998 resultados para Ruminal protozoa
Resumo:
In order to investigate epidemiological and clinical aspects of beef cattle mortalities caused by botulism, a syndrome popularly known as doença da vaca caída, studies were carried out in 32 naturally affected 4 to 9 year old cows, 27 belonging to the Nellore breed and 5 to crossbred Nellore, all from 27 farms located in municipalities near Botucatu, State of São Paulo. The epidemiological and clinical features were based, respectively, on the farm and herd managements, and on the general physical examination of the cows. Mouse bioassay and complement microfixation tests were performed to detect the presence of botulinum toxins in liver samples. The results showed that the disease occurs in beef cattle of range breeding systems, reared under inadequate mineral nutrition and deficient health management. Pregnant and milking cows represented the group at risk, and the incidence was higher during the rainy season (December to March), with morbidity and mortality rates of 3,2 ± 3,6%. Clinical examination revealed cows with no alterations of vital signs, behavior, visual and auditory acuities and skin sensation; but revealed ruminal hypomotility, anorexia, dehydration, flaccid para or tetraparesis with permanent recumbency, and a paretic or paralytic tongue. The diagnosis of botulism, involving type C and D toxins, was consistent with the epidemiological and clinical findings.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Despite vast efforts and expenditures in the past few decades, malaria continues to kill millions of persons every year, and new approaches for disease control are urgently needed. To complete its life cycle in the mosquito, Plasmodium, the causative agent of malaria, has to traverse the epithelia of the midgut and salivary glands. Although strong circumstantial evidence indicates that parasite interactions with the two organs are specific, hardly any information is available about the interacting molecules. By use of a phage display library, we identified a 12-aa peptide-salivary gland and midgut peptide 1 (SM1)-that binds to the distal lobes of the salivary gland and to the luminal side of the midgut epithelium, but not to the midgut surface facing the hemolymph or to ovaries. The coincidence of the tissues with which parasites and the SM1 peptide interact suggested that the parasite and peptide recognize the same surface ligand. In support of this hypothesis, the SM1 peptide strongly inhibited Plasmodium invasion of salivary gland and midgut epithelia. These experiments suggest a new strategy for the genetic manipulation of mosquito vectorial capacity.
Resumo:
The objective of this work was to quantify methane (CH4) emission using the sulfur hexafluoride (SF6) tracer technique, by dairy cattle on pasture in Brazilian tropical field conditions. Measurements were performed in the rainy season, with Holstein and Holstein x Zebu crossbred, from lactating and dry cows and heifers grazing fertilized Tobiatã grass, and heifers grazing unfertilized Brachiaria grass. Methane and SF6 concentrations were determined by gas chromatograph. Methane emissions by lactating cows varied from 13.8 to 16.8 g/hour, by dry cows from 11.6 to 12.3 g/hour, by heifers grazing fertilized grass was 9.5 g/hour and by heifers grazing unfertilized grass varied from 7.6 to 8.3 g/hour or 66 to 72 kg/head/year. Methane emission per digestive dry matter intake (DMDI) varied from 42 to 69 g/kg DMDI for lactating cows, 46 to 56 g/kg for dry cows, 45 to 58 g/kg for heifers grazing fertilized grass and 58 to 62 g/kg for heifers in unfertilized grass pasture. The CH4 emission measured on dairy cattle feeding tropical grasses was higher than that observed for temperate climate conditions.
