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41.
Disease outbreaks characterized by reproductive failure and/or neurologic disorders, which are commonly referred as "Porcine Reproductive and Neurologic Syndrome (PRNS)", were observed in many swine farms in Iowa and other states. Although an infectious cause was suspected to account for the disease, no conclusive diagnosis had been reached with respect to conventional infectious agents. Extensive laboratory diagnostic investigation on suspect cases repeatedly resulted in the isolation of a cytopathic enveloped virus of 50-60nm in size from nervous and second lymphoid tissues and sera and, to reflect its unknown identity, named "Virus X". The presence of virus particle with morphological characteristics similar to Virus X in tissues from affected animals was also observed on thin-section positive-staining electron microscopy. Isolates of Virus X were not readily recognized by antibodies raised against any known viruses pathogenic to swine but by antisera collected from animals surviving clinical episode, indicating that Virus X is likely a previously unrecognized agent. Pregnant sows experimentally inoculated with Virus X (ISUYP604671) or homogenate (filtrate) of tissues from a clinically affected animal developed clinical signs and pathological changes similar to field observations including the loss of pregnancy. Furthermore, caesarian-derived, colostrum-deprived young pigs developed mild encephalomyelitis lesions in brains after experimental inoculation with the virus or the tissue homogenate although clinical neurologic signs were not observed. More importantly, Virus X was re-isolated from all inoculated animals while control pigs remained negative for the virus during the study. Collectively, Virus X is a novel viral agent responsible for PRNS and remains to be further characterized for taxonomical identity. 相似文献
42.
A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic conditions. Yet, the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly investigated. Focusing on terrestrial mammals in China, one of the world's megadiverse countries, we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes, namely, national nature reserves (NNRs), priority areas for biodiversity conservation (PABCs), and key biodiversity areas (KBAs). Among the 440 species assessed with moderate or high exposure to floods, 327 (∼75%) also qualified as moderate or high in exposure to intense human pressure. These species mainly belong to the orders Chiroptera, Eulipotyphla, and Rodentia. Likewise, there were 305, 311, and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs, PABCs, and KBAs, respectively. Our findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China, considering threats to species from exposure to adverse effects from both extreme climate and human pressure. 相似文献
43.
Daub Matthias Hakl Ulrike Molendijk Leendert PG Schomaker Corrie Been Thomas H van Beers Thea G Jivishova Sevda Jivishov Emil Keusgen Michael Bluemel Roman Fischer Daniel Grundler Florian MW Reuther Marie Cappel Sabrina Bauer Harald Lang Christian Watrin Cliff den Nijs Loes JMF Van Bruggen Anne-Sophie Karssen Gerrit Kiewnick Sebastian Büchler Urs Roth Irma Frey Jürg 《植物病害和植物保护杂志》2015,122(4):189-193
Journal of Plant Diseases and Protection - 相似文献
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45.
Two new nematode species, Paragendria papuanensis sp. n. (Quimperiidae) and Rhabdochona papuanensis sp. n. (Rhabdochonidae), are described from the intestine of freshwater fishes Glossamia giellerupi (Weber et Beaufort) (Apogonidae) and Melanotaenia affinis (Weber) (Melanotaeniidae), respectively, from the Sogeram River (Ramu River basin), Madang Province, northern Papua New Guinea. The former species is characterized mainly by the absence of oesophageal teeth, the presence of conspicuously inflated papillae of the last two subventral pairs, a gubernaculum, spicules 69-75 microm long, eggs measuring 57-66 x 39-45 microm, and by a small body (male and female 3.2-3.7 and 5.8 mm long, respectively). Paragendria is considered a valid genus, to which P. aori (Khan et Yaseen, 1969) comb. n., P. guptai (Gupta et Masoodi, 2000) comb. n., P. hanumanthai (Gupta et Jaiswal, 1988) comb. n. and P. vermae (Gupta et Masoodi, 2000) comb. n. are newly transferred. Rhabdochona papuanensis differs from all congeners mainly in having hammer-shaped deirids and from individual species also in other characters. Both findings represent the first records of species of Paragendria and Rhabdochona from the Australian zoogeographical region and the first records of the representatives of these genera from fishes of the families Apogonidae and Melanotaeniidae, respectively. 相似文献
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47.
