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1.
In the present study endoscopically diagnosed changes of the Fürstenberg's rosette were examined histologically. For this purpose the teats of 200 slaughtered cows were inspected. In 19 cases proliferations in the region of the Fürstenberg's rosette were found. Additionally, tissue samples were taken from the Fürstenberg's rosette of 26 cows which showed milk flow disorders due to stenoses of this part of the teat. Teats of slaughtered cows as well as biopsy specimens were fixed in 5% formaldehyde and embedded in paraffin and in plastic. All specimens were stained according to H.E., Giemsa and Turnbull, respectively. Histologically, the proliferations of the Fürstenberg's rosette consisted of fibrovascular tissue (granulation tissue) covered by keratinized squamous epithelium (teat canal epithelium) in eleven cases. In the other cases double-layered cuboid epithelium (cisternal epithelium) was found additionally. The formation of granulation tissue and deposition of blood pigment was observed exclusively in areas covered by stratified epithelium. Therefore a traumatic lesion of the teat canal was supposed to be the cause of the histological findings. In contrast to several reports in the literature, however, no indications of an inversion of the teat canal epithelium were found. On the basis of these findings, the hitherto assumed idea of pathogenesis of proliferations of the Fürstenberg's rosette was modified and a new pathogenesis pattern was developed.  相似文献   

2.
This article explores some themes in the agrarian and environmental history of the Karoo since 1800. It argues that environmental change cannot be understood without incorporating social, economic and political history. This is especially so in the case of the Karoo because the landscape and ecology was transformed by intensive commercial livestock production in the nineteenth and twentieth centuries. The scale and economic significance of sheep farming and wool production up to the 1960s is generally underestimated in histories of the Cape and South Africa. The article outlines the patterns of economic growth and also the technologies required, such as fencing and water provision. The environmental impact of intensive livestock farming was recognised from the late eighteenth century and new scientific approaches helped to define understandings of environmental change. Environmental degradation was at its height in the first half of the twentieth century; simultaneously, conservationist ideas were developed and gradually implemented. In the second half of the twentieth century, these approaches, together with socio-economic factors that led to lower levels of stocking, resulted in a stabilisation and even some environmental recovery.  相似文献   

3.
The objective of this study was to obtain information of epidemiological nature through genotypic characterization of Cryptosporidium isolates from dogs, cats and bovines from the state of São Paulo, Brazil. The extraction of DNA from oocysts was carried out and polymerase chain reaction was accomplished using specific primers to 18S rRNA gene. The amplicons were directed sequenced. Seven cat samples, nine dog samples and nine bovine samples were analysed. From the seven cat samples the genotypic analyses revealed Cryptosporidium felis in all. These were the first genotypic characterization of Cryptosporidium from domestic felines in Brazil. In nine sequenced samples from dogs, genotypic identities compatible with Cryptosporidium canis were revealed in all samples. The genotypic analyses in bovines revealed Cryptosporidium parvum in eight samples and Cryptosporidium bovis in another sample, the last one being a non-zoonotic species, not related to clinical symptoms and described for the first time in Brazil.  相似文献   

4.
<正>In the 1950s and early 1960s,the American society took on an air of unprecedented material prosperity.However,the flourishing economy failed to provide people with the spiritual content they expected to come with it.The inanition in the spiritual world and the affluence in the material world created a sharp contrast which led to a growing sense of anxiety and dissatisfaction.As a result,"many Americans reacted to these developments with ambivalence,even hostility."(Brinkley 1999:  相似文献   

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Canine monocytic ehrlichiosis caused by Ehrlichia canis is endemic in many regions of Brazil. Since thrombocytopenia is a common finding in infected dogs, many clinicians tend to use it as an indication for antibiotic treatment. Polymerase chain reaction (PCR) and nested PCR were used to study the presence of E. canis, Anaplasma platys and Babesia spp. in thrombocytopenic and non-thrombocytopenic dogs from Ribeirão Preto, Brazil. Despite the high prevalence of E. canis infection among thrombocytopenic dogs, 46.7% of the thrombocytopenic dogs studied were either infected with Babesia spp. or A. platys or not infected with any of the three pathogens. There was a high incidence (25.4%) of E. canis infection in non-thrombocytopenic dogs. Although infection with E. canis should be considered in thrombocytopenic dogs, the final diagnosis needs to be confirmed by complementary tests such as blood smears and PCR to avoid the unnecessary use of antibiotics.  相似文献   