Resumo:
In this study we evaluated the frequency of enteroparasites in pet dogs and their association with age, sex and breed, as well as the efficiency of the Willis-Mollay, Faust, Sedimentation and Direct exam methods. By these methods we processed 401 fecal samples. The samples were positive in the following percentages: Ancylostoma spp. (53.1%), Toxocara canis (20.7%), Cystoisospora ohioensis (15.7%), Trichuris vulpis (3.7%), Dipylidium caninum (2.5%) and Taenia spp. (1.0%). Toxocara canis (67.3%) and C. ohioensis (47.3%) showed higher positivity in the puppies. The Willis-Mollay technique was more efficient in the diagnosis of Ancylostoma spp. and T. canis eggs. The Direct method was the least efficient. It was found that the majority of the cases of D. caninum were diagnosed by the Sedimentation method (8=2.0%), while for T. vulpis Willis-Mollay (12=3.0%) and Sedimentation (13=3.2%) were more efficient. In view of these results, we can recommend the association of Willis-Mollay and Sedimentation methods for the diagnosis of gastrointestinal helminths. Due to the elevated occurrence of Ancylostoma spp. and T. canis, which are involved in zoonotic diseases, it becomes necessary to apply more efficient prophylaxis of canine intestinal parasitosis at the City of Araçatuba, state of São Paulo.
Resumo:
Toxoplasmosis is a zoonosis caused by Toxoplasma gondii, a coccidian protozoan of worldwide distribution. The seroprevalence in canine population can be an alternative for measuring T. gondii urban spreading. A total of 780 blood samples from dogs were collected, during the yearly anti-rabies campaign, carried out by the Department of Veterinary Hygiene and Public Health, School of Veterinary Medicine and Animal Husbandry (FMVZ), São Paulo State University, UNESP, together with the county health authorities, in August 1999. Using Indirect Fluorescent Antibody Test (IFAT) for detecting antibodies anti-T. gondii in the sera samples, we observed that 258 dogs (33.1%) were positive. The associations between the serological results and the epidemiological variables were studied. Statistically significant differences were not found regarding sex (32.2% male and 34.3% female reactors). Dogs without a defined breed showed seropositivity statistically higher than the pedigreed group. The occurrence of infection was considered higher with age.
Resumo:
In the present study, we evaluated three techniques, mouse bioassay, histopathology, and polymerase chain reaction (PCR) to detect Toxoplasma gondii infection in tissues from experimentally infected pigs. Twelve mixed breed pigs, seronegative for T. gondii using an indirect immunofluorescent antibody test (IFAT), were used. Ten pigs were infected with 4 × 104 VEG strain oocysts, and two were maintained as uninfected controls. Animals were killed 60 days pos infection. Muscle (heart, tongue, diaphragm, and masseter) and brain samples were collected to investigate the presence of T. gondii tissue cysts by the different assay methods. For the bioassay, samples of brain (50 g) and pool of muscle samples (12.5 g of tongue, masseter, diaphragm, and heart) were used. PCR was performed using Tox4 and Tox5 primers which amplified a 529 bp fragment. The DNA extraction and PCR were performed three times, and all tissue samples were tested individually (brain, tongue, masseter, diaphragm, and heart). For histopathology, fragments of tissues were fixed in 10% of buffered formal saline and stained with HE. Histopathological results were all negative. PCR showed 25/150 (16.6%) positive samples, being 17/120 (14.1%) and 8/30 (26.6%) from muscle, and brain tissues, respectively. Tissue cysts of T. gondii were identified by mouse bioassay in 54/98 (55.1%) samples, being 31/48 (64.6%) from muscle samples, and 23/50 (46.0%) from brain samples. Toxoplasma gondii isolation in muscle samples by mouse bioassay was higher than in PCR (P < 0.01). Results indicate that DNA from pig tissues interfered with 529-bp-PCR sensitivity, and mouse bioassay was better than PCR in detecting T. gondii in tissues from pigs. © 2006 Elsevier Inc. All rights reserved.
Resumo:
Bovine babesiosis is a blood parasitic disease. In Brazil it is caused by B. bovis and B. bigemina protozoa, both of which reveal the Boophilus microplus tick as the only biological vector. Animal samples were collected at Experimental Study Farm of Curraleiro Cattle (ESFC) in 2001 (n=117) and 2003 (n=113). The detection of antibodies against B. bovis and B. bigemina was carried out by ELISA-indirect method. This research was aimed at studing seroepidemiological aspects of bovine babesiosis in a Curraleiro herd, as well as obtain information about babesiosis stability in this population and relate the results with available climactic and management information. The occurrence rate of positive animals was 92.3% for B. bovis and 83.8% for B. bigemina in 2001; in 2003 it was 92.9% and 66.4%, respectively. There was a significant difference between seropositive frequency and age in 2003; such a frequency decreased with ageing. It was possible to conclude that despite environmental conditions and chemical controls against endo and ectoparasites, these animals were exposed to Babesia spp and they found themselves in a situation of enzootic stability for babesiosis.
