associated with a decline in SE shedding and caecal carriage in the later stages of infection. MNB was more effective against SE infection than MAN. 3. Histological examination of the caecal wall and caecal tonsils at 23 d post-infection indicated a lesser degree of intestinal pathology. An increased number of intra-epithelial mononuclear cells (mature lymphocytes and macrophages) in the lining epithelium of birds fed on the diet supplemented with MNB was accompanied by an increased number of lamina propria cells. 4. The present study indicates that feeding a diet supplemented with MNB during the first two weeks after hatching reduced susceptibility to SE infection. Supplementing the diet with MNB or MAN increased IgA production and improved SE clearance by acting as immunomodulatory agents that prevented intestinal pathology. Feeding a MNB-supplemented diet to broilers could be used as an alternative to antibiotics, because it has no adverse effects on mortality or weight gain.
TL;DR: These findings indicate the ability of modern poultry to digest chitin but suggest that the ingestion of insects is not an important source of nutrients, at least from the exoskeleton.
Abstract: 1. Little is known about the ability of farmed poultry to digest chitin and derive nutrients from the ingestion of insects. 2. Commercial chitin derived from crustacean shell waste was found to contain 373 g crude protein, 265 g ash, 23·5 g ether extract, 130 g calcium and 16·4 g phosphorus per kg, on an air-dry basis. 3. It was included in diets at 0, 25, 50 and 75 g chitin per kg and fed to 320 1-d-old broiler males, over a 21-d period. There were no statistically significant treatment effects on weight gain or feed efficiency. Apparent digestibility of chitin protein was 0·48, 0·50 and 0·45, at the 25, 50 and 75 g per kg inclusions, respectively. Mean AME and AMEN values of chitin were determined as 8·97 and 8·86 MJ/kg. 4. In a subsequent study, mean TME and TMEN values of chitin were determined to be 8·23 and 8·21 MJ per kg, respectively. Addition of chitinase to the diet increased TME and TMEN of chitin to 8·81 and 8·79 MJ per kg, respectively (P < 0·05). True digestibility of chitin protein was dete...
TL;DR: Combination of phytases acting in the gizzard with phytaseacting in the intestine seems to be a promising way to further improving in vivo efficacy ofphytases in poultry.
Abstract: 1. Three bacterial phytases derived from Bacillus, Escherichia coli or Klebsiella were compared with a phytase derived from Aspergillus niger in vitro and in vivo. 2. The in vitro results indicated that Aspergillus, E. coli and Klebsiella phytase displayed their activity optima in an acid pH range while Bacillus phytase did so in neutral pH. 3. The trials also revealed that only Bacillus phytase is more resistant to heat treatments, while E. coli and Klebsiella phytases are more stable against proteolytic inactivation. 4. In vivo phytases derived from Aspergillus, Bacillus, E. coli, Klebsiella or a combination of Bacillus and E. coli improved the utilisation of phosphorus (P balance) significantly to 0·54, 0·54, 0·55, 0·55 or 0·58, respectively, compared to 0·42 in the negative control. 5. The phytases used in this study seemed to be equally effective in improving P utilisation regardless of proposed intestinal site of activity. Combination of phytases acting in the gizzard with phytases acting in the int...
TL;DR: An interactive effect of phytase and Bioplex Zn® on feed intake, weight gain, tibia Zn concentration and tibia ash weight was found.
Abstract: 1. The purpose of this study was to investigate the effects of Bioplex Zn (a chelated zinc proteinate) and phytase supplementation in a maize-soybean meal diet on the performance and tissue zinc (Zn) content of broiler chicks. Treatment structure consisted of a 2 x 6 factorial arrangement with two inclusions of phytase (0 or 500 PU/kg) and 6 of Bioplex Zn providing 0, 2, 4, 8, 16 and 32 mg Zn/kg diet. A total of 864 chicks were randomly assigned to each of 12 dietary treatments with 6 replicate cages of 12 chicks. 2. Dietary inclusion of phytase increased feed intake, weight gain, plasma Zn content, tibia Zn content, tibia and ash weight. 3. Dietary supplementation of Bioplex Zn linearly increased feed intake, weight gain, gain to feed ratio, plasma Zn concentration, liver Zn concentration, tibia Zn content, tibia and ash weight. 4. An interactive effect of phytase and Bioplex Zn on feed intake, weight gain, tibia Zn concentration and tibia ash weight was found. 5. One slope, straight broken-line analysis of weight gain regressed on the supplemental Zn level provided as Bioplex Zn indicated that 12 mg/kg supplemental Zn without phytase and 7.4 mg/kg supplemental Zn with phytase were required for the optimal weight gain of chicks.
