Measurement of distal limb sub-bandage pressure over 96 hours in horses.

REASONS FOR PERFORMING STUDY: Currently, there is no objective information quantifying pressures exerted by distal limb bandages. OBJECTIVES: To quantify the pressure exerted by each compression layer, a polo wrap (DLP), a compression bandage (DLC), and to measure the effect of time on sub-bandage pressure. STUDY DESIGN: Longitudinal observational experiment. METHODS: A DLC construct included a cotton roll compressed with brown gauze and elastic layers and the DLP construct included a pillow pad compressed by a cloth wrap. Dorsal and lateral sensors were placed on the mid-metacarpus. In healthy horses, sub-bandage pressures were recorded during application (n = 8) and at scheduled time points over the 24 (n = 9) and 96 h periods (n = 8). A generalised linear model was used to evaluate associations between pressure and sensor location, bandage type and time (P<0.05). RESULTS: For the DLC, dorsal and lateral sensor pressures were 187 mmHg (95% CI 185-189 mmHg) and 142 mmHg (95% CI 133-151 mmHg). Combined sensor pressure after application of the brown gauze was 80 mmHg (95% CI 75-85 mmHg) and rose to 165 mmHg (95% CI 160-170 mmHg) after the elastic layer. Combined pressure at the end of the 96 h period was 135 mmHg (95% CI 123-147 mmHg). For the DLP bandage, location but not time was significant. Combined pressures ranged between 75 mmHg (95% CI 53-97 mmHg) and 85 mmHg (95% CI 63-107 mmHg). CONCLUSIONS: Pressure distribution was not uniform. The DLP pressures were maintained for a 24 h period. The DLC maintained high pressures for 96 h, but a significant decrease in pressure occurred between 6 and 12 h. Providing there are no other reasons to change a bandage, a 4 day interval between bandages may be appropriate if maintaining distal limb compression is the principal indication.

Comparison of sub-bandage pressures achieved by 3 abdominal bandaging techniques in horses.

REASONS FOR PERFORMING STUDY: Clinicians frequently place post operative abdominal bandages on horses undergoing laparotomies. Presently, no information exists on the amount of incisional support provided by these bandages. Determination of sub-bandage pressure provides a means of comparing the ability of different bandages to support incisions. OBJECTIVES: Determination of sub-bandage pressure over a 24 h period using 3 bandaging techniques. STUDY DESIGN: A randomised, crossover design using 9 healthy horses. METHODS: Horses were randomly assigned to a treatment regimen consisting of placement of 3 abdominal bandage types, namely an elastic bandage (ELA), the CM(TM) Hernia Heal Belt (CM) or a nylon binder (NYL). The sub-bandage pressures for each bandage were measured with the Picopress® compression-measuring system at 0, 2, 4, 6, 8, 12, 16, 20 and 24 h after application. RESULTS: No time and treatment interactions were observed, and bandage pressures were maintained within each treatment group over the 24 h period. Mean sub-bandage pressures were different between all treatment groups (P < 0.001) at 39 (95% confidence interval, 36.7-40.5 mmHg), 25 (95% confidence interval, 23.9-27.7 mmHg) and 5 mmHg (95% confidence interval, 4.1-7.8 mmHg) for CM, ELA and NYL bandages, respectively. Horses were more likely to lie down with the CM (P = 0.02) and ELA treatments (P = 0.0002) when compared with the NYL treatment. The ELA bandages were more likely to displace caudally compared with both CM and NYL bandages. CONCLUSIONS: The CM bandage was superior to both ELA and NYL bandages with regard to measured sub-bandage pressure over the 24 h period. The clinical significance of the differences in sub-bandage pressure between treatments cannot be determined by this study.

Comparison of fertility, regular returns-to-estrus, and calving interval between Ovsynch and CO-synch + CIDR protocols in dairy cows.

