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Occurrence of canine parvovirus type 2c in the United States.   总被引:3,自引:0,他引:3  
Canine parvovirus (CPV) type 2 (CPV-2) emerged around 1978 as a major pathogen of dogs worldwide. In the mid-1980s, the original CPV-2 had evolved and was completely replaced by 2 variants, CPV-2a and CPV-2b. In 2000, a new variant of CPV (named CPV-2c) was detected in Italy and now cocirculates with types 2a and 2b in that country. The CPV-2c has also been reported from single outbreaks in Vietnam and Spain. This study was conducted to determine if CPV-2c occurs in the United States. Thirty-three fecal samples were collected from dogs in 16 states between April 2006 and April 2007 and were tested for CPV using real-time polymerase chain reaction (PCR). Positive samples were further tested using conventional PCR and minor-groove binding TaqMan PCR assays to determine the viral type and to differentiate vaccine strains from field strains. Twenty-seven samples were positive for CPV, 7 of which were CPV-2c from 5 states: Arizona, California, Georgia, Oklahoma, and Texas. Of the 7 isolates, 4 differed from European CPV-2c isolates by 2 additional single-nucleotide mutations at positions 4076 and 4104, the latter of which produces a ThrAla change at residue 440 located near a major antigenic site. The coast-to-coast geographic distribution of the states in which CPV-2c was detected strongly suggests that this new CPV variant is probably widespread in the United States. The continuous evolution of CPV requires that monoclonal antibody-based and nucleic acid-based diagnostic assays should be periodically checked for sensitivity on prevalent CPV strains.  相似文献   

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A survey was conducted to ascertain the prevalence of Fanconi syndrome in Basenjis and to determine in which geographic regions the greatest number of affected dogs resided. A thousand questionnaires were distributed nationally, and 624 (62%) were returned. Through this survey, prevalence, geographic distribution, and breeder involvement were successfully correlated with the overall association of the disease with the Basenji breed. Ten percent (96/959) of all Basenjis involved in the survey had Fanconi syndrome. Half (50%; 48/96) of the Basenjis affected were between 4 and 8 years old. Seventy-six percent (44/58) of owners of Basenjis with Fanconi syndrome were breeding their dogs, and 93% (52/56) had owned other Basenjis before the survey was conducted. Females outnumbered males (3:1) in frequency of the disease. This ratio reflected the higher breeder participation in the survey, rather than being a true gender predilection for the disease.  相似文献   

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During 2000, 49 states, the District of Columbia, and Puerto Rico reported 7,364 cases of rabies in nonhuman animals and 5 cases in human beings to the Centers for Disease Control and Prevention, an increase of 4.3% from 7,067 cases in nonhuman animals reported in 1999. Ninety-three percent (6,855 cases) were in wild animals, whereas 6.9% (509 cases) were in domestic species (compared wth 91.5% in wild animals and 8.5% in domestic species in 1999). Compared with cases reported in 1999, the number of cases reported in 2000 increased among bats, dogs, foxes, skunks, and sheep/goats and decreased among cats, cattle, horses/mules, raccoons, and swine. The relative contributions of the major groups of animals were as follows: raccoons (37.7%; 2,778 cases), skunks (30.2%; 2,223), bats (16.8%; 1,240), foxes (6.2%; 453), cats (3.4%; 249), dogs (1.6%; 114), and cattle (1.1%; 83). Ten of the 19 states where the raccoon-associated variant of the rabies virus has been enzootic reported increases in the numbers of cases of rabies during 2000. Among those states that have engaged in extensive wildlife rabies control programs, no cases of rabies associated with the epizootic of rabies in raccoons (or in any other terrestrial species) were reported in Ohio, compared with 6 cases reported in 1999. No rabies cases associated with the dog/coyote variant (compared with 10 cases in 1999, including 5 in dogs) were reported in Texas, and cases associated with the gray fox variant of the virus decreased (58 cases in 2000, including 38 among foxes). Reports of rabid skunks exceeded those of rabid raccoons in Massachusetts and Rhode Island, states with enzootic raccoon rabies, for the fourth consecutive year. Nationally, the number of rabies cases in skunks increased by 7.1% from that reported in 1999. The greatest numerical increase in rabid skunks (550 cases in 2000, compared with 192 in 1999) was reported in Texas. The number of cases of rabies reported in bats (1,240) during 2000 increased 25.4% over the number reported during 1999 (989) and represented the greatest contribution (16.8% of the total number of rabid animals) ever recorded for this group of mammals. Cases of rabies reported in cattle (83) and cats (249) decreased by 38.5% and 10.4%, respectively, whereas cases in dogs (114) increased by 2.7% over those reported in 1999. Reported cases of rabies among horses and mules declined 20% from 65 cases in 1999 to 52 cases in 2000. Four indigenously acquired cases of rabies reported in human beings were caused by variants of the rabies virus associated with bats. One case of human rabies acquired outside the United States that resulted from a dog bite was caused by the canine variant of the rabies virus.  相似文献   

