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941.
D. H. Roberts M. H. Lucas G. Wibberley D. Chasey 《Veterinary research communications》1980,4(1):301-305
The single intradermal comparative test was used with both avian and bovine tuberculin. Three cattle infected with bovine leukosis virus (BLV) were used as a source of infection. BLV-positive and susceptible animals were tuberculin tested alternately. Fifteen susceptible calves and 15 susceptible sheep were tested. A further three calves and three sheep were used as controls; the needles of the tuberculin syringes were deliberately contaminated with blood from the BLV-infected cattle, before being used in the test. Whereas all three calves and the three sheep inoculated intradermally with contaminated needles developed BLV infections, all of the other 30 animals have remained serologically negative to BLV for 10 months. Transmission of BLV with needles contaminated with BLV-infected blood was prevented by wiping the needles with absorbent cotton wool. 相似文献
942.
A.O. Latunde-Dada J.A. Bailey J.A. Lucas 《European journal of plant pathology / European Foundation for Plant Pathology》1997,103(1):35-41
The infection process of Colletotrichum destructivum, a cause of anthracnose in lucerne (= alfalfa, Medicago sativa) was studied by light microscopy. At the onset of the host-pathogen interaction, the fungus produced large, multilobed, multiseptate infection vesicles with elongated neck regions. Each infection structure packed the lumen of the initially-infected epidermal cell and remained confined within its walls for 48 h. Subsequently, narrow, invasive secondary hyphae radiated from the multilobed vesicles, grew through the walls of host cells and rapidly colonized the surrounding tissues. Acervuli emerged on the surface of colonized leaves 96 h after inoculation. These observations are discussed in relation to the infection process and specificity of a genetically closely-related isolate of Colletotrichum destructivum causing anthracnose in cowpea (Vigna unguiculata). 相似文献
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Lucas Machado Figueira Nadja Gomes Alves Ribrio Ivan Tavares Pereira Batista Viviane Lopes Brair Renato Ribeiro Lima Maria Emilia Franco Oliveira Jeferson Ferreira Fonseca Joanna Maria Gonalves Souza‐Fabjan 《Reproduction in domestic animals》2019,54(11):1493-1496
This study investigated the feasibility of applying fixed‐time (cryopreserved) embryo transfer in ewes. Embryos (n = 106) were non‐surgically recovered from superovulated donors (n = 39) on day 6–7 after oestrus. Straws containing one or two embryos (morulae and/or blastocysts) subjected to either slow freezing (SF, n = 62) or vitrification (VT, n = 44) were randomly used within fixed‐time embryo transfer on Day 8.5. Recipient ewes were nulliparous (n = 58) bearing corpora lutea after synchronous oestrous induction protocol. The pregnancy rate was higher (p = .03) in SF (39.4%) than VT (16.9%) and survival rate tended (p = .08) to be higher in SF than in VT (25.8% vs. 15.9%). Lambing rates were similar (p = .13) between SF (20.9%) and VT (15.9%). Embryos recovered by non‐surgical route after cervical dilation treatment and later cryopreserved by either slow freezing or vitrification produced reasonable pregnancy rates after FTET. 相似文献
945.
Lucas Pantaleon 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(2):356-362
A new strategy has been introduced in human health care, namely, achieving the best outcomes for the lowest cost and thus maximizing value for patients. In value‐based care, the only true measures of quality are the outcomes that matter to patients. When outcomes are measured and reported, it fosters improvement and adoption of best practices, thus further improving outcomes. Understanding outcomes is central in providing value and represents an opportunity for redefining veterinary patient care. Value is created by improving the outcomes of patients with a particular clinical condition over the full cycle of care, which normally involves multiple specialties and care sites. To be successful, a key aspect of value based care is working as teams (integrated practice units) centered around the patient's clinical condition. As veterinary medicine has become more specialized and more complex, multidisciplinary communication and trust among the care team are paramount in providing value to patients (and clients). Use of patient‐reported outcomes is an essential aspect for improving clinical care, because it enhances the connections among doctors and with patients. Designing and implementing owner‐reported outcomes in veterinary clinical practice will lead to an understanding of the effects of treatments on outcomes and quality of life (QOL) of our patients from the owner's perspective, a key way to assess a veterinary patient's QOL. 相似文献
946.
Genetic correlations between body weight,scrotal circumference and visual evaluation scores in Bos indicus cattle 下载免费PDF全文
Luíza R. A. Abreu Paulo G. M. A. Martins Lúcio F. M. Mota Talita A. Ferreira Virgínia M. P. Ribeiro Severino D. J. Villela Fernanda A. Merlo Aldrin V. Pires 《Animal Science Journal》2018,89(9):1223-1229
The objective was to estimate genetic correlations between body weight (BW), scrotal circumference and visual evaluation scores of body conformation measured at standard ages in Guzerat cattle. All measurements were performed at 205 (weaning age), 365, 450 and 550 days of age; for BW, two additional measurements (at birth and 120 days of age) were realized. The data utilized in this study were retrieved from a database of the Brazilian Association of Zebu Breeders that contained information of registered Guzerat animals born between 1970 and 2013. Genetic parameters were estimated in bi‐trait analyses by using Bayesian inference. Genetic correlations between BW at 205 and 450 days of age with other traits were high and positive, whereas the correlations between visual evaluation scores with other traits were moderate. Based on correlations herein obtained, we conclude that selection based on BW results in increased visual scores and scrotal circumference, leading to improvements in productive performance and animals with best body conformation. 相似文献
947.
T. Pinto-Correia N. Guiomar M.I. Ferraz-de-Oliveira E. Sales-Baptista J. Rabaça C. Godinho N. Ribeiro P. Sá Sousa P. Santos C. Santos-Silva M.P. Simões A.D.F. Belo L. Catarino P. Costa E. Fonseca S. Godinho C. Azeda M. Almeida M. Vaz 《Strength and Conditioning Journal》2018,71(5):612-625
Due to their complex structure and traditional low-intensity management, Portuguese oak woodland rangelands known as montados are often considered high nature value (HNV) farming systems, and as such, they may be deemed eligible for subsidies and incentives by governmental and nongovernmental agencies. Too little is known about how the HNV concept might be applied to conserve complex silvopastoral systems. These systems, due to their structural and functional complexity at multiple scales, tend to support high levels of biodiversity. Montados are in sharp decline as a result of the rapid specialization of land management that, through simplification, undermines multifunctionality. Understanding how changes in management influence these systems and their biodiversity is needed for prioritizing conservation efforts and for ensuring they remain HNV systems. On the basis of a field survey in 58 plots distributed among 29 paddocks on 17 farms, we conducted an integrated analysis of the relationship between grazing intensity and biodiversity in montados of similar biophysical and structural characteristics. Data on management were obtained through interviews, and biodiversity data (vegetation, macrofungi, birds, herpetofauna) were obtained through specific field protocols. Additional spatial data, such as soil characteristics, slope, land cover, and linear landscape elements, were also analyzed. The results show no overall biodiversity variation as a result of different management practices. However, different groups of species react differently to specific management practices, and within a pasture, grazing impacts are heterogenous. In low grazing intensity plots, macrofungi species richness was found to be higher, while bird species richness was lower. Using tree regeneration as proxy for montado sustainability, results show less tree regeneration in areas with higher forage quality and more intense grazing. Pathways for future progress are proposed, including creating areas within a paddock that attract grazing away from where regeneration is desired. 相似文献
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