• Animal Bioscience
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• 제35권5호
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• pp.648-658
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• 2022

Objective: The identification of nonlinear mixed models that describe the growth trajectory of New Zealand rabbits was performed based on weight records and carcass measures obtained using ultrasonography. Methods: Phenotypic records of body weight (BW) and loin eye area (LEA) were collected from 66 animals raised in a didactic-productive module of cuniculture located in the southern Piaui state, Brazil. The following nonlinear models were tested considering fixed parameters: Brody, Gompertz, Logistic, Richards, Meloun 1, modified Michaelis-Menten, Santana, and von Bertalanffy. The coefficient of determination (R²), mean squared error, percentage of convergence of each model (%C), mean absolute deviation of residuals, Akaike information criterion (AIC), and Bayesian information criterion (BIC) were used to determine the best model. The model that best described the growth trajectory for each trait was also used under the context of mixed models, considering two parameters that admit biological interpretation (A and k) with random effects. Results: The von Bertalanffy model was the best fitting model for BW according to the highest value of R² (0.98) and lowest values of AIC (6,675.30) and BIC (6,691.90). For LEA, the Logistic model was the most appropriate due to the results of R² (0.52), AIC (783.90), and BIC (798.40) obtained using this model. The absolute growth rates estimated using the von Bertalanffy and Logistic models for BW and LEA were 21.51g/d and 3.16 cm², respectively. The relative growth rates at the inflection point were 0.028 for BW (von Bertalanffy) and 0.014 for LEA (Logistic). Conclusion: The von Bertalanffy and Logistic models with random effect at the asymptotic weight are recommended for analysis of ponderal and carcass growth trajectories in New Zealand rabbits. The inclusion of random effects in the asymptotic weight and maturity rate improves the quality of fit in comparison to fixed models.

• Asian-Australasian Journal of Animal Sciences
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• 제27권7호
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• pp.974-980
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• 2014

In semi-arid areas of Southern Africa, dehydration can compromise the performance and welfare of local chickens, particularly during the growing period when confinement is curtailed and birds are left to scavenge for feed and water. The effect of water restriction on the growth performance was compared in Naked Neck (NNK) and Ovambo (OVB) chickens that are predominant in Southern Africa. A total of 54 eight-wk-old pullets each of NNK and OVB chickens with an initial average weight of $641{\pm}10g/bird$ were randomly assigned to three water intake treatments, each having six birds for 8 wk. The water restriction treatments were ad libitum, 70% of ad libitum and 40% of ad libitum intake. Nine experimental pens with a floor space of $3.3m^2$ per strain were used. The pens were housed in an open-sided house with cement floor deep littered with a 20 cm layer of untreated wood shavings. Feed was provided ad libitum. Average daily water intake (ADWI), BW at 16 weeks of age (FBW), ADG, ADFI, feed conversion ratio (FCR) and water to feed ratios (WFR) were determined. Ovambo chickens had superior (p<0.05) FBW, ADG and ADWI than NNK chickens. Body weight of birds at 16 weeks of age, ADG, ADFI, ADWI, and WFR declined progressively (p<0.05) with increasing severity of water restriction while FCR values increased (p<0.05) as the severity of water restriction increased. Naked Neck chickens had better FCR at the 40% of ad libitum water intake level than Ovambo chickens. The dressing percentage per bird was higher in water restricted birds than those on ad libitum water consumption, irrespective of strain. Heart weight was significantly lower in birds on 40% of ad libitum water intake than those on ad libitum and 70% of ad libitum water intake, respectively. In conclusion, NNK chickens performed better than OVB chickens under conditions of water restriction and would be ideal to raise for meat and egg production in locations where water shortages are a major challenge.

• Asian-Australasian Journal of Animal Sciences
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• 제17권9호
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• pp.1260-1265
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• 2004

This research was conducted to compare the effects of vitamin E (VE) when supplemented in either feed or water on the performance and meat quality of broilers. For a six-week feeding trial, a total of 330 broiler chicks were allotted to five treatments. The treatments were 1) 0 ppm VE, 2) 10 ppm VE in feed, 3) 20 ppm VE in feed, 4) 5 ppm VE in water and 5) 10 ppm VE in water. During the starter phase (0-3 weeks) chicks on non-supplemented groups grew slower (p<0.05) than the supplemented ones and the same trend was followed during the finisher (4-6 weeks) and overall period (0-6 weeks). The feed intake was significantly higher in feed supplemented groups as compared with water-supplemented groups and at higher levels as compared with lower levels of supplementation. The nutrient digestibility studies conducted after 15 and 35 days on the feeding trial showed that the digestibility of all nutrients was significantly (p<0.05) higher in supplemented groups than the non-supplemented one. The dressing percentage was higher in supplemented groups, when fed in feed and at higher levels when compared with their respective counterparts. Similar trends were noticed with respect to bone resistance. The calcium and phosphorus contents in tibia were also significantly (p<0.05) higher in supplemented, feed fed groups at higher levels than other groups. The TBARS values measured after 5 and 10 days of storage, which reflect the degree of oxidation, showed significantly lower levels in supplemented diets. The plasma and muscle vitamin E levels also showed a positive linear correlation with the levels supplemented both in feed and water. Overall it can be inferred that supplementation of VE was beneficial and there was not much difference observed when fed either in feed or water at the levels measured in the present study.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.23-23
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• 2017

