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971.
972.
Global Positioning System (GPS) tracking devices are a fundamental technology for quantifying the distribution and movement of livestock across landscapes. Although costs of GPS devices have decreased, it is still cost prohibitive to implement a large number of collars per study. Our objective was to develop and test a low-cost GPS collar using commercial off-the-shelf (COTS) electronic components to study livestock distribution and movement. Our COTS GPS tracker was built using the popular Arduino open-source microcontroller and a low-power timer board to cycle a GPS at defined intervals. Location data were saved to a data card in an open format for easy analysis. Total cost per COTS GPS device (including housing and collar) was $54.78. Average displacement from a known location and 95% circular error probability was 4.58 m, commensurate with other GPS collars. We tested durability and field performance of 25 COTS GPS collars against 24 existing GPS collars recording data at 5-min intervals in a southwest Idaho, United States study area. Our COTS GPS design and test showed that it is possible to manufacture low-cost location tracking devices, but the limitations of such devices must be considered relative to study objectives and duration. Low-cost location trackers will encourage collection of a higher density of location information to better understand patterns of livestock use in rangeland landscapes. 相似文献
973.
Maria Anete LALLO Lidiana Flora VIDOTO DA COSTA Anuska Marcelino ALVARES-SARAIVA Paulo Ricardo Dell’Armelina ROCHA Diva Denelle SPADACCI-MORENA Fabiana Toshie de Camargo KONNO Ivana Barbosa SUFFREDINI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):171-176
974.
A review of nutritional and toxicological implications of castor bean (Ricinus communis L.) meal in animal feeding systems
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T. O. Akande A. A. Odunsi E. O. Akinfala 《Journal of animal physiology and animal nutrition》2016,100(2):201-210
The nutrient‐rich defatted castor meal has been tested as a potential source of protein in diets of many livestock species but has limitation due to challenges of toxins. This review was conducted to compile the relevant research information on advances in the use of raw and differently processed castor seed meal in animal feed. In this article, distribution and uses of castor and its products were identified. Research findings on the nutrients profile, principal toxins, various detoxification strategies, nutritional value and toxicity on common livestock species were compiled and reviewed. The defatted seed meal had crude protein range of 32–48%, gross energy of about 3200 kcal/kg. Ricin content was 9.3 mg/g seed, and the average RCA content was 9.9 mg/g. The meal had high activity of lectin, which produced agglutination at about 4.70 mg/ml minimum assays. Reports of detoxification strategies showed varying degrees of success but high pH, moist heating and microbial techniques appeared to exert greater effect on deactivating ricin. Detoxification strategy for the allergen component is inconclusive. Tannins and the phenolic contents were present at trace level and did not constitute notable threat. It was concluded that castor seed holds great potential as feedstuff when upgraded but such upgrading must be safe, cost‐effective and labour efficient for commercial acceptability. 相似文献
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978.
《The Journal of Applied Poultry Research》2016,25(4):455-463
The discussions about the possibility of bacterial resistance resulting from the use of antimicrobial growth promoters in broiler feed. The limitations of international market have forced the exporting countries to search for alternatives to ensure the animal growth without affecting the quality of the final product. An experiment was conducted to evaluate the efficacy of in-feed CRINA® Poultry Plus (CPP, a mixture of benzoic acid and essential oils) in enhancing broiler growth performance and reducing coccidial lesions, as a non-antibiotic growth promoter. Effect of CPP on litter moisture content was also assessed. The treatments were: NC, a basal diet without growth promoters; PC, a basal diet with 10 ppm of Avilamycin (AVI); CPPD, a basal diet with 300 ppm of CPP from 1 to 42 d; AVI(1–21d)/CPP(22–42d), a basal diet with 10 ppm of AVI from 1 to 21 d and 300 ppm of CPP from 22 to 42 d; and AVI + CPP (1–42 d), a basal diet with 10 ppm of AVI and 300 ppm of CPP from 1 to 42 d. The 5 treatments were applied in a completely randomized arrangement and 10 replicate with 31 birds per pen. The diets with CPP increased body weight gain and feed conversion rates in the 1 to 42 d period and European productive efficiency index compared to birds fed with negative control diet (NC). Furthermore, lesion scores induced by E. acervulina were highest in the NC. The results suggest that CRINA® Poultry Plus can be used as an alternative to antibiotic growth promoters in broiler diets without losses in productive performance. 相似文献
979.
N. Szigetvari D. M. Imai C. M. Piskun L. C. S. Rodrigues E. Chon T. J. Stein 《Veterinary and comparative oncology》2016,14(3):225-235
Osteosarcoma is the most common primary malignancy of bone in dogs and is associated with poor long‐term outcomes due to its highly metastatic nature. A better understanding of the signalling pathways and proteins involved with osteosarcoma pathogenesis may aid in improved outcomes through the use of targeted therapies. The Wnt5a protein, a ligand for the non‐canonical Wnt signalling pathway, is implicated in mediating the aggressiveness of cancer cell lines, including those of human osteosarcoma origin. Given the close relationship between human and canine osteosarcoma, the primary goal of this study was to characterize Wnt5a expression in canine osteosarcoma. Second, if Wnt5a expression was present in canine osteosarcoma, the study aimed to determine any potential association with clinical outcome and clinical variables in similarly treated osteosarcoma‐bearing dogs. Wnt5a expression was present in 26 of the 48 (54%) cases of canine osteosarcoma. Wnt5a expression was not associated with progression‐free survival (P = 0.4) or overall survival (P = 0.1). 相似文献
980.
Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology – Veterinary (STROBE‐Vet) Statement
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