Timothy A Georoff Priscilla H Joyner John P Hoover Mark E Payton Roman M Pogranichniy 《Journal of zoo and wildlife medicine》2008,39(3):335-341
Laboratory records of serology results from captive macropodidae sampled between 1997 and 2005 were reviewed to assess the seroprevalence of retrovirus exposure. Serum samples from 269 individuals (136 males, 133 females) representing 10 species of macropods housed in 31 North American captive collections were analyzed for retrovirus antibody using an indirect immunofluorescent assay. The prevalence of positive antibody titers comparing male versus female, between species, between age groups, and among animals with identified parentage was examined by nonparametric statistical analyses. Median age of animals at time of sample collection was 36 mo (range 2-201 mo). Total percentage seropositive was 20.4%. Serum antibody was detected in 31 of 47 (66.0%) tammar wallaby (Macropus eugenii), nine of 24 (37.5%) yellow-footed rock wallaby (Petrogale xanthopus), four of 11 (36.4%) swamp wallaby (Wallabia bicolor), 10 of 80 (12.5%) red-necked wallaby (Macropus rufogriseus), and one of 54 (1.9%) parma wallaby (Macropus parma). No individuals of western gray kangaroo (n=3) (Macropus fuliginosus), eastern gray kangaroo (n=19) (Macropus giganteus), common wallaroo (n=6) (Macropus robustus), red kangaroo (n=11) (Macropus rufus), or Matschie's tree kangaroo (n=14) (Dendrolagus matschiei) were positive for retrovirus antibody. These results demonstrate that five species of captive macropods have a history of exposure to retrovirus, with the highest percentage seropositive and highest statistical correlation in M. eugenii (pair-wise Fisher's exact test, alpha = 0.05). Additionally, one wild-caught M. eugenii was confirmed seropositive during quarantine period, indicating that retrovirus exposure may exist in wild populations. 相似文献
48.
Daniel Mageste de Almeida Marcos Inácio Marcondes Luciana Navajas Rennó Lívia Vieira de Barros Carla Heloísa Avelino Cabral Leandro Soares Martins David Esteban Contreras Marquez Felipe Vélez Saldarriaga Faider Alberto Castaño Villadiego Manuela Acevedo Cardozo Roman Maza Ortega Javier Enrique Garces Cardenas Virginia Lucia Neves Brandão Mário Fonseca Paulino 《Tropical animal health and production》2018,50(8):1771-1777
Beef cows’ milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows. Eighty Nellore cows were used, with initial weight of 516.0?±?1.0 kg. The experiment was a completely randomized factorial scheme, with 20 replications and four treatments (i.e., +?or ??pre-partum supplementation in combination with +?or ??post-partum supplementation): PRMM—1 kg of supplement/cow/day for 90 days pre-partum; MMPS—1 kg of supplement/cow/day for 90 days post-partum; PRPS—1 kg of supplement/cow/day for 90 days pre-partum and 90 days post-partum; and MM—only mineral mix ad libitum during pre- and post-partum. Milk was sampled on days 45, 135, and 225 post-partum (early, middle, and late lactation, respectively). No effects were observed of pre- and post-partum supplementation on milk yield (P?>?0.05). The afternoon/morning proportion of 0.45 in the early third of lactation was higher than other stages, which had a proportion of 0.41 (P?<?0.05). Post-partum supplementation increased milk protein in the morning and afternoon milking (P?<?0.05). There was also no effect of pre- and post-partum supplementation on afternoon-morning proportion other milk components (P?>?0.05). We conclude that estimating daily milk production of grazing beef cattle by multiplying a once daily milking amount times two is not accurate. Under the conditions of this study, proportion of total daily production represented by the ratio of afternoon/morning milking was 0.45 in early lactation (first third) and 0.41 in mid- and late lactation. 相似文献
49.
