• Asian-Australasian Journal of Animal Sciences
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• v.18 no.8
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• pp.1075-1079
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• 2005

The main objective of this study is to examine genetic changes in growth rate and carcass composition traits in group housed, ad libitum fed pigs, from lines of Large White divergently selected over four years for high and low post-weaning daily gain on a fixed but restricted ration. Genetic parameters for production and carcass traits were also estimated by using average information-restricted maximum likelihood applied to a multivariate individual animal model. All analyses were carried out on 1,728 records of group housed ad libitum fed pigs, and include a full pedigree of 5,324 animals. Estimates of heritability (standard errors in parentheses) were 0.11 (0.04) for lifetime daily liveweight gain (LDG), 0.13 (0.04) for daily carcass weight gain (CDG) and 0.28 (0.06) for carcass backfat (CFT). Genetic correlations between LDG and CDG were highly positive and between LDG and CFT negative, suggesting that selection for lifetime daily gain under commercial conditions of group housing with ad libitum feeding would result in favourable improvement in carcass traits. CFT showed negative genetic correlations with CDG. Correlated genetic responses evaluated as estimated breeding values (EBVs) were obtained from a multivariate animal model-best linear unbiased prediction analysis. After four years of divergent selection for 6 week post-weaning growth rate on restricted feeding, pigs performance tested on ad libitum feeding in groups exhibited changes in EBVs of 6.77 and -9.93 (g/d) for LDG, 4.25 and -7.08 (g/d) for CDG, and -1.42 and 1.55 (mm) for CFT, in the high and low lines, respectively. It is concluded that selection for growth rate on restricted feeding would significantly improve genetic performance and carcass composition of their descendants when group housed and ad libitum fed as is a common commercial practice.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.86-90
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• 2006

This study was carried out to determine the effects of free choice feeding of starter feed and whole cereals on the growth of turkey poults. Two hundred-seventy poults (7-d old) were divided into 3 treatment groups each with 3 replications containing 15 males and 15 females. Control poults (C) were fed only on starter feed (280 g CP and 11.7 MJ ME/kg). Treatments for choice-fed turkey poults were offered a choice of a starter feed and wheat (120 g CP and 12.3 MJ ME/kg) for wheat selecting (WS) or maize (83 g CP and 13.9 MJ ME/kg) for maize selecting (MS) group in separate feeders. Final live weight (2,280.7 g for the C vs. 2,374.3 and 2,324.6 g for the WS and MS), daily gain (39.21 g vs. 40.87 and 39.99 g) and total feed intake (95.2 g vs. 103.2 and 97.9 g) in the WS poults were significantly higher (p<0.05) than those of the C group, but feed conversion ratio was not significantly different between the treatments. The proportional intakes of cereals vs. total feed intake were 11% in both the WS and MS group. The amount of protein intake in the C group (280 g CP/kg diet) was significantly (p<0.05) higher than that in WS and MS groups (263 and 259 g CP/kg diet, respectively) whilst the ME intake in the C group (11.7 MJ/kg diet) was significantly (p<0.05) lower than that in MS group (11.9 MJ/kg diet). Our results showed that turkey poults fed starter feed and whole wheat in a free choice feeding system have a higher efficiency in terms of daily gain, final live weight, and an economic advantage may be obtained from free choice feeding due to a reduced protein intake and feed cost.

• Animal Bioscience
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• v.34 no.1
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• pp.85-92
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• 2021