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In 1990, the United States and its territories reported 4,881 cases of rabies in animals to the Centers for Disease Control, a 1.5% increase from 1989. Of these, 553 were domestic animals, 4,327 were wild animals, and one was a human being. Pennsylvania reported the highest number (611) of rabies cases in animals in 1990. For the first time since surveillance of rabies in wild animals was begun in the 1950s, the number of cases of rabies in raccoons exceeded that in skunks. Particularly large increases of cases of rabies in wild and domestic animals were reported in New Jersey (469 cases in 1990 compared with 50 cases in 1989, an increase of 838% from 1989) and New York (242 cases in 1990 compared with 54 cases in 1989, an increase of 348%). The 1,821 cases of rabies in raccoons represented a 17.9% increase over those reported in 1989 and 24.5% over those in 1988. This increase was largely attributable to the larger number of rabid raccoons in New Jersey and New York. Other states that reported an increased number of rabies cases in animals in 1990 included Utah (77.8%), Louisiana (64.7%), North Dakota (60.3%), Arizona (28.6%), Oklahoma (27.5%), Delaware (22.2%), and Maryland (20.6%). Thirty states reported a decrease in the number of cases of rabies in animals.  相似文献   

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In 1991, 49 states, the District of Columbia, and Puerto Rico reported 6,972 cases of rabies in nonhuman animals and 3 cases in human beings to the Centers for Disease Control. Ninety-one percent (6,354 cases) were wild animals, whereas 8.9% (618 cases) were domestic species. The total number of reported cases of rabies increased 42.9% over that of 1990 (4,881 cases), with most of the increase resulting from continued spread of the epizootic of rabies in raccoons in the mid-Atlantic and northeastern states. Large increases in cases of rabies in animals were reported from Connecticut (200 cases in 1991, compared with 3 in 1990, an increase of 6,567%), Delaware (197 cases in 1991, compared with 44 in 1990, an increase of 348%), New York (1,303 cases in 1991, compared with 242 in 1990, an increase of 326%), and New Jersey (994 cases in 1991, compared with 469 in 1990, an increase of 112%). Other noteworthy increases were reported by Wyoming (96.4%), Texas (69.7%), California (41.3%), Oklahoma (33.1%), Minnesota (31.4%), Georgia (26.7%), and Maryland (23.7%). Hawaii reported 1 imported case of rabies in a bat. Only 16 states reported decreases in rabies in animals in 1991, compared with 30 in 1990. Pennsylvania and Iowa reported decreases of 40.6% and 27.4%, respectively. Rhode Island was the only state that did not report a case of rabies in 1991.  相似文献   

