• Korean Journal of Poultry Science
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• v.25 no.2
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• pp.65-70
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• 1998

A 16-wk feeding trial was conducted to investigate the proper feeding regimen on the performance of Korean Native Chicken(KNC) consuming broiler diets. Commercial KNC are normally fed 3 kinds of diets during their life span, i. e., starter(S, 0 to 3wk of age), grower(G, 4 to 7wk of age), and finisher(F, 8 to l6wk of age) diets. In this trial, four feeding regimen were employed:T1(S-G-F), T2(S-G-G), T3(S-S-F), and T4(S-F-F). Day-old 360 KNC were randomly allotted to 12 pens: three pens per treatment, and 30 birds per pen. At the end of the trial, the BW of T2 was significantly better than that of T3(P<0.05), and T1 and T4 were intermediate. No significant difference were found in feed intake, feed conversion ratio, and viability among treatments. It appears that, in terms of BW gain, the T2 is the recommendable feeding regimen for KNC consuming broiler diets.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.904-911
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• 2019

Objective: The study was conducted to evaluate the effects of night light regimen on growth performance, antioxidant status and health of Lingnan Yellow broiler chickens from 1 to 21 days of age. Methods: A completely randomized factorial design involved 2 photoperiods (constant lighting [CL], 24 L:0 D and intermittent lighting [INL], 17 L:3 D:1 L:3 D)${\times}2$ light intensities (10 lx and 30 lx). A total of one thousand six hundred and eighty 1-d-old Lingnan Yellow broiler chicks were randomly divided into 4 treatments with 6 replicates (70 birds per replicate). The experiment lasted for 21 d. Results: Photoperiods and light intensities had no effect on average daily gain, feed conversion ratio, and mortality of the broiler chickens (p>0.05). The INL had a significant effect on average daily feed intake (p<0.05) of broiler chickens compared with CL. Photoperiod and light intensity had an interactive effect on melatonin (MT) concentration (p<0.05). At CL, reducing light intensity increased MT concentration; INL birds had higher MT but MT concentration was not affected by light intensity. There was an interactive effect on glutathione peroxidase (GPx) and catalase (CAT) in serum and total antioxidant capability (T-AOC) in liver between photoperiod and light intensity. With the decrease of light intensity, the activities of GPx and CAT in serum and T-AOC in liver increased in CL group (p<0.05). Broiler chickens reared under INL had better antioxidant status and 10 lx treatments had higher activities of CAT in serum than 30 lx (p<0.05). Different photoperiods and light intensities had no effect on malondialdehyde. There was an interaction between photoperiod and light intensity on serum creatine kinase (CK) concentration (p<0.05). At CL, the elevated light intensity resulted in an increase in CK content; INL birds had lower CK concentration especially in low light intensity group. Besides, INL and low light intensity significantly reduced the concentration of serum corticosterone and heat shock protein 70 (p<0.05). Serum immunoglobulin M contents were increased in broiler chickens reared under the INL compared with CL group (p<0.05). Conclusion: Results above suggest that the night light regimen of INL and 10 lx could be beneficial to the broiler chickens from 1 to 21 days of age due to the better health status and electricity savings.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1581-1586
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• 2009

The present study was conducted to determine the effects of two types of housing systems and early age feed restriction on stress and fear reactions, and performance in broiler chickens raised in a hot, humid tropical climate. On day 1, chicks were housed either in windowless environmentally controlled chambers (temperature was set at 32$^{\circ}C$ on day 1 and gradually reduced to 23$^{\circ}C$ by day 21) or in conventional open-sided houses (OH) with cyclic temperatures (minimum, 24$^{\circ}C$; maximum, 34$^{\circ}C$). An equal number of chicks from each housing system was subjected to either ad libitum feeding (AL) or 60% feed restriction on day 4, 5 and 6 (FR). The CH birds showed greater weight gain, higher feed consumption and better feed conversion ratios (FCR) than their OH counterparts. Feeding regimen had negligible effect on overall performance. Neither housing nor feeding regimen had a significant (p<0.05) effect on mortality rate. Although the CH birds were less stressed, as measured by plasma corticosterone concentration (CORT), than those of OH, the former showed longer TI duration suggesting higher magnitude of underlying fearfulness. A significant (p<0.05) effect of housing on heterophil/lymphocyte ratios was only noted among the AL birds where the CH birds had higher values than OH. Collectively, these results suggest that although OH birds had poorer performance and higher level of stress than CH, the former were less fearful. Although FR had negligible effect on growth performance, the regimen alleviated both stress and fear reactions in broilers.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.432-444
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• 2001

