FEED RESOURCE AVAILABILITY AND UTILIZATION IN SMALLHOLDER PIG FARMS IN SRI LANKA

Ravindran, V.,Cyril, H.W.,Nadesalingam, P.,Gunawardene, D.D. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.4

Data on available feed resources, feeding practices and nutrient adequacy of rations under small farm conditions in Sri Lanka were obtained in a baseline survey involving 104 pig farms. The results showed that a wide range of non-conventional feedstuffs are used for pig feeding under typical small farm conditions and that dietary protein quality is a major factor limiting productivity. Following the survey, two on-farm trials were conducted to evaluate cheaper, alternative feeding strategies. In trial 1, a test diet was formulated using several non-conventional feedstuffs and compared with a commercial feed that is normally fed in the farms. In trial 2, the possibility of improving growth rates by amino acid supplementation was evaluated. The results demonstrated that feed costs can be considerably lowered through these packages. Some problems inherent to on-farm livestock trials are highlighted.

UTILIZATION OF NON-CONVENTIONAL FEED RESOURCES IN POULTRY PRODUCTION: RESULTS OF ON-FARM TRIALS

Ravindran, V.,Cyril, H.W. Asian Australasian Association of Animal Productio 1995 Animal Bioscience Vol.8 No.4

Though a variety of non-conventional feedstuffs have been successfully evaluated in research stations in Asian countries, there had been little adoption of these technologies at the small farm level. The methodology and results of three separate on-farm trials evaluation the possible use of some non-conventional feedstuffs in broiler diets under small farm conditions in Sri Lanka are reported in this paper. In all trials, the commercial mash, that in normally used in the farms, served as the control. In trials 1 and 2, 5 and 10% cassava leaf meal, respectively, was substituted (w/w) for the commercial mash and fed to broilers for six weeks. In trial 3, several non-conventional feedstuffs (cassava leaf meal, rubber seed meal, ipil ipil leaf meal and died poultry manure) were substituted (w/w) for the commercial mash at levels of 15-20%. The results demonstrated that these non-conventional feed resources can be used in broiler diets under small farm conditions, with no adverse effects on performance. The salient features of on-farm animal research are highlighted.

Mineral Retention in Young Broiler Chicks Fed Diets Based on Wheat, Sorghum or Maize

Thomas, D.V.,Ravindran, V. Asian Australasian Association of Animal Productio 2010 Animal Bioscience Vol.23 No.1

The aim of the present study was to determine the changes in mineral retention of broiler chicks fed diets based on wheat, sorghum or maize during the first two weeks post-hatch. The retention of five major minerals (calcium, phosphorus, potassium, sodium and magnesium) and four trace minerals (iron, manganese, zinc and copper) was determined on days 3, 5, 7, 9 and 14 of age. The retention coefficients of individual minerals differed widely and the retention coefficients of major minerals were found to be considerably higher than those of trace minerals. Age effects were significant (p<0.05) for all minerals. In general, mineral retention coefficients were highest at day 3, declined to day 7, and remained unchanged to day 14. Decline in mineral retention with age was similar on all three diets. The cereal effect was significant (p<0.05) for several minerals, with a general tendency for the sorghum-based diet to have greater retention than maize- or wheat-based diets.

Effects of Phytase Supplementation of Diets with Two Tiers of Nutrient Specifications on Growth Performance and Protein Efficiency Ratios of Broiler Chickens

Selle, P.H.,Ravindran, V.,Pittolo, P.H.,Bryden, W.L. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.8