7.
This review article explores past, present and possible future drivers of change in Karoo social-ecological systems. Biogeographically, the Karoo comprises the arid Succulent Karoo and Nama-Karoo biomes covering significant portions of the Northern Cape, Eastern Cape and Western Cape provinces and a smaller part of the Free State. Despite the Karoo’s specific environment and spatial importance nationally (covering some 30% of South Africa), no government structures address its needs holistically. Today it is a politically and economically marginalised region; perceptions of it as a desert easily morph into perceptions of it as deserted and ripe for exploitation for the benefit of external constituencies, whether in the name of astronomy, shale-gas and uranium mining or renewable energy. To manage the Karoo better for present and future generations, it is clearly desirable for social and natural scientists to work collaboratively, yet there is relatively little interdisciplinary work to date. Against this background this review article provides an overview of social and ecological changes historically and in the present, and offers some cautious reflections concerning climate change, changing land use and governance as key drivers affecting trajectories of change into the future.  相似文献   

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Leptospirosis is a zoonotic disease with worldwide distribution. The disease affects dairy and beef cattle, causing infertility, abortion, and reduced milk yield. A cross-sectional study was conducted to determine the seroprevalence of leptospirosis in cattle and the associated risk factors in the province of Manabí, Ecuador. Serum samples from 749 animals from 55 cattle herds were analyzed using the microscopic agglutination test (MAT). Animals were considered positive when titers were ≥ 1:100. The association between the potential risk factors and the positive Leptospira result was modeled at both animal and herd level using a generalized linear model with a binomial distribution and logarithmic link. The seroprevalence was 56.21% at the individual level and 98.18% at the herd level. The most prevalent serovars were Pomona (28.57%) and Icterohaemorragiae (22.30%). At the animal level, only the age was associated with leptospirosis seropositivity. Seroprevalence in animals over three years of age was 1.197 (95% confidence intervals (CI), 1.032 – 1.390), higher compared to animals up to three years old. The seroprevalence of Leptospira spp. was higher in farms with no veterinary assistance (PR = 1.209; 95%CI 1.053 – 1.388) and without a vaccination program against Leptospira (PR = 1.399; 95%CI 1.09 - 1.794). In addition, herds from Junín canton had a significantly higher seroprevalence of Leptospira spp (PR = 1.548; 95%CI 1.213 - 1.977) compared to the Bolívar canton, which had the lowest seroprevalence. In conclusion, more than half of the animals were positive to Leptospiraspp, and almost all herds had at least one positive animal. Furthermore, veterinary assistance and vaccination of cattle must be considered as essential aspects of the disease control program.  相似文献   

10.
1. The objective of the present study was to examine the effect of in ovo injection of disaccharides (DS), disaccharides and glutamine (DS + Gln) or disaccharides and β-hydroxy-β-methylbutyrate (DS + HMB) at d 23 of incubation on the development of the small intestine. 2. In DS + Gln-injected ducks, the greatest relative small intestine mass and muscularis layer thickness among 4 treatments was observed from d 25 of incubation to 7 d of age. 3. Jejunal sucrase activity in DS-injected ducks was significantly greater than in controls at hatch and on d 7. 4. In DS + HMB-treated ducks, a tendency toward slightly higher jejunal DNA concentration was observed throughout the experiment. 5. Greater body weight was found in DS + Gln and DS + HMB treated ducks in the first two weeks. However, there was no significant difference in the market weight (35 d) of ducks among the 4 treatments. 6. The results of present study suggest that administering disaccharides and Gln, or disaccharides and HMB, to the duck embryos exerted a beneficial effect on the early development of small intestine and on growth performance.  相似文献   

11.
Tropical Animal Health and Production - This study shows the absence of the world’s most common bacterial zoonoses caused by Brucella abortus and Brucella melitensis in cattle, goats and dogs...  相似文献   

12.
Swine influenza (SI) is a seasonal infectious disease highly important to the world pig industry. Loss of daily weight gain, increased costs for the prevention and treatment of secondary infections are the main economic losses associated with the presence of this disease. However, some epidemiological features of SI remain quite unclear. This study focused on assessing the prevalence of swine influenza virus (SIV) infection in intensive and extensive pig herds and associating risk factors. A set of 601 blood samples of five intensive farrow-to-finish farms and 361 blood samples from 56 extensive farms were analyzed using an indirect ELISA kit CIVTEST SUIS INFLUENZA®, Hipra (Amer, Spain), in order to detect anti-SIV antibodies. In total, 24.13 % of samples from intensive herds were positive, while no positive samples were detected in extensive rearing herds. Sow and weaning piglets had the highest prevalence values. In the intensive rearing system, occurrence of reproductive disorders and exposure to recently introduced animals were positively associated with the disease occurrence in swine herds. The findings highlight the importance of sows in the epidemiology of the disease and bring information about risk factors involved in the occurrence of swine influenza in intensive herds.  相似文献   

