Avian Science Research Center

Ayr, United Kingdom

Avian Science Research Center

Ayr, United Kingdom
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Bravo D.,Pancosma S. A. | Pirgozliev V.,Avian Science Research Center | Pirgozliev V.,National United University | Rose S.P.,National United University
Journal of Animal Science | Year: 2014

A total of 210, 1-d-old Ross 308 male broiler chickens were used in an experiment to investigate the effects of a supplementary mixture containing 5% carvacrol, 3% cinnamaldehyde, and 2% capsicum on dietary energy utilization and growth performance. The 2 diets were offered ad libitum to the chickens from 0 to 21 d of age. These included a maizebased control diet and the control diet with 100 g/t of supplementary plant extracts. Dietary apparent ME, N retention (NR), and fat digestibility (FD) coefficients were determined in the follow-up metabolism study between 21 and 24 d of age. Feeding the mixture of carvacrol, cinnamaldehyde, and capsicum increased weight gain by 14.5% (P = 0.009), improved feed efficiency by 9.8% (P = 0.055), and tended to increase (P = 0.062) carcass energy retention and reduce (P = 0.062) total heat loss compared with feeding the control diet. There was a 16.1% increase (P = 0.015) in carcass protein retention but no difference in carcass fat retention. Feeding plant extracts improved dietary FD by 2.1% (P = 0.013) but did not influence dietary NR. Supplementation of plant extract resulted in a 12.5% increase (P = 0.021) in dietary NE for production (NEp), while no changes in dietary ME were observed. The experiment showed that although dietary essential oils did not affect dietary ME, they caused an improvement in the utilization of energy for growth. Plant extracts may affect metabolic utilization of absorbed nutrients. Studies that have focused solely on the effect of plant extracts on ME alone may well have not detected their full nutritional value. © 2014 American Society of Animal Science. All rights reserved.

Pirgozliev V.,Avian Science Research Center | Pirgozliev V.,Harper Adams University College | Bedford M.R.,AB Vista Feed Ingredients
British Journal of Nutrition | Year: 2013

A total of 364 female Ross 308 chicks (1 d old) were used in the present study conducted in floor pens to investigate the effects of graded levels of supplementary bacterial phytase on dietary energy utilisation and growth performance. For this purpose, four maize-soyabean-based diets were offered to the birds from 0 to 21Â d of age. These included a suboptimal P negative control (NC, 3·0Â g/kg non-phytate P), NC+250 phytase units (FTU)/kg feed, NC+500Â FTU and NC+2500Â FTU. The effect of phytase activity on bird growth performance was best described as a linear relationship between increasing dose and increased feed intake (P<Â 0·001), but was quadratic for body-weight gain (P=Â 0·002) and feed efficiency (P=Â 0·023). There was no significant response (P>0·05) of dietary apparent metabolisable energy (AME) to supplementary phytase. The birds fed phytase increased their retention of total carcass energy in a linear fashion (P=Â 0·009) with increased phytase dose. The efficiency of dietary AME used for overall carcass energy retention also improved (P=Â 0·007) in a linear manner with increased dietary phytase activity. Dietary net energy for production (NEp) increased (P=Â 0·047) with an increase in phytase dose following a linear pattern, as an increase of 100Â FTU increased dietary net energy by 15·4Â J (estimated within the range of doses used in the present experiment). Dietary NEp was more highly correlated with performance criteria than dietary AME, and it seems to be a more sensitive way to evaluate broiler response to phytase supplementation. Copyright © The Authors 2012.

Adebiyi A.O.,Avian Science Research Center | Olukosi O.A.,Avian Science Research Center
British Poultry Science | Year: 2015