In two feeding experiments male and mixed-sex broiler chicks were offered diets based on sorghum and a wheatsorghum blend with two tiers of nutrient specifications, without and with microbial phytase (600 and 800 FTU/kg), from 7-25 and 1-42 days post-hatch, respectively. The nutrient specifications for protein, amino acids, energy density and phosphorus (P) of standard diets were reduced to formulate the modified diets on a least-cost basis. Calculated differences in nutrient specifications between standard and modified diets ranged from 14.3 to 17.1 g/kg crude protein, 0.24 to 0.40 MJ/kg apparent metabolisable energy (AME) and 1.06 to 1.20 g/kg available P. In both experiments, reduced nutrient specifications had a negative impact on growth rates and feed efficiency and phytase supplementation had a positive influence on growth performance and protein efficiency ratios (PER). Phytase addition to the less expensive, modified diets either partially or entirely compensated for reduced growth performance and, consequently, feed costs per kg of live weight gain were reduced. In Experiment 1, phytase increased (p<0.001) nitrogen-corrected AME (AMEn) from 15.39 to 15.89 MJ/kg dry matter. For nitrogen (N) retention there was an interaction (p<0.05) between diet type and phytase as the effects of phytase on N retention were more pronounced in the modified diets, with an increase from 0.512 to 0.561. These results demonstrate the positive effects of phytase on protein and energy utilisation, in addition to its established liberation of phytate-bound P and illustrate the feasibility of assigning nutrient replacement values to the feed enzyme for consideration in least-cost ration formulations. Further work is, however, required to define the most appropriate reductions in nutrient specifications in association with phytase supplementation.

Influence of Phytase and Xylanase Supplementation on Growth Performance and Nutrient Utilisation of Broilers Offered Wheat-based Diets

Selle, P.H.,Ravindran, V.,Ravindran, G.,Pittolo, P.H.,Bryden, W.L. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.3

Individual and combined supplementation of phosphorus-adequate, wheat-based broiler diets with exogenous phytase and xylanase was evaluated in three experiments. The effects of the enzyme combination in lysine-eficient diets containing wheat and sorghum were more pronounced than those of the individual feed enzymes. The inclusion of phytase plus xylanase improved (p<0.05) weight gains (7.3%) and feed efficiency (7.0%) of broilers (7-28 days post-hatch) and apparent metabolisable energy (AME) by 0.76 MJ/kg DM. Phytase plus xylanase increased (p<0.05) the overall, apparent ileal digestibility of amino acids by 4.5% (0.781 to 0.816); this was greater than the responses to either phytase (3.6%; 0.781 to 0.809) or xylanase (0.7%; 0.781 to 0.784). Absolute increases in amino acid digestibility with the combination exceeded the sum of the individual increases generated by phytase and xylanase for alanine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, phenylalanine, threonine, tyrosine and valine. These synergistic responses may have resulted from phytase and xylanase having complementary modes of action for enhancing amino acid digestibilities and/or facilitating substrate access. The two remaining experiments were almost identical except wheat used in Experiment 2 had a higher phytate concentration and a lower estimated AME content than wheat used in Experiment 3. Individually, phytase and xylanase were generally more effective in Experiment 2, which probably reflects the higher dietary substrate levels present. Phytase plus xylanase increased (p<0.05) gains (15.4%) and feed efficiency (7.0%) of broiler chicks from 4-24 days post-hatch in Experiment 2; whereas, in Experiment 3, the combination increased (p<0.05) growth to a lesser extent (5.6%) and had no effect on feed efficiency. This difference in performance responses appeared to be 'rotein driven'as the combination increased (p<0.05) nitrogen retention in Experiment 2 but not in Experiment 3; whereas phytase plus xylanase significantly increased AME in both experiments. In Experiments 2 and 3 the combined inclusion levels of phytase and xylanase were lower that the individual additions, which demonstrates the benefits of simultaneously including phytase and xylanase in wheat-based poultry diets.