In this manuscript, several effective feeding and management systems to reduce environmental pollution in swine production have been briefly introduced. It is logical that reducing the excretion of nutrients in manure should be the first step to reduce the environmental impact of pig production. it is evident that the excretion of nitrogen and phosphorus can be reduced when more digestible or available feedstuffs are used. Also, it is well known that proper feed processing can reduce anti nutritional factors (ANF) and improve nutrient digestibilities. Supplementation of effective feed additives can reduce excretion of nitrogen and phosphorus due to efficient feed utilization. These include enzymes (e.g., phytase), antibiotics, probiotics, organic acids and growth hormones ($\beta$-agonists and porcine somatotropin). One of the most effective ways to reduce pollutants from swine manure is to use synthetic amino acids in feed manufacturing. Many studies showed that reduction of 2 to 4% unit (U) of dietary protein with supplemental amino acid (AA) could dramatically reduce (15 to 20%) nitrogen excretion. Regarding feeding strategies, it has been recognized that phase feeding regimen could be used to reduce nitrogen and phosphorous excretion by feeding pigs in better agreement with age and physiological state. Feeding barrows and gilts separately, known as split sex feeding, can also decrease excretion of nitrogen and phosphorus. With the increasing concerns on the negative impact of animal production systems on the environment, animal nutritionists and producers should be aware that sustainability of animal agriculture is as important as high production performance. Therefore, some feeding and management strategies described in this manuscript will help to reduce environmental pollution in swine production. Proper combination of feeding regimen and environment-friendly diet formulation through nutritional approach will be more effective to reduce nutrient excretion in swine production system compared to single approach to do so.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.12
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• pp.1758-1762
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• 2001

Equal number of red jungle fowl (JF) and commercial broiler chickens (CB), raised in battery cages, were provided a single complete diet (control) or a choice of a complete diet, ground corn and ground soybean from 21 to 56 days of age. There were significant genotype ${\times}$ feeding regimen interactions for several traits measured suggesting CB and JF responded differently to the two feeding regimens. The single fed CB had better growth and feed conversion ratios (FCR) than those under choice feeding. However, the body weight and FCR of JF were not affected by feeding regimen. While the single fed and choice-fed JF consumed similar amount of protein during days 21 to 55, the protein intake of the choice-fed CB was lower than the control. From days 21 to 55, irrespective of genotype, choice-fed chicks consumed less energy than their single fed counterparts. Regardless of genotype, the trend in the proportion of each feed consumed was similar with complete diet>corn>soybean. In conclusion, while choice-fed JF were capable to select nutrient necessary for maximum growth, choice feeding was detrimental to growth and feed conversion ratio in CB.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1137-1146
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• 2000

This study was carried out to establish an optimum number of phase feeding regimen which enable to reduce nutrients excretion without affecting growth performance and to investigate the effects of different feeding regimens on growth performance, nutrients excretion and carcass characteristics in finishing pigs. A total of 120 finishing pigs (an average initial body weight of 54.3 kg) were assigned to the feeding trial and 12 pigs were assigned to the metabolic trial. Treatments included one phase (54 to 104 kg), two phase (54 to 80 and 80 to 104 kg), three phase (54 to 70, 70 to 90 and 90 to 104 kg) and four phase (54 to 65, 65 to 80, 80 to 95, 95 to 104 kg) feeding regimens. Experimental diets were formulated to contain 16% crude protein for one phase feeding regimen, 16% and 12% crude protein for two phase feeding regimen, 16%, 14% and 12% crude protein for three phase feeding regimen, and 16%, 14.7%, 13.4% and 12% crude protein for four phase feeding regimen, respectively. Although there were no significant differences in any criteria measured during the entire experimental period, pigs reared in three phase feeding regimen grew slightly faster than those reared in other feeding regimens and showed a tendency to increase ADFI during the whole experimental period. The metabolic trial indicated that there were no significant differences in DM (dry matter), CP (crude protein) and P (phosphorus) digestibilities. However, fecal nutrient excretion except P was significantly influenced by feeding regimens. DM excretion of one phase feeding group was significantly higher than that of three phase feeding group and daily fecal N (nitrogen) excretion of one phase feeding group was higher than that of other phase feeding groups (p<0.05). Three and four phase feeding regimens resulted in 12% lower fecal N and DM excretion than one phase feeding regimen. Blood urea concentrations were lower for pigs reared in two, three and four phase feeding regimens than for those reared in one phase feeding regimen (p<0.05). Three phase feeding regimen for the finishing period showed better carcass grade than one phase feeding regimen, though the difference was not significant. The tenth rib fat thickness of pigs fed on four phase feeding regimen was reduced most and there was a trend that backfat thickness decreased as the number of phases increased. Feed cost per kg weight gain was significantly low in four phase feeding group than one phase feeding group (p<0.05). In summary, it seemed that producers generally oversupply the expensive nutrients for the finishing pigs. High nutrient diets do not always guarantee high growth rate of pigs and cause more unwanted nutrient excretion. It rather seems that meeting nutrient requirements for the each growth phase is more important for the reduction of pollutants and economical pork production.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.4
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• pp.573-586
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• 2011

Along with the recent changes in animal feed supply circumstances, many enzyme and probiotic feed supplements have been introduced and applied to pigs and chicken diets. Therefore, both selection of the appropriate feed supplements and their proper supplementation becomes critical to justify the supplementation. Meta-analysis was proposed as an appropriate tool to assess the large amount of relevant information. In this review, reliable data from recent publications was compounded then analyzed to determine the best practice of effective enzyme supplementation from the perspectives of animal species, age, characteristics of feed, target substrates, optimum multi enzymes combination and intended objectives. The results of the analysis suggested pratical methods of probiotic supplementation regarding intestinal microbiota, physiological limitation of probiotics, maximization of the probiotic benefit and synergism with prebiotic supplements.

