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Marlborough, United Kingdom

Kuhn I.,AB Vista | Partanen K.,Mtt Agrifood Research Finland
Journal of Animal Science | Year: 2012

The effect of a thermotolerant 6-phytase produced by Trichoderma reesei on performance and apparent total tract digestibility (ATTD) of P and Ca was evaluated in 192 weaned piglets (randomized block design; 16 replicates; 2 piglets each). Diets based on wheat (Triticum aestivum), barley (Hordeum vulgare), oat (Avena sativa), soybean (Glycine max) meal, and whey protein with adequate [positive control (PC)] or reduced [negative control (NC)] Ca and P levels were fed for 46 d after weaning. The PC and NC diets contained 8.0 and 6.4 g/kg Ca and 2.9 and 1.9 g/kg digestible P, respectively. Pelleted diets contained 0, 500, or 1000 phytase units (FTU)/kg. Growth performance and G:F were measured during starter (25 d) and weaner pig (21 d) periods. The ATTD of Ca and P was determined by spot sampling at the end of the weaner pig period (8 pens per treatment over 5 consecutive d). Data were analyzed using a mixed model with random block effect and fixed effect of dietary P and phytase level and their interaction. Dietary P level did not affect ADG or G:F of piglets over the entire feeding period (P > 0.10) whereas phytase increased G:F (P < 0.05). During the starter period, phytase linearly enhanced (P < 0.05) ADG (258, 266, and 292 g) and G:F (639, 677, and 664 g gain/kg feed DM) without further increase in the weaner pig period (P > 0.10). A P × phytase interaction (P < 0.05) was observed for ATTD of P, more so for NC (48, 61, and 68%, respectively) than PC diets (52, 62, and 61%). The ATTD of Ca was higher (P < 0.05) for PC than NC diets (68 vs. 58%) and increased quadratically by phytase (61, 65, and 63%). In conclusion, the phytase tested enhanced piglet performance during the postweaning period and increased ATTD of P and Ca. © 2012 American Society of Animal Science. All rights reserved.

Akter M.,University of New England of Australia | Graham H.,AB Vista | Iji P.A.,University of New England of Australia
Journal of Food, Agriculture and Environment | Year: 2015

An in vitro experiment was conducted to evaluate the effect of different dietary minerals on phytate hydrolysis by microbial phytase enzyme and to measure the residual phytate content after phytate digestion. Calcium (0, 6, 8, 10 g kg-1 of diet), Fe (0, 70, 80, 90 mg kg-1 of diet), Zn (0, 30, 40, 50 mg kg-1 of diet) or Na (0, 1.5, 2.5 and 3.5 g kg-1 of diet) were incubated with a Na-phytate solution, with phytase enzyme (500 FTU kg-1 of diet) at pH 2.5 or 6.5. The phytate concentration was set at 0.27% to mimic the phytate level in a typical corn-soybean meal-based poultry diet. Inclusion of Ca, Zn and Fe significantly (p < 0.05) reduced the phytate phosphorus hydrolysis at both pH values but the effect was strongest at pH 6.5. Irrespective of the pH, adding Na also inhibited (p < 0.05) phytate phosphorus hydrolysis; however, the negative effect was more pronounced at pH 2.5 than 6.5. Residual phytate content (mg) after phytate digestion was higher (p < 0.05) at pH 6.5 than at 2.5 in the presence of Ca, Zn and Fe. The reverse was the case in the presence of Na. These in vitro results demonstrated that increased concentrations of dietary Ca, Fe, Zn and Na could reduce phytate phosphorus hydrolysis, but such a response would need to be tested in animal feeding trials. © 2015, World Food Ltd. and WFL Publishers. All rights reserved.

Walk C.L.,AB Vista
Animal Production Science | Year: 2016

High dietary calcium (Ca) can negatively influence growth performance and reduce phosphorus, protein and amino acid digestibility in broilers and pigs. In addition, high dietary Ca will precipitate with phytate at pH conditions within the small intestine. Previous research reported that high dietary Ca significantly reduced phytase efficacy through precipitation with or competition for binding sites on the phytate molecule. However, microbial phytases are active at pH ranges where phytate is soluble and hydrolyse phytate rapidly to reduce the likelihood of phytate precipitating with Ca, suggesting the effect of dietary Ca on the efficacy of these phytases may be reduced. Even with such phytases there may still be problems observed due to particularly high concentrations of dietary Ca, which can occur as a result of a reduction in Ca not being applied in the presence of a phytase and/or if Ca concentrations in the diet exceed expectations. For example, when total Ca was analysed in 795 broiler and pig diets, on average, there was 0.22% more Ca present than expected. This means that if a diet was formulated to contain 0.80% total Ca, the analysed value could be as high as 1.02%, almost 25% above the expected dietary Ca concentration. The discrepancy between the expected and analysed total Ca may have implications on chemical and physical properties within the gastrointestinal tract, dietary phytate solubility, nutrient digestibility and phytase efficacy. The present paper aims to highlight factors influencing the effect of Ca on phytase efficacy, encompassing the differences among published book values for total Ca content of ingredients, the difference between Ca sources and their affinity for phytate, and finally how these factors influence the Ca to P ratio and thus phytase efficacy. © CSIRO 2016.