Effects of Dietary Lysine and Microbial Phytase on Growth Performance and Nutrient Utilisation of Broiler Chickens

Selle, P.H.,Ravindran, V.,Ravindran, G.,Bryden, W.L. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.7

The effects of offering broilers phosphorus-adequate diets containing 10.0 and 11.8 g/kg lysine, without and with 500 FTU/kg exogenous phytase, on growth performance and nutrient utilisation were determined. Each of the four experimental diets was offered to 6 replicates of 10 birds from 7 to 28 days of age. Effects of treatment on performance, apparent metabolisable energy, apparent ileal digestibility of amino acids and bone mineralisation were examined. Both additional lysine and phytase supplementation improved (p<0.05) weight gain and feed efficiency, with interactions (p<0.05), as phytase responses were more pronounced in lysine-deficient diets. Phytase improved (p<0.05) apparent metabolisable energy, which was independent of the dietary lysine status. Bone mineralisation, as determined by percentage toe ash, was not affected by treatment, which confirms the phosphorus-adequate status of the diets. Phytase increased (p<0.05) the apparent ileal digestibility of the sixteen amino acids assessed. Unexpectedly, however, the dietary addition of 1.8 g/kg lysine, as lysine monohydrochloride, increased (p<0.05) the ileal digestibility of lysine per se and also that of isoleucine, methionine, phenylalanine, valine, aspartic acid, glutamic acid and tyrosine. In addition, there were significant interactions (p<0.05) between additional lysine and phytase supplementation for arginine, lysine, phenylalanine, aspartic acid, glutamic acid, glycine and serine digestibilities, with the effects of phytase being more pronounced in lysine-deficient diets. The possible mechanisms underlying the increases in amino acid digestibility in response to additional lysine and the interactions between lysine and microbial phytase in this regard are discussed. Also, consideration is given to the way in which phytate and phytase may influence ileal digestibility of amino acids.

The Effect of Stocking Density on the Behaviour of Broiler Chickens

Thomas, David G.,Son, Jang-Ho,Ravindran, Velmurugu,Thomas, Donald V. The Korean Society of Poultry Science 2011 韓國家禽學會誌 Vol.38 No.1

A 35-day trial was conducted to examine the influence of floor density on the behaviour of broiler chickens. Day-old male broilers (n=756) were randomly assigned to one of four stocking densities (6 replicates of n=13, 25, 38 and 50) in 24 identical 2.6 $m^2$ pens. These stocking densities were coded very low (VL), low (L), medium (M) and high (H) and contained a floor space allowance per bird of 2,000 $cm^2$, 1,000 $cm^2$, 667 $cm^2$ and 500 $cm^2$, respectively. Scan sampling of all groups was carried out at 15-min intervals during two 1-h periods (10.00 h~11.00 h and 14.00 h~15.00 h) for five days each week. The numbers of birds engaged in different behavioural activities were recorded. It was found that the most common behaviour in all densities was lying. There was no clear effect of density during wks 1~4 of the trial, but in wk 5 birds in the L, M and H groups showed lower levels (P=0.07) of lying behaviour when compared to birds in the VL group suggesting that an increase in animal density results in decreased opportunities for undisturbed rest. This observation is supported by standing and walking behaviour, which was lower (P<0.05) in the VL group in wk 5. Foraging behaviour measured in the study by the numbers of birds pecking the ground declined as the trial progressed, but scratching increased in 2 wk then decreased. Birds in the VL group showed higher (P<0.05) level of pecking the ground behaviour compared to birds in the L, M and H groups, but scratching behaviour higher (P<0.05) and lower (P<0.05) in VL of 1 wk and 2 wk respectively. However, a peak in aggressive behaviour was observed in wk 2 and birds in the VL group showed less (P<0.05) agonistic behaviour than birds in the H and M groups. Other behaviours (dustbathing, preening, eating or drinking) were not influenced (P>0.05) by stocking density.

