Toxoplasma gondii and Leptospira spp. infection in free-ranging armadillos

Armadillos are primitive mammals used as food, mostly in rural areas. These animals may be sources of toxoplasmosis and leptospirosis infection for humans, but there is little information about their potential risk as reservoirs. In order to determine the prevalence of armadillos infected by Toxoplasma gondii and Leptospira spp., serum samples of 31 nine-banded armadillos (Dasypus novemcinctus), three six-banded armadillos (Euphractus sexcinctus), two naked-tailed armadillos (Cabassous tatouay) and two long-nosed armadillos (D. hybridus), captured in the mid-west region of the state of S?o Paulo, were analyzed for leptospirosis using the Microscopic Agglutination Test (MAT-l), and for toxoplasmosis using the Modified Agglutination Test (MAT-t). Only 4/31 (12.90%) nine-banded armadillos were positive for T. gondii, while 3/31 (9.68%) nine-banded armadillos and 1/3 (33.33%) six-banded armadillos presented antibodies to Leptospira spp., demonstrating the potential risk of T. gondii and Leptospira spp. transmission to humans, mainly due the habit of eating the meat of these animals in rural areas.     

Platelet aggregation in dogs experimentally infected with Rickettsia rickettsii

Platelet aggregation studies were performed on nine Beagle dogs experimentally infected with Rickettsia rickettsia. Platelets from dogs with Rocky Mountain spotted fever tended to be more aggregable than controls.     

Evaluation of bone marrow cytology and stainable iron content in healthy adult llamas

Complete blood counts and sternal bone marrow aspirates were obtained from healthy adult llamas ranging in age from 2.5 to 8.4 years. Megakaryocyte numbers and erythroid and myeloid series maturation and morphology appeared similar to other mammalian species. The particles contained 50 to 75% marrow cells with the remainder composed of lipocytes and stromal cells. In samples with numerous particles and adequate cellularity, M/E ratios ranged from 0.9 to 2.9. Samples with higher white blood cell counts and fewer particles had higher M/E ratios. Eosinophils comprised 14.3% of the myeloid series which is higher than other domestic mammals. Hemosiderin granules were numerous in marrow particles.     

Isolation of a 14 kDa antigen from Taenia solium cyst fluid by HPLC and its evaluation in enzyme linked immunosorbent assay for diagnosis of porcine cysticercosis

A fraction with a major band of 14kDa was obtained from crude cyst fluid of Taenia solium cysticerci by 2-step chromatography. A first fraction isolated by gel filtration (Sephacryl S-300 high resolution) was purified using an anion exchange column (Mono Q HR 5/5) on high performance liquid chromatography. Evaluation of the analytic sensitivity of this fraction (F3) was carried out in an antibody enzyme linked immunosorbent assay (Ab-ELISA-F3) using serum samples from pigs experimentally infected with different doses of T. solium eggs. The cross-reactivity of F3 was evaluated with serum samples from pigs that were naturally or experimentally infected with Taenia hydatigena, Taenia saginata asiatica, Fasciola hepatica, Trichinella spiralis, Metastrongylus apri, Trypanosoma congolense and Sarcoptes scabiei, and with serum samples of rabbits hyper-immunised with metacestode cyst fluid of T. hydatigena and T. solium. Antibody titres of lightly or heavily infected pigs differed in their kinetics. However, the increase in F3-specific antibodies could not be related to the infection level. Analysis of the specificity of the F3 showed that serum samples of pigs infected with other parasites did not recognise this antigen. Cross-reaction with T. hydatigena occurred in ELISA using cyst fluid as antigen, but the F3 antigen fraction was not recognized by rabbit hyper-immune serum samples to T. hydatigena. Evaluation of the diagnostic sensitivity and specificity of the Ab-ELISA-F3 was done by a non-parametric receiver operating characteristic (ROC) analysis using 66 serum samples from Zambian village pigs. The total number of cysticerci of these pigs was determined by dissection (28 pigs harboured T. solium cysticerci and 38 were negative at dissection). In addition, 58 serum samples from Cameroonian pigs (28 pigs from cysticercosis-free farms and 30 pigs with cysticerci at tongue inspection) were used in a separate ROC analysis. The results from the ROC analysis yielded a low diagnostic value (area under ROC curve=0.48) with the sera from the Zambian pigs while a relatively high diagnostic value was obtained with the sera from Cameroonian pigs (area under ROC curve=0.78). The main factor contributing to a low diagnostic value based on the Zambian serum samples seemed to be the false-positive reactions that were likely caused by the occurrence of transient antibodies in the non-infected animals.     

