• Asian-Australasian Journal of Animal Sciences
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• 제29권11호
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• pp.1585-1592
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• 2016

The present experiment was conducted to evaluate the effect of simulated heat stress on digestibility and methane ($CH_4$) emission. Four non-lactating crossbred cattle were exposed to $25^{\circ}C$, $30^{\circ}C$, $35^{\circ}C$, and $40^{\circ}C$ temperature with a relative humidity of 40% to 50% in a climatic chamber from 10:00 hours to 15:00 hours every day for 27 days. The physiological responses were recorded at 15:00 hours every day. The blood samples were collected at 15:00 hours on 1st, 6th, 11th, 16th, and 21st days and serum was collected for biochemical analysis. After 21 days, fecal and feed samples were collected continuously for six days for the estimation of digestibility. In the last 48 hours gas samples were collected continuously to estimate $CH_4$ emission. Heat stress in experimental animals at $35^{\circ}C$ and $40^{\circ}C$ was evident from an alteration (p<0.05) in rectal temperature, respiratory rate, pulse rate, water intake and serum thyroxin levels. The serum lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activity and protein, urea, creatinine and triglyceride concentration changed (p<0.05), and body weight of the animals decreased (p<0.05) after temperature exposure at $40^{\circ}C$. The dry matter intake (DMI) was lower (p<0.05) at $40^{\circ}C$ exposure. The dry matter and neutral detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ compared to $25^{\circ}C$ and $30^{\circ}C$ exposure whereas, organic matter (OM) and acid detergent fibre digestibilities were higher (p<0.05) at $35^{\circ}C$ than $40^{\circ}C$ thermal exposure. The $CH_4$ emission/kg DMI and organic matter intake (OMI) declined (p<0.05) with increase in exposure temperature and reached its lowest levels at $40^{\circ}C$. It can be concluded from the present study that the digestibility and $CH_4$ emission were affected by intensity of heat stress. Further studies are necessary with respect to ruminal microbial changes to justify the variation in the digestibility and $CH_4$ emission during differential heat stress.

• Journal of Animal Science and Technology
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• 제58권4호
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• pp.14.1-14.9
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• 2016

Background: Peroxisome proliferator-activated receptor gamma (PPARG), CCAAT/enhancer binding protein alpha (CEBPA) and retinoid X receptor alpha (RXRA) are nuclear transcription factors that play important roles in regulation of adipogenesis and fat deposition. The objectives of this study were to characterise the variability of these three candidate genes in a mixed sample panel composed of several cattle breeds with different meat quality, validate single nucleotide polymorphisms (SNPs) in a local crossbred population (Angus - Hereford - Limousin) and evaluate their effects on meat quality traits (backfat thickness, intramuscular fat content and fatty acid composition), supporting the association tests with bioinformatic predictive studies. Results: Globally, nine SNPs were detected in the PPARG and CEBPA genes within our mixed panel, including a novel SNP in the latter. Three of these nine, along with seven other SNPs selected from the Single Nucleotide Polymorphism database (SNPdb), including SNPs in the RXRA gene, were validated in the crossbred population (N = 260). After validation, five of these SNPs were evaluated for genotype effects on fatty acid content and composition. Significant effects were observed on backfat thickness and different fatty acid contents (P < 0.05). Some of these SNPs caused slight differences in mRNA structure stability and/or putative binding sites for proteins. Conclusions: PPARG and CEBPA showed low to moderate variability in our sample panel. Variations in these genes, along with RXRA, may explain part of the genetic variation in fat content and composition. Our results may contribute to knowledge about genetic variation in meat quality traits in cattle and should be evaluated in larger independent populations.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.585-589
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• 1999

Six crossbred goats in their 2nd or 3rd lactation, were administered bromocryptine at 5 mg/day during early lactation of 15-20 days (period I) and thereafter again at an interval of 13 days, bromocryptine was given for 5 days (period II). Blood samples were collected before (-5, -4, -3, -2, -1) during (1, 2, 3, 4, 5) and after (+1, +2, +3, +4, +5) administration of bromocryptine in both the periods of study. In period I, administration of bromocryptine resulted in a decrease in milk yield to the extent of 16..8% in comparison to before treatment, and 28.5% after the cessation of treatment. The glucose content of blood increased (p<0.01) as the milk yield decreased without any change in NEFA concentration. During period II of bromocryptine treatment the milk yields did not change in spite of a decline in prolactin level, perhaps the effect of previous treatment was prolonged. A decline in protein and lactose content of milk after bromocryptine treatment in both the periods of study, when prolactin level also declined suggests a role of prolactin in protein synthesis and also a depressing effect on lactose synthesis.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1424-1431
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• 2016

