• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.359-367
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• 2003

Supplementary feeding strategies were evaluated from pre-calving throughout lactation on 24 dual-purpose Mpwapwa breed cows in their second or greater lactation, weighing 246-455 kg. The Mpwapwa breed is an established breed of 4 Bos indicus breeds and 8% of Bos taurus. The cows were penned and stall-fed individually. Eight weeks before calving to eight weeks after calving, the cows were divided into two groups and offered hay ad libitum with either 2 kg DM (L) or 4 kg DM/day (H) concentrates. Nine weeks after calving half of the cows on L-level continued with 2 kg DM/day (L-L) while the remainder received 4 kg DM concentrate daily (L-H). Half of the cows on H-group continued with 4 kg DM/day (H-H) while the remainder received 2 kg DM/day (H-L). The concentrate mixture comprised of sunflower seed cake (33%) and maize bran (67%). The cows consumed all the concentrate offered. Hay DM intake was similar (6.8 kg/day) and tended to decrease the last two weeks before calving increased again after calving. Live weight change and body condition score were similar across treatments before calving but differed after calving (p<0.05). Heavier cows with higher condition score pre-calving had a higher body weight loss and regained weight later. After treatment reallocation, live weight change and condition differed between treatments (p<0.05). Calves were allowed to suckle milk from one quarter. The amount of milk suckled and calf weight gains were not significantly different between treatments. The cows were removed from the experiment when the milk yield was below 4 kg per day. Cows on treatment H produced 6.2 kg and on treatment L 5.0 kg saleable milk/day (p<0.05) during the first 8 weeks post partum. During the period 9-18 weeks post partum the saleable daily milk on H-H, L-H, H-L and L-L were 5.2, 4.8, 4.7 and 4.3 kg, respectively (p>0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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• pp.1121-1127
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• 2002

Sixteen crossbred (Bos indicus${\times}$Bos taurus) calves were randomly distributed in two groups (NP and LP) of eight calves each to study the effect of restricted (75%) protein supply on growth and immuno-biochemical response as an indicator of production and health of under-nourished animals during 3 to 9 months of age. The normal requirement of protein was provided to group NP and a less of 25% to group LP through calculated amount of concentrate and roughage in their daily ration. Assessment was made for weekly change in live weight, periodic alteration in blood metabolites and immunological status at six months of age in calves. An initial (during 3 to 6 months of age) depression (p<0.05) in growth was seen in low protein fed group (LP) compared to NP, which became non-significant in the later period of life (6 to 9 months of age). There was no significant effect on haemoglobin, total protein, albumin and globulin concentration except that of urea, which was decreased significantly (p<0.05) in animals fed on low protein diet ($19.83{\pm}1.25$ vs $25.93{\pm}1.29mg/dl$). The treatment effect that was seen in different periods of life was not uniform for other parameters except for urea, which showed a regular depression in LP compared to NP. The assessment of immunological status by indirect haemagglutination (IHA) test against Pasteurella multocida (P52 strain) was considerably (p<0.05) reduced in animals on LP ration compared to those on NP. It is thus argued that with poor nutrition (low protein) and state of compromised immunological response the production and health of the animals will be adversely affected.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1239-1244
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• 2000

In order to investigate the effect of incorporation of thermally processed cereal (maize) grain and differently degradable protein sources in the calf starter, twenty four newly born crossbred $(Bos\;taurus{\times}Bos\;indicus)$ calves were assigned at random to six diets in a $3{\times}2$ factorial design involving three protein sources viz. groundnut meal (GN), cottonseed meal (CS) and meat and bone meal (MB), each along with two differently processed grain, namely ground raw (R) and pressure cooked (P) maize. The corresponding calf starters with green oats (Avena sativa) were given free-choice from 14 d onwards till the end of the 90 d experimental feeding. A restricted milk diet was fed till the age of weaning at 60 d. Total DM intake was not affected by cereal or protein sources. However, daily intake of DM (59.23 vs 66.45 g) and CP (12.38 vs 14.10 g) per kg $W^{0.75}$ was reduced (p<0.05) due to cereal processing. Better (p<0.05) feed and protein efficiencies after weaning and during entire period in calves fed processed maize resulted in a trend of higher $(p{\leq}092)$ growth rate especially when GN was the source of protein. In comparison among protein sources, calves fed MB diets tended to grow faster $(p{\leq}098)$ concurrent with a higher CP intake before weaning. It is thus evident that thermal processing of maize in the calf starter seems to improve calf performance. Moreover, results indicated that feeding of protein and starch sources of matching ruminal degradability may prove beneficial for early growth of crossbred calves.