• Journal of Animal Environmental Science
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• v.16 no.1
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• pp.61-80
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• 2010

Poultry welfare has recently appeared as worldwide concern as well as Korea. The recent action plan for farm animal welfare introduced by the European Commission intends to expand the body of regulatory standards. In this context, many countries and/or organization are on the verge of establishing the most optimum poultry welfare standards. To establish the most optimum standards, comparative analysis of feeding regimen before and after welfare-bestowed environment need to be preceded. Most guidelines or standards for poultry welfare do not suggest the nutritional requirements and feeding system in detail, although it is deterimental especially for the farmer. This review intends to find scientific base to establish detailed welfare feeding guidelines. However, only limited research has been conducted in the view of actual poultry welfare. The results indicated the incidence of SDS, ascites, skeletal dysfunctions caused by fast growth rate in broiler, feather pecking and cannibalism in laying hen, and feed restriction in broiler breeder could be reduced by changing nutritional regimen and feeding strategies or both. The regimen and feeding strategies are certainly near to the direction that the poultry welfare ought to be in the right track. In this article, feeding and drinking guidelines in many standards as well as welfare feeding experiments have been reviewed and compared In the view of chicken productivity, welfare physiology and poultry health.

• Animal Bioscience
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• v.35 no.5
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• pp.690-697
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• 2022

Objective: This study aimed to evaluate the effect of the ad libitum and restricted feeding regimen on fasting heat production (FHP) and body composition. Methods: Twelve Hubbard broilers breeders were selected with the same body weight and submitted in two feeding regimes: Restricted (T1) with feed intake of 150 g/bird/d and ad libitum (T2). The birds were randomly distributed on the treatments in two runs with three replications per treatment (per run). The birds were adapted to the feed regimens for ten days. After that, they were allocated in the open-circuit chambers and kept for three days for adaptation. On the last day, oxygen consumption (VO₂) and carbon dioxide production (VCO₂) were measured by 30 h under fasting. The respiratory quotient (RQ) was calculated as the VCO₂/VO₂ ratio, and the heat production (HP) was obtained using the Brower equation (1985). The FHP was estimated throughout the plateau of HP 12 hours after the feed deprivation. The body composition was analyzed by dual-energy X-ray absorptiometry scanning at the end of each period. Data were analyzed for one-way analysis of variance using the Minitab software. Results: The daily feed intake was 30 g higher to T2 (p<0.01) than the T1. Also, the birds of the T2 had significatively (p<0.05) more oxygen consumption (+3.1 L/kg^0.75/d) and CO₂ production (+2.2 L/kg^0.75/d). That resulted in a higher FHP 359±14 kJ/kg^0.75/d for T2 than T1 296±17.23 kJ/kg^0.75/d. In contrast, the RQ was not different between treatments, with an average of 0.77 for the fasting condition. In addition, protein and fat composition were not affected by the treatment, while a tendency (p<0.1) was shown to higher bone mineral content on the T1. Conclusion: The birds under ad libitum feeding had a higher maintenance energy requirement but their body composition was not affected compared to restricted feeding.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.3
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• pp.390-395
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• 2016

This study was conducted to investigate the effect of nocturnal light pulses (NLPs) on the feed intake and metabolic rate in geese. Fourteen adult Chinese geese were penned individually, and randomly assigned to either the C (control) or NLP group. The C group was exposed to a 12L:12D photoperiod (12 h light and 12 h darkness per day), whereas the NLP group was exposed to a 12L:12D photoperiod inserted by 15-min lighting at 2-h intervals in the scotophase. The weight of the feed was automatically recorded at 1-min intervals for 1 wk. The fasting carbon dioxide production rate ($CO_2$ PR) was recorded at 1-min intervals for 1 d. The results revealed that neither the daily feed intake nor the feed intakes during both the daytime and nighttime were affected by photoperiodic regimen, and the feed intake during the daytime did not differ from that during the nighttime. The photoperiodic treatment did not affect the time distribution of feed intake. However, NLPs lowered (p<0.05) the mean and minimal $CO_2$ PR during both the daytime and nighttime. Both the mean and minimal $CO_2$ PR during the daytime were significantly higher (p<0.05) than those during the nighttime. We concluded that NLPs lowered metabolic rate of the geese, but did not affect the feed intake; both the mean and minimal $CO_2$ PR were higher during the daytime than during the nighttime.