Abstract: The apparent (AIAAD) and standardised ileal amino acid digestibility (SIAAD) of wheat distillers dried grains with solubles (wheat-DDGS) was determined for broilers and turkeys at 28 d using two experiments. A total of 84 male Ross 308 broiler chicks (Experiment 1) or 84 male BUT 10 turkey poults (Experiment 2) were offered a nutrient-adequate diet from d 1 to 23. On d 23, birds in each experiment were allocated to 4 treatments consisting of a nitrogen-free diet (NFD) (with or without protease) and an assay diet containing wheat-DDGS as the only source of amino acids (with or without protease) in a randomised complete block design. In Experiments 1 and 2, the coefficient of AIAAD or SIAAD of Lys and Asp were low irrespective of protease. In Experiment 1, the coefficient of AIAAD ranged from 0.35 (Ala) to 0.75 (Pro) without protease, whereas the range was 0.42 (Thr) to 0.82 (Pro) with protease. Protease improved the coefficient of AIAAD for Arg and Pro and tended to improve the coefficient of AIAAD for Met. Without protease, the coefficient of SIAAD ranged from 0.51 (Ala) to 0.84 (Pro), whereas the range was from 0.65 (Ala) to 0.93 (Pro) with protease. Protease improved the coefficient of SIAAD of Arg, Leu, Phe, Met, Val and Pro. In Experiment 2, the coefficient of AIAAD was lower than 0.50 for all amino acids except for Glu (0.70) and Pro (0.81) without protease. On the other hand, the coefficient of SIAAD ranged from 0.41 (Thr) to 0.89 (Pro) without protease, whereas the range was from 0.56 (Arg) to 0.88 (Pro) with protease supplementation. With the exception of Cys and Pro, protease improved the coefficient of AIAAD and SIAAD of all other amino acids by 0.05–0.19. It was concluded that the AIAAD and SIAAD of wheat-DDGS are variable and are generally greater in broilers compared to turkeys at 28 d of age. Protease improved the ileal digestibility of a large number of amino acids in wheat-DDGS for broilers and turkeys. © 2015, © 2015 British Poultry Science Ltd.

Sparks N.H.C.,Avian Science Research Center
Avian Biology Research | Year: 2011

The earliest avian eggshells probably lacked pigmentation but, in part to help protect the eggs from predators, many species of bird have evolved a diverse range of coloured shell markings. However, the wide variation in shell colour and pigment pattern arise out of probably no more than three molecules, protoporphyrin, biliverdin and zinc biliverdin chelate. These molecules are constructed from four pyrrole rings (tetrapyrroles) but, while their synthesis pathways are well defined, the site(s) of shell pigment synthesis is less well defined. It is probable that biliverdin is synthesised in the uterus. While there is evidence that protoporphyrin is also synthesised in the uterus the evidence for this is more circumstantial. What is known is that pigment is secreted from the surface epithelial cells of the uterus into the uterine fluid and hence onto the shell. It is notable that the protoporphyrin content the uterine tissue of white-egg laying birds is not dissimilar to that of brown-egg laying birds, the control mechanisms being exerted at the level of protoporphyrin release from the surface epithelial cells into the lumen of the uterus. Similarly white-shelled eggs are not necessarily devoid of pigment. While pigment is normally concentrated on the outer surface of the shell there are many species of bird that incorporate pigment into the outer half or third of the shell. This has stimulated research into potential functional roles for shell pigments, including substituting for calcium carbonate when calcium is limiting and improving shell strength through 'lubricating' the calcite crystals.

Pirgozliev V.,Avian Science Research Center | Bedford M.R.,Avian Science Research Center | Bedford M.R.,Syngenta | Acamovic T.,Avian Science Research Center
British Poultry Science | Year: 2010

1. The aim was to examine the effect of dietary xylanase on the availability of nutrients for laying hens when fed on wheat-rye-soy-based diets. The basal diet was formulated to contain 11·03 MJ/kg apparent metabolisable energy (AME), and the experimental diets were formulated by supplementing the basal diet with four different activities of xylanase (400, 800, 1200 and 1600 xylanase units (XU)/kg). 2. The AME and nitrogen metabolisability coefficients of xylanase-supplemented diets were 1·2% and 7·1%, respectively, greater than in the control diet. 3. Supplementary xylanase significantly improved the coefficients of metabolisability of indispensable, dispensable and total amino acids by 8·2%, 6·9% and 7·8%, respectively, and led to a significantly linear response of total amino acid metabolisability coefficient to xylanase. There was a range of effects within the indispensable amino acids with xylanase supplementation (1600 XU/kg) significantly improving the metabolisability of threonine by 4·9%, but having no have effect on lysine. The response of total amino acid retention to added xylanase was a significant quadratic function and suggests that 800 XU/kg is the optimum supplementary dosage. 4. Supplementary xylanase significantly improved sulphur metabolisability in a linear fashion to a maximum of 2·3% higher than that of the control diet. In terms of daily retention, most of the minerals responded in a quadratic manner to dietary xylanase, as the suggested optimal supplementary level was between 800 and 1200 XU/kg. 5. The yolk colour of the birds receiving 1200 and 1600 XU/kg was 0·33 and 0·28 units (Roche score); these were 4·1% and 3·5%, respectively, darker than the yolk of the birds given the control diet. 6. Birds receiving xylanase had a significantly higher weight gain than those fed on the unsupplemented diet. Feed intake, the number of eggs per hen per d, dirty and cracked eggs, and feed conversion ratio for egg production were not affected by xylanase. These data suggest that use of a xylanase may improve the metabolisability of many nutrients, but that such effects may not always benefit production parameters. © 2010 British Poultry Science Ltd.

