• Animal Bioscience
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• 제34권3_spc호
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• pp.354-362
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• 2021

Broiler chickens grow rapidly, and their nutrient requirements change daily. However, broilers are fed three to five diet phases, meaning nutrients are under or oversupplied throughout production. Increasing diet phases improves production efficiency as there is less time in the production cycle that nutrients are in under or over-supply. Nevertheless, the process of administering four or more diets is costly and often impractical. New technologies are now available to blend feed to match the daily nutrient requirements of broilers. Thus, the aim of this review is to evaluate previous studies measuring the impact of increasing feed phases on nutrient utilisation and growth performance, and review recent studies taking this concept to the extreme; precision nutrition - feeding a new diet for each day of the production cycle. This review will also discuss how modern precision feeding technologies have been utilised and the potential that new technologies may bring to the poultry industry. The development of a precision nutrition regime which targets daily requirements by blending dietary components on farm is anticipated to improve the efficiency of production, reduce production cost and therefore improve sustainability of the industry. There is also potential for precision feeding technology along with precision nutrition strategies to deliver a plethora of other management and economic benefits. These include increased fluidity to cope with sudden environmental or market changes, and the ability to alter diets on a farm by farm level in a large, integrated operation. Thus, the future possibilities and practical implications for such technologies to generate a paradigm shift in feed formulation within the poultry industry to meet the rising demand for animal protein is also discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.394-402
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• 2003

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.

• Asian-Australasian Journal of Animal Sciences
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• 제14권3호
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• pp.316-320
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• 2001

Sixteen growing crossbred Anglo-Nubian goats, 10-12 months old, pre-experimental average body weights of $18.3{\pm}0.28kg$ were randomly allotted to four diets to investigate the efficiency of utilisation of diets containing increasing levels of desiccated coconut waste meal (DCWM) in the tropical environment of Samoa, South Pacific region. The four diets were designated as 1, 2, 3 and 4. Diet 1 that has no DCWM served as the control, while diets 2, 3 and contained different levels of DCWM. Voluntary concentrate intake, growth rate, feed efficiency and nutrient digestibility coefficients were measured. Gross energy (GE) and organic matter (OM) values of the diets increased linearly with increase in the levels of DCWM in the diets. Voluntary concentrate intake decreased with increasing proportion of DCWM in the diets. Forage intake increased with increase in the levels of DCWM diets offered to the growing goats. Total voluntary feed intakes were statistical significant (p<0.05) and the goats on diet 4 had the least intake followed by those on diet 3. Goats an diets 1 and 2 were different in total feed intake but not at a significant level (p>0.05). Feed efficiency (FE) followed the trend of voluntary concentrate intake and daily live weight gains. Dry matter digestibility (DMD) was significantly different (p<0.05) among the goats offered the different diets. DMD improved with increasing levels of DCWM. The goats accepted all, the diets that were compounded with the different levels of dried DCWM and this seems to suggest that DCWM have no deleterious effects. However, the best level at which dried DCWM could replace brewers dried grains in the diets of growing goats is at 38.5% (diet II). Based on voluntary feed intake, live-weight gain and apparent nutrient digestibility coefficients of the goats it could be concluded that DCWM based diets merits further attention as a locally available feed source in ruminants nutrition in the Pacific Island countries where feed availability is seasonal.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.254-261
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• 2005

The over-expression of Bcl-2 has greatly improved the culture period, specific growth rate, and maximum viable cell density of NS0 cells culture under low serum condition. Further analysis of these data suggests that a saturation model of the Monod type can be used to represent the relationships of specific growth rate and initial serum concentration. The ${\mu}_{max}$ and $K_s$ for the Bcl-2 cell line is $0.927day^{-1}\;and\;0.947\%(v/v)$ respectively, which are $21\%$ greate and $7\%$ lower respectively than its control counterpart. Study on the amino acid supplementation revealed that Bcl-2 cell lines possess greater improvement in the specific growth rate and maximum viable cell density compared to the control cell lines. A further increase in the amino acid supplementation has resulted a $17\%$ decrease in specific growth rate and no improvement in maximum viable cell density in the control culture. However, the Bcl-2 cell line exhibited a better growth characteristic in this culture condition compared to that of control cell lines. The higher specific growth rate and maximum viable cell density of the Bcl-2 cell line in medium fortified with serum and MEM EM suggested a more efficient nutrient metabolism compared to that in the control cell line. The low serum and amino acid utilisation rate and the higher cell yield may prove to be important in the development of serum/protein free culture.

• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1410-1415
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• 2017

Objective: This experiment investigated the effect of isonitrogenous replacement of groundnut cake (GNC) by rice gluten meal (RGM) and maize gluten meal (MGM) at 75% level on nutrient intake, apparent digestibility, growth performance and related blood constituents in growing Sahiwal cattle. Methods: Eighteen Sahiwal calves were divided into three groups, based on average body weight (87.24 kg) and age (6 to 12 mo), and treatments were assigned to the different groups randomly. The first group (GP-I) was kept as control and received GNC-based concentrate mixture. In second (GP-II) and third (GP-III) groups, 750 g/kg nitrogen (N) of GNC was substituted by RGM and MGM respectively, with similar forage:concentrate ratio (56:44). Results: The 90 days of experimental feeding revealed that intake of dry matter, crude protein and digestibility coefficients for all nutrients did not differ among groups. Furthermore, although N balance was greater ($p{\leq}0.05$) for GP-III than GP-I and GP-II, average daily gain was similar between GP-I and GP-II but greater ($p{\leq}0.05$) for GP-III. In addition, feed efficiency and related haematological variables did not differ due to treatments. Conclusion: Nutritional worth of GNC and RGM was highly comparable in terms of intake, digestibility and growth in growing calves. However, MGM was found to be more efficacious in improving growth rate than RGM at 75% replacement level of GNC protein.

• Asian-Australasian Journal of Animal Sciences
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• 제20권6호
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• pp.900-907
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• 2007

Three male Gayal (Bos frontalis) and three male Yunnan Yellow cattle (Bos taurus) were fed pelleted lucerne and measurements made of digestibility, nitrogen utilisation, rumen fermentation and microbial population and key plasma metabolites. Total actual dry matter intake was similar but when expressed in terms of live weight or metabolic live weight feed intakes were significantly higher (p<0.05) for Gayal than cattle. Apparent digestibilities of dry matter, organic matter, fibre and dietary nitrogen were similar for both Gayal and cattle. Rumen ammonia nitrogen and total volatile fatty acids were significantly higher (p<0.05) for Gayal than cattle and total numbers of viable rumen bacteria, cellulolytic and amylolytic bacteria, but not proteolytic bacteria nor protozoa, were significantly greater (p<0.05) for Gayal than cattle. Although Gayal have a different rumen ecology to cattle, similar digestive parameters were exhibited. Further research is required to establish relationship between rumen ecology and digestive parameters.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1228-1232
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• 2001

Forty five Soviet Chinchilla rabbits weaned at 35 d of age were fed 5 experimental diets prepared by using oat plant meal ($T_2,\;T_4$) and tall fescue hay ($T_3,\;T_5$) at 25% and 50% level along with control ($T_1$). The gain in body weight at 84 d of age decreased with test material substitution, however, the differences were non significant when compared with oat plant meal and were significant (p<0.05) with tall fescue hay at both the levels. Feed conversion ratio also deteriorated with test material and its increasing proportion and the differences were significant (p<0.05). The performance-index calculated were 42.1, 36.7, 29.4, 33.3 and 18.8 in $T_1,\;T_2,\;T_3,\;T_4$ and $T_5$, respectively. Digestibility of all the organic nutrients decreased significantly (p<0.05) with test material incorporation, as a result nutritive value of the test diets decreased linearly. Nitrogen balance as per cent of intake was higher in oat plant meal substituted diet compared to tall fescue substituted diet. Cost per kg live weight gain was lowest with 50% oat plant meal followed by 25% oat plant meal incorporation. It was highest with tall fescue hay substitution. Nutritive value of oat plant meal as calculated was DCP 5.1%, TDN 35.8% and that of tall fescue hay was DCP 6.5%, TDN 30.8%. Thus, oat plant meal can be substituted safely up to 25% in the feeding regime of weaner rabbits whereas, for tall fescue hay the safe limit is below 25% level and needs to be ascertained.

• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.53-60
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• 2020

Objective: The current study was carried out to examine the response of different levels of fat and protein in calf starter on nutrient utilisation, nitrogen metabolism, weight gain, blood parameters, and immunity level in pre-ruminant calves. Methods: Twenty four calves (5 days old) were divided into six groups in a 2×3 factorial design, with two levels of fat (10% and 14%) and three levels of protein (18%, 21%, and 24%). The calves were kept in individual pens for 120 days and fed with whole milk (1/10th of body weight) and calf starter ad-libitum. Daily dry matter intake was recorded; whereas body weight was taken on fortnightly basis to calculate average daily gain. During the growth trial blood samples were collected at 30 days interval to estimate blood glucose, albumin, total protein, total leucocyte count, total immunoglobulins and immunoglobulin G levels. A metabolic trial of seven days was carried out to find out the digestibility of different nutrients. Results: The dry matter intake was reduced (p<0.05) with higher fat and protein levels whereas feed conversion efficiency was improved (p<0.05) with higher protein level. Different levels of fat and protein in calf ration did not affect average daily gain in calves. The dry matter, organic matter, and crude protein digestibility were significantly (p<0.01) higher with increased level of protein. The nitrogen retention was also significantly higher (p<0.05) at 24% protein level, similarly the total immunoglobulin was significantly (p<0.05) high in higher protein fed groups, showed better immunity. Conclusion: The present finding suggested that 10% fat and 18% protein level of calf starter could be used in Sahiwal calves for optimum performance in terms of weight gain and immunity.

• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1542-1548
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• 2001

Wheat straw was treated on laboratory scale with 4% urea at a moisture level of 50% along with different amount of HC1 to fix various levels of ammonia (30, 40, 50 and 60%) and stored for 4 weeks. Result, revealed a significant (p<0.01) increase in CP content of the samples where HC1 was added. The CP content of the straw was only 7.8%, which increased to 14.1, 16.0, 15.0 and 15.2% with the addition of acid. Similarly the concentrations of NDF, ADF and hemicellulose was significantly different due to HC1 addition. The level of HC1 recommended was to trap 30% ammonia as there was not significant difference in CP content of straw due to addition of 4 levels of acids. Results of in vivo experiment conducted on nine buffaloes divided randomly into three groups of three animals in each revealed no significant difference in the intake of DM, OM, NDF, ADF, cellulose and hemicellulose in group I (ammoniated straw), group II (HC1 treated ammoniated straw) and group III (HC1 treated ammoniated straw + 1 kg barley grain), but the intake of CP was significantly (p<0.01) more in group III as compared to other 2 groups. The digestibility of DM, OM and CP was significantly (p<0.01) more in groups where HCI treated straw was fed as compared to only ammoniated straw fed group, whereas there was no significant difference in the digestibility of NDF, ADF and cellulose in 3 groups. Intake was significantly higher of nitrogen (p<0.05), calcium (p<0.01) and phosphorus (p<0.01) in group III as compared to other two groups. Animals in all the 3 groups showed positive nitrogen, calcium and phosphorus balance, though the balances of all the 3 nutrients were significantly higher in group III as compared to other 2 groups. Rumen fermentation study conducted in 3 rumen fistulated buffaloes in $3{\times}3$ latin square design offering the same 3 diets as in group I to III revealed that rumen pH was alike statistically in 3 groups and at various time intervals. The mean ammonia-N concentration was significantly (p<0.01) more in group II and III as compared to group I. The mean TVFA concentration (mM/100 ml SRL) were 6.46, 7.84 and 8.47 in 3 groups respectively and different statistically (p<0.01). Results revealed no significant difference in the activities of carboxy methyl cellulase, urease or protease at both the time of sampling (0 h and 4 h) in all the 3 groups of animals.