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Mycotoxins are considered unavoidable contaminants in foods and feeds because agronomic technology has not yet advanced to the stage at which preharvest infection of susceptible crops by fungi can be eliminated. The aflatoxins have received greater attention than any of the other mycotoxins because of their demonstrated carcinogenic effects in susceptible animals and their acute toxic effects in humans. Since 1965, the U.S. Food and Drug Administration (FDA) has enforced regulatory limits on the concentrations of these toxins in foods and feeds involved in interstate commerce. The FDA routinely monitors the food and feed industries through compliance programs to ensure that the levels of exposure to these toxins are kept as low as practical. This report summarizes data generated from compliance programs on aflatoxins for the fiscal years 1989, 1990, and the first half of 1991. Commodities sampled included peanuts and peanut products, tree nuts, corn and corn products, cottonseed, and milk. Higher than usual levels of contamination were found in corn examined from all areas of the United States in 1989 as a result of the severe drought that affected the 1988 corn crop. The drought in parts of the South and Southeast in 1990 resulted in increased contamination in corn and peanuts from those areas. A review of the surveillance data obtained on deoxynivalenol, zearalenone, ochratoxin A, sterigmatocystin, penicillic acid, and patulin over the years along with available toxicological data for these mycotoxins indicated that no regulatory actions were warranted. The lack of sufficient surveillance data on other mycotoxins that occur in the United States can be attributed in part to the unavailability of reliable analytical methodology.  相似文献   

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The basic question asked in the beginning of this article was whether the evidence from research is persuasive enough to conclude that competition in the meatpacking industry is deficient. The literature review led to the conclusion that the answer is no. Research varies widely in terms of data and methodologic approaches. The research, however, clearly finds evidence of market power. Many SCP studies indicated the existence and exercise of market power, but the failure of the paradigm makes definitive conclusions dangerous. The NEIO studies showed a persistent gap between the price of livestock and marginal costs but the studies did not incorporate sufficient detail to prove specific behavior. Azzam and Anderson [4] conducted an extensive review of competition in meatpacking. In their summary, they offered criticisms of the SCP approach and the conduct parameter approach. These investigators concluded that the body of empiric evidence was insufficient to persuasively argue that the meatpacking industry was not competitive. Sexton [69] discussed more recent critiques of the conduct parameter appraoch. Despite its weaknesses, he concluded that market power estimates in meatpacking are modest but that structural changes on balance are beneficial, from an efficiency viewpoint. Examining the evidence either by data aggregation, methodology, or time period results in little difference in the qualitative interpretation. The research community has done what Nicholls [2] said was needed. The need remains relevant. The research leaves us with a clear picture and nagging questions. Azzam and Anderson [4] recommended that further research focus on the process of competition or the rivalrous interaction between competitors, and on competitors' strategies for responding to technologic and market forces, as the business history of the industry suggests. Specifically, they recommended two approaches. First, to develop empiric pricing models for short-term monitoring. Such models infer conduct from spatial price linkages rather than from concentration as do SCP studies or estimation of conduct parameters as do NEIO studies. Second, to study the dynamics of the competitive process, making use of data describing changes at the firm and plant level, to better understand the effect of market and technologic forces on the evolution of firm behavior and industry structure. After discussing existing research quality and future research needs, two practical things remain to do. The first centers on the following question: How important are the relatively small measures of market power? Most believable price distortions are found to be 3% or less. These distortions are below the 5% regulatory standards related to mergers used by the US Department of Justice and US Federal Trade Commission [70]. These standards, however, are guidelines and not law. Antitrust laws state that the exercise of market power is illegal. Courts and regulatory agencies also have not defined how much market power is significant and for how long a firm or firms must maintain significant market power [71]. From the viewpoint of public welfare, small impacts on price make a substantial difference to livestock producers and rival meatpacking firms. In relatively low-profit commodity businesses, small degrees of market power have significant profit implications. Small price or percentage impacts represent large total dollar amounts, especially over long time periods. To some, the evidence of market power provides clear reasons for antitrust lawsuits, conclusive evidence of weak and disinterested antitrust enforcement, and undeniable grounds for corrective legislation. If we conclude that action is needed, then the second issue emerges: What should be done and will our actions result in a net improvement? The research reviewed in the article by MacDonald elsewhere in this issue clearly shows the economic benefits of large meat processing firms. Likewise, some of the research reviewed here shows that increased concentration benefits producers and consumers. Some of the benefits of lower costs are passed on to producers through improved prices. The clear problems seen in the 1910s and 1920s--the pools and trusts--are not present in the 1990s and 2000s. Legislative action requiring the restructuring of the meatpacking industry or limiting behavior (similar to the Packer Consent Decree of 1920) will come at a large cost to the industry and society. So what should be done? Some people want to do nothing and allow the market to function unencumbered by political action. This approach ignores the problems seen in research. Some people want to go back in time, forgetting the economic incentives for change. They would legislate change in the market structure where they perceive problems, break up large meatpacking firms, restrict supposed problematic conduct, and eliminate contracting and vertical integration. Some people want to treat agriculture as a unique sector of society and create laws and regulations applicable to agriculture alone, regardless of whether the issues driving these actions apply to other sectors of the economy. Little, if any, thought is given to public and private costs or public and private benefits. Structural changes are clear. Research findings on the impacts and consequences are robust. What should be done, however, is not clear or robust. We are in the realm of second-best choices. The fact that we are in a realm of second-best choices is not satisfying to me nor will it likely be to agricultural producers and policy makers. What to do from here is not an economic decision (i.e., economics cannot provide a clear best answer). Rather, it is a political and public choice question that has economic implications: What do we want our livestock and meat industry to look like?  相似文献   

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直到19世纪末,像大多数液体一样,牛奶是依据体积来简单定价的。但是,每一位牛奶生产者都知道牛奶离统一标准还差很远。因为饲养管理、奶牛个体、泌乳期、季节和其他未知因素导致了牛奶成分的不同,例如,一些牛奶含有比其他牛奶多两倍的脂肪。1890年Babcock检测发展起来,这是一种简单、快速、准确地检测乳脂肪成分的方法。它可以直接确定从牛奶中提炼出奶油或者黄油的量,并且可以精确地预测奶酪的量。Babcock检测方法改革了牛奶的定价,并很快被购买牛奶的工厂采用。随着商业性乳产业的发展,牛奶量的检测从体积基准转向重量,因为精确地确定重…  相似文献   

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OBJECTIVE: To determine the prevalence of Streptococcus iniae in tilapia (Oreochromis spp), hybrid striped bass (Morone chrysops X M saxatilis), and channel catfish (Ictalurus punctatus) on commercial fish farms in the United States. ANIMALS: 1,543 fish (970 tilapia, 415 hybrid striped bass, and 158 channel catfish). PROCEDURES: The dry-swab technique was used for collection of specimens for streptococcal isolation. Specimens were shipped by overnight delivery and processed by use of standard bacteriologic techniques. RESULTS: Streptococcus iniae was not isolated from market-size channel catfish. Prevalence in tilapia and hybrid striped bass was 37 of 970 (3.81%) and 30 of 415 (7.23%), respectively. Prevalence by farm ranged from 0.0 to 27.4% for tilapia and 0.0 to 21.6% for hybrid striped bass. In tilapia, prevalence was lowest in market-size and nursery fish (4 of 239 [1.67%] and 3 of 339 [0.88%], respectively), with an increase in prevalence for fish in the grow-out stage (30 of 337 [7.96%]). For hybrid striped bass, prevalence was lowest in nursery and market-size fish (3 of 96 [3.12%] and 1 of 47 [2.12%], respectively) and highest in fish in the grow-out stage (26 of 272 [9.56%]). Prevalence in market-size tilapia and hybrid striped bass was 5 of 286 (1.75%). CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study do not support the contention that S iniae is a serious public health threat associated with commercially raised fish; rather, it represents a limited risk for older or immunocompromised people who incur puncture wounds while handling and preparing fish.  相似文献   

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Serologic testing for leptospiral antibody was conducted with the macroscopic agglutination test on 1,346 equine serum samples. These were collected from clinically normal horses in 123 purebred herds in the Northeast. Sixty-eight samples (5%) from the population tested reacted at significant levels (1:40 or higher) to one or more of the 5 serotype antigens used. These reactors were from 38 (31%) of the herds tested. Reactions to serotype pomona predominated in 25 (72%) of these 38 herds. Smaller numbers of herds had reactors to canicola, icterohemorrhagiae and grippotyphosa. No significant reactions to serotype hardjo were detected.  相似文献   

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