Objective: The objectives of this study were to determine the in situ degradation parameters and appropriate feeding level of pineapple cannery by-products (PCB) based on the growth performance and blood parameters of growing Hanwoo (Bos taurus coreanae) steers fed various levels of PCB. Methods: Two ruminally cannulated Holstein cows were used for in situ disappearance rate measurements. Nylon bags (5×10 cm, 45 ㎛ pore size) filled with 5 g of PCB in triplicate were inserted into the ventral sac of the two cannulated Holsteins cows and incubated for 0, 2, 4, 8, 16, 24, and 48 h. A total of 16 castrated growing Hanwoo steers (12.5±0.5 months old, 302.9±25.7 kg of initial body weight [BW]) were used for the experiment. Animals were stratified by initial BW and then randomly assigned to one of four experimental diets (0%, 1.5%, 3.0%, or 6.0% of PCB, on the dry matter [DM] basis) fed for 91-d, including 30-d of adaptation. Results: Soluble fraction a of DM and crude protein (CP) was 61.9% and 86.0%, fraction b of DM and CP was 32.7% and 11.2%, and indigestible fraction c of DM and CP was 5.4% and 2.8%. The 6.0% PCB feeding group showed lower productivity compared to animals in the other treatments. Increasing the dietary level of PCB did not alter DM intake, but it was numerically lowest in the 6.0% feeding group. The gain to feed ratio was linearly decreased by increasing of PCB. The quadratic broken-line test estimated that 2.5% (DM basis) was the maximum feeding level of PCB in growing Hanwoo steers (y = 0.103 - 0.001×[1.245-x]2, R2 = 0.18). Conclusion: Diets containing up to 2.5% PCB can be fed to growing Hanwoo steers without adverse effects on growth performance.

• Animal Bioscience
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• v.34 no.2
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• pp.233-242
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• 2021

Objective: The aim of this study was to determine the effect of pineapple cannery by-product (PCB) level on the growth performance and carcass characteristics of finishing Hanwoo steers. Methods: The feeding stage was divided into early and late finishing stages. A total of 60 castrated Hanwoo steers (13.9±0.8 months old, 418.8±36.5 kg initial body weight [BW]) were blocked by initial BW and then randomly allotted into 12 pens (five head/pen). The pens were randomly assigned to control (CONT), low PCB (LPCB), or high PCB (HPCB) treatments. These diets contained 0%, 1.5%, or 3.0% of PCB (on a dry matter [DM] basis; as-fed basis was 0%, 10.6%, or 21.2%), respectively. Results: For the early finishing stage, body weight gain (BWG) and average daily gain (ADG) of the CONT and LPCB feeding groups were greater (p<0.05) than those of the HPCB feeding group. In addition, there were linear and quadratic effects on BWG and ADG with increasing dietary PCB level (p<0.05). The gain to feed (G:F) ratio tends to quadratically decrease with an increasing PCB level in the early finishing stage (p = 0.076). Growth performances of late finishing stage were not affected by PCB level. The marbling score of the LPCB feeding group was similar to that of the CONT feeding group. However, there was a linear decrease (p< 0.05) in marbling score and quality grade among treatments as PCB was increased in the diet. In the longissimus muscle free amino acid profile, histidine composition increased linearly (p<0.05) with an increasing level of PCB. Conclusion: The level of PCB 1.5% DM in diet can be used for finishing steers without any adverse effects on growth and carcass performances. However, there were some negative effects on growth and carcass performance in the HPCB feeding group.

• Animal Bioscience
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• v.36 no.11
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• pp.1655-1665
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• 2023

Objective: The aim of this study was to evaluate the effects of three feeding systems, i.e., indoor feeding (CON), indoor feeding with 4-h daily access to grazing artificial pasture (ITGP), and indoor feeding with 8-h daily access to grazing artificial pasture (IEGP), on the plasma antioxidant and immunological capacity, slaughter characteristics, meat quality and economic efficiency of Huang-huai lambs. Methods: Thirty-three healthy Huang-huai rams with similar body weight (approximately 5 mo of age, 28.96±1.01 kg) were assigned equally to three experimental groups. When finished fattening, six lambs from each group were collect blood samples for plasma analyses and then slaughtered to determine slaughter characteristics and obtain biceps brachii muscle for further analysis of meat quality and fatty acid profile. Results: Compared to CON group, animals submitted to ITGP and IEGP groups resulted in greater contents of serum glutathione peroxidase, immunoglobulins (IgA, IgG, and IgM), polyunsaturated fatty acids (PUFA), n-6 PUFA, and PUFA/saturated fatty acid (FA) ratio and lower palmitic /oleic acid ratio (p<0.05). Moreover, animals in ITGP group exhibited a higher (p<0.05) loin eye area, content of meat crude protein (CP), and eicosetrienoic acid compared to CON group, while slaughter performance was superior (p<0.05) to that of the IEGP group. The economic efficiency of ITGP group was 70.12% higher than that of CON group, while the IEGP group exhibited a decrease of 92.54% in economic efficiency compared to the CON group. Conclusion: Restricted grazing time combined with indoor feeding was more effective in conferring superior body health, carcass traits and economic efficiency in Huang-huai lambs, as well as higher CP content and healthier FA composition in the resulting meat.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.204-213
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• 2008