Cabezon F.A.,Purdue University | Stewart K.R.,Purdue University | Schinckel A.P.,Purdue University | Barnes W.,The Hanor Company | And 3 more authors.
Animal Reproduction Science | Year: 2016

This study evaluated the effect of supplemental dietary betaine at three concentrations (0.0%, 0.63% and 1.26%) on semen characteristics, quality and quality after storage on boars. The trial was conducted between 22 July and 1 October 2014 in a boar stud located in Oklahoma. Boars were blocked by age within genetic line and randomly allotted to receive 0% (CON, n (line T) = 22, n (line L) = 10), 0.63% (BET-0.63%, n (line T) = 21, n (line L) = 6) or 1.26% (BET-1.26%, n (line T) = 23, n (line L) = 7). The diets containing betaine were fed over 10 weeks, to ensure supplemental betaine product (96% betaine) daily intakes of 16.34 and 32.68. g, for the BET-0.63% and BET-1.26% diets, respectively. Serum homocysteine concentrations were less for animals with betaine treatments (P = 0.016). Rectal temperatures of the boars were unaffected by betaine diets. Betaine tended to increase total sperm in the ejaculates when collectively compared with data of the control animals (P = 0.093). Sperm morphology analysis indicated there was a greater percent of sperm with distal midpiece reflex (P = 0.009) and tail (P = 0.035) abnormalities in boars fed the BET-1.26% than boars fed the BET-0.63% diet. Betaine concentration in the seminal plasma was greater in boars with betaine treatments, with animals being fed the 0.63% and 1.26% diets having 59.2% and 54.5% greater betaine concentrations in seminal plasma as compared with boars of the control group (P = 0.046). In conclusion, betaine supplementation at 0.63% and 1.26% tended to increase sperm concentration in the ejaculates by 6% and 13%, respectively, with no negative impacts on semen quality when 0.63% of betaine was included in the diet. © 2016 Elsevier B.V.

Ghosh T.K.,West Bengal University of Animal and Fishery Sciences | Haldar S.,West Bengal University of Animal and Fishery Sciences | Bedford M.R.,AB Vista | Muthusami N.,West Bengal University of Animal and Fishery Sciences | Samanta I.,West Bengal University of Animal and Fishery Sciences
Journal of Animal Physiology and Animal Nutrition | Year: 2012

The study compared the effects of an antibiotic growth promoter (AGP), yeast (Saccharomyces cerevisiae) and yeast cell wall (YCW) on performance, microbiology and histo-morphology of the small intestine and humoral immune responses in Ross 308 broilers. The treatments (eight replicates/treatment, n=12/replicate) were negative control (NC, without AGP), positive control (PC, supplemented with bacitracin methylene disalicylate, 400mg/kg), Y and YCW (supplemented with yeast and YCW, respectively, 1000mg/kg). Live weight at 42days improved (p=0.086) in the PC, Y and YCW groups. Feed conversion ratio was better (p=0.039) in the YCW group compared with the other groups. Antibiotic growth promoter in the PC group shortened the villi in duodenum (p=0.044). Mucosal Escherichia coli number was higher in the PC group (p<0.001), whereas in the digesta E. coli number was lower (p=0.001) in the PC, Y and YCW groups in relation to the NC. Mucosal Salmonella populations increased (p=0.0001) in the PC group, whereas in the digesta, all treatments reduced the Salmonella (p=0.0001). Following oral challenge with Salmonella pullorum, YCW increased E. coli numbers on the mucosa (p<0.001) whereas in the digesta the Y group had lower (p<0.0001) number of E. coli. In the digesta, Salmonella count was lower in the YCW group compared with the other treatments (p<0.01). Yeast cell wall -treated birds exhibited better (p<0.05) humoral immune response against Newcastle disease which was far more persistent over time than in any other treatments. It was concluded that the yeast and the yeast cell wall may have effects identical to BMD on performance of broilers and thus may constitute an effective replacement strategy in the dietary regimens for broiler chickens. © 2011 Blackwell Verlag GmbH.

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