TL;DR: The results suggest that processing of FFSB in order to reduce TIA levels below 4 mg/g may provide significant benefits for broiler chicks.
Abstract: 1. Increasing proportions of soybeans in poultry diets have highlighted the importance of correct processing to inactivate the anti-nutritional factors present whilst maintaining protein quality. 2. Ground full fat soybeans (FFSB) were extruded using a Clextral laboratory model twin-screw extruder with 0·75 l/h of water and end barrel temperatures of 90, 110, 130 and 160°C resulting in trypsin inhibitor activities (TIA) of 14·8, 9·6, 4·5 and 1·9 mg/g sample. 3. The 4 extrudates were used at three different inclusion levels: 200, 400 and 600 g/kg semi-synthetic diet and fed to male Ross broiler chicks from d 19 to d 26. Digesta samples were taken for measurement of coefficient of ileal apparent amino acid digestibility (CIAD) and both pancreas and whole bird weights were measured. 4. Concentration of ileal apparent digestible lysine was increased from 10·53 to 17·63 g/kg FFSB by increasing extrusion temperature from 90 to 160°C. CIAD of lysine was also improved from 0·58 to 0·86. Other amino acids showed s...
TL;DR: It appears reasonable to assume that the derived benefit is a result of the organism surviving, and the associated performance of some function in the intestinal tract which benefits gut health.
Abstract: 1. This study was conducted to evaluate the feasibility of using a transformed Lactobacillus reuteri Pg4 strain harbouring a rumen fungal xylanase gene as a probiotic supplement in a wheat-based poultry diet. 2. A total of 400 broiler chicks was allocated to two treatment groups with or without supplementation with 10(6) colony forming units (cfu)/g of transformed L. reuteri Pg4 in a wheat-based regimen to investigate the performance, intestinal microflora populations, digesta viscosity and excreta ammonia concentrations in these broiler chickens. 3. Supplementation of the wheat-based diet with transformed L. reuteri Pg4 decreased intestinal viscosity, caecal coliform population, and increased body weight gain and ileal villus height and crypt depth from 0 to 21 d of age. It also decreased excreta ammonia concentrations, and increased the caecal total volatile fatty acid (VFA) and lactic acid concentrations from 0 to 21 d and 22 to 37 d of age. 4. Further, it was demonstrated that 40% of the Lactobacillus cells randomly isolated from the digesta of the ileum and caecum of the supplemented group possessed xylanase secretion capability. 5. It appears reasonable to assume, therefore, that the derived benefit is a result of the organism surviving, and the associated performance of some function in the intestinal tract which benefits gut health.
TL;DR: Comparing the effect of dietary supplementation with organic or inorganic selenium (Se) sources plus control amounts or large amounts of vitamin E (α-tocopherol acetate) in broilers raised at control or low temperatures indicates increased activity of birds’ antioxidant defence against suboptimal environments.
Abstract: 1. This study compared the effect of dietary supplementation with organic or inorganic selenium (Se) sources plus control amounts or large amounts of vitamin E (alpha-tocopherol acetate) in broilers raised at control (20 to 24 degrees C) or low (14.5 to 16.8 degrees C) temperatures after 2 weeks of age. 2. The following dietary treatments were used from one day old. Diet 1, the control diet, comprised a commercial diet containing 0.15 mg/kg inorganic Se and 50 mg vitamin E/kg feed. Diet 2 was the same as diet 1, supplemented with 0.15 mg/kg inorganic Se. Diet 3 was the same as diet 2 but was supplemented with 200 mg/kg vitamin E. Diet 4 was the same as diet 1, but inorganic Se was replaced with 0.30 mg/kg organic Se. Diet 5 was the same as diet 4, supplemented with 200 mg/kg vitamin E. 3. Low temperature reduced the growth rate of broilers; however, at 6 weeks, there were no differences in the body weights of birds fed on organic Se supplemented diets housed at low or control temperature. The feed conversion ratio was significantly affected by low temperature but not by diet. The heterophil/lymphocyte ratio was higher in chicks after one week in the cold, indicating mild stress. Blood triiodothyronine levels were significantly higher in birds after 1 and 4 weeks in the cold but thyroxin was not affected. 4. Organic Se supplementation increased relative lung weight at the control temperature, which might lead to greater respiratory capacity. Relative spleen weight significantly decreased in broilers fed diets supplemented with inorganic Se under cold conditions, a possible indication of chronic oxidative stress. 5. At the low temperature, supplementation with organic Se alone, or with inorganic Se and vitamin E increased glutathione peroxidase (GSHPx) activity and glutathione (GSH) concentration in the liver of broilers, which may indicate increased activity of birds' antioxidant defence against suboptimal environments.
