• Title/Summary/Keyword: Herd Size

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Taxonomic recognition of Saussurea maximowiczii var. triceps on Jejudo Island (한라분취의 분류학적 인식)

  • KIM, Byeol-Ah;SUN, Eun-Mi;YUN, Seon-Ah;KIM, Seung-Cheol;IM, Hyoung-Tak
    • Korean Journal of Plant Taxonomy
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    • v.48 no.1
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    • pp.24-36
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    • 2018
  • A morphological and molecular survey was conducted to determine the taxonomic status of Saussurea maximowiczii var. triceps on Jejudo Island. Although it tends to be smaller than S. maximowiczii with regard to typical quantitative characters of vegetative organs, including the plant height and leaf size, these two taxa cannot be distinguished from each other based on major reproductive characters, including the involucre and florets. Molecular data support the contention that S. triceps and S. maximowiczii are monophyletic taxa. Saussurea maximowiczii var. triceps is found to be an ecological phenotype of S. maximowiczii that has adapted particularly to the windy highlands of Hallasan Mountain on Jejudo Island.

Milk Quality and Antimicrobial Resistance against Mastitis Pathogens after Changing from a Conventional to an Experimentally Organic Dairy Farm

  • Suriyasathaporn, Witaya
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.5
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    • pp.659-664
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    • 2010
  • The present study was to investigate the effect of the transition from conventional to organic dairy farming on the antimicrobial resistant pattern of pathogens in milk. A farm with tie-stall management, with an average herd size of 20 milking cows, was selected based on the owner' willingness to accept, for at least 6 months, the highly restricted protocol developed in this study. Comparisons of bacterial isolates and antimicrobial susceptibilities before changing to an organic farm system (BEFORE) and for 6 months after (AFTER) operating the experimental organic farm system were performed by Fisher's Exact Chi-square tests. Significant levels were defined at p<0.05. During the AFTER period, average frequency of antibiotic treatment was decreased from more than 3 cases/month to less than 1 case/month during which the antibiotic use was authorized only by the veterinarian. In total, 92 and 70 quarter milk samples from 24 and 18 cows during BEFORE and AFTER, respectively, were included in the study. Overall, isolates ranged from a non-resistant level for cephazolin to a very high resistant level to streptomycin (64.71% to 95.45%). Percentages of antimicrobial resistant isolates during BEFORE were significantly higher than during AFTER for ampicillin (43.48% and 5.88%, respectively) and streptomycin (95.45% and 64.71%, respectively). In conclusion, percentages of antimicrobial resistant isolates were decreased after 6 months of operating as an organic farm system.

Prevalence of porcine group A, C rotavirus and calicivirus infections in the farm located in Incheon area (인천지역 돼지 혈청형 A, C 로타바이러스 및 칼리시바이러스 감염증 실태조사)

  • Jeong, Cheol;Ra, Do-Kyung;Kim, Kyoung-Ho;Han, Tea-Ho;Lee, Sung-Mo
    • Korean Journal of Veterinary Service
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    • v.34 no.2
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    • pp.125-131
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    • 2011
  • The present study was aimed to investigate the prevalence of porcine group A rotavirus, group C rotavirus and calicivirus from the 46 pig farms located in Incheon area. Group A rotavirus was detected in 16 (5.3%) from 8 farms (17.4%), and group C rotavirus was determined in 17 samples (5.7%) from 6 farms (13.0%). Porcine calicivirus was also detected in fecal samples [11 samples (3.7%) from 2 farms (4.3%)]. Correlation analysis was carried out among porcine enteric viruses and clinical signs, herd size and temperature on the basis of these results. The occurrence of porcine group A rotavirus, group C rotavirus and calicivirus infections in Incheon area was not associated with season and temperature. Especially, group C rotavirus was also detected in the pigs without any clinical symptoms.