Resumo:
This review present a discussion abouth the tannins. The tannins are compounds that have the ability to bind other macromolecules, reducing their availability to animal metabolism. This characteristic can be benefic or deleterious, depending on the tannin concentration degree in the plant and its structure. Positive effects are mainly related with a better use of the dietary protein and an increased efficiency of microbial protein synthesis in the rumen. The use of tannins to reduce ruminal methane emission has been subject of current researches, firmly indicating a decrease of ruminal methanogenesis. However, many of these studies, carried out to evaluate the effects of tannins on forage fermentation and animal metabolism, are based on legume plants, so their results can not be surpassed to studies concerning tanniniferous grasses. By improving the characterization of the profile and reactivity of tannins in tanniniferous forages, such as some sorghum hybrids, as well as conducting experiments to demonstrate the effects of tannins on animal metabolism and performance, the real potential of forages with tannin will be enlightened.
Resumo:
Aim: The purpose of this review is to present the potential for the incorporation of ozone therapy into the practice of dentistry. Background: Ozone gas has a high oxidation potential and is 1.5 times greater than chloride when used as an antimicrobial agent against bacteria, viruses, fungi, and protozoa. It also has the capacity to stimulate blood circulation and the immune response. Such features justify the current interest in its application in medicine and dentistry and have been indicated for the treatment of 260 different pathologies. It can be used for the treatment of alveolitis as a replacement for antibiotic therapy, as a mouthwash for reducing the oral microflora, as well as the adherence of microorganisms to tooth surfaces. Ozone has been shown to stimulate remineralization of recent caries-affected teeth after a period of about six to eight weeks. Conclusion: The future of ozone therapy must focus on the establishment of safe and well-defined parameters in accordance with randomized, controlled trials to determine the precise indications and guidelines in order to treat various medical and dental pathologies. Scientific support, as suggested by demonstrated studies, for ozone therapy presents a potential for an atraumatic, biologically-based treatment for conditions encountered in dental practice.
Resumo:
The 30, 45 and 60 day-old elephant grasses were evaluated by monitoring their nutritional profile and DM (DMI) and NDF (NDFI) intake by crossbred lactating cows in a 3 × 3 Latin square trial, where the split-plots were the rumen evacuation times: 0, 2, 4 and 6 h after meal. Chemical composition, in vitro dry matter digestibility and ruminal content ranged with grass age. Means (in kg/cow/day) of DMI and NDFI of 30 day-old grass (8.0 and 5.3) were lower than those of grasses with 45 days (10.0 and 6.6) and 60 days (11.0 and 7.3). The maximum of rumen fill was observed at 4:22, 3:55 and 3:49 hours after feeding for treatments with 30, 45 and 60 day-old elephant grass, respectively. Rumen fill did not limit the DMI and NDFI of elephant grass, but the dry matter intake of 30 day-old grass may be affected by the wet content.
Resumo:
The objective of this work was to evaluate the effect of nitrogen sources, using sugarcane supplemented with urea, corn gluten meal-60 or soybean meal. It was evaluated Intake, total and partial apparent digestibility were evaluated using four rumen and duodenal cannulated crossbred steers. The treatments were evaluated in a 4 × 4 Latin square design. The total feces were collected to determine the apparent digestibility on the total intestinal tract. The indigestible acid detergent fiber (iADF) was used as marker of duodenal flux to determine ruminal and intestinal digestibility and dry matter daily flux. The DM, OM, CP, EE, DE, NDF, ADF and TC intakes and digestibility rates were influenced by nitrogen sources, and lower intake was observed in animals fed exclusively with cane sugar compared to animals fed the other experimental diets. Meanwhile the sources of nitrogen did not affect the total digestible nutrients (TDN) values. The RDP sources did not affect the total, ruminal, and intestinal nutrients apparent digestibility. However, the total, ruminal, and intestinal dry matter, and protein apparent digestibility were affected by the RDP sources.