TL;DR: Genetic parameters were estimated in a base population of a closed experimental strain of fowl subject to 8 successive generations of selection and the method of multi-traits restricted maximum likelihood with an animal model was used to estimate genetic parameters.
Abstract: 1. Genetic parameters were estimated in a base population of a closed experimental strain of fowl. Data were obtained on 21 245 Iranian native hens (breeding centre for Fars province) subject to 8 successive generations of selection. This population had been selected for body weight at 12 weeks of age (BW12) and egg number during the first 12 weeks of the laying period (EN), mean egg weight (EW) at weeks 28, 30 and 32, and age at sexual maturity (ASM). 2. The method of multi-traits restricted maximum likelihood with an animal model was used to estimate genetic parameters. Resulting heritabilities for BW12, EN, EW and ASM were 0.68 +/- 0.02, 0.40 +/- 0.02, 0.64 +/- 0.02 and 0.49 +/- 0.02, respectively. 3. Genetic correlations between BW12 and EN, EW and ASM were 0.11 +/- 0.33, 0.54 +/- 0.21 and -0.12 +/- 0.03, respectively. Genetic correlations between EN and EW and ASM were -0.09 +/- 0.03 and -0.85 +/- 0.01, respectively, while between EW and ASM, it was 0.05 +/- 0.03. 4. The overall predicted genetic gains, after 7 generations of selection, estimated by the regression coefficients of the breeding value on generation number were equal to 22.7, 0.17, 0.04 and -1.38, for BW12, EN, EW and ASM, respectively. 5. A pedigree file of 21 245 female and male birds was used to calculate inbreeding coefficients and their influence on production and reproduction traits. Average inbreeding coefficients for all birds, inbred birds, female birds and male birds were 0.048, 0.673, 0.055 and 0.047%, respectively. Regression coefficients of BW12, ASM, EN and EW on inbreeding coefficient for all birds were equal to 0.51 +/- 0.001, 0.31 +/- 0.003, -0.51 +/- 0.003 and 0.03 +/- 0.001, respectively.
TL;DR: Bone mineral density, serum OC, vitamin D, Ca, P levels and ALP activity were significantly improved by soy isoflavone supplementation in both the TN and HS groups in quail during the late laying period.
Abstract: 1. Soy isoflavones play a role in calcium and bone metabolism. Poor egg quality, skeletal abnormalities and architectural deterioration of bone tissue are common problems under hot climate conditions and with increased age in poultry. 2. In this study, we investigated the effects of soy isoflavone supplementation on egg production, egg quality, bone mineral density (BMD), levels of osteocalcin (OC), vitamin D, calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) activity in quail (Coturnix coturnix japonica) during the late laying period. 3. The birds (n = 180; 28 weeks old) were randomly assigned to 6 treatment groups consisting of 6 replicates of 5 birds each in a 2 x 3 factorial arrangement of treatments (temperatures, soy isoflavone concentration). Birds were kept in wire cages in a temperature-controlled room at either 22 degrees C (thermo-neutral, TN) or 34 degrees C (heat stress, HS) for 8 h/d (09:00 to 17:00 h; until the end of the study) and fed either on a basal (control) diet or on the basal diet supplemented with either 400 or 800 mg of soy isoflavones/kg of diet. 4. Heat exposure reduced feed intake, egg production, egg quality, BMD, OC, vitamin D, Ca, P and ALP when the basal diet was given. Feed intake, egg production and egg weight were not affected, while eggshell thickness and eggshell weight increased in soy isoflavone-supplemented quails reared under TN conditions. However, feed intake, egg production, egg weight, eggshell thickness, eggshell weight and Haugh units were positively influenced by soy isoflavone supplementation in HS groups for quail during the late laying period. Bone mineral density, serum OC, vitamin D, Ca, P levels and ALP activity were significantly improved by soy isoflavone supplementation in both the TN and HS groups in quail during the late laying period. 5. Soy isoflavone supplementation of basal diet significantly improved egg quality and bone mineralisation in quail during the late laying period.