Pirgozliev V.,Avian Science Research Center | Bedford M.R.,Vista Feed Ingredients | Acamovic T.,Vista Feed Ingredients | Mares P.,Vista Feed Ingredients | Allymehr M.,Vista Feed Ingredients
British Poultry Science | Year: 2011

1. Four diets were offered to broiler chickens from 7 to 17d of age; these included a phosphorus-adequate positive control (PC) (4 7g/kg available P), a sub-optimal P negative control (NC, 2 5g/kg available P) with (500 and 12500FTU/kg) and without phytase. Dietary apparent metabolisable energy (AME), dietary net energy for production (NEp), the efficiency of AME retention (Kre), heat production and total tract amino acid digestibility coefficients were determined. The determination of NEp involved a comparative slaughter technique in which growing chickens were fed the experimental diets ad libitum. 2. Feed intake, weight gain and feed conversion efficiency increased significantly in a dose dependent manner in response to dietary phytase activity. Overall, the NEp of the phytase supplemented diets significantly improved by approximately 15 6% compared with the negative control, while dietary AME was unaffected. Although phytase did not affect AME, the large increase in the NEp demonstrated that dietary phytases improves energy utilisation, i.e. diverting more energy, not accounted for in the AME procedure, for production. This is largely a result of the stimulatory effect that phytase has on feed intake rather than on digestibility of the diet. 3. Overall, the diet supplemented with 12500FTU had 6 4% significant improvement in total tract digestibility coefficients of the total amino acids compared with the negative control. With regard to individual amino acids, the impact of phytase was far more pronounced for threonine, an important component of the gastrointestinal mucin, than for other amino acids. 4. Dietary NEp was more highly correlated with performance criteria than dietary AME and seems to be a more sensitive way to evaluate broiler response to phytase supplementation. © 2011 British Poultry Science Ltd.

Cross D.E.,Avian Science Research Center | McDevitt R.M.,Avian Science Research Center | Acamovic T.,Avian Science Research Center
British Poultry Science | Year: 2011

Herbs, thyme essential oil (EO) and condensed tannin (CT) extracts were compared for their effects, as dietary supplements, on broiler growth performance, nutrient digestibility and volatile fatty acid (VFA) profiles in the gut. Cooked meat from the birds fed on diets with 4 herbs and an EO extract was compared by a taste panel against those fed on the control treatment, for organoleptic properties in the meat. 2. Female broiler chicks were fed on wheat-soybean meal diets from 0-42d of age. These chicks were given either the basal diet (control), or the basal diet with one of rosemary, garlic or yarrow herbs, mimosa, cranberry or grapeseed CT's, or thyme EO supplements (8 treatments in total). Body weight (BW) and feed consumption (FC) were measured. 3. The garlic supplement tended to improve growth rate over the first 7d, while mimosa CT and thyme EO supplements reduced weight gains. The mimosa supplement in diets significantly reduced FC to d 21. Meanwhile, the addition of a cranberry supplement reduced the digestibility of DM, OM and N, compared with the controls. Dietary thyme EO, yarrow, rosemary and garlic supplements modified caecal isovaleric and isobutyric acid proportions (presented as 'Other VFA'; p<0.05). Dietary herb significantly affected the intensity of meat flavour, and the potential of observing both garlic and abnormal flavours. There were large differences between the consumption of red and white meat samples, while meat temperature affected several flavour attributes. 4. Broiler performance and digestibility for birds given dietary garlic and grapeseed CT supplements were similar to the controls, and these supplements appear suitable for dietary inclusion. Careful choices are necessary when selecting dietary plant extract supplements for broilers, but beneficial effects can be observed. © 2011 British Poultry Science Ltd.

Dixon L.M.,Animal and Veterinary Science Research Group | Sparks N.H.C.,Avian Science Research Center | Rutherford K.M.D.,Animal and Veterinary Science Research Group
Poultry Science | Year: 2016

Early life experiences can be important in determining offspring phenotypes and may influence interaction with the environment and hence health, welfare, and productivity. The prenatal environment of poultry can be divided into the pre-lay environment and the egg storage/incubation environment, both of which can affect offspring outcomes. The ability to separate maternal and egg/incubation effects makes birds well suited to this type of research. There are many factors, including feeding and nutrition, environmental conditions, husbandry practices, housing system, social environment, infectious environment, and maternal health status, that can influence both the health and performance and behavior and cognition of the offspring. There are some aspects of the environments that can be changed to produce beneficial effects in the offspring, like addition of certain additives to feed or short changes in incubation temperatures, while other aspects should be avoided to reduce negative effects, such as unpredictable feeding and lighting regimens. Measures of offspring characteristics may prove to be a useful method of assessing parent stock welfare if known stressors result in predictable offspring outcomes. This has the advantage of assessing the parent environment without interfering with the animals and possibly affecting their responses and could lead to improved welfare for the animals. © 2016 The Author 2015. Published by Oxford University Press on behalf of Poultry Science Association.

