985 resultados para diseases of cattle
Resumo:
The objective of this review on the investigation of "cara inchada" in cattle (CI), pursued over the last 30 years, was to elucidate the pathogenicity of the disease and come to proper conclusions on its etiology. CI has been widely considered to be of nutritional origin, caused primarily by mineral deficiency or imbalance. However, the disease consists of a rapidly progressive periodontitis, affecting the periodontal tissues at the level of the premolars and molars during the period of tooth eruption generally starting in young calves. The disease led to great economic losses for farmers in central-western Brazil, after the occupation of new land for cattle raising in the 1960s and 1970s. The lateral enlargement of the maxillary bones of affected calves gave the disease the popular name of "cara inchada", i.e., swollen or enlarged face. The enlargement was found to be due to a chronic ossifying periostitis resulting from the purulent alveolitis of CI. Black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with Actinomyces (Corynebacterium) pyogenes, were isolated in large numbers from the periodontal lesions. B. melaninogenicus could be isolated in small numbers also from the marginal gingiva of a few healthy calves maintained on CI-free farms. "In vitro"-assays showed that streptomycin and actinomycin, as well as the supernatants of cultivates of actinomycetes from soils of CI-prone farms, applied in subinhibitory concentrations to the bacteria tested, enhanced significantly (up to 10 times) the adherence of the black-pigmented B.melaninogenicus to epithelial cells of the bovine gingiva. The antibiotics are apparently produced in large quantities by the increased number of soil actinomycetes, including the genus Streptomyces, that develop when soil microflora are modified by cultivating virgin forest or "Cerrado" (tree-savanna) for the first time for cattle grazing. The epidemiology of CI now provides strong evidence that the ingestion with the forage of such antibiotics could possibly be an important determinant factor for the onset and development of this infectious periodontitis. The antibiotic enhanced adherence of B.melaninogenicus to the sulcus-epithelium of the marginal gingiva, is thought to allow it to colonize, form a plaque and become pathogenic. There is experimental evidence that this determinant factor for the development of the periodontitis is present also in the milk of the mothers of CI-diseased calves. It has been shown that the bacteria isolated from the periodontal CI-lesions produce enzymes and endotoxins capable of destroying the periodontal tissues. The epidemiology of CI, with its decline in incidence and its disappearance after several years, could be explained by the fact that the former equilibrium of the microflora of the once undisturbed virgin soil has been reached again and that the number of antibiotic producing actinomycetes has been anew reduced. By this reasoning and all the data available, CI should be considered as a multifactorial infectious disease, caused primarily by the anaerobic black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with the micro-anaerobic Actinomyces pyogenes. Accordingly, the onset and development of the infectious periodontitis is apparently determined by ingestion with the forage of subinhibitory concentrations of antibiotics produced in recently cultivated virgin soils. This hypothesis is supported by the recent observation of renewed outbreaks of CI-periodontitis in former CI-prone areas, following fresh cultivation after many years. The infectious nature of CI is confirmed by trials in which virginiamycin was used efficiently for the oral treatment of CI-diseased cattle. Previously it has been shown, that spiramycin and virginiamycin, used as additives in mineral supplements, prevented CI-periodontitis.
Resumo:
Argentina's central region includes an important area covered by shallow pampean lakes and dams. In these environments, fishing of pejerrey Odontesthes bonariensis Valenciennes, 1835 (Pisces, Atherinopsidae), the most important fresh-water fish of the country, is a relevant social activity and also a considerable economic resource. The main diseases found in this species were studied from 1992 to 2003 in the provinces of Córdoba, La Rioja and Santa Fe (30º and 35º S, 61º and 67º W). Most cases were registered in high temperature months. Lernaea sp and Aeromonas hydrophila were the etiological agents most frequently found. The trophic characteristics of the aquatic environments enhanced disease processes and caused massive death of O. bonariensis, due to complex hydrochemical interactions.
