Comparison of slot blot nucleic acid hybridization, immunofluorescence, and virus isolation techniques to detect bluetongue virus in blood mononuclear cells from cattle with experimentally induced infection.

A slot blot hybridization technique was applied for detection of bluetongue virus (BTV) in blood mononuclear cells (BMNC) obtained from cattle with experimentally induced infection. This technique lacked sensitivity to detect the viral nucleic acid directly in clinical specimens. When aliquots of mononuclear cells from these cattle were cultivated in vitro for 10 days to amplify virus titer, only 33.3% of the samples collected during viremia gave a positive signal in the slot blot hybridization format. By contrast, results for 34.3% of noncultured and 63.3% of cultured mononuclear cell samples collected during viremia were positive by immunofluorescence. The average number of infected cells, as detected by immunofluorescence in the noncultured mononuclear cell samples, was 1 to 5/300,000, and was usually > 10/300,000 in the cultured cell samples. Virus was isolated from all postinoculation blood samples obtained from 4 heifers that were seronegative at the time of inoculation, but was not isolated from any of the preinoculation samples, or from any of the postinoculation samples obtained from 2 heifers that were seropositive at the time of inoculation. When virus isolation was attempted from separated mononuclear cells in 2 heifers, 43.7% of the noncultured and 87.5% of the cultured samples had positive results.     

Laryngeal paralysis in immature and mature dogs as one sign of a more diffuse polyneuropathy

Six dogs with laryngeal paralysis had clinical, electrophysiologic, and pathologic evidence of a more generalized polyneuropathy. Three of the dogs were young Dalmatians, one was a young Bouvier des Flandres, and two were older, large-breed dogs. The results of this study suggest that laryngeal paralysis in dogs may frequently be one clinical sign of an underlying, more generalized polyneuropathy. Two forms of this generalized polyneuropathy may exist: an early form, as seen in young dogs with congenital or hereditary disease, and a delayed-onset form that is usually found in older dogs with so-called idiopathic laryngeal paralysis, some of which may have hypothyroidism.     

Influence of 17-α-Methyltestosterone on Red Tilapia Under Two Thermal Regimes

Fingerling red tilapia ( Oreochromis mossambicus ± O. niloticus ) were orally administered 17-α-methyltestosterone (