Arnaldo Cintra Limede Rodrigo S Marques Daniel Montanher Polizel Bruno Ieda Cappellozza Alexandre Arantes Miszura Jos Paulo Roman Barroso Andr Storti Martins Lairana Aline Sardinha Marcelo Baggio Alexandre Vaz Pires 《Journal of animal science》2021,99(4)
The aim of the present study was to evaluate the inclusion of narasin, salinomycin, or flavomycin for 140 d on ruminal fermentation parameters, apparent nutrient digestibility, and performance of Nellore cattle offered a forage-based diet. In experiment 1, 32 rumen-cannulated Bos indicus Nellore steers [initial body weight (BW) = 220 ± 12.6 kg] were assigned to individual pens in a randomized complete block design according to their initial shrunk BW. Within block, animals were randomly assigned to 1 of 4 treatments: (1) forage-based diet without feed additives (CON; n = 8), (2) CON diet plus 13 ppm of narasin (NAR; n = 8), (3) CON diet plus 20 ppm of salinomycin (SAL; n = 8), or (4) CON diet plus 3 ppm of flavomycin (FLA; n = 8). The experimental period lasted 140 d and was divided into 5 periods of 28 d each. The inclusion of feed additives did not impact (P ≥ 0.17) dry matter intake (DMI), nutrient intake, and apparent total tract digestibility of nutrients. Nonetheless, steers fed NAR had lower (P < 0.01) molar proportion of acetate compared with CON, SAL, and FLA steers, whereas ruminal acetate tended to be greater (P < 0.09) for SAL vs. CON and FLA, but did not differ (P = 0.68) between CON vs. FLA steers. Ruminal propionate was the highest (P < 0.01) for steers fed NAR and did not differ (P > 0.20) between CON, SAL, and FLA. Consequently, NAR steers had the lowest (P < 0.01) Ac:Pr ratio, whereas Ac:Pr did not differ (P > 0.18) among CON, SAL, and FLA. Total volatile fatty acids were greater (P < 0.04) for NAR and CON vs. SAL and FLA, but did not differ (P > 0.67) among NAR vs. CON and SAL vs. FLA. In experiment 2, 164 Nellore bulls (initial shrunk BW = 299 ± 2.5 kg) were assigned to feedlot pens for 140 d in a randomized complete block design. Within block (n = 10), animals were randomly assigned to the same treatments used in experiment 1. Average daily gain was greater (P < 0.01) in NAR vs. CON, SAL, and FLA bulls, and did not differ (P > 0.12) between CON, SAL, and FLA bulls. Bulls fed NAR had greater (P < 0.02) DMI (as kg/d or % BW) and final shrunk BW compared with CON, SAL, and FLA bulls, whereas DMI and final shrunk BW did not differ (P > 0.26) between CON, SAL, and FLA bulls. Feed efficiency, however, was not impacted (P = 0.51) by any feed additives used herein. Collectively, narasin was the only feed additive that benefited performance and ruminal fermentation of Nellore animals fed a forage-based diet. 相似文献
50.
Stephanie Rutherford Frederic Gaschen Roman Husnik Jon Fletcher Lorrie Gaschen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2022,36(2):508
BackgroundErythromycin, a macrolide antibiotic with motilin agonist properties, shortens gastric emptying (GE) time in healthy cats. Azithromycin, another macrolide antibiotic, is effective for treatment of gastric paresis in people.ObjectivesTo evaluate the effects of azithromycin on GE and gastric motility in healthy cats in comparison with erythromycin (positive control) and placebo.AnimalsEight healthy purpose‐bred cats.MethodsProspective, blinded, crossover study. Cats received either azithromycin (3.5 mg/kg PO q24h), erythromycin (1 mg/kg PO q8h), or placebo for 24 hours before and during evaluation of GE. A validated method using ultrasound for sequential measurements of antral area as well as amplitude and frequency of contractions was used to assess GE and evaluate gastric antral motility postprandially over an 8‐hour period.ResultsGE was significantly faster (P < .05) after administration of azithromycin and erythromycin when compared to placebo in the late phase of fractional emptying from 75% (mean ± SD: 327 ± 51 minutes, 327 ± 22 minutes, and 367 ± 29 minutes, respectively), to 95% fractional emptying (399 ± 52 minutes, 404 ± 11 minutes, and 444 ± 24 minutes, respectively). The drugs had no significant effect on antral motility variables at any time point.Conclusions and Clinical ImportanceAzithromycin and erythromycin shorten GE time in a comparable manner in healthy cats. Evaluation of their efficacy in cats with gastric dysmotility is warranted. 相似文献