Effectiveness of microbial phytases in improving of growth performance and dietary phytate-phosphorus utilization by pigs

E Delia Veizaj

Department of Animal Production, Faculty of Agriculture and Environment, Agricultural University of Tirana, Albania
etlevade@yahoo.com

Abstract

The microbial phytase preparation (Aspergillus niger, NATUPHOS) was supplemented to a basal ration 750 FTU/kg feed and the effects on growth performance of 60 days old piglets were studied.

The supplementation of microbial phytase improved slightly daily weight gain, feed conversion ratio and increases the digestibility and bioavailability of phosphorus from phytate, reduces the amount of inorganic phosphorus needed to maximize growth and bone mineralization and markedly reduces fecal excretion of phosphorus. Overall a positive effect of the microbial phytase on performance parameters was observed. The P-excretion in the faeces was reduced by 25-30%.

Keywords: Faeces, microbial phytase, P-reduction, piglets, soil pollution

Introduction

Pigs and poultry diets are primarily on cereals, legumes and oilseed products. About two-thirds of phosphorus (P) in these feedstuffs occur as phytates (mio-inositol hekxakisphosphate, InsP6), the salts of phytic acid (Jongbloed et al 1993). Phytate P in plants is a mixed calcium-magnesium-potassium salt of phytic acid that is present as chelate and solubility is very low (Pallauf and Rimbach 1997). Phosphorus in this form is poorly digestible/available for simple-stomached animals (Van Der Klis and Versteegh 1996).

For the utilization of phytate phosphorus, minerals and trace elements bound in phytic acid complexes, hydrolysis of the ester-type bonded phosphate groups of phytic acid by phytase is necessary (Rimbach et al 1994). Phytases (mio-inositol hekxakisphosphate- phosphohydrolase) belong to a special group of phosphatases which are capable of hydrolyzing phytate to a series of lower phosphate esters of myo-inositol and phosphate. Two types of phosphates are known: 3-phytase (EC 3.1.3.8) and 6-phytase (EC 3.1.3.26), indicating the initial attack of the susceptible phosphate ester bond. Monogastric animals intrinsic phytase which is necessary for hydrolysis of phytate present in the plant feedstuffs (Williams and Taylor 1985). However many fungi, bacteria and yeast can produce this enzyme.

With the industrial production of phytase, application of this enzyme to pig’s diet to increase P availability and improve animal performance, as well as reducing environmental pollution has gained widespread attention. The beneficial effects of supplementary phytases on P digestibility and animal performance have been well documented (Rao et al 1999; Ravindran et al 1999).

The efficacy of any enzyme preparation depends not only on the type, inclusion rate and level of activity present, but also on the ability of the enzyme to maintain its activity in the different conditions encountered through the gastrointestinal tract and the conditions used for the pre-treatment of a feedstuff or diet. To evaluate an enzyme preparation, it’s important to characterize the enzymes in terms of pH stability, behavior during technological processing of feeds resistance to proteolytic attack and stability of the enzyme within the digestive tract of the host animal (Igbasan et al 2000). The aim of this study was to test the effects of the microbial phytase (NATUPHOS) on the performance parameters and faecal excretion phosphorus of piglets.

Material and methods 

Twenty piglets (Large White x Landras) of three litters were transferred one month after weaning (60 days old) to flat-decks and allocated to 2 groups (A and B) with 10 animals (5 male and 5 female), respectively. Two piglets from different litters (1 male and 1 female), with the same body weight were housed in every box (experimental unit). The litter origin was taken into account, avoiding that piglets from the same litter were allocated in the same treatment. There were five replications per control group and five also per treated group. The control group (A) was feed with a balanced diet, containing mono calcium phosphate. The experimental group (B) was feed with low level of P, without inorganic phosphorus. All the phosphorus in this group originates from soybean meal. This group was supplemented with NATUPHOS phytase 750 FTU/kg feed.

Ambient room temperature was maintained at 27⁰C for three first weeks and lowered by 1⁰C for each week thereafter. The photoperiod was controlled to provide 12 hour of light and 12 hour of dark in the stall. The ventilation also was provided to ensure good air quality. The basal diet mainly contained maize and soyabean meal and the nutrient contents met or exceeded nutrient requirements recommended by NRC (1998). The diets were offered ad-libitum and animals had free access to water.

During four weeks experimental period body weight (BW), daily weight gain (DWG) and feed conversion ratio (FCR, kg feed/kg body weight gain were measured weekly. Data are presented as arithmetic means with standard error of the mean (Mean ± SEM). One-way analysis of variance and Student’s t-test (P<0.05) were performed to test the differences between two groups.