The main aims of the present study were to compare the pregnancy rate (PR), regular returns-to-estrus, and calving interval of a CO-Synch + controlled internal drug release (CIDR) device, commonly used to synchronize ovulations in beef cows, with the classical Ovsynch protocol in high-producing dairy cows. Holstein-Friesian cows (n = 128) from six commercial dairy herds, ≥40 days postpartum and not previously inseminated, were randomly assigned to one of two treatments. Cows submitted to Ovsynch protocol (group OS as control group; n = 66) received 10 µg of a GnRH analogue 7 days before and 48 hours after 25 mg PGF2α, followed by artificial insemination (AI) 16 hours after the second GnRH administration. Cows submitted to CO-Synch + CIDR (1.38 g of progesterone) inserted for 7 days beginning at the first GnRH administration (group CoS + CD; n = 62) had the second administration of GnRH concurrent with AI, 64 hours after CIDR removal/PGF2α administration. Nonpregnant cows with return-to-estrus between 18 and 24 days after first AI were reinseminated (second AI). Logistic regressions were used to analyze PR and returns-to-estrus. No effect of group or herd was observed in PR at first timed AI. However, the sum of cows pregnant at first AI and nonpregnant cows with regular returns-to-estrus and the total PR (first + second AI) were influenced by group treatment. Overall, cows of group CoS + CD (total PR = 56.5%) were 2.1 times more likely to became pregnant after AI and until first regular returns-to-estrus than cows of group OS. The calving interval was lower in group CoS + CD (425.9 ± 78.8 days; ±SD) than in group OS (475.3 ± 83.7 days). The CO-Synch + CIDR protocol was reliable to use in dairy herds and provided reproductive advantages when compared with Ovsynch protocol.

Histologic characterization of dilated cardiomyopathy in Estrela mountain dogs.

Dilated cardiomyopathy (DCM) is the second-most-important acquired cardiovascular disease in dogs (excluding heartworm disease in some geographic regions) and a major cause of morbidity and mortality in Estrela Mountain Dogs. The objective of this study is to describe the histologic features of DCM in Estrela Mountain Dogs, with special attention to the localization and quantification of attenuated wavy fibers (AWFs), fibrosis, and fatty infiltration. Myocardial samples from 10 areas were collected from the hearts of 10 dogs with DCM and 7 dogs without signs of cardiac disease-namely, the basal, middle, and apical portions of the free wall of both cardiac ventricles and the interventricular septum, as well as the left ventricular papillary muscle. In each sample, the presence or absence of AWFs was noted, and fatty infiltration and fibrosis were quantified. Fatty infiltration, fibrosis, and AWFs were observed in the myocardium of all dogs with DCM, in contrast to what has been described in other breeds. The left ventricular myocardium was the best tissue for diagnosis of DCM, based on these histologic features. The authors concluded that quantification of fibrosis and observation of AWFs in the left ventricular myocardium are useful in the histologic diagnosis of DCM in Estrela Mountain dogs.

Determination of the more adequate modified agglutination test cut-off for serodiagnosis of Toxoplasma gondii infection in sheep.

Toxoplasmosis is one of the most common food borne disease world-wide. Among food animals, sheep seems to having higher prevalence of Toxoplasma gondii infection. However, there is no consensus about the best cut-off for serodiagnosis in sheep. To estimate the more adequate cut-off value of Modified Agglutination Test (MAT) for serodiagnosis in sheep, a commercial ELISA kit was used as a golden standard. Evaluation of the optimal sensitivity and specificity was calculated using Youden's J-statistics. Values obtained were used to estimate the prevalence of sheep toxoplasmosis. One thousand four hundred and sixty seven blood samples were collected randomly from 160 farms from northern Portugal, representing approximately 10% of the ovine population from the region. All sera were tested for anti-T. gondii antibodies using the MAT. One hundred nine sheep (7.4%) presented a MAT titer > or = 1:80; 45 (3.0%) a MAT titer of 1:40; 97 (6.6%) a MAT titer of 1:20 and 1216 (83.0%) a MAT titer < or = 1:20. The best Youden's J-statistic was obtained at 1:20 titer (0.752), with 86.15% of sensitivity and 89.09% of specificity with negative and positive predictive values of 90.32% and 84.48% respectively, suggesting that the 1:20 was the most appropriate cut-off for serodiagnosis of toxoplasmosis in sheep. Assuming this cut-off, the prevalence of toxoplasmosis in the studied population was 17.1% and 92 (57.5%) of the 160 studied flocks having one or more positive sheep. Those results indicate that toxoplasmosis in Portugal should be considered in the differential diagnosis of abortions in sheep and neurological signs in lambs. Furthermore, while Portugal produces ovine meat for internal consumption and for exportation, isolation of T. gondii from ovine meat and further characterization of the isolates will be needed to understand the risk that ovine toxoplasmosis may represent for human health.