TL;DR: The feasibility of training male ostriches to ejaculate into an artificial cloaca using a teaser female or a dummy is investigated and both methods are reliable, yield ejaculates of high quality and give reproducible results.
Abstract: 1. We investigated the feasibility of training male ostriches to ejaculate into an artificial cloaca (AC) using a teaser female or a dummy. 2. Male ostriches develop desirable behaviour patterns that allow them to be trained to the teaser and the dummy female. Training success can be high as both methods rely on natural stimulation and voluntary ejaculation into the AC provided suitable individuals are identified. 3. The key factors to successful training appear to be: the teaser method - temperament of male ostriches, the crouching behaviour of the female ostriches for the semen collector and acceptance of the collector by the male; dummy method - courtship of humans, learning ability of ostriches to habituate and then to mount a dummy. 4. Both methods are reliable, yield ejaculates of high quality and give reproducible results. The ejaculate volume was 1.09 +/- 0.13 ml, the concentration of spermatozoa 4.21 +/- 0.27 x 10(9)/ml, the total number of spermatozoa 4.67 +/- 0.62 x 10(9) and motility 4.3 +/- 0.1. 5. Commercial ostrich production that relies on natural mating can take advantage of those methods to develop artificial insemination technologies.
TL;DR: A significant increase in breast meat of ducks fed on the Crypthecodinium cohnii enriched diet was observed, and chemical composition, colour, pH, oxidative stability and sensory characteristics of breast muscle were not influenced by the diet.
Abstract: 1. A trial was conducted in order to increase the docosahexaenoic acid (DHA) content in the meat of Muscovy ducks (Cairina moschata domestica L.) fed on a diet supplemented with the microalga Crypthecodinium cohnii. 2. Two diets were provided to 48 male and 48 female ducks, belonging to an Italian rural strain during the last 3 weeks of life: a maize-soybean based diet as the control diet and the same diet supplemented with 5 g/kg microalga meal. 3. Dietary treatment did not induce differences in growth performances and slaughter traits. Similarly, chemical composition, colour, pH, oxidative stability and sensory characteristics of breast muscle were not influenced by the diet. 4. A significant increase of DHA content in breast meat of ducks fed on the Crypthecodinium cohnii enriched diet was observed.
TL;DR: It is shown that microbial phytase enhanced AA digestibility in maize–soy-based diet only at very low AP concentrations, and that CA had no affect on the AID of CP and dispensable and indispensable AA.
Abstract: 1. Two experiments with growing chickens were carried out to study the effects of the inclusion of a microbial phytase (Natuphos® 5000) and citric acid (CA) in maize–soybean-based diets on the performance and apparent ileal digestibility (AID) of crude protein (CP) and amino acids (AA). In both experiments the diets were formulated to contain the same amounts of energy and protein. 2. In the first experiment, data were analysed as a 2 × 2 factorial arrangement with two concentrations of available phosphorus (AP) from one day to 3 weeks of age (3·5 and 2·2 g/kg) and for 3 to 6 weeks (2·7 and 1·4 g/kg), and two inclusions of commercial phytase (0 and 500 FTU/kg) in each period. The AID of CP and dispensable and indispensable AA were not modified by the AP content of the diet. Addition of phytase improved the AID of CP and dispensable and indispensable AA only at low AP levels. 3. In the second experiment, data were analysed as a 3 × 2 factorial arrangement with three concentrations of citric acid (0, 20 and...
TL;DR: On welfare grounds and taking into account other laboratory and field studies, a biphasic method (using consecutive phases of anaesthesia and euthanasia) of controlled atmosphere stunning of broilers is potentially more humane than anoxic or hypercapnic anoxic methods using argon or nitrogen.