The objective of this study was to evaluate the effect of diets containing different amounts of wheat, as a partial or whole substitute for corn, on digestibility, digestive enzyme activities, serum metabolite contents and ruminal fermentation in beef cattle. Four Limousin${\times}$LuXi crossbred cattle with a body weight ($400{\pm}10kg$), fitted with permanent ruminal, proximal duodenal and terminal ileal cannulas, were used in a $4{\times}4$ Latin square design with four treatments: Control (100% corn), 33% wheat (33% substitution for corn), 67% wheat (67% substitution for corn), and 100% wheat (100% substitution for corn) on a dry matter basis. The results showed that replacing corn with increasing amounts of wheat increased the apparent digestibility values of dry matter, organic matter, and crude protein (p<0.05). While the apparent digestibility of acid detergent fiber and neutral detergent fiber were lower with increasing amounts of wheat. Digestive enzyme activities of lipase, protease and amylase in the duodenum were higher with increasing wheat amounts (p<0.05), and showed similar results to those for the enzymes in the ileum except for amylase. Increased substitution of wheat for corn increased the serum alanine aminotransferase concentration (p<0.05). Ruminal pH was not different between those given only corn and those given 33% wheat. Increasing the substitution of wheat for corn increased the molar proportion of acetate and tended to increase the acetate-to-propionate ratio. Cattle fed 100% wheat tended to have the lowest ruminal $NH_3-N$ concentration compared with control (p<0.05), whereas no differences were observed among the cattle fed 33% and 67% wheat. These findings indicate that wheat can be effectively used to replace corn in moderate amounts to meet the energy and fiber requirements of beef cattle.

• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1563-1567
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• 2017

Objective: The influence of substituting steam-flaked corn (SFC) for dry rolled corn (DRC) on feedlot cattle growth performance and dietary net energy when cattle are allowed either ad libitum or 2-h restricted access to the finishing diet was evaluated. Methods: Treatment effects were tested using 96 crossbred steers ($251{\pm}2kg$) during the initial 56 d of the finishing phase. Cattle were blocked by weight and randomly assigned within blocks to 16 pens (4 pens/treatment). Bunk space was sufficient (41 cm/head) to allow all steers access to the feed bunk at the same time. Treatments consisted of two finishing diets containing (dry matter basis) 77.1% corn grain processed by dry rolling (density = 0.50 kg/L) or steam flaking (density = 0.36 kg/L). Cattle were fed twice daily at 06:00 and 14:00 h, allowing for approximately 5% residual. In the case of restricted feeding, steers were allowed access to feeders for 1 h following each feeding, after which residual feed was withdrawn. Results: There were no treatment interactions on dry matter intake (DMI), average daily gain (ADG), gain efficiency (G:F), or dietary net energy (NE). Restricting feed access time reduced (p<0.01) feed intake, and hence, ADG. Substitution of SFC for DRC increased (p<0.01) ADG, feed efficiency (G:F), and estimated dietary NE, without affecting DMI. Based on tabular net energy of maintenance ($NE_m$) value (2.18 Mcal/kg) for DRC, the estimated $NE_m$ value for SFC using the replacement technique, averaged 2.44 Mcal/kg; an improvement of 10.7%. The ratio of observed-to-expected dietary NE was not affected by feed access time. Conclusion: Substitution of SFC for DRC in finishing diets for feedlot cattle enhanced ADG, gain efficiency, and the NE value of the diet. Although restriction of feed access time depressed DMI and ADG, it did not affect the comparative benefit of steam flaking toward enhancement of ADG, G:F, and dietary NE.