• Asian-Australasian Journal of Animal Sciences
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• 제31권11호
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• pp.1738-1746
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• 2018

Objective: The aim of the experiment was to assess the effect of increasing amounts of Leucaena leucocephala forage on dry matter intake (DMI), organic matter intake (OMI), enteric methane production, rumen fermentation pattern and protozoa population in cattle fed Pennisetum purpureum and housed in respiration chambers. Methods: Five crossbred heifers (Bos taurus${\times}$Bos indicus) (BW: $295{\pm}6kg$) were fed chopped P. purpureum grass and increasing levels of L. leucocephala (0%, 20%, 40%, 60%, and 80% of dry matter [DM]) in a $5{\times}5$ Latin square design. Results: The voluntary intake and methane production were measured for 23 h per day in respiration chambers; molar proportions of volatile fatty acids (VFAs) were determined at 6 h postprandial period. Molar concentration of VFAs in rumen liquor were similar (p>0.05) between treatments. However, methane production decreased linearly (p<0.005), recording a maximum reduction of up to ~61% with 80% of DM incorporation of L. leucocephala in the ration and no changes (p>0.05) in rumen protozoa population were found. Conclusion: Inclusion of 80% of L. leucocephala in the diet of heifers fed low-quality tropical forages has the capacity to reduce up to 61.3% enteric methane emission without affecting DMI, OMI, and protozoa population in rumen liquor.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1110-1115
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• 2005

To study the effect of feeding lactic acid producing bacteria on the performance of cattle calves, twenty four, day old male crossbred cattle calves (Bos indicus${\times}$Bos taurus), were distributed into two groups of 12 animals each. The animals were fed on calf starter containing wheat bran and green berseem ad libitum and milk as per requirement upto 8 weeks of age. The diet of calves of Group 2 was supplemented with 500 ml culture of Lactobacillus acidophilus-15. Total duration of the experiment was 31 weeks. There was no significant difference in intake and digestibility of dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF) and crude protein (CP) between the groups. The rumen pH, protozoa numbers, concentration of volatile fatty acids (VFA), ammonia nitrogen ($NH_3-N$), trichloroacetic acid precipitable nitrogen (TCA-ppt N) and activity of microbial enzymes (carboxymethylcellulase, xylanase, amylase and protease) were not affected due to probiotic supplementation. Average live weight gain of the calves was improved (about 10%) and feed:gain ratio was reduced (about 5%) in the animals given Lactobacillus culture. The data indicated that crossbred calves could be reared on a diet devoid of cereal grain and addition of Lactobacillus culture in the diet resulted in an added advantage in growth performance of the animals.

• 한국축산식품학회지
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• 제30권6호
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• pp.918-922
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• 2010

Due to the large amount of beef imported from the USA to Korea, Korean consumers have become increasingly interested in the country of origin since it can affect market prices. Previously, Bos indicus and Bos taurus-specific markers were developed for the purpose of cattle breed identification, specifically discrimination of Australian beef. In this study, six SNP markers derived from Illumina 50K bovine SNP chip data were used for the discrimination between Korean cattle (Hanwoo) and imported beef from USA. PCR-RFLP genotyping methods were also developed, which indicates that these markers can be applied relatively easily compared to other markers. Taking into account a discrimination rate of 55% based on MC1R marker between Hanwoo and imported beef from USA, two additional markers, SNPs 23803 and 34776, were ideal and resulted in probability of identification of 0.942 and probability of misjudgment of 0.03. Therefore, the markers developed in this study can greatly contribute to the correct discrimination between beef from USA and Hanwoo beef.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.141-158
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• 2020

Skin is a major thermoregulatory organ in the body controlling homeothermy, a critical function for climate adaptation. We compared genes expressed between tropical- and temperate-adapted cattle to better understand genes involved in climate adaptation and hence thermoregulation. We profiled the skin of representative tropical and temperate cattle using RNA-seq. A total of 214,754,759 reads were generated and assembled into 72,993,478 reads and were mapped to unique regions in the bovine genome. Gene coverage of unique regions of the reference genome showed that of 24,616 genes, only 13,130 genes (53.34%) displayed more than one count per million reads for at least two libraries and were considered suitable for downstream analyses. Our results revealed that of 255 genes expressed differentially, 98 genes were upregulated in tropically-adapted White Fulani (WF; Bos indicus) and 157 genes were down regulated in WF compared to Angus, AG (Bos taurus). Fifteen pathways were identified from the differential gene sets through gene ontology and pathway analyses. These include the significantly enriched melanin metabolic process, proteinaceous extracellular matrix, inflammatory response, defense response, calcium ion binding and response to wounding. Quantitative PCR was used to validate six representative genes which are associated with skin thermoregulation and epithelia dysfunction (mean correlation 0.92; p < 0.001). Our results contribute to identifying genes and understanding molecular mechanisms of skin thermoregulation that may influence strategic genomic selection in cattle to withstand climate adaptation, microbial invasion and mechanical damage.