Four ruminally cannulated Holstein cows averaging 43 days in milk (DIM) were used in a $4{\times}4$ Latin square to determine the effect of feeding extruded soybean, ground canola seed and whole cottonseed on ruminal fermentation and milk fatty acid profile. One hundred and twenty lactating Holstein cows, 58 (${\pm}31$) DIM, were assigned to four treatments in a completely randomized block design to study the effects of the three types of oilseeds on production parameters and milk fatty acid profile. The four diets were a control diet (CON) and three diets in which 10% extruded soybean (ESB), 5% ground canola seed (GCS) and 10% whole cottonseed (WCS) were included, respectively. Diets consisted of concentrate mix, corn silage and Chinese wild rye and were balanced to similar concentrations of CP, NDF and ADF. Ruminal fermentation results showed that ruminal fermentation parameters, dry matter intake and milk yield were not significantly affected by treatments. However, compared with the control, feeding cows with the three oilseed diets reduced C14:0 and C16:0 and elevated C18:0 and C18:1 concentrations in milk, and feeding ESB increased C18:2 and cis9, trans11 conjugated linoleic acid (CLA). Production results showed that feeding ESB tended to increase actual milk yield (30.85 kg/d vs. 29.29 kg/d) and significantly decreased milk fat percentage (3.53% vs. 4.06%) compared with CON. Milk protein (3.41%) and solid non-fat (13.27%) from cows fed WCS were significantly higher than from cows fed CON (3.24% and 12.63%, respectively). Milk urea N concentrations from cows fed the ESB (164.12 mg/L) and GCS (169.91 mg/L) were higher than cows fed CON (132.31 mg/L). However, intake of DM, 4% fat corrected milk, energy corrected milk, milk fat and protein yields, milk lactose percentage and yield, somatic cell count and body condition score were not affected by different treatments. The proportion of medium-chain fatty acid with 14 to 16 C units in milk was greatly decreased in cows fed ESB, GCS and WCS. Feeding ESB increased the concentration in milk of C18:1, C18:2, C18:3 and cis9, trans11-CLA content by 16.67%, 37.36%, 95.24%, 72.22%, respectively, feeding GCS improved C18:0 and C18:1 by 17.41% and 33.28%, respectively, and feeding WCS increased C18:0 by 31.01% compared with feeding CON. Both ruminal fermentation and production trial results indicated that supplementation of extruded soybean, ground canola seed and whole cottonseed could elevate the desirable poly- and monounsaturated fatty acid and decrease the medium chain fatty acid and saturated fatty acid content of milk fat without negative effects on ruminal fermentation and lactation performance.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.334-347
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• 2000