• Animal Bioscience
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• 제35권1호
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• pp.29-38
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• 2022

Objective: The objective of this study was to compare the feeding value, meat nutrients and associative effects of a diet comprised of various corn silages inclusion with peanut vine or wheat straw in finishing beef cattle. Methods: One hundred and eighty Simmental crossbred beef steers were blocked and assigned to the follow treatments: i) whole plant corn silage-based diet (control, WPCS), ii) mixed forages-based diet (replacing a portion of corn silage with wheat straw, WPCSW), iii) corn stalklage-based diet (CS), and iv) sweet corn stalklage-based diet (SCS). Each group consisted of 5 repeated pens with 9 steers/pen. The diets were formulated to be isonitrogenous and isoenergetic with same forage to concentrate ratio. Experimental diets were fed for 90 d. Results: The effective ruminal degradability of dry matter and crude protein were highest for WPCS diet (p<0.05), for neutral detergent fiber was highest in SCS diet (p<0.05). The average daily gain was greater for cattle offered the WPCS diet, intermediate with WPCSW and SCS and lowest with CS (p<0.001). The concentration of non-esterified fatty acid in serum was higher for steers fed with CS and SCS diets than those offered WPCS and WPCSW steers (p<0.001). The treatments did not affect the general nutritional contents and amino acids composition of Longissimus dorsi of steers (p>0.05). Conclusion: The corn silage-based diet exhibited the highest feeding value. The sweet corn stalklage and wheat straw as an alternative to corn silage offered to beef cattle had limited influence on feeding value and meat nutrients. However, the value of a corn stalklage-based diet was relatively poor. To sum up, when the high quality forage resources, such as corn silage, are in short supply, or the growth rate of beef cattle decreases in the later finishing period, the sweet stalklage and wheat straw could be used as a cheaper alternative in feedlot cattle diet without sharp reducing economic benefits.

• Asian-Australasian Journal of Animal Sciences
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• 제18권1호
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• pp.22-26
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• 2005

Four male crossbred beef steers about 2 years old were used in a 4$\{times}$4 Latin square design to investigate the effect of pelleted sugarcane tops on voluntary feed intake, rumen fermentation and digestibility of nutrients. Experimental treatments were; Control (dried-chopped sugarcane tops (DCST)); PS1 (Pelleted sugarcane tops at 1 cm of diameter); PS2 (Pelleted sugarcane tops at 2 cm of diameter) and PS3 (Pelleted sugarcane tops at 3 cm of diameter). Roughage intake and total dry matter intake were 1.59, 1.62, 1.61, 1.63% BW and 2.09, 2.12, 2.11 and 2.13% BW in control, PS1, PS2 and PS3 treatments, respectively (p<0.05). Digestibility of DM, OM and CP were similar in control and PS3 treatment but there was significant difference (p<0.05) between control and PS1, PS2 treatments. Digestibility of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were 52.89, 50.01, 50.05 and 50.56% and 41.91, 39.96, 39.91 and 39.69% in control, PS1, PS2 and PS3, respectively (p<0.05). Total volatile fatty acids concentrations in rumen contents was 67.68, 65.93, 66.15 and 66.67 mM in control, PS1, PS2 and PS3, respectively (p<0.05). Even though, concentrations of acetate and butyrate (%) were significant different (p<0.05) but concentration of propionate (%) was not affected by treatments (p>0.05). Rumen pH, ammonia nitrogen and plasma urea nitrogen were significantly different (p<0.05) among treatments. From this experiment, it was found that dried-chopped sugarcane tops increased digestibility of nutrients whereas pelleted sugarcane tops increased feed intake in beef cattle. However, pelleted sugarcane tops at 3 cm of diameter did similar result in digestibility and rumen parameters with DCST. Therefore, it could be concluded that pelleting sugarcane top is an alternative way to improve the quality of sugarcane tops for use as ruminant roughage source.

• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.486-490
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• 1998

The present study examined the follicular populations prior to and during superovulation and investigated their relationship with superovulatory response in crossbred cattle. Eleven animals were administered i.m. 8 doses of Folltropin of 2.5 ml each (1.75 mg/ml) spread over 4 days beginning on Day 10 of oestrous cycle, and 30 and 20 mg Lutalyse was given alongwith the 5th and 6th injections of Folltropin, respectively, to induce luteolysis. The animals were artificially inseminated 48, 60 and 72 h after the first Lutalyse injection. The number of corpora lutea (CL) was recorded by palpation per rectum and embryos were recovered non-surgically on Day 6 (Day 0 day of superoestrus). The ovarian follicular population was examined by transrectal Ultrasonography 15 h prior to and 52 h after the first FSH injection, and then on the day of superoestrus and the day of flushing. The follicles were classfied on the basis of diameter as small (3-5 mm), medium (6-9 mm) and large (${\geq}10mm$). The total number of follicles increased significantly (p < 0.01) from $2.45{\pm}0.35$, 15 h prior to the first FSH injection to $8.09{\pm}1.12$, 52 h after the first FSH injection and then further to $13.27{\pm}1.89 $ on the day of superoestrus. A positive correlation was observed between the number of small follicles 15 h prior to the first FSH injection (r = 0.60, p < 0.05), the number of large follicles 52 h after the first FSH injection (r=0.59, p < 0.05) and the number of CL. The follicular population prior to and during superovulation was, however, not significantly different between high (> 6 CL) and low responders (${\leq}6CL$). The present study suggests that the follicular populations undergo dynamic changes during superovulation and that follicular populations prior to superovulation have a limited application as an indicator of the superovulatory response.