Luzhong mutton sheep: inbreeding and selection signatures

  • Tao, Lin;He, Xiaoyun;Wang, Fengyan;Zhong, Yingjie;Pan, Linxiang;Wang, Xiangyu;Gan, Shangquan;Di, Ran;Chu, Mingxing
    • Journal of Animal Science and Technology
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    • v.62 no.6
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    • pp.777-789
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    • 2020
  • Intense artificial selection has been imposed to Luzhong mutton sheep population in the past years. Improvements on growth and reproductive performance are two breeding goals in the present herd. Although some progresses were phenotypically observed possibly due to inbreeding induced by strong selection in terms of these traits, the genomic evaluation was poorly understood. Therefore, a high-density SNP array was used to characterize the pattern of runs of homozygosity (ROH), estimate inbreeding and inbreeding depressions on early growth performance and litter size based upon ROH, and scan positive selection signatures of recent population. Consequently, a low inbreeding level was observed which had negative effects on litter size, but not on early growth performance. And 160 genes were under selection, of which some were reported to be linked to several traits of sheep including body weight, litter size, carcass and meat quality, milk yield and composition, fiber quality and health, and the top genes were associated with growth (growth hormone [GH]- growth hormone receptor [GHR]- Insulin-like growth factor 1 [IGF1] axis) and litter size (bone morphogenic proteins [BMPs]-associated). The effectiveness of previous breeding measures was highlighted, but purging selection was proposed to alleviate the inbreeding depression on litter size, providing some genomic insights to breeding management of Luzhong mutton sheep.

Study on Genetic Evaluation for Linear Type Traits in Holstein Cows

  • Lee, Deukhwan;Oh, Sang;Whitley, Niki C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.1
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    • pp.1-6
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    • 2010
  • The objectives of this study were to i) investigate genetic performance for linear type traits of individual Holstein dairy cows, especially focusing on comparative traits, and to estimate genetic variances for these traits using actual data, and ii) compare genetic performance and improvement of progeny by birth country of the cows. Linear type traits defined with five comparative traits on this study were general stature composite (GSC), dairy capacity composite (DCC), body size composite (BSC), foot and leg composite (FLC), and udder composite (UDC). These traits were scored from 1 to 6 with 1 = poor, 2 = fair, 3 = good, 4 = good plus, 5 = very good and 6 = excellent. Final scores (FS) were also included in this study. Data used was collected from the years 2000 to 2004 by the Korea Animal Improvement Association (KAIA). Only data of more than five tested cows by herd appraisal date and by sires having more than ten daughters were included to increase the reliability of the data analyses. A total of 30,204 records of the selected traits, which was collected from 26,701 individuals having pedigree information were used. Herd appraisal date, year of age, lactation stage (grouped by month), and time lagged for milking (in hours) were assumed as fixed effects on the model. Animal additive genetic effects considering pedigree relationship and residual errors were assumed with random effects. Year of age at appraisal date was classified from one to nine years of age, assigning the value of nine years of age for animals that were greater than or equal to nine years of age. From our results, the estimate for heritability was 0.463, 0.346, 0.473, 0.290, and 0.430 on GSC, DCC, BSC, FLC and UDC, respectively. The estimate for FS heritability was 0.539. The greatest breeding values for GSC were estimated for Canada, with the breeding values for American lines increasing for 10 years starting in 1989 but tending to decrease after that until 2004. For DCC, the breeding values for American and Canadian lines showed similar patterns until 1999, after which the breeding values for the American lines declined sharply. For BSC, data from Korea, Canada and the USA followed similar trends overall except when the breeding values of the American lines decreased starting in 1999. Overall, the methods used to evaluate genetic performance in this study were acceptable and allowed for the discovery of differences by country of genetic origin, likely due in part to the American use of selection indexes based primarily on milk yield traits until methods for evaluating other traits began to emerge.

Evaluation of Ascorbic Acid Treatment in Clinical and Subclinical Mastitis of Indian Dairy Cows

