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1.
Heritability and genetic correlations between rumination time and production traits in Holstein dairy cows during different lactation phases 下载免费PDF全文
Riccardo Moretti Marcos Paulo Gonçalves de Rezende Stefano Biffani Riccardo Bozzi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(4):293-299
So far, rumination has been used as a proxy for monitoring dairy cow health at farm level. However, investigating its genetic aspects as well as its correlation with other important productive traits may turn this management tool into a new informative selection criterion. However, scientific evidences on genetic correlation among rumination time (RT) and milk production and milk composition are still scarce. Therefore, the objective of this study was to estimate the heritability of RT across three lactation phases and its genetic correlation with milk production, milk composition and somatic cell count (SCC). Results of our study showed that heritability for RT was 0.34 and was constant across lactation. The mean genetic correlations between RT and milk production and composition traits were 0.07 (milk production), ?0.07 (protein yield), ?0.31 (fat yield), and ?0.32 (fat/protein ratio). The mean genetic correlation between RT and the SCC was 0.05. 相似文献
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Bravo Carlo Millo Christian Covelli Stefano Contin Marco De Nobili Maria 《Journal of Soils and Sediments》2020,20(2):1074-1086
Journal of Soils and Sediments - Humic acids (HA) have several environmental roles, but are particularly important in aquatic environments, being recognized as redox active natural organic matter... 相似文献
3.
Piero ADDIS Alberto ANGIONI Viviana PASQUINI Angelica GIGLIOLI Valeria ANDREOTTI Stefano CARBONI Marco SECCI 《Integrative zoology》2021,16(2):138-148
Mussels close their shell as a protective strategy and the quantification of this behavioral marker may represent an alarm signal when they are exposed to environmental stressors. In the present study, we investigated the ability of the Mediterranean mussel Mytilus galloprovincialis to recover and then the resilience or inertia of valve activity after a pulsing exposition to diverse levels of salinity (5, 10, 20, and 35 PSU as reference value). The trial simulated an event of drastic and sudden reduction of seawater salinity thus mimicking an event of flash flood from intense rain. Valve gaping and movements were measured in continuous cycle for 10 days using a customized magneto-electric device which uses Hall sensors. Results showed that under normal conditions of salinity (35 PSU), the general pattern of valve movements was a continuously open state with sporadic spikes indicating a closing motion. At salinity of 5, PSU mussels reacted by closing their valves, leading to a 77% mortality on the 4th day. At salinity of 10, PSU animals were observed with closed valves for the entire duration of the exposure and no mortality occurred, they showed a significant reduction in the valve activity once the reference value of salinity was re-established. In contrast, salinity of 20 PSU did not trigger a significant behavioral response. Interestingly, there no define rhythms of valve movements were recorded during salinity challenges. 相似文献
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Detection of bacterial contamination and DNA quantification in stored blood units in 2 veterinary hospital blood banks 下载免费PDF全文
Valentina Stefanetti Arianna Miglio Katia Cappelli Stefano Capomaccio Elisa Sgariglia Maria L. Marenzoni Maria T. Antognoni Mauro Coletti Vittorio Mangili Fabrizio Passamonti 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(3):406-410
Blood transfusions in veterinary medicine have become increasingly more common and are now an integral part of lifesaving and advanced treatment in small and large animals. Important risks associated with transfusion of blood products include the transmission of various infectious diseases. Several guidelines suggest what infectious agents to screen for in canine and feline transfusion medicine. However, while the risk of bacterial contamination of blood products during storage and administration has not been documented in veterinary medicine, it has emerged as a cause of morbidity and mortality in human transfusion medicine. Clinical experience shows that the majority of blood component bacterial contaminations are caused by only a few species. Unlike other types of bacteria, psychrotolerant species like Pseudomonas spp. and Serratia spp. can proliferate during the storage of blood units at 4°C from a very low titer at the time of blood collection to a clinically significant level (> 105 CFU/mL) causing clinical sepsis resulting from red blood cell concentrate transfusions in human medicine. The purpose of this report was to describe the detection and quantification procedures applied in 4 cases of bacterial contamination of canine and feline blood units, which suggest the need for further investigations to optimize patients’ safety in veterinary transfusion medicine. 相似文献
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Eric Klaphake Ahmed Shoieb Ed Ramsay Juergen Schumacher Linden Craig 《Journal of zoo and wildlife medicine》2005,36(1):127-130
A 19-yr-old binturong (Arctictis binturong) with acute upper respiratory disease was euthanized. Postmortem findings included hepatocellular carcinoma, pancreatic islet cell carcinoma, and renal adenocarcinoma with metastasis to the spleen, pleura, and pericardium. A link between primary hepatic and renal neoplasms has been noted in older humans. 相似文献
8.
Henneguya pilosa sp. n., a new species of myxosporean from the gill filaments of the white piranha, Serrasalmus altuvei Ramirez, 1965 (Characidae), a freshwater teleost fish collected in the Zoological Garden of the city of Teresina (Piauí), Brazil, is described from light and transmission electron microscope observations. This myxosporean produced small plasmodia (up to 0.2 mm in diameter), each one containing all life-cycle stages of the parasite, including numerous spores. The spores, laterally compressed, averaged 54.2 (52.3-56.0) microm in total length and consisted of two unequal valves adhering together along the suture line and two caudal processes. The spore body measured 21.1 (20.0-23.1) microm in length, 5.9 (5.5-6.3) microm in width, and 2.2 (1.9-2.6) microm in thickness. The two equal ellipsoidal polar capsules of 7.4 (7.1-7.6) microm long and 1.2 (1.0-1.3) microm wide possessed a polar filament with 11-12 (rarely 13) turns. All surfaces of the spores were covered with a tightly adherent complex network of numerous densely ramified granulo-fibrillar masses, the longest measuring 1.5 microm long, observed around the caudal processes. The prevalence of infection was 30%. The taxonomic affinities of this parasite with other of the same genus in freshwater South American fish species are discussed. 相似文献
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Gilger BC Pizzirani S Johnston LC Urdiales NR 《Journal of the American Veterinary Medical Association》2003,222(3):343-5, 316
A hydroxyapatite orbital implant was used after enucleation of an eye from a 5-year-old performance horse. A custom-made corneoscleral prosthesis was made and fitted over the hydroxyapatite implant. The implant and surgery were well tolerated. Placement of a cosmetic prosthesis is desired after enucleation of equine eyes to allow horses to return to competition. Synthetic spheres consisting of methylmethacrylate or silicone have been used, although reported complications have included extrusion, infection, and poor cosmetic results. Hydroxyapatite orbital implants made from marine coral allow vascular and fibrous tissue growth from the host orbit into the implant, which decreases the possibility of implant extrusion or infection and allows enhanced healing of defects in the overlying conjunctiva. Extraocular muscle fixation onto the implant permits motility and assists in the prevention of implant extrusion. 相似文献