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81.
To obtain information about the porcine circovirus type 2 (PCV2) infection status of pigs in Cuba and the probable association of PCV2 with other porcine viruses, tissue samples collected from ill pigs were evaluated using polymerase chain reaction (PCR). The PCR analysis showed that 67.7% of the samples (23/34) from seven swine herds of six different geographic regions were detected to be positive for PCV2. Ten of the 23 PCV2 positive samples (43.5%) shown a concurrent infection with porcine parvovirus (PPV) and 17 of 23 PCV2 positive samples (73.9%) exhibited a concomitant infection with classical swine fever virus (CSFV). This study is the first report of PCV2 infecting pigs with different clinical conditions in Cuban swine herds and provides evidence of PCV2 co-infection with PPV and CSFV in the field.  相似文献   
82.
An antigen capture or sandwich ELISA (sELISA) was evaluated for the diagnosis of Hypoderma lineatum in cattle under field conditions in northwestern Spain. The kinetics of circulating hypodermin C (HyC) and specific antibodies during the course of natural infestation were determined in a group of 10 Frisian calves. In addition, oesophagi and blood samples were taken from 105 cows at a slaughterhouse in order to compare three methods for the diagnosis of H. lineatum: sandwich ELISA for the detection of the antigen HyC (sELISA), indirect ELISA for the detection of antibodies anti-HyC (iELISA) and the detection of first instars (L1) in the oesophagus. In naturally infested cattle, HyC was present in circulation at low levels during the early and late phases of the infestation. However, in the middle phase, coinciding with the presence of L1 in the oesophagus, two peaks of increased HyC concentration were observed. Specific antibodies increased progressively until the first appearance of larvae in warbles on the back. There was no correlation between antigen or antibody levels and the number of grubs in the back. Prevalence of first instars in the oesophagi of slaughtered cows was 21.9% (23/105). The percentage of cattle that were positive for circulating antigen was slightly higher (24.8%), suggesting the recent destruction of migrating larvae in some animals. However, there was no correlation between the number of L1 and HyC levels. With the iELISA, 79% of the animals were positive to Hypoderma, which means that a high percentage of those animals have been exposed to the parasite but they had no apparent current infestation. The sELISA is a good tool to follow larval development within the host; however, the episodic elevation of HyC levels limits the usefulness of this test for the early diagnosis of Hypoderma under field conditions.  相似文献   
83.
The aims of this study were to evaluate the immunomodulatory role of TGF-β1, IL-10, and INF-γ in spleen and liver extracts and supernatant cultures of white spleen cells from male symptomatic and asymptomatic dogs, naturally infected by Leishmania (Leishmania) chagasi. Thirty dogs from Araçatuba, São Paulo, Brazil, an endemic leishmaniosis area, were selected by positive ELISA serological reaction for Leishmania sp. and divided into two groups: asymptomatic (n = 15) and symptomatic (n = 15) consisting of animals with at least three characteristic signs (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotion problems, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy). After euthanasia, spleen and liver fragments were collected for ex vivo quantification of TGF-β1, IL-10, and INF-γ. Naturally active in vitro produced TGF-β1 was also evaluated in spleen cell culture supernatant. Spleen and liver extract of asymptomatic dogs had higher mean TGF-β1 levels than symptomatic dogs. High concentrations of IL-10 were found in spleen, and mainly in liver extract of both groups. Higher INF-γ concentrations were found in spleen extracts of symptomatic dogs, and in liver extracts of asymptomatic dogs. Extract of this cytokine was lower in spleen extract. Although INF-γ is being produced in canine infection, mean levels of TGF-β1 and IL-10 from spleen and liver extracts were quantitatively much higher; suggesting that immune response in both asymptomatic and symptomatic dogs was predominantly type Th2.  相似文献   
84.
Ceruloplasmin (Cp) determination could provide an objective measure of the health status of an animal and could be used as marker of animal health and welfare (Skinner, 2001) (Skinner, J. G., 2001. Special report. International standardization of acute phase proteins. Veterinary Clinical Pathology 30, 2-7.) but only manual methods have been reported to determine Cp concentrations in pigs (McCosker, 1961; Toussaint et al., 1995; Eckersall et al., 1996) (McCosker, P. J., 1961. Paraphenylenediamine oxidase activity and copper-levels in mammalian plasmas. Nature. 190, 887-889; Toussaint, M. J. M., Van Ederen, A. M., Gruys, E., 1995. Implication of clinical pathology in assessment of animal health and in animal production and meat inspection. Comparative Haematology International 5, 149-157; Eckersall, P. D., Saini, P. K., McComb, C., 1996. The acute phase response of acid soluble glycoprotein, alpha(1)-acid glycoprotein, ceruloplasmin, haptoglobin and C-reactive protein, in the pig. Veterinary Immunology and Immunopathology 51, 377-385). In the present study two automated methods based on the use of two different substrates for the determination of serum ceruloplasmin in pigs were developed, evaluated and compared. Both methods showed a good precision and detection limits, with no signs of inaccuracy and could be applied to biochemical autoanalyzers usually found in clinical laboratories using only minimal amounts of serum. Additionally the behaviour of Cp in experimental and clinical situations was studied showing an increase of around two fold after turpentine administration and significantly higher values in cases of pigs with inflammatory conditions when compared with healthy pigs.  相似文献   
85.