  • Naresh, Ram;Dwivedi, S.K.;Swarup, D.;Patra, R.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.6
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    • pp.905-911
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    • 2002
  • A study was carried out to assess the therapeutic effect of ascorbic acid in mastitis of dairy cows. The herd with a population of 250-275 lactating cows was screened for clinical and subclinical mastitis for a period of 5 months. Based on inclusion and exclusion criteria, eighteen animals each with clinical and subclinical mastitis in one quarter only were selected as study population. Twelve cows (group A) with normal udder and health were also selected as a healthy control. Clinical mastitis cows were grouped as B (n=12) and C (n=6). Cows of group B were treated with ascorbic acid at 25 mg/kg, subcutaneously for 5 consecutive days and intramammary infusion (Ampicillin sodium 75 mg and Cloxacillin sodium 200 mg/infusion) based on antibiotic sensitivity test, till complete recovery. Group C cows received only intramammary infusion till the complete recovery. Eighteen subclinical mastitis cows were divided in group D (n=12) and E (n=6). Cows of group D were treated with ascorbic acid at 25 mg/kg subcutaneously for 5 consecutive days while group E did not receive any treatment. California mastitis test (CMT), somatic cell count (SCC), physical changes of udder and milk were used to diagnose and classify the mastitis. Evaluation of the therapy was based on CMT score and physical changes of udder and milk. Sample size calculation was also performed but was not followed for control groups due to scarcity of cases. Adequate blinding was done when and where required to avoid the biases. Confounding variables like herd, age of the cow, stage of the lactation, season and geographical region were duly considered and adequate blocking was followed. Ascorbic acid was administered in clinical and subclinical cases even after cure considering its immunostimulatory and healing inducing effects. The recovery rate was faster in cases of clinical mastitis treated with ascorbic acid along with an intramammary infusion (group B) than the quarters of group C cows. Quarter wise the average duration/number (3.16${\pm}$0.11 days) of antimicrobial intramammary infusion was significantly (p<0.01) less in group B than that of average duration/number (5.33${\pm}$0.20 days) of group C. Subclinical mastitis cows treated with ascorbic acid showed 83.33% recovery while 16.77% did not respond to treatment till last day of study. Cows of group E (untreated) did not recovered from the mastitis. Subjective parameters viz. swelling, pain reflex of udder and physical changes in milk from quarter of ascorbic acid treated cows (group B) disappeared earlier than that of group C cows. It is concluded from this study that the ascorbic acid might be useful as an adjunct in case of clinical mastitis to get quick recovery with less number of intramammary infusions. High recovery rate in subclinical mastitis quarters of group D cows is appreciable and opens a new avenue to conduct further trials in a larger population in various field conditions. However, the pharmacology of ascorbic acid with particular reference to health of mammary gland needs to be investigated.

Characterization analysis of Rongchang pig population based on the Zhongxin-1 Porcine Breeding Array PLUS

  • Dong Leng;Liangpeng Ge;Jing Sun
    • Animal Bioscience
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    • v.36 no.10
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    • pp.1508-1516
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    • 2023
  • Objective: To carry out a comprehensive production planning of the existing Rongchang pig population from both environmental and genetic aspects, and to establish a closed population with stable genetic diversity and strict pathogen control, it is necessary to fully understand the genetic background of the population. Methods: We genotyped 54 specific pathogen free (SPF) Rongchang pigs using the Zhongxin-1 Porcine Breeding Array PLUS, calculated their genetic diversity parameters and constructed their families. In addition, we also counted the runs of homozygosity (ROH) of each individual and calculated the value of inbreeding coefficient based on ROH for each individual. Results: Firstly, the results of genetic diversity analysis showed that the effective population size (Ne) of this population was 3.2, proportion of polymorphic markers (PN) was 0.515, desired heterozygosity (He) and observed heterozygosity (Ho) were 0.315 and 0.335. Ho was higher than He, indicating that the heterozygosity of all the selected loci was high. Secondly, combining the results of genomic relatedness analysis and cluster analysis, it was found that the existing Rongchang pig population could be divided into four families. Finally, we also counted the ROH of each individual and calculated the inbreeding coefficient value accordingly, whose mean value was 0.09. Conclusion: Due to the limitation of population size and other factors, the genetic diversity of this Rongchang pig population is low. The results of this study can provide basic data to support the development of Rongchang pig breeding program, the establishment of SPF Rongchang pig closed herd and its experimental utilization.

Preparation and Management of Recipients in Bovine Embryo Transfer (수정란이식에 있어서 수란우의 준비와 관리)