• Asian-Australasian Journal of Animal Sciences
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• 제28권9호
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• pp.1288-1295
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• 2015

In experiment 1, eighty crossbred steers ($239{\pm}15kg$) were used in a 229-d experiment to evaluate the effects of increasing levels of enzymatically hydrolyzed yeast (EHY) cell wall in diets on growth performance feedlot cattle during periods of elevated ambient temperature. Treatments consisted of steam-flaked corn-based diets supplemented to provide 0, 1, 2, or 3 g EHY/hd/d. There were no effects on growth performance during the initial 139-d period. However, from d 139 to harvest, when 24-h temperature humidity index averaged 80, EHY increased dry matter intake (DMI) (linear effect, p<0.01) and average daily gain (ADG) (linear effect, p = 0.01). There were no treatment effects (p>0.10) on carcass characteristics. In experiment 2, four Holstein steers ($292{\pm}5kg$) with cannulas in the rumen and proximal duodenum were used in a $4{\times}4$ Latin Square design experiment to evaluate treatments effects on characteristics of ruminal and total tract digestion in steers. There were no treatment effects (p>0.10) on ruminal pH, total volatile fatty acid, molar proportions of acetate, butyrate, or estimated methane production. Supplemental EHY decreased ruminal molar proportion of acetate (p = 0.08), increased molar proportion of propionate (p = 0.09), and decreased acetate:propionate molar ratio (p = 0.07) and estimated ruminal methane production (p = 0.09). It is concluded that supplemental EHY may enhance DMI and ADG of feedlot steers during periods of high ambient temperature. Supplemental EHY may also enhance ruminal fiber digestion and decrease ruminal acetate:propionate molar ratios in feedlot steers fed steam-flaked corn-based finishing diets.

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1040-1048
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• 1999

Four ruminally fistulated crossbred $(Sahiwal{\times}Holstein\;Friesan)$ adult (~6 yr.) cattle of about $318{\pm}16kg$ body weight were randomly assigned in an experiment based on $4{\times}4$ latin square design to study the effect of different level of barseem (Trifolium alexendrinum) supplementation to wheat straw based diet on intake, digestion, VFA production, eating behaviour and passage rate. Four dietary treatments were wheat straw ad lib. (I), supplementation to wheat either 15(II), 30(III) or 45(IV)% of berseem. Mean total volatile fatty acids (TVFA) concentration in rumen liquor was 58.45, 66.14, 77.92 and 78.64 mmol/l. TVFA concentration in rumen liquor increased significantly (p<0.01) with increased level of berseem supplementation upon 30% level of breseem. Two peaks of TVFA concentration was observed at 4 and 8 h post feeding. Brseem supplementation showed no significant effect on daily time spent for eating, ruminating or idling, chews per minute or number of rumination boli ingested per minute. Time spent for eating and ruminating one kg neutral detergent fibre (NDF) was significantly (p<0.05) less in breseem supplemented groups. Animals in groups I, II, III and IV consumed 26, 34, 47 and 57% of DM within 1st 4 h and 64, 70, 70 and 77% of total DM within 1st 8 h of offering. All the animals consumed more than 90% of their DMI within 12 h. Active period of rumination was observed 8h post feeding reached the peak at 16 h post feeding, then declined and animals spend considerable time idling in last 4 h of 24 h feeding cycle. Berseem supplementation showed no significant effect on eating and rumination time. It is concluded that berseem supplementation upon 30% increases the efficiency of chewing during eating and rumination, which results in increase intake and TVFA production and nutrient digestibility.