Resumo:
Sixteen outbreaks of Senna occidentalis (coffee senna) that occurred in cattle in the state of Rio Grande do Sul, Brazil, were reviewed. The great majority (75%) of the outbreaks occurred in adult cattle at pasture during the autumn and winter months with 50% in May, evidencing a striking seasonality. Mortality rates varied from 4.2% to 55.2% and cattle died 2 days up to 2 weeks after showing clinical signs that included dry feces (occasionally diarrhea), muscle weakness, reluctance to move, tachypnea, instability of the hind limbs with dragging of the toes, tremors in muscles of the thighs, neck, and head, ear dropping, sternal recumbency, lateral recumbency and death. Myoglobinuria characterized by a dark red or black discolored urine was a consistent finding in cattle affected at pasture but not in those poisoned by ration contaminated with coffee senna beans. Creatine phosphokinase serum activity was marked ly elevated. Main gross changes observed in 23 necropsies involved skeletal muscles of the hind limbs. These changes consisted of varying degrees of paleness of muscle groups. Subepicardial and subendocardial hemorrhages were present in the hearts of all affected cattle. Histologically a segmental degenerative myopathy of striated muscles was present in every case and had a multifocal polyphasic or monophasic character. Myocardial (3/23), hepatic (3/13), renal (3/10), and splenic (1/6) microscopic lesions were observed occasionally. Myocardial lesions were mild and consisted of vacuolation of cardiomyocytes or focal fibrosis. Hepatic changes consisted of diffuse hepatocelular vacuolation, cytosegrosomes within hepatocytes, and individual hepatocellular necrosis. Kidneys had vacuolar degeneration of tubular epithelium associated with acidophilic casts (proteinosis) within tubular lumina. In the spleen there was marked necrosis of lymphocytes of the white pulp. No histological changes were found in the brains of 13 affected cattle. The data of this study suggest that coffee senna poisoning is an important cause of death in cattle in southern Brazil.
Resumo:
This paper reports the occurrence and epidemiology of outbreaks of foot rot and other foot diseases in goats and sheep in the semiarid region of Paraíba, northeastern Brazil. Four farms were inspected for the presence of foot lesion in sheep and goats and for environmental conditions, general hygiene, pastures, and disease control measures. The prevalence of foot lesions was 19.41% (170/876) in sheep and 17.99% (52/289) in goats, ranging between 5.77% and 33.85% in different farms. Foot rot was the most common disease, affecting 12.1% of the animals examined (141/1165), but with significantly higher (p<0.05) prevalence in sheep (13.69%) than in goats (7.27%). The frequency of malignant foot rot was also significantly lower (p<0.05) in goats (9.53%) than in the sheep (40.83%). On one farm, Dorper sheep showed significantly higher (p<0.05) prevalence of foot rot (17.5%) than Santa Inês sheep (6.79%), and the number of digits affected was also higher in the former. Dichelobacter nodosus and Fusobacterium necrophorum were isolated from cases of foot rot. White line disease was found in 3.95% of the animals, sole ulcers in 1.29%, foot abscess in 1.03% and hoof overgrowth in 0.5%. The high rainfall at the time of occurrence, grazing in wetlands, clay soils with poor drainage, presence of numerous stony grounds, closure of the flocks in pens at night, and introduction of affected animals were considered predisposing factors for the occurrence of foot diseases.
Resumo:
Bovine meningoencephalitis caused by BHV-5, a double-stranded DNA enveloped virus that belongs to the family Herpesviridae and subfamily Alphaherpesvirinae, is an important differential diagnosis of central nervous diseases. The aim of this study was to describe the histological changes in the central nervous system of calves experimentally infected with BHV-5 and compare these changes with the PCR and IHC results. Formalin-fixed paraffin-embedded central nervous system samples from calves previously inoculated with BHV-5 were microscopically evaluated and tested using IHC and PCR. All the animals presented with nonsuppurative meningoencephalitis. From 18 evaluated areas of each calf, 32.41% and 35.19% were positive by IHC and PCR, respectively. The telencephalon presented more accentuated lesions and positive areas in the PCR than other encephalic areas and was the best sampling area for diagnostic purposes. Positive areas in the IHC and PCR were more injured than IHC and PCR negative areas. The animal with neurological signs showed more PCR- and IHC-positive areas than the other animals.
