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: One approach to reduce nutrient losses from livestock farms is to apply biological waste treatment systems such as biological nitrogen (N) removal or enhanced biological phosphorus (P) removal (EBPR) to reduce the nutrient content of land-applied waste. The EBPR process takes advantage of the ability of P-accumulating organisms (PAOs) to sequester excess P as polyphosphate granules in their cytoplasms, yielding a P-depleted liquid effluent and a P-enriched biomass. Biological N removal systems result in the conversion of organic or ammonia-N to innocuous N 2 gas. Understanding the variation in parameters such as chemical oxygen demand (COD), total and volatile suspended solids (TSS and VSS), and ammonia-N (NH 3 -N) is necessary to design these systems. Our objectives were to evaluate the effects of diet and manure separation on parameters important to reactor design. Waste was collected from nine cows fed a high P diet (0.47% P), a low P diet (0.32% P), or low P with exogenous phytase plus cellulase (0.32% P), in a replicated Latin square design (three 3 × 3 squares). Total collection of milk, urine, and feces was conducted on days 19 to 21 of each period, a mixed slurry (urine, feces, and water) was created, and slurry was separated mechanically to generate liquid effluent. Slurry contained more COD, solids, N, and P than liquid effluent, but the COD:P ratio was similar in the two wastes. The ratio of COD:N was higher in slurry than in separator effluent, but the ratio in both wastes was sufficient to support biological N removal. The P content of slurry, liquid effluent, and manure solids from cows fed low P was lower than from cows fed high P, and the COD content of effluent was higher with the low P diet. The COD:P ratio of all wastes was sufficient to support EBPR and biological N removal, but variation was observed with diet. Waste from cows fed low P had a higher COD:P ratio than that of cows fed high P, and waste from cows fed the enzyme-supplemented diet had a lower COD:N ration than that of cows fed the control diet. Dairy manure slurry and effluent will support EBPR and biological N removal. Dietary effects on parameters important to the design of advanced waste treatment systems were observed, but were not of a magnitude that would affect reactor design. Keywords. Lactating cows, Manure treatment, Research-scale manure separation. he development of strategies to reduce the nitrogen (N) and phosphorus (P) content of land-applied livestock manure is an important aspect of long-term efforts to reduce nutrient pollution of water re-sources. Reducing the nutrient content of land-applied waste reduces potential nutrient losses, allows livestock producers to increase the rate of manure application to a fixed land base, and/or reduces the amount of land needed for spreading ma-nure. Approaches to reducing the nutrient content of waste include dietary nutrient management (refining diets to maxi-mize efficiency of utilization of consumed nutrients) and physical or biological nutrient removal systems. Physical separation of manure solids and liquids via gravity or screening reduces organic loading to the liquid treatment system, removes large particles that could plug or damage nozzles in the irrigation system used in land Article was submitted for review in September 2004; approved for publication by the Structures & Environment Division of ASAE in March 2005.
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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 01/2014; 15(7):12842-12860. · 2.46 Impact Factor


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