• Genomics & Informatics
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• 제10권3호
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• pp.200-205
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• 2012

Although a large number of single nucleotide polymorphisms (SNPs) have been identified from the bovine genome-sequencing project, few of these have been validated at large in Bos indicus breeds. We have genotyped 192 animals, representing 5 cattle populations of Ethiopia, with the Illumina Bovine 8K SNP BeadChip. These include 1 Sanga (Danakil), 3 zebu (Borana, Arsi and Ambo), and 1 zebu ${\times}$ Sanga intermediate (Horro) breeds. The Hanwoo (Bos taurus) was included for comparison purposes. Analysis of 7,045 SNP markers revealed that the mean minor allele frequency (MAF) was 0.23, 0.22, 0.21, 0.21, 0.23, and 0.29 for Ambo, Arsi, Borana, Danakil, Horro, and Hanwoo, respectively. Significant differences of MAF were observed between the indigenous Ethiopian cattle populations and Hanwoo breed (p < 0.001). Across the Ethiopian cattle populations, a common variant MAF (${\geq}0.10$ and ${\leq}0.5$) accounted for an overall estimated 73.79% of the 7,045 SNPs. The Hanwoo displayed a higher proportion of common variant SNPs (90%). Investigation within Ethiopian cattle populations showed that on average, 16.64% of the markers were monomorphic, but in the Hanwoo breed, only 6% of the markers were monomorphic. Across the sampled Ethiopian cattle populations, the mean observed and expected heterozygosities were 0.314 and 0.313, respectively. The level of SNP variation identified in this particular study highlights that these markers can be potentially used for genetic studies in African cattle breeds.

• Asian-Australasian Journal of Animal Sciences
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• 제32권4호
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• pp.548-555
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• 2019

Objective: The main objective of this study was to evaluate the effect of different feeding levels of a total mixed ration silage-based diet on feed intake, total tract digestion, enteric methane emissions, and energy partitioning in two beef cattle genotypes. Methods: Six mature bulls (three Thai natives, and three Thai natives - Charolais crossbreeds) were assigned in a replicated $3{\times}3$ Latin square design, with cattle breed genotype in separate squares, three periods of 21 days, and three energy feeding above maintenance levels (1.1, 1.5, and 2.0 MEm, where MEm is metabolizable energy requirement for maintenance). Bulls were placed in a metabolic cage equipped with a ventilated head box respiration system to evaluate digestibility, record respiration gases, and determine energy balance. Results: Increasing the feeding level had no significant effect on digestibility but drastically reduced the enteric methane emission rate (p<0.05). Increasing the feeding level also significantly increased the energy retention and utilization efficiency (p<0.01). The Thai native cattle had greater enteric methane emission rate, digestibility, and energy utilization efficiency than the Charolais crossbred cattle (p<0.05). The daily metabolizable energy requirement for maintenance in Thai native cattle ($388kJ/kg\;BW^{0.75}$, where $BW^{0.75}$ is metabolic body weight) was 15% less than that in Charolais crossbred cattle ($444kJ/kg\;BW^{0.75}$). Conclusion: Our results suggested that the greater feeding level in zebu beef cattle fed above maintenance levels resulted in improved energy retention and utilization efficiency because of the reduction in enteric methane energy loss. The results also indicated higher efficiency of metabolisable energy utilization for growth and a lower energy requirement for maintenance in Bos indicus than in Bos taurus.

• Journal of Animal Science and Technology
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• 제44권2호
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• pp.181-190
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• 2002

본 연구는 한우 mt DNA 염기서열 가운데 $tRNA^{Pro}$와 $tRNA^{Pre}$ 유전자 사이에 위치하고 있는 D-loop 영역의 염기서열을 결정하고 한우의 염기변이 다형성을 분석하기 위하여 mt DNA의 D-loop 영역내 404번부터 15061까지 1142bp 크기의 염기서열 부위를 특이적인 primer를 이용하여 PCR로 증폭하였다. 한우의 mt DNA내 D-loop 영역에서 단일염기의 치환 및 삽입에 의해 총 24개의 polymorphic site가 확인되었다. 한우 mt DNA D-loop 영역 가운데 16042～16122번째에 위치하고 있는 영역의 염기치환율이 다른 염기서열 영역에 비하여 약 50%를 점유하고 있었으며 이들 polymorphic site에서 16055, 16230 및 16260 번의 염기치환은 한우에서만 검출된 새로운 염기변이로 확인되었다. 따라서, 한우 D-loop 영역내 특이적인 염기변이는 모계 및 세포질 DNA marker로서 한우품종을 특정하는데 활용할 수 있는 가능성을 시사하였다. Polymorphic site의 출현빈도는 169번째 염기가 81.3%로 가장 출현율이 높았고 다음으로 16302번과 16093번째는 56.3% 그리고 16042번와 16119번째 염기가 각각 50.0%와 43.8%의 치환율을 보였으며 나머지 14개 염기는 6.3%에서 25.0% 수준의 출현율을 나타냈다. 한우와 타 품종간의 유전적 근연관계를 추정한 결과 Bos taurus 계통의 유럽종과 유전적 유사도가 높은 것으로 추정되었고, Africa와 India의 Bos indicus 계통의 품종과는 상대적으로 근연관계가 먼 것으로 나타났다. 본 연구에서 검출한 mt DNA내 D-loop 영역의 염기서열 다형성은 한우집단의 유전적 변이성 추정과 모계유전 분석 및 나아가 경제적으로 중요한 형질들과의 연관성 분석에 유용하게 활용할 수 있을 것으로 기대된다.