The present experiment was carried out to study the utilization of glucose in the mammary gland of crossbred Holstein cattle during feeding with different types of roughage. Sixteen first lactating crossbred Holstein cattle which comprised eight animals of two breed types, Holstein Friesian${\times}$Red Sindhi ($50{\times}50=50%$ HF) and Holstein Friesian${\times}$Red Sindhi ($87.5{\times}12.5=87.5%$ HF). They were divided into four groups of 4 animals each of the same breed. The utilization of glucose in the mammary gland was determined by measuring rates of glucose uptake and the incorporation of glucose into milk components in both groups of 50% HF and 87.5% HF animals feeding on either hay or urea treated rice straw. In early lactation, there were no significant differences of the total glucose entry rate and glucose carbon recycling among groups of crossbred animals feeding on either hay or urea treated rice straw. During lactation advance, the total glucose turnover rates and recycling of carbon glucose of crossbred HF animals feeding on urea treated rice straw were markedly higher than those of crossbred HF animals feeding on hay as roughage, whereas there were no significant changes for both groups of crossbred animals feeding on hay. The percentages and values of non-mammary glucose utilization showed an increase during lactation advance in the same group of both 50% HF and 87.5% HF animals. The percentage of glucose uptake for utilization in the synthesis of milk lactose by the mammary gland was approximately 62% for both groups of 87.5% HF and by approximately 55% for both groups of 50% HF animals feeding on either hay or urea treated rice straw. Intracellular glucose 6-phosphate metabolized via the pentose phosphate pathway accounted for the NADPH (reducing equivalent) of fatty acid synthesis in the mammary gland being higher in 87.5% HF animals during mid-lactation. A large proportion of metabolism of glucose via the Embden-Meyerhof pathway in the mammary gland was more apparent in both groups of 50% HF animals than those of 87.5 % HF animals during early and mid-lactation while it markedly increased for both groups of 87.5% HF animals during late lactation. It can be concluded that utilization of glucose in the mammary gland occurs in a different manner for 50% HF and 87.5% HF animals feeding on either hay or urea treated rice straw. The glucose utilization for biosynthetic pathways in the mammary gland of 50% HF animals is maintained in a similar pattern throughout the periods of lactation. A poorer lactation persistency in both groups of 87.5% HF animals occurs during lactation advance, which is related to a decrease in the lactose biosynthetic pathway.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.9
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• pp.1267-1272
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• 2002

The present research was undertaken to monitor the effects of restricted and ad. libitum feeding during last trimester of pregnancy on the performance of crossbred dairy cows and their calves. For this purpose two groups of crossbred cows having eight animals in each group were put into two plane of nutrition during their last three months of pregnancy. Dietary energy level in one group was calculated as per Ministry of Agriculture, Fisheries and Food, (MAFF, UK) and the cows on other group received ad. libitum feeding (concentrate level similar to MAFF, recommendation+ad. libitum roughage). After calving, the cows of both groups were given same diet (ad. libitum) to study the effect of feeding during pregnancy on subsequent lactation performance of the cows. It was observed that during pre-calving period cows on ad. libitum feeding gained significantly (p<0.05) more body weight than that of cows on restricted feeding ($38.50{\pm}6.04$ vs $21.37{\pm}8.04kg/cow$). There was no significant differences between the birth weight of calves of restricted ($21.31{\pm}2.18kg$) and ad. libitum ($20.31{\pm}3.27kg$) groups. Dietary energy intake of ad. libitum group ($50.22{\pm}4.24$ MJ ME/d/cow) was significantly higher (p<0.01) than that of restricted group ($39.76{\pm}1.03$ MJ ME/d/cow). During lactation period cows that were on restricted feeding produced little more milk (3.06 lit/cow/day), than that of the cows on ad. libitum feeding (2.84 lit/cow/day). Although growth rate of the calves of restricted group upto one month ($0.23{\pm}0.09kg/calf/d$) was significantly (p<0.01) higher than that of ad. libitum group ($0.17{\pm}0.08kg/calf/d$) but after four months the growth rate of the calves of two groups become nearly similar ($0.35{\pm}0.02$ vs $0.37{\pm}0.03kg/calf/d$) and difference between them was non-significant. During lactation period cows of restricted group gained little weight but cows of ad. libitum group lost significantly (p<0.05) more weight. Per day metabolizable energy intake in both group during lactation period was nearly similar (67.54 vs 69.58 MJ ME). It is concluded that ad. libitum feeding during last trimester of pregnancy is neither economic for getting maximum milk yield nor for calf growth rate and MAFF, recommended level of dietary energy during that period could be applied on our pregnant crossbred dairy cows.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.12
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• pp.1683-1689
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• 2001