Resumo:
The carbohydrates provide 50 to 80% of the dry matter of grain and roughage and can be divided into structural (cellulose, hemicellulose) and non-structural (starch, pectin and sugars). The non-structural carbohydrates are primarily digested in the rumen and its dynamic process is a sequence for the supply of nutrients to the intestine. The quality and quantity of products resulting from ruminal fermentation are dependent on the type and activity of microorganisms in the rumen influenced by the type of food processing and that are subject of cereal grains that make up the diet. The NSC escape of rumen fermentation to be digested into glucose in the small intestine by pancreatic enzymes of origin (α-amylase) and intestinal mucosa (maltase and isomaltase). Starch is the most important energy supplier of cereals, which are important components of diets for intensive production of milk and meat.
Resumo:
Visceral Leishmaniasis (VL) is a zoonosis caused by Leishmania spp. protozoa. Dog is the main parasite's reservoir, especially in urban areas. Indirect Immunofluorescent Antibody Test (IFAT) is commonly used for canine visceral leishmaniasis (CVL) diagnosis, by detection of antibodies against the parasite. However, Trypanosoma cruzi (T.cruzi) cross reactions can occur in serological diagnosis. In order to evaluate the occurrence of cross reactions between antigens of Leishmania spp. and T.cruzi, 150 blood samples of CVL epidemiological inquiry positive dogs were collected and sera were tested by IFAT. Dogs were culled at Zoonosis Control Center of Bauru (SP), an endemic area for VL. Another 150 dogs' blood samples were collected in Botucatu (SP), a non endemic area for LV, and sera were also tested by IFAT. Serum samples of dogs from Bauru were positive, both for Leishmania spp. and for T. cruzi, showing high cross-reactions incidence, reinforcing the need of diagnosis confirmation by other tests. Serum samples of dogs from Botucatu demonstrated low prevalence of positive results by IFAT, both for Leishmania spp. and T.cruzi. However, despite the low number of positive serological results for these parasites, the epidemiological and serological investigation for LV and Chagas disease in dogs from Botucatu must be kept, considering the importance of dog as domestic reservoir for both parasites.
Resumo:
Toxoplasma gondii is the causative intracellular protozoan of toxoplasmosis in human being and animals. Members of the Felidae family are considered the single definitive host for the infection; both wild and domestic cats are able to excrete oocysts in the environment. Wild cats maintained in captivity may serve as source of infection for other clinically susceptible animals in the same environment. The aim of this study was to determine the frequency of T. gondii IgG antibodies in 57 neotropical felids (1 Leopardus geoffroyi; 3 Puma yagouaroundi; 17 Leopardus wiedii; 22 Leopardus tigrinus; and 14 Leopardus pardalis) kept at the Bela Vista Biological Sanctuary, Itaipu Binacional, Southern Brazil, by the modified agglutination test (MAT) using titer 16 as cut-off point. Seropositivity was observed in 38/57 (66.67%; 95% CI 53.66-77.51%) samples, with higher frequency in ocelots (71.43%). Wild-caught felids were three times more likely to be infected when compared to zoo-born animals (P≤ 0.05) and age of wild-caught animals (P= 0.6892; 95% CI. = 0.7528-1.66) was not significant as a risk factor for the infection, the same occurring with zoo-born animals (P= 0.05; 95% CI. = 0.6267-24.052). These results suggest that, despite efforts to control T. gondii infection in zoo facilities, such as individual pens, hygiene monitoring, veterinary care and pre-frozen meat offered as food, non-domestic felids kept in captivity, particularly the wild-caught specimens, may be invariably exposed to infection due to other environmental sources. © 2010 Elsevier B.V.