Abstract: 1. The effects of controlled atmosphere stunning on the behaviour, physiology and carcase and meat quality of broiler chickens were studied experimentally in a pilot scale plant. 2. Gas mixtures tested were: single phase anoxic mixture (90% Ar in air, <2% O(2)); single phase hypercapnic anoxic mixture (60% Ar, 30% CO(2) in air, <2% O(2)); and biphasic hypercapnic hyperoxygenation mixture (anaesthetic phase, 40% CO(2), 30% O(2), 30% N(2); euthanasia phase, 80% CO(2), 5% O(2), 15% N(2)). 3. Anoxic stunning resulted in the least respiratory disruption, mandibulation and motionlessness, but most head shaking, leg paddling and twitching. Loss of posture occurred soonest with hypercapnic anoxia with the earliest and most twitching and wing flapping in individuals and earliest leg paddling. Biphasic birds were most alert, exhibited most respiratory disruption and mandibulation, and had the latest loss of posture and fewest, but longest bouts of wing flapping and least leg paddling and twitching. 4. Significant and sudden bradycardia and arrhythmia were evident with all gas mixtures and were not related solely to anoxia or hypercapnia. Birds stunned by Ar anoxia showed a slightly more gradual decline from baseline rates, compared with hypercapnic mixtures. 5. Few differences were found between gas mixes in terms of carcase and meat quality. Initial bleeding rate was slowest in biphasic-stunned birds, but total blood loss was not affected. Acceleration of post-mortem metabolism in anoxic-stunned birds was not sufficient to allow de-boning within 5 h without the risk of tough meat. 6. On welfare grounds and taking into account other laboratory and field studies, a biphasic method (using consecutive phases of anaesthesia and euthanasia) of controlled atmosphere stunning of broilers is potentially more humane than anoxic or hypercapnic anoxic methods using argon or nitrogen.
TL;DR: This study supports the conclusions of both laboratory and pilot scale experiments that controlled atmosphere stunning of broiler chickens based upon a biphasic hypercapnic hyperoxygenation approach has advantages, in terms of welfare and carcase and meat quality, over a single phasehypercapnic anoxic approach employing 60% Ar and 30% CO2 in air with <2% O2.
Abstract: 1. The effects of controlled atmosphere stunning on behavioural and physiological responses, and carcase and meat quality of broiler chickens were studied experimentally in a full scale processing plant. 2. The gas mixtures tested were a single phase hypercapnic anoxic mixture of 60% Ar and 30% CO(2) in air with <2% O(2), and a biphasic hypercapnic hyperoxygenation mixture, comprising an anaesthetic phase, 40% CO(2), 30% O(2), 30% N(2), followed by an euthanasia phase, 80% CO(2), 5% O(2), 15% N(2). 3. Birds stunned with Ar + CO(2) were more often observed to flap their wings earlier, jump, paddle their legs, twitch and lie dorsally (rather than ventrally) than those stunned with CO(2) + O(2). These behaviours indicate a more agitated response with more severe convulsions during hypercapnic anoxia, thereby introducing greater potential for injury. 4. Heart rate during the first 100 s of gas stunning was similar for both gases, after which it remained constant at approximately 230 beats/min for CO(2) + O(2) birds whereas it declined gently for Ar + CO(2) birds. 5. In terms of carcase and meat quality, there appeared to be clear advantages to the processor in using CO(2) + O(2) rather than Ar + CO(2) to stun broiler chickens, for example, a much smaller number of fractured wings (1.6 vs. 6.8%) with fewer haemorrhages of the fillet. 6. This study supports the conclusions of both laboratory and pilot scale experiments that controlled atmosphere stunning of broiler chickens based upon a biphasic hypercapnic hyperoxygenation approach has advantages, in terms of welfare and carcase and meat quality, over a single phase hypercapnic anoxic approach employing 60% Ar and 30% CO(2) in air with <2% O(2).
Journal Article•
TL;DR: In this article, the authors investigated the application of RR models for the genetic analysis of egg production in turkeys and found that the RR models overfitted the data, suggesting that the choice of appropriate polynomial order requires careful consideration.
Abstract: Random regression models (RR) have become a popular methodology for the genetic study of longitudinal data since the last decade. The first objective of the current study was to investigate the application of RR models for the genetic analysis of egg production in turkeys. Data collected from a heavy dam line were used to estimate genetic parameters with 2 RR models, one having second-order Legendre polynomials as regression over time (RR2) and another with third-order polynomials (RR3). The second objective was to benchmark the performance of RR models with more conventional methods, so genetic parameters were reestimated using a multitrait (MT) and a repeatability model. To assess the model efficiency of predicting missing values, a reduced data set was used, and for each model, the predicted values of the deleted records were compared with the true values. The RR models were further compared against each other by eliminating the last period and estimating the MS error of the predictions for both models. The repeatability model had the poorest performance in predicting missing values. Heritability estimates from RR2 and MT models were close, whereas the RR3 model estimates were different. Both RR models demonstrated better prediction ability than the MT model. However, when RR models were compared solely, the RR2 model resulted in the smallest MS error. The results indicated that the RR3 model overfitted the data, suggesting that the choice of the appropriate polynomial order requires careful consideration. The present study illustrated that the application of RR models for the genetic analysis of egg production in turkeys is not only feasible but also offers a high accuracy of prediction.