The levels of urea nitrogen both in blood (BUN) and milk (MUN), and milk protein (MP) reflect protein and energy intake in dairy herd feeding. Blood and milk constituents may be changes rhythmically and influence by different sampling time within a day and after feeding. Trials were conducted using five dietary treatments in both lactating and dry cows to study the effects of sampling time on concentrations of BUN, MUN and whole blood ammonia nitrogen (BAN) in practical dairy cow feeding in Taiwan. The conventional feed ingredients and forages including corn silage, alfalfa hay, timothy or pangola hay and corn grain were used as major source of the diet to follow practical dairy cow feeding. Five different diets were varying in amounts (low=L; standard=S; high=H) of crude protein (P) and energy (E) according to the NRC (1989). The energy to protein ratios in kcal/kg for the PSES, PLES, PHES, PSEH and PSEL were 10.82, 12.54, 9.41, 12.53 and 9.13 in lactating cows, and 11.38, 13.33, 9.78, 13.28 and 9.74 in dry cows, respectively. Results showed that after feeding at 9:30, BUN reached peak at 13:30 and was significantly higher than those to that sampled at 14:30 to 18:30 (p<0.05) in dry cows. Therefore the best blood sampling time for urea nitrogen assay in dry cows is 4 hours after morning feeding. In lactating cows, BUN of 13:30 was significantly higher than those of 8:30 to 11:30 (p<0.05), but there were no significant difference between the BUN values of other sampling time. Hence the suitable blood sampling time for BUN value in lactating cows was located on 3 to 8 hours after morning feeding, but the best time was 4 hours after morning feeding. MUN content is significantly higher in the afternoon collected bulk milk than the fore-strip morning milk (p<0.05), therefore the best sampling time for MUN is from afternoon collected bulk milk. Diurnal BAN changed without traceable rhythmic pattern and was negatively correlated to the BUN (r = -0.78). It is suggested that BAN may not be a good indicator for monitoring dairy cow feeding.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.8
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• pp.1069-1085
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• 2011

In large-type goats that were fed on dry forage twice daily, dry forage intake was markedly suppressed after 40 min of feeding had elapsed. The objective of this study was to clarify whether or not increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding suppress dry forage intake. Eight large-type male esophageal- and ruminal-fistulated goats (crossbred Japanese Saanen/Nubian, aged 3 to 6 years, weighing $72.3{\pm}2.74$ kg) were used in two experiments conducted under sham feeding conditions. The animals were fed ad libitum a diet of roughly crushed alfalfa hay cubes for 2 h from 10:00 to 12:00 h during two experiments. Water was withheld during feeding in both experiments but was available for a period of 30 min after completion of the 2 h feeding period. In experiment 1, an intraruminal infusion of artificial parotid saliva (RIAPS) in the control replenished saliva lost via the esophageal fistula and an intraruminal infusion of hypertonic solution (RIHS) in the treatment was carried out in order to reproduce the effects of changing salt content due to feed entering the rumen. In experiment 2, the RIHS control was conducted in the same manner as the RIHS treatment of experiment 1. The treatment group consisted of RIHS-with an intravenous infusion of artificial mixed saliva (VIAMS) treatment that was carried out for 3 h to prevent increases in plasma osmolality during feeding. The results of the RIHS treatment in experiment 1 showed that ruminal fluid osmolality increased and then an increase in plasma osmolality was observed. This resulted in the production of thirst sensations and the reduction of cumulative dry forage intake to 43.3% (p<0.05) of the RIAPS control. The results of the RIHS-VIAMS treatment in experiment 2 indicated that ruminal fluid osmolality was the same as the RIHS control but plasma osmolality significantly decreased, and thirst level was markedly reduced. This caused a significant increase of 31.4% (p<0.05) in cumulative dry forage intake in the RIHS-VIAMS treatment compared to the RIHS control. These results indicate that increases in ruminal fluid osmolality during dry forage feeding indirectly suppresses dry forage intake by causing an increase in plasma osmolality and subsequently inducing thirst sensations. The results of the present study suggest that marked decreases in dry forage intake after 40 min of feeding are caused by increases in plasma osmolality and subsequent thirst sensations produced by dry forage feeding.