Exogenous Phytase Plus Cellulase and Phosphorus Excretion in Lactating Dairy Cows

The Professional Animal Scientist 01/2005; 21:212-216.

ABSTRACT The objectives were to assess the ef-fects of exogenous phytase plus cellulase on P excretion in lactating cows. The ef-fects of an exogenous phytase plus cellu-lase mixture and dietary P content on P partitioning and excretion were evaluated in nine early lactation cows (mean = 27 d in milk); six of the cows were rumi-nally cannulated. Cows were assigned to treatments in replicated (three) 3 × 3 Latin squares, and each cow received each treatment sequentially in three, 21-d periods. Diets were 45% forage (all corn silage) and included supplemental P (high P; 0.47%), no supplemental P (low P; 0.32%), or no supplemental P with ex-ogenous phytase (low P-enzyme; 0.32%). Total collection of milk, urine, and feces was conducted on d 19 to 21 of each pe-riod. There were no effects of dietary P or exogenous phytase plus cellulase on DMI, milk yield, or milk composition. Ex-cretion of feces was unaffected by diet, but urine excretion was less by cows fed the low P diets than by cows fed the high P diets (16.5 vs 21.3 kg/d). Com-pared with cows fed high P diets, cows fed the low P diets had reduced P intake (68.1 vs 103.9 g/d), reduced fecal (34.4 vs 51.3 g/d) and urinary P excretion (2.8 1 To whom correspondence should be ad-dressed: vs 9.2 g/d), and lesser P balance (−8.0 vs. 4.4 g/d). The addition of exogenous phytase plus cellulase did not affect P in-take, milk P, fecal P, or urinary P excre-tion, but apparent P digestibility tended to be greater in cows fed diets supple-mented with the enzyme formulations (50.1% vs 40.5% for low P-enzyme and low P, respectively).

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    ABSTRACT: Accurate estimates of phosphorus (P) availability from feed are needed to allow P requirements to be met with reduced P intake, thus reducing P excretion by livestock. Exogenous phytase supplementation in poultry and swine diets improves bioavailability of P, and limited research suggests that this strategy may have some application in dairy cattle rations. The effects of exogenous phytase and forage particle length on site and extent of P digestion were evaluated with 5 ruminally and ileally cannulated lactating cows (188 ± 35 d in milk). Cows were assigned in a 2 × 2 factorial arrangement of treatments in 2 incomplete Latin squares with four 21-d periods. Diets contained P slightly in excess of National Research Council requirements with all P from feed sources. During the last 4 d of each period, total mixed ration, refusals, omasal, ileal, and fecal samples were collected and analyzed for total P, inorganic P (Pi), and phytate (Pp). Total P intake was not influenced by dietary treatments but Pp intake decreased and Pi intake increased with supplemental phytase, suggesting rapid action of the enzyme in the total mixed ration after mixing. Omasal flow of Pi decreased with phytase supplementation, but we observed no effect of diet in ileal flow or small intestinal digestibility of any P fraction. Fecal excretion of total P was slightly higher and Pp excretion was lower for cows receiving diets supplemented with phytase. Milk yield and composition were unaffected by diets. When phytase was added to the mixed ration, dietary Pp was rapidly degraded before intake and total-tract Pp digestion was increased. The lack of effect of phytase supplementation on dietary P utilization was probably because these late-lactation cows had a low P requirement and were fed P-adequate diets.
    Journal of Dairy Science 11/2013; · 2.55 Impact Factor
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    ABSTRACT: The objective of this study was to evaluate the effect of an exogenous phytase on in vitro residual phosphorus (P) concentration and performance of 30 weaned ¾ Dorper vs ¼ Pelibuey lambs (12.12±1.46 kg BW). In vitro treatments were: 0 and 0.12 mg phytase per g of sorghum, corn gluten meal (CGM), alfalfa hay and experimental diet (70% ground sorghum grain, 16.9% CGM, 12% alfalfa hay, 1.1% calcium carbonate). There were significant (P<0.05) differences in the residual P concentration (%) between 0 and 0.12 mg phytase at 24h of incubation, the values being 0.086 and 0.050 for ground sorghum grain, 0.259 and 0.119 for CGM, 0.365 and 0.240 for alfalfa hay, and 0.276 and 0.240 for the mixed diet with the corresponding 48h values of 0.054 and 0.048 for ground sorghum grain, 0.178 and 0.161 for CGM, 0.198 and 0.131 for alfalfa hay, and 0.237 and 0.211 for the mixed diet. For the performance trial, 30 lambs were allotted to three different groups using complete randomised design, and were fed the experimental diet supplemented with 0, 6 or 12 g t-1 phytase. Parameters recorded were ADG, DM intake, feed conversion (FC), apparent DM digestibility and faecal P excretion (FPE). Phytase supplementation did not change (P>0.05) ADG (251, 294 and 266 g/d), DMI (905, 1119 and 975 g/d), FC (4.06, 4.37 and 3.94). However, phytase addition increased DMD (72.34, 82.54 and 82.57%) and FPE (1.01, 1.09 and 1.26 g/d). It may be concluded that apparent DM digestibility as well as faecal excretion of phosphorus were affected when an exogenous phytase was added to a 70% sorghum grain diet, fed to weaned Dorper x Pelibuey lambs.
    ANIMAL NUTRITION AND FEED TECHNOLOGY 01/2014; 14:183-188. · 0.36 Impact Factor
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    ABSTRACT: A multifunctional transgenic Lactobacillus with probiotic characteristics and an ability to degrade β-glucan and phytic acid (phytate) was engineered to improve nutrient utilization, increase production performance and decrease digestive diseases in broiler chickens. The Bacillus subtilis WL001 endoglucanase gene (celW) and Aspergillus fumigatus WL002 phytase gene (phyW) mature peptide (phyWM) were cloned into an expression vector with the lactate dehydrogenase promoter of Lactobacillus casei and the secretion signal peptide of the Lactococcus lactis usp45 gene. This construct was then transformed into Lactobacillus reuteri XC1 that had been isolated from the gastrointestinal tract of broilers. Heterologous enzyme production and feed effectiveness of this genetically modified L. reuteri strain were investigated and evaluated. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed that the molecular mass of phyWM and celW was approximately 48.2 and 55 kDa, respectively, consistent with their predicted molecular weights. Endoglucanase and phytase activities in the extracellular fraction of the transformed L. reuteri culture were 0.68 and 0.42 U/mL, respectively. Transformed L. reuteri improved the feed conversion ratio of broilers from 21 to 42 days of age and over the whole feeding period. However, there was no effect on body weight gain and feed intake of chicks. Transformed L. reuteri supplementation improved levels of ash, calcium and phosphorus in tibiae at day 21 and of phosphorus at day 42. In addition, populations of Escherichia coli, Veillonella spp. and Bacteroides vulgatus were decreased, while populations of Bifidobacterium genus and Lactobacillus spp. were increased in the cecum at day 21.
    International Journal of Molecular Sciences 07/2014; 15(7):12842-12860. · 2.34 Impact Factor


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