Ectoparasites are the major causes of skin lesions in animals. Clinical, skin scraping examination, and histopathological studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. Mange mites, lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. Skin biopsies were collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. Of 1,000 sheep and 600 goats examined, 815 (81.50%) sheep and 327 (54.5%) goats were infested with one or more types of ectoparasites. Sarcoptes scabiei var ovis, Demodex ovis, Psoroptes ovis, Bovicola ovis, Melophagus ovinus, and Amblyomma variegatum and other tick species were identified from sheep. S. scabiei var caprae, Demodex caprae, Linognathus stenopsis, and A. variegatum and other tick species were identified from goats. Gross skin lesions or defects observed on the skin include stained and ragged wool, loss of wool/hair, nodules, crusts, lichenification, and fissuring. Microscopic evaluation of H and E stained skin sections revealed lesions in the epidermal layer such as hyperkeratosis, acanthosis, and melanin inconsistency on the basal cells of the epidermis. Follicular keratosis, perifolliculitis, frunculosis, perivasculitis, and aggregates of inflammatory cells (of acute and chronic type) with fibrosis were experiential in the dermal layer of the skin. Most of the skin lesions caused by ectoparasites are overlapping. Thus, ectoparasites control program should be executed to reduce skin lesions as skins are the major export commodity of the country.  相似文献   
86.
Biological response modifiers (BRM) are compounds that interact with the immune system to regulate specific aspects of host response. The objective of this study was to describe clinical and morphological changes during involution of bovine mammary gland following a single-dose infusion of a BRM containing lipopolysaccharide and cellular fractions of Escherichia coli incorporated into liposomes. A massive leukocyte response and increased subepithelial stroma infiltration of mononuclear cells, eosinophils and mast cells was observed in BRM-treated quarters compared with untreated controls; however, morphologic parameters assessed at 11 days post infusion were indicative of only slightly accelerated involution compared with untreated controls. In addition, BRM infusion at the end of lactation did not interfere with mammary epithelial cell proliferation and caused only mild systemic effects.  相似文献   
87.
Delayed acute capture myopathy is the term used to describe the clinical syndrome observed in three roe deer captured by drive-nets and transported to an enclosure for scientific purposes. The animals died 48 h, 60 h and 8 days after being captured. The simultaneous deaths coincided with a previous episode of deliberate human disturbance. The histopathological findings were indicative of acute myopathy and myoglobinaemic nephrosis. These could be related to an ataxic myoglobinuric syndrome brought on by capture and transport operations. The lack of clinical signs and negative prognosis indicators in the period between capture and just before death. the absence of gross muscular lesions in the animal that died after 8 days post-capture, the simultaneous deaths of animals captured at different times and the evidence of deliberate human disturbance in the enclosure are suggestive of death triggered by a second stress episode.  相似文献   
88.
89.
Understanding the utilisation patterns of milk assists in designing appropriate dairy development schemes in rural communities. The objective of the study was to determine milk utilisation patterns in different smallholder farming systems in the Eastern Cape Province of South Africa. Data were collected through the administration of recording sheets to 130 randomly selected households in Alice, Fort Beaufort and Queenstown districts. Amounts of milk produced per household ranged from 9 to 21 l per household per day. Milk consumption/household/day was similar among the three districts. Milk consumption in the early lactation doubled the amount consumed in late lactation (P < 0.05). Milk in the communal areas was largely utilised as fresh or sour milk. Fresh milk was mostly used in tea/coffee or to make porridge for children. Sour milk was consumed with thick boiled maize meal. Fort Beaufort (10.2 ± 1.37 l/day) had the highest sour milk sales whilst Queenstown had the highest fresh milk sales (9.7 ± 5.57 l/day). It was concluded that quantities of milk consumed or sold as fresh or sour were generally low and varied across smallholder farming systems.  相似文献   
90.
Nematode infections are a serious constraint to pig production, especially where free range pig keeping is practiced. This study investigated the epidemiology of nematodes in free range pigs in Busia District, Kenya. Three hundred and six pigs from 135 farms were sampled for faeces that were analysed for nematode eggs per gram (EPG) of faeces using the McMaster technique. The nematode eggs were also identified to genus and species based on morphology. A questionnaire on risk factors was also administered to the pig owners. The overall prevalence and mean nematode EPG were 84.2% and 2,355, respectively. The nematode eggs were identified as those belonging to Oesophagostomum spp. (75%), Strongyloides ransomi (37%), Ascaris suum (18%), Metastrongylus spp. (11%), Trichuris suis (7%) and Physocephalus sexalatus (3%). The prevalence of nematodes was positively correlated (p < 0.05) with the amount of rainfall in the division of the pigs' origin (all nematodes except S. ransomi). The prevalence of nematodes was also associated with the age of the pigs. A lower burden of nematodes was associated (p < 0.05) with a history of deworming (A. suum) and the provision of night housing (S. ransomi and Metastrongylus spp.). In conclusion, this study has provided information on nematode infections and the associated risk factors for free range pigs in Busia District, which can be used when implementing integrated control measures.  相似文献   
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