TL;DR: Under the dim, artificial lights inside a poultry house, Oakham Blue hens with black and grey feathers may be less visible to conspecifics than white birds because their plumage reflects at a lower intensity, and it is possible that this novel/unusual appearance may make black or grey OakhamBlue hens more susceptible to feather pecking.
Abstract: 1. This study investigated whether feather damage due to feather pecking and bird behaviour were influenced by plumage colour in Oakham Blue laying hens (black, white, grey colour variants). The reflectance properties of feathers and spectral composition of light environments experienced by the hens were also examined. 2. Nine hundred and seventy-nine birds were inspected and scored for feather damage; 10.5 h of video recordings were examined to record feather pecking and bird behaviour. Feathers and light environments were measured using a USB-2000 spectrometer and DH-2000-CAL-DTH lamp. 3. Oakham Blue birds with white plumage had less feather damage due to feather pecking than black or grey birds. There was more severe feather pecking in the mornings than in the afternoon. White birds feather pecked severely more than black or grey birds, although there were no other behavioural differences between plumage colours. 4. White feathers reflected at a higher intensity than black or grey feathers. However, black and grey feather spectra were relatively flat and the contribution of UV wavelengths to plumage reflection was proportionally greater than that for white feathers. 5. Light intensity inside a poultry house was 100 x (UW/cm2/nm) less than on the range and there was low or no UV reflectance. Under the dim, artificial lights inside a poultry house, Oakham Blue hens with black and grey feathers may be less visible to conspecifics than white birds because their plumage reflects at a lower intensity. Furthermore, the lack of available UV light inside vs. outside and the higher contribution of UV reflectance to black and grey plumage may make black and grey birds appear more different inside the house than white birds. It is possible that this novel/unusual appearance may make black or grey Oakham Blue hens more susceptible to feather pecking.
TL;DR: In a pen study, NH3 flux estimates were performed when clean wheat straw or wood shavings were used as bedding materials in combination with two NH3 control amendments: sodium bisulphate and a commercial premix of phosphoric + hydrochloric+citric acids.
Abstract: 1. In a pen study, NH(3) flux estimates were performed when clean wheat straw or wood shavings were used as bedding materials in combination with two NH(3) control amendments: sodium bisulphate and a commercial premix of phosphoric + hydrochloric + citric acids. 2. Ammonia emissions from wood shavings were 19% greater than from wheat straw around waterers, but statistically similar around feeders. These results could be due to the greater caking observed when wheat straw was used. 3. Sodium bisulphate reduced NH(3) emissions significantly only in the first half of the rearing period; the loss of efficacy in the second half resulted in total NH(3) volatilisation not statistically different from the untreated control. The treatment containing phosphoric + hydrochloric + citric acids did not have a significant effect in decreasing NH(3) emissions. 4. Bird mortality was not affected by the treatments, but broiler weight gain when wheat straw was used was significantly lower than with wood shavings, which could have been caused by the greater caking observed with wheat straw.
TL;DR: It was concluded that current recommendations for biotin in wheat–soy rations for growing turkeys are adequate for normal growth and development and that higher supplements ofBiotin in these experimental conditions did not prevent the occurrence of FPD.
Abstract: 1. A randomised block experiment was conducted to determine the effects of increasing dietary biotin supplementation (0, 200, 800 and 1600 µg/kg) on macroscopic and histological changes associated with the development of foot pad dermatitis (FPD) in growing turkeys. 2. Each treatment was replicated in 4 pens containing 36 birds at the start of the experiment. The birds were weighed and external foot pads were scored at 2-week intervals from 2 to 14 weeks of age. A blood sample was obtained at the same ages from two birds in each pen and tissue from one foot pad was processed for histological examination. Liver samples were obtained for determination of fat content. 3. Increasing dietary biotin supplementation was associated with higher initial plasma concentrations of biotin but there was no effect on external scores or histopathology of foot pad lesions. FPD increased rapidly from 2 to 6 weeks and remained similar thereafter. There was no effect of dietary biotin on liver fat content. 4. The correlations...