Recent favor on high quality food and concern on food safety have demonstrated the superiority of Hanwoo (Korean native cattle). In general, the price of cow is higher than those of steer and bull, causing cheating issues in the market. Hence, this study is to discriminate genders of Hanwoo with identification of factors which highly influence gender discrimination based on the big-size deboning data. Totally, there were 31 variables in the deboning data, and we divided into them two categories: data obtained before and after deboning. Discriminant function analysis was then applied into the data to determined the accuracy of gender discrimination in Hanwoo. The result showed that Hanwoo could be classified by gender with 99.2% of accuracy when using all 31 variables. In detail, it was possible to identify 93 of 94 bulls (98.9%), 96 of 96 cows (100%) and 74 of 75 steers (98.7%). The most significant variables was chuck, sirloin, armbone shin, plates, retail and cuts percentage, sequentially. With variables obtainable before deboning, accuracies of classification were 91.5% for bulls, 92.7% for cows, and 89.3% for steers. The most significant variables was water, cold carcass weight and back-fat thickness. The discrimination accuracy was higher with data obtainable after deboning: bulls (98.9%), cows (99.0%) and steers (98.7%). In this case, chuck, sirloin and armbone shin were the factors determined the classification ability. This study showed that Hanwoo can be classified based on deboning data with appropriate statistics, further suggesting weight of cut of beef might be the standard for gender classification.

• Asian-Australasian Journal of Animal Sciences
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• 제31권7호
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• pp.933-950
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• 2018

In Japan, Wagyu cattle include four Japanese breeds; Black, Brown, Shorthorn, and Polled. Today, the renowned brand name Wagyu includes not only cattle produced in Japan, but also cattle produced in countries such as Australia and the United States. In recent years, the intramuscular fat percentage in beef (longissimus muscle) from Japanese Black cattle has increased to be greater than 30%. The Japanese Black breed is genetically predisposed to producing carcass lipids containing higher concentrations of monounsaturated fatty acids than other breeds. However, there are numerous problems with the management of this breed including high production costs, disposal of untreated excrement, the requirement for imported feed, and food security risks resulting from various viral diseases introduced by imported feed. The feeding system needs to shift to one that is more efficient, and improves management for farmers, food security for consumers, and the health environment for residents of Japan. Currently, we are developing a metabolic programming and an information and communications technology (ICT, or Interne of Things) management system for Wagyu beef production as future systems. If successful, we will produce safe, high-quality Wagyu beef using domestic pasture resources while solving the problems of how to utilize increasing areas of abandoned agricultural land and to make use of the plant-based feed resources in Japan's mountainous areas.

• Asian-Australasian Journal of Animal Sciences
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• 제21권10호
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• pp.1506-1515
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• 2008

Two feeding trials were conducted to assess the relative bioavailability (RBV) of methionine hydroxy analogue calcium salt (MHA-Ca) in comparison to DL-methionine (DL-Met). Male Ross 308 (1-38 days) and Cobb 500 chickens (1-42 days) were used in studies 1 and 2, respectively. Experimental diets based on wheat and soybean meal or sorghum and soybean meal were fed during three phases. In both experiments graded levels of DL-Met and MHA-Ca were supplemented to Met+Cys deficient basal diets. Additionally, in experiment 1, increasing levels of a DL-Met preparation diluted with corn starch to 65% purity (DL-Met65) were supplemented. Birds were kept in floor pens and feed and water were available ad libitum. Body weights and feed consumption were recorded at the beginning and end of the experimental periods and weight gain and feed efficacy were computed subsequently. At the end of the experiments, a number of birds were slaughtered for carcass evaluation (dressing percentage, breast meat yield). Dose response data were analysed by both ANOVA and nonlinear common plateau asymptotic regression. In both experiments birds responded significantly to increasing levels of either methionine source. However, RBV of MHA-Ca compared to DL-Met was markedly (in many cases significantly) below 84%, the value which would have been expected from MHA-Ca's chemical characteristics. Excluding some extremely low RBV figures of trial 2, RBV of MHA-Ca averaged to about 63% in relation to DL-Met. In addition, supplementation of DL-Met65 allowed confirmation of nonlinear common plateau asymptotic regression to be suitable to determine RBV.