Dixon L.M.,Avian Science Research Center | Dixon L.M.,University of Guelph | Duncan I.J.H.,University of Guelph | Mason G.J.,University of Guelph
Animal Welfare | Year: 2010

Severe feather pecking, a potentially stereotypic behaviour in chickens (Gallus gallus), can be reduced by providing enrichment. However, there is little comparative information available on the effectiveness of different types of enrichment. Providing forages to birds is likely to decrease feather-pecking behaviour the most, as it is generally thought that feather pecking stems from re-directed foraging motivation. Yet, other types of enrichment, such as dustbaths and novel objects, have also been shown to reduce feather pecking. In order to develop a practical and effective enrichment, these different possibilities must be examined. Using a Latin Square Design, 14-week old birds were given each of four treatments: i) forages; ii) novel objects; iii) dustbaths; or iv) no enrichment. The amount of feather-pecking behaviour and the number of pecks to the enrichments were recorded. Results showed feather pecking to be highest when no enrichment was present and lowest when the forages were present, with the other two enrichments intermediate. This was despite the fact that the numbers of pecks birds gave to the forages and dustbaths were not significantly different, suggesting that they were similarly used. Thus, we suggest here that forage enrichments are most effective at alleviating feather pecking at least in the short term and attempts should be made to develop poultry housing that allows for natural foraging behaviour. Following this, providing any kind of enrichment will increase bird welfare and is therefore still beneficial. © 2010 Universities Federation for Animal Welfare.

Olukosi O.A.,Avian Science Research Center | Dono N.D.,Avian Science Research Center | Dono N.D.,Gadjah Mada University
Journal of Animal Science | Year: 2014

Two experiments, each consisting of 2 trials, were conducted to investigate the effect of feeding benzoic acid (BA) and turmeric meal (TM) individually or in combination (Exp. 1) or garlic meal (GM) and TM individually or in combination (Exp. 2) on growth performance, digesta pH, gut morphology, and nutrient utilization in broiler chickens. Diets consisted of a nutrient-adequate control diet and the control diet with added BA (2 g/kg), TM (10 g/kg), BA (1 g/kg) plus TM (5 g/kg), and BA (2 g/kg) plus TM (10 g/kg) in Exp. 1. In Exp. 2, in addition to the same control diet as Exp. 1, the control diet with added GM (10 g/kg), TM (10 g/kg), GM plus TM at 5 g/kg each, and GM plus TM at 10 g/kg each were used. Each treatment had 6 replicate floor pens with 10 chickens per replicate. On d 14, 5 broiler chickens from each floor pen were transferred to metabolism cages and continued on their respective diets. Body weight and feed intake data were collected on d 0 and 21, excreta were collected from chickens in metabolism cages on d 19 and 20, and ileal digesta were collected on d 21. Digesta pH was measured at the crop, proventriculus, jejunum, and cecum. Jejunum sections were collected from chickens in Exp. 1 to study gut morphology. In Exp. 1, only the combination of BA and TM tended (P < 0.10) to improve weight gain but there were no effects on G:F. The combination of BA and TM at both inclusion rates decreased (P < 0.05) digesta pH in the crop, jenunum, and ceca. There were no treatment effects on ileal DM or total tract DM retention, but supplementation of BA or TM alone or in combination increased (P < 0.01) apparent ME (AME) and nitrogen-corrected AME (AMEn) relative to the control diet. In Exp. 2, TM alone or combined with GM improved (P < 0.05) weight gain and G:F compared to the control. Supplementation of TM alone or in combination with GM at the rate of 10 g/kg each reduced (P < 0.05) digesta pH in the crop, proventriculus, and ceca but had no effect at the jejunum. The combination of GM and TM improved (P < 0.01) ileal DE, AME, and AMEn. In conclusion, BA, TM, and GM individually or in combination with wheat–soybean meal based diets adequate in nutrients and energy selectively improved growth performance, modified digesta pH and intestinal growth, and increased the efficiency of dietary energy use. © 2014 American Society of Animal Science. All rights reserved.

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