Effect of species of cool-season annual grass interseeded into Bermudagrass sod on the performance of growing calves

Two experiments were conducted to evaluate the effect of species of cool-season annual grass on the growth of stocker cattle over 3 yr. In Exp. 1, the small grains (SG) oat (O), rye (R), and wheat (W), or combinations of SG and annual ryegrass (RG), were interseeded into Bermudagrass sod in a completely randomized design with a 3 x 2 factorial arrangement of treatments. In Exp. 2, RG was planted alone or with O, R, triticale (T), or W in a completely randomized design. Pastures were planted in late October of each year, and seeding rates were 134.4 and 22.4 kg/ha for SG and RG, respectively. In Exp. 1, grazing was initiated on December 18. In Exp. 2, grazing was initiated on December 23 for SG pastures and January 21 or February 16 for RG pastures in yr 1 and on December 8 for all pastures in yr 2. Grazing was managed using the put-and-take method, in which additional calves were added as needed to maintain equal grazing pressure among pastures. In Exp. 1, no interactions (P > or = 0.28) were detected, so the main effects of SG species and RG addition are discussed. From December 18 to March 12, there were no differences in ADG (P > or = 0.17), whereas during the spring (from March 12 to May 7), addition of RG increased (P = 0.05) ADG. Using RG increased (P < or = 0.01) animal grazing-days/hectare and BW gain/hectare. Wheat tended (P = 0.08) to increase BW gain/hectare compared with the other SG, and O tended (P = 0.09) to produce less BW gain/hectare than the other SG. The treatment x year interaction was significant (P < or = 0.05) in Exp. 2. In yr 1, no differences (P = 0.25) were observed for ADG from December 23 to March 8, but during the spring grazing period (from March 8 to May 5), ADG of calves grazing TRG was less (P < or = 0.04) than that of those grazing RG, RRG, or WRG. The RRG combination produced more (P < or = 0.03) BW gain/hectare than ORG, RG, or TRG and tended (P = 0.06) to produce more BW gain/hectare than WRG. The WRG combination produced more (P < or = 0.05) BW gain/hectare than TRG and RG, and ORG tended (P = 0.09) to produce more BW gain/hectare than RG alone. Pastures planted to R or W produced more (P < or = 0.05) BW gain/hectare than RG alone or T. During yr 2, there were no differences (P > or = 0.44) in ADG, BW gain/hectare, or grazing-days/hectare. In conclusion, the choice of cool-season annual to establish is highly weather-dependent, but R and W are generally superior to other small grains, and RG is a necessary complement to SG when interseeding cool-season annuals into Bermudagrass sod.     

Rectal strictures in 19 dogs: 1997-2005

The etiologies for nonneoplastic rectal strictures in dogs included foreign bodies, postoperative formation, inflammatory disease, and congenital malformation. Sixteen of 19 dogs underwent balloon dilatation therapy, and 14 of these 16 dogs received intralesional triamcinolone injections. Following dilatation, clinical signs persisted in one dog, improved with continued medical therapy in five dogs, and resolved in nine dogs for the duration of their follow-up period (mean 18 months; median 12 months); one dog was lost to follow-up. Balloon dilatation and triamcinolone were parts of a treatment regimen that improved clinical signs in the majority of dogs diagnosed with nonneoplastic rectal strictures.     

Phase II clinical trial of combination chemotherapy with dexamethasone for lymphoma in dogs

Dogs with histologically confirmed lymphoma were treated with a 14-week induction chemotherapy protocol that included dexamethasone. A phase II clinical trial was done using a standard two-stage design. Complete remission occurred in 21 (88%) dogs, with a median initial progression-free interval of 186 days. Toxicity was mild and self-limiting in the majority of dogs.