The Effect of Stocking Density on the Behaviour of Broiler Chickens

David G. Thomas,Jang Ho Son,Velmurugu Ravindran,Donald V. Thomas 韓國家禽學會 2011 韓國家禽學會誌 Vol.38 No.1

A 35-day trial was conducted to examine the influence of floor density on the behaviour of broiler chickens. Day-old male broilers (n=756) were randomly assigned to one of four stocking densities (6 replicates of n=13, 25, 38 and 50) in 24 identical 2.6 ㎡ pens. These stocking densities were coded very low (VL), low (L), medium (M) and high (H) and contained a floor space allowance per bird of 2,000 ㎠, 1,000 ㎠, 667 ㎠ and 500 ㎠, respectively. Scan sampling of all groups was carried out at 15-min intervals during two 1-h periods (10.00 h~11.00 h and 14.00 h~15.00 h) for five days each week. The numbers of birds engaged in different behavioural activities were recorded. It was found that the most common behaviour in all densities was lying. There was no clear effect of density during wks 1~4 of the trial, but in wk 5 birds in the L, M and H groups showed lower levels (P=0.07) of lying behaviour when compared to birds in the VL group suggesting that an increase in animal density results in decreased opportunities for undisturbed rest. This observation is supported by standing and walking behaviour, which was lower (P<0.05) in the VL group in wk 5. Foraging behaviour measured in the study by the numbers of birds pecking the ground declined as the trial progressed, but scratching increased in 2 wk then decreased. Birds in the VL group showed higher (P<0.05) level of pecking the ground behaviour compared to birds in the L, M and H groups, but scratching behaviour higher (P<0.05) and lower (P<0.05) in VL of 1 wk and 2 wk respectively. However, a peak in aggressive behaviour was observed in wk 2 and birds in the VL group showed less (P<0.05) agonistic behaviour than birds in the H and M groups. Other behaviours (dustbathing, preening, eating or drinking) were not influenced (P>0.05) by stocking density.

Influence of Palm Kernel Meal Inclusion and Exogenous Enzyme Supplementation on Growth Performance, Energy Utilization, and Nutrient Digestibility in Young Broilers

Abdollahi, M.R.,Hosking, B.J.,Ning, D.,Ravindran, V. Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.4

The objective of the present study was to investigate the influence of palm kernel meal (PKM) inclusion and exogenous enzyme supplementation on growth performance, nitrogen-corrected apparent metabolizable energy (AMEn), coefficient of apparent ileal digestibility (CAID) and total tract retention of nutrients in young broilers fed corn-based diets. Four inclusion levels of PKM (no PKM [PKM0], 8% [PKM8], 16% [PKM16], and 24% [PKM24]) and two enzyme additions were evaluated in a $4{\times}2$ factorial arrangement of treatments. A total of 384, one-d-old male broilers (Ross 308) were individually weighed and allocated to 48 cages (eight broilers/cage), and cages were randomly assigned to eight dietary treatments. Results indicated that the inclusion of 8% and 16% PKM increased (p<0.05) the weight gain compared to the PKM0 diet. Birds fed the PKM8 diets had the highest (p<0.05) feed intake. Weight gain and feed intake were severely reduced (p<0.05) by feeding the PKM24 diet. Enzyme supplementation increased weight gain (p<0.05), independent of PKM inclusion level. In PKM0 and PKM8 diets, enzyme addition significantly (p<0.05) lowered feed conversion ratio (FCR); whereas enzyme addition had no effect on FCR of birds fed PKM16 and PKM24 diets. In PKM0 and PKM16 diets, enzyme addition significantly (p<0.05) increased CAID of nitrogen and energy but had no effect in the PKM8 and PKM24 diets. Inclusion of PKM into the basal diet, irrespective of inclusion level, enhanced (p<0.05) starch and fat digestibility. Inclusion of PKM at 16% and 24% resulted in similar CAID of neutral detergent fiber (NDF) but higher (p<0.05) than that of the PKM0 and PKM8 diets. Enzyme addition, regardless of the level of PKM inclusion, significantly (p<0.05) increased CAID of NDF. There was a significant (p<0.05) decrease in AMEn with PKM inclusion of 24%. The present data suggest that inclusion of PKM in broiler diets could be optimized if PKM-containing diets are formulated based on digestible amino acid contents and supplemented with exogenous enzymes. If amino acid digestibility and AME of PKM considered in the formulation, it can be included in broiler diets up to 16% with no deleterious effects on growth performance.