Presence of Porphyromonas and Prevotella species in the oral microflora of cattle with periodontitis
Resumo:
Abstratc: Bovine periodontitis is a progressive purulent infectious process associated with the presence of strictly and facultative anaerobic subgingival biofilm and epidemiologically related to soil management in large geographic areas of Brazil. This study aimed to detect species of the genera Porphyromonas and Prevotella, which occurr in periodontal pockets of cattle with lesions deeper than 5mm (n=26) and in gingival sulcus of animals considered periodontally healthy (n=25). Presence of the microorganisms was evaluated by independent-culture medium diagnostic method, using polymerase chain reaction (PCR) with specific primers of Porphyromonas asaccharolytica, P. endodontalis, P. gingivalis, P. gulae, Prevotella buccae, P. intermedia, P. loescheii, P. melaninogenica, P. nigrescens, P. oralis and P. tannerae. The species P. endodontalis (80.7%), P. melaninogenica (73.1%) and P. intermedia (61.5%) were the most predominant in samples of cattle with periodontitis. Regarding non-injured gingival sulcus of cattle, P. endodontalis (40%) and P. loeschei (40%) prevailed. Porphyromonas gingivalis, P. gulae and Prevotella tannerae were not detected in the 51 samples studied. Data evaluation by T test, enabled to verify that ocorrence of Porphyromonas asaccharolytica (p=0.000003), P. endodontalis (p=0.0023), Prevotella buccae (p=0.0017), P. intermedia (p=0.0020), P. melaninogenica (p=0.00006) and P. oralis (p=0.0028) is correlated with bovine periodontitis.
Resumo:
In vitro tests were carried out on the pathogenicity of nine isolates of the predatory fungi of the genus Monacrosporium (5 M. sinense isolates, 3 M. appendiculatum and 1 M. thaumasium isolate) for a phytonematode (second stage juveniles from Meloidogyne incognita, race 3), a free-living nematode (Panagrellus spp), and two gastrointestinal parasitic nematodes of cattle (infective larvae of Cooperia punctata and Haemonchus placei). A suspension containing 2,000 nematodes from each species was added to Petri dishes containing fungi and grown on 2% water-agar medium at 25oC in the dark for up to 7 days. The dishes were examined every other day for 7 days and predation-free nematodes were counted. The results showed that the free-living nematodes, Panagrellus spp, were the most susceptible (P<0.05), followed by the phytonematode M. incognita, while the controls were ³98.5% viable. However, a variable susceptibility of the nematodes to different fungi was observed. This indicates that the use of predatory fungi for the environmental control of nematodes will be limited by the multiplicity of nematodes in the environment and their differential susceptibility to fungal isolates of the same genus.
Resumo:
The aim of the present study was to determine whether lipoarabinomannan (LAM), in combination with Freund’s incomplete adjuvant (FIA), was able to improve cell-mediated and antibody-mediated immune responses against ovalbumin (OVA) in cattle. Twenty-three calves were assigned to four treatment groups, which were subcutaneously immunized with either OVA plus FIA, OVA plus FIA and LAM from Mycobacterium avium subsp avium, FIA plus LAM, or FIA alone. Lymphoproliferation, IFN-γ production and cell subpopulations on peripheral blood mononuclear cells before and 15 days after treatment were evaluated. Delayed hypersensitivity was evaluated on day 57. Specific humoral immune response was measured by ELISA. Inoculation with LAM induced higher levels of lymphoproliferation and IFN-γ production in response to ConA and OVA (P < 0.05). Specific antibody titers were similar in both OVA-immunized groups. Interestingly, our results showed that the use of LAM in vaccine preparations improved specific cell immune response evaluated by lymphoproliferation and IFN-γ production by at least 50 and 25%, respectively, in cattle without interfering with tuberculosis and paratuberculosis diagnosis.