Characterization of Toxoplasma gondii isolates in free-range chickens from Portugal.

The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 225 free-range chickens (Gallus domesticus) from Portugal was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT) and found in 61 chickens with titers of 1:5 in 8, 1:10 in 6, 1:20 in 3, 1:40 in 23, 1:80 in 5, 1:160 in 4, 1:320 in 8, and 1:640 or higher in 4. Hearts, leg muscles, and brains of 15 seropositive (MAT 1:10 or higher) chickens were bioassayed individually in mice. Tissue from 38 chickens with titers of 1:5 or less were pooled and fed to a T. gondii-free cat. Feces of the cat were examined for oocysts, but none was found. Toxoplasma gondii was isolated from 16 of 19 chickens with MAT titers of 1:10 or higher. Genotyping of 12 of these 16 isolates with polymorphisms at the SAG2 locus indicated that 4 were type III, and 8 were type II. None of the isolates was lethal for mice. Phenotypically, T. gondii isolates from chickens from Portugal were different from those of T. gondii isolates from chickens from Brazil.

First isolation of Neospora caninum from an aborted bovine fetus in Spain.

Neospora caninum was isolated from the brain of a 6-mo-old aborted bovine fetus from Galicia, Spain. The fetal brain homogenate was inoculated intraperitoneally into cortisonized mice. The peritoneal exudate from the infected mice, along with mouse sarcoma cells (Tg180), was inoculated into a second group of mice, and parasites were harvested from the peritoneal exudate. The parasites were adapted to in vitro growth in Vero monolayers. The tachyzoites from the peritoneal exudate reacted positively with anti-N. caninum antibodies and not with anti-Toxoplasma gondii antibodies on indirect fluorescent antibody test. The tachyzoites were lethal to interferon gamma gene knock out (KO) mice and could be identified immunohistochemically in the tissues. The identity of the parasite was also confirmed by polymerase chain reaction amplification of N. caninum-specific fragments. The sequences of the amplified gene 5 fragments (GenBank AY494944) were found to be identical to that of an Austrian isolate of N. caninum but not to that of NC-1. This is the first isolation of viable N. caninum from Spain.

Determination of an optimized cut-off value for the Neospora agglutination test for serodiagnosis in cattle.

A definitive diagnosis of neosporosis in cattle implies the examination of the aborted fetus. However, in many instances fetal material is not available. Therefore, most diagnosis are based on serological tests. At the moment, there are no consensuses about the cut-off for serodiagnosis of neosporosis in cattle, for any test. The objective of the present study was to estimate the best cut-off for the Neospora agglutination test (NAT) for serodiagnosis in cattle. For that purpose, 246 serum samples from 4 groups of dairy cows (aborted Neospora positive; not aborted healthy; aborted other diseases and herds endemic neosporosis) were collected and antibodies anti-N. caninum were determined by NAT. Additionally, immunoblot (IB) was performed with sera from all cows of the endemic neosporosis group and the patterns of seroreactivity were contrasted with the NAT titers for this group of cows. Evaluation of the optimized sensitivity and specificity was calculated using Youden's J-statistics. The best Youden's J-statistic was obtained at 1:40 titer, presenting 100% of sensitivity and 90.4% of specificity with negative and positive predictive values of 100 and 75.0%, respectively. The comparison between NAT titers and the IB banding pattern support the results of the statistical analysis, i.e. titers of 1:40 and higher showed a complex pattern of bands, while titers lower than 1:40 did not precipitate any bands. These results indicate that 1:40 was an optimized NAT cut-off for serodiagnosis in cattle.

First confirmed case of Neospora caninum-associated abortion outbreak in Portugal.

In a dairy herd experiencing an abortion outbreak, 49% of the 119 cows were positive for Neospora caninum antibodies and the remaining 51% were seronegative. Using immunohistochemical analysis of foetal brain tissue, Neospora cysts and bradyzoite clusters were identified in two of the 15 aborted foetuses submitted for testing. Other agents that commonly cause abortions were not found. These results, coupled with neurological clinical symptoms in new-born calves, implicated N. caninum as the major cause of abortions in this dairy herd. This is the first report that associates N. caninum infection with bovine abortions in Portugal.