  • 김창근
    • Journal of Embryo Transfer
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    • v.1 no.1
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    • pp.35-49
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    • 1986
  • Recipients are an integral part of embryo transfer and they are expensive to maintain as a good recipient. Recipient management is one of the most important components in a successful embryo transfer program. Management includes selection and subsequent care of the animals. A good recipient is basically on "open" cows or heffers whose reproductive tract is capable of receiving one or two embryos and incubating it to term. Potential recipients should be always be healthy and cycling normally ranging from 18 to 23 days. A thorough veterinary examination is recommended for candidate of recipients and cattle for questionable health should be eliminated from the recipient herd. Age and size of recipients are particularly important considerations when heifers are used, because of most embryos available for transfer are from large dams and sires. Body condition can influence a recipient's production, reproduction and health. Obese and underconditioned cattle should be avoided for use. Transfer of fresh embryos especially requires precise synchronization of donors and recipients. For estrus synchronization, PGF$_2$$\alpha$ is injected twice 10 to 12 days apart and short4erm progestagen treatment is applied to potential recipient cattle by coil into vagina (PRID) or ear implant (Synchro-Mate-B). The highest pregnancy results are achieved in recipients at exact synchrony with donors or 12 to 24 hr earlier than donors. Estrus detection is a major factor in breeding efficiency. High accuracy can be achieved by use of heat mount detection alds or by obserbing cattle for 30-minute peroids 3 times daily. Assay progesterone in milk can be used to discrIminate between pregnant and nonprenant recipients. Rectal palpation on day 35 to 70 after is an accurate and safe method of pregnancy diagnosis. Embryonic mortality in recipients may be associated with factors such as high environmental temperature and nutritional or lactational stress in early lactation period. Achievement of short calving interval requires concentrated management activity during the first 90 days following calving. Acceptable candidate for a recipient should be routinely vaccinated for infectious diseases. Proper nutritional programs according to NRC requirements and body condition scoring system for recipient cattles are vital to the ultimate success of an embryo transfer program.r program.

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Reproductive Performance of Three Iranian Sheep Breeds

  • Kiyanzad, M.R.;Panandam, J.M.;Emamjomeh Kashan, N.;Jelan, Z.A.;Dahlan, I.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.1
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    • pp.11-14
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    • 2003
  • To evaluate the ewe reproductive performances of three Iranian local sheep breeds, namely Moghani, Chal and Zel, 27 rams and 473 ewes were used as the foundation flock in a crossbreeding program. The three breeds were crossed amongst themselves reciprocally. Ram breed and ewe breed showed a two-way interaction on apparent fertility. The Zel ewes showed higher fertility than the Chal and Moghani ewes (94.4 vs 77.3 and 84.6%). Prolificacy among main and individual mating groups were not significantly different (p>0.05). Zel ewes were 22.3 and 14.8% more reproductive (p<0.05) than Chal and Moghani ewes, respectively. Zel and Moghani ewes showed higher (p<0.05) ewe productivity than Chal ewes. Ram breed had a significant (p<0.05) effect on ewe efficiency. The Zel rams were not completely successful to mate with Chal ewes, this caused a to way-interaction between ram and ewe breeds. The Zel ewes mated with Chal and Moghani rams showed 26.1 and 28.5% more efficiency than those mated with Zel rams. This observation strongly supports the use of crossbreeding to improve the efficiency of the Zel ewes. With decreasing lamb mortality, through supplemented feeding of lambs in pre-weaning period, and increasing litter weight, through crossbreeding, it should be possible to improve the efficiency of Zel ewes even better than Chal and Moghani ewes. Small body size of Zel ewes that needs the lower maintenance requirements would be a well advantageous to using Zel ewes as the dam herd to produce commercial lambs in north area of Iran.

Detection of the etiological viruses from calves with clinical diarrhea in Gyeongnam south area (경남 남부지방에서 송아지설사병 원인체 바이러스 검출 조사)

  • Heo, Jung-Ho;Cho, Myung-Heui;Lee, Kuk-Cheon;Park, Mi-Nam;Cho, Eun-Jeong;Choi, Man-Su;Kim, Chung-Hui;Kang, Joung-Boo;Kim, Eui-Kyung;Kim, Jong-Shu
    • Korean Journal of Veterinary Service
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    • v.31 no.3
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    • pp.265-272
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    • 2008
  • Among calves' diseases, digestive diseases most frequently occur in Korea, and especially viral diarrhea is one of the most important diseases. This study was conducted to get some basic information for the control of the viral diarrhea in calves. The samples were obtained from 319 calves with clinical diarrhea from 195 farms in Gyeongnam south area (Gosung, Tongyung, Hadong) from June 2005 to August 2006, Viral detection was examined by polymerase chain reaction (PCR), Etiological viruses were detected from 171(53,6%) of 319 calves, and bovine rotavirus (BRV) were 130 (40,8%) and bovine viral diarrhea virus (BVDV) 41 (12,9%), and no coronavirus was confirmed, Statistical difference was found in BRV detection between summer (32.6%) and winter (57.7%). However there was no seasonal difference in BVDV. In detection rate of the calves under 19days, BRV was highest (55.1%), but BVDV lowest (5.1%). No big difference was in rate among herd size. However, BRV was lowest (26.8%) in the group over 51 heads, but BVDV was highest (19.5%) in the same.