• Asian-Australasian Journal of Animal Sciences
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• 제25권7호
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• pp.988-993
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• 2012

Four experimental diets were formulated to contain 700 g/kg cereal with decreasing levels of wheat:barley inclusion. Diet 1 contained 700 g/kg wheat, diet 2 contained 600 g/kg wheat and 100 g/kg barley, diet 3 contained 500 g/kg wheat and 200 g/kg barley and diet 4 contained 400 g/kg wheat and 300 g/kg barley. The diets were offered to pigs on three trials to investigate effects on the performance of individually (n = 72) and group housed (n = 480) pigs and on nutrient digestibility in pigs housed in metabolizm crates (n = 24). Performance was assessed from 10 wks of age until slaughter and carcass characteristics were measured. For the group performance study, one pig from each pen (in total 24) at 10, 15 wks and at finish were slaughtered to ascertain scores for stomach ulceration, stomach weights and intestinal length. Level of wheat inclusion did not significantly (p>0.05) affect liveweight gain (LWG) or feed conversion ratio (FCR). Feed intake was lowest (p<0.05) for individually housed pigs offered diets containing 700 g/kg wheat during the 10-15 wk period, which indicated that individually housed pigs attempted to eat to a constant energy intake. There was little evidence of stomach ulceration across treatments and increasing wheat inclusion had no detrimental effect. Higher levels of wheat inclusion tended to increase backfat depth at the $P_2$ position which could lead to increasing grading penalties in a commercial situation although more research is required in this area. Increasing level of wheat inclusion increased digestible energy (DE) content but the lack of effect on FCR and killing out percentage indicated that utilization of energy from barley and wheat was similar. Digestibility coefficients increased linearly with increasing wheat content, which can be attributed to the lower level of fibre and higher level of starch in wheat compared with barley.

• Asian-Australasian Journal of Animal Sciences
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• 제25권6호
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• pp.824-831
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• 2012

The objective was to compare meat quality, muscle fiber characteristics, lipid oxidation and fatty acids of Limousin (LIM), Simmtental (SIM), Luxi (LX), Qinchuan (QC) and Jinnan (JN) offered the same diet in China. After finishing, eight bulls from each breed were randomly selected for slaughter at 18.5 months old. Longissimus dorsi (ld) muscle was taken from the carcass for meat quality evaluations. Breed had little effect on most of meat and fat color parameters except for Hue and $b^*$ in which QC had lower values. LIM showed higher pH (24 h) and better water holding capacity than other breeds. LIM showed the lowest dry matter content but the highest crude protein. LX and LIM had higher percentage and density of red muscle fiber than other breeds. Lipid oxidations were significantly lower in LIM than in QC, with the LX, SIM and JN having the intermediate values. Compared to other four breeds, QC provided the highest values of polyunsaturated fatty acids (PUFA), n-6 fatty acids and n-3 fatty acids. In conclusion, LIM scored better on most of meat quality characteristics; however, local breeds such as LX and QC also had better muscle fiber characteristics and better fatty acids composition.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.203-208
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• 2006

This experiment was conducted to explore the efficacy of ${\alpha}$-tocopherol acetate (AT), a commercial supplement containing tocopherols, in commercial broilers. Three hundred and thirty Ross broiler chicks (4-d old) were randomly distributed and allotted to five dietary treatments for six weeks. Each treatment comprised 3 pens as replicates containing 22 chicks per pen. The five dietary treatments were: 0 mg/kg AT (negative control); 10 mg/kg AT; 50 mg/kg AT; 100 mg/kg AT; and 200 mg/kg AT; respectively, supplied totally by the supplement under study. Supplementation of AT improved weight gain significantly (p<0.05), with higher values in the 100 and 200 mg/kg AT fed group than the control during all phases of study, but feed intake remained unaffected. The nutrient digestibility studies conducted after 15 and 35 days of experimental feeding showed significantly higher digestibility of CP, ether extract and gross energy, in these two groups over the control diet. Carcass traits like dressing percentage and the color of the breast meat did not differ significantly due to treatments, but significantly (p = 0.0152) lower abdominal fat percent was noted in the 200 mg/kg fed group. Higher (p = 0.0003) tibia bone strength was noticed in groups fed diets above 50 mg/kg AT because of higher bone mineral content. The serum levels of tocopherols were not influenced but the muscle tocopherols content showed a positive linear trend with the dietary levels supplemented. The thio-barbituric acid reactive substances (TBARS) level in meat also suggested that supplemental AT has a protective role in rancidity. Overall, it could be concluded that AT supplementation at higher levels was found beneficial for growth and increased chicken meat quality.

• Asian-Australasian Journal of Animal Sciences
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• 제10권5호
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• pp.534-539
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• 1997

A uniform group of 12 upgrade grower goats of 6.0 -7.5 months old were used in this study. They were equally divided into three groups of $T_1$, $T_2$ and $T_3$ and were infected orally with three levels (0, 5,000 and 10,000 larvae) of infective Haemonchus contortus larvae. Before infection, all animals were housed in individual pens with concrete floor. They were provided with a uniform management. Comparison of body weight changes of infected and uninfected grower goats were done using weekly body weights. There was significant (p < 0.01) interaction between the effect of stomach worm infection and duration of infection on body weight. The infected groups (2 and 3) weighed significantly (p < 0.05) less than the control group from week 18 to 21. The animals of control group gained an average of 2.85 kg with 18.75 g average daily gain (ADG) in 152 days, which were significantly higher than those of animals in the infected groups. There was significant effect of H. contortus infection on the pres laughter weights of grower goats. The hot carcass weights of the infected goats were significantly lower than the uninfected group. No significant difference in dressing percentage of infected and uninfected groups was observed.