Results and discussion 

Feeding phytase NATUPHOS was slightly improved the production parameters respectively: final body weight (FBW) by 5.6% and body weight gain (BWG) by 7.3%.

Feed conversion ratio (FCR) was reduced 0.5% to compare with control group, but the differences were not significant. This is in agreement with results obtained by (Cromwell et al 1991). Bone strength was reduced by feeding the low P-diets, 6.5%, compare with control. The P-excretion was reduced by 25-30%, provided that pig’s diets can be supplemented with an economical and efficacious level of phytase that will allow all of the supplemental inorganic P to be removed from the diet (Cromwell and Coffey 1991).

In some region in Albania like Durres region and on the suburb of the capital Tirana, pigs and poultry manure production per unit of arable land greatly exceeds the requirements for reasonable crop production.

Sometimes the farmers have distributed the animal manure in everywhere, because there is no law, which does not allows this kind of distribution. In such situation, it’s difficult to have control on the quantity of the phosphorus and nitrogen in the arable soil and ground water. Actually, in Albania the problem of soil and water pollution are very important yet. The preventive measures at institutional and organizational level are necessary in order to limit the consequence on the future. Referred the average quantity and composition of organic fertilizer, (Table 3 and 4) the P-excretion is nearly 400.000 ton/year. In such situation the utilization of microbial phytase in nutritive ration of pigs is an original way for reduction of soil and water pollution.

Conclusions

• The supplementation of microbial phytase preparation (Aspergillus niger, NATUPHOS) 750 FTU/kg feed induced slightly the growth parameters. However the differences were not significant.

  
  

• Our study resulted at the use of microbial phytase as replacement of inorganic phosphorus in piglet’s diet. The inorganic phosphates in faeces, harmful for the environment, were reduced by 25-30%. This new technology offer substantial benefits to swine production by reducing the potential for environmental problems associated with excess P excretion. Supported by these conclusions, some of the best known companies of swine production in our country have actually included this technology in the everyday practice of the pig’s diet.

Acknowledgement 

Author of this paper would like to thank Ministry of Education and Science (MES) in Albania, for financial support.

References 

Cromwell G L and Coffey R D 1991 Phosphorus -a key essential nutrient, yet a possible major pollutant –its central role in animal nutrition. In: Biotechnology in the Feed Industry. (edited by T.P. Lyons). Nicholasville, USA; Alltech Technical Publications. Pg 133-145.

Cromwell G L, Stahly T S and Randolph J H 1991 Effects of phytase on the utilization of phosphorus in corn-soyabean meal diets by growing-finishing pigs. Journal of Animal Science 69 (Supplement 1): 358-368  http://jas.fass.org/cgi/reprint/69/1/358

Igbasan F A, Männer K, Miksch G, Borris R, Farouk A and Simon O 2000 Comparative studies on the in vitro properties of phytases from various microbial origins. Archive of Animal Nutrition pp 353-373.

Jongbloed A W, Kemme P A and Mroz, Z 1993 The role of microbial phytases in pig production. In: Wenk C and Boessinger M (Editors) Enzymes in Animal Nutrition. Proceedings of the 1^st Symposium Kartause Ittingen, Switzerland, pp 173-180.

NRC 1998 Nutrient Requirements of Swine. 10 th Edition. National Academic Press.

Pallauf J and Rimbach G 1997 Nutritional significance of phytic acid and phytase. Archive of Animal Nutrition 50: 301-319.

Piu Th and Locher E 2001 The annual statistical manual of Livestock in Albania. National Institute of Research Zootechnique. 2: 28-31

Rao R S V, Ravindran V and Reddy V R 1999 Enhancement of phytate phosphorus availability in the diets of commercial broiler and layers. Animal Feed Science and Technology 79: 211-222.

Ravindran V, Cabahug S, Ravindra G and Bryden W L 1999 Influence of microbial phytase on apparent ileal amino acid digestibility of feedstuffs for broilers. Poultry Science 78: 699-706 http://ps.fass.org/cgi/reprint/78/5/699

Rimbach G, Ingelmann H J and Pallauf J 1994 The role of phytase in dietary bioavailability of minerals and trace elements. Ernährungsforschung 39:1-10.

Van Der Klis J D and Versteegh H A J 1996 Phosphorus nutrition of poultry. In: Haresign W and Cole D J A (Editors), Recent Advances in Animal Nutrition pp 71-83.

Williams P J and Taylor T G 1985 A comparative study of phytate hydrolysis in the gastrointestinal tract of the golden hamster (Mesocricetus auratus) and laboratory rat. British Journal of Nutrition 45:429-435.

Received 19 November 2009; Accepted 3 December 2009; Published 7 February 2010

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