Resumo:
The article focuses on keeping cattle calm and removing distractions that would scare cattle back from the chute.
Resumo:
The article discusses the importance of design and the people who run handling systems.
Resumo:
The conclusion of the article states "it appears that previously learned choices may affect future choices in Y-mazes for cattle. Another area that needs to be researched is the effects of a mildly aversive treatment versus a severely aversive treatment on the tendency of a bovine to resist changing a learned choice".
Resumo:
UANL
Resumo:
There is no baseline data available at present on the nature of various diseases that occur in a orchid population, under cultivation, in any commercial orchid farm maintained by small scale entrepreneurs who invest considerable amount of money, effort and time. The available data on type of disease symptoms, causative agent, , nature of pathogens, as to bacteria or ftmgi or any other biological agents, and their source, appropriate and effective control measures could not be devised, for large scale implementation and effective management, although arbitrary methods are being practiced by very few farms. Further influence of seasonal variations and environmental factors on disease outbreak is also not scientifically documented and statistically verified as to their authenticity. In this context, the primary objective of the present study was to create a data bank on the following aspects 1. Occurrence of different disease symptoms in Dendrobium hybrid over a period of one year covering all seasons 2. Variations in the environmental parameters at the orchid farms 3. Variations in the characteristics of water used for irrigation in the selected orchid farm 4. Microbial population associated with the various disease symptoms 5. Isolation and identification of bacteria isolated from diseased plants 6. Statistical treatment of the quantitative data and evolving statistical model
Resumo:
In forestry, availability of healthy seeds is an important factor in raising planting stock. Initial seed health and storage conditions are the major factors governing the germinability of seeds. Like seeds of agricultural and horticultural crops, forest tree seeds are also liable to be affected by micro-organisms during storage, which affects the germination, and reduces the viability. Further introduction of seed-borne diseases into newly sown crops/areas on account of using unhealthy seeds is also not ruled out. Availability of healthy stock of seedlings is intrinsic for raising plantations and to meet this requirement elimination of nursery diseases by appropriate chemicals is of prime imortance. As exotic tree species may become susceptible to various native pathogens, it is generally considered better to select indigenous tree species for large scale plantations as they are well adapted to local environment. However, before taking up large scale afforestation progranme involving any indigenous tree species, it is essential to have knowledge about seed disorders and seedling diseases and their management. with a View to select appropriate tree species with fewer seed disorders and seedling disease problems for use in further plantation programme, four indigenous tree species such as Albizia odoratissima (L.f) Benth., Lagerstroemia microcazpa Wt., Pterocazpus marsupiwn Roxb. and Xylia xylocarpa (Roxb.) Taub. were evaluated to meet the above parameters
Resumo:
Bamboos are vulnerable to various diseases which affect them in nurseries, plantations as well as in natural stands. In India, rot and blight of emerging culms have already been identified as the limiting factor of the bamboo production in many bamboo growing areas, especially in the coastal belts of Orissa (Jamaluddin et a1., 1992). Similarly, foliage blight and rust have been recorded to pose threat to nursery as well as outplanted seedlings which are in the early establishnent phase (Bakshi et a1., 1972; Harsh et a1., 1989). With the increased emphasis and priority on raising multipurpose tree species, large—scale planting of bamboos has been initiated recently in the State. Limited experience in raising the bamboo seedlings together with the lack of information on bamboo diseases and their control measures often resulted in partial to complete failure of many nurseries. Also, poor handling of bareroot seedlings for outplanting affected seriously the planting programme. This was clearly reflected by the large-scale nortality of outplanted young seedlings reported from many plantations. So far, no systanatic attempt has been made to study the diseases affecting bamboos in nurseries, plantations and natural stands in the country. Hence, the present investigation was taken up to conduct a systematic study of the diseases affecting bamboos in Kerala.