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Tropical Animal Health and Production - An exploratory survey was conducted to understand breeding practices and breeding objectives as well as the constraints as a first step towards developing...  相似文献   

16.
1. The role of certain fish meals in the production of localised gizzard erosion is confirmed.

2. Lesions typical of gizzard erosion could be produced by the addition of histamine to the diet.

3. The amount of histamine occurring naturally in fish meal depends on the species of fish and the extent and nature of bacterial spoilage.

4. These variables may explain why histamine has not been implicated previously and also why there have not been consistent associations between the condition and geographical source or common factors in bulk consignments of the meal.  相似文献   


17.
Glaucoma and inherited retinal degeneration/dystrophy are leading causes of blindness in veterinary patients. Currently, there is no treatment for the loss of vision that characterizes both groups of diseases. However, this reality may soon change as recent advances in understanding of the disease processes allow researchers to develop new therapies aimed at preventing blindness and restoring vision to blind patients. Elucidating the molecular mechanisms of retinal ganglion cell death in glaucoma patients has led to the development of neuroprotective drugs which protect retinal cells and their function from the disastrous effects of elevated pressure. Identification of the genetic mutation responsible for inherited degenerations and dystrophies of the outer retina has enabled researchers using gene therapy to restore vision to blind dogs. Other patients may benefit from retinal transplantation, stem cell therapy, neuroprotective drugs, nutritional supplementation and even retinal prostheses. It is possible that soon it will be possible to restore sight to some blind patients.  相似文献   

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Background

Previous studies have reported a seasonal increased risk for leptospirosis, but there is no consistent seasonality reported across regions in the United States.

Objectives

To evaluate and compare seasonal patterns in seropositivity for leptospirosis in dogs for 4 US regions (northeast [NE], midwest [MW], south‐central [SC], and California‐southern west coast [CS]).

Animals

Forty four thousand nine hundred and sixteen canine serum samples submitted to a commercial laboratory for microscopic agglutination tests (MAT) from 2000 through 2010.

Methods

In this retrospective study, positive cases were defined as MAT titers ≥1 : 3,200 for at least one of 7 tested serovars. Four geographic regions were defined, and MAT results were included in regional analyses based on hospital zipcode. A seasonal‐trend decomposition method for times series was utilized for the analysis. Monthly variation in the seropositive rate was evaluated using a seasonal cycle subseries plot and logistic regression.

Results

Two thousand and twelve of 44,916 (4.48%) samples were seropositive. Compared to seropositive rates for February, significantly higher monthly rates occurred during the 2nd half of the year in the MW (OR 3.92–6.35) and NE (OR 2.03–4.80) regions, and only in January (OR 2.34) and December (OR 1.74) in the SC region. Monthly seropositive rates indicative of seasonality were observed earlier in the calendar year for both CS and SC regions.

Conclusions and Clinical Importance

Seasonal patterns for seropositivity to leptospires differed by geographic region. Although risk of infection in dogs can occur year round, knowledge of seasonal trends can assist veterinarians in formulating differential diagnoses and evaluation of exposure risk.  相似文献   

20.
Intestinal parasites, both helminths and protozoa, are commonly found in domestic animals, and the possible transmission of enteric parasites from dogs and cats to humans may constitute a global potential health risk worldwide. In the present study, we analysed 148 stool samples from dogs (n=126) and cats (n=22) collected from animal shelters and veterinary clinics, in the district of évora, Portugal. Microscopic examination confirmed that Giardia was the most frequent parasite in the studied population (34/148; 23%). Other parasites such as Ancylostoma sp., Isospora spp., Toxocara, Trichuris spp., Toxascaris and Toxoplasma were also found. Furthermore, molecular characterization of Giardia duodenalis analysis targeting the small subunit ribosomal RNA (ssu-rRNA) was performed revealing the presence of host-specific (C and D) and zoonotic assemblages (A and B). This work points out to the importance of protozoan parasites in companion animals, and reanalyses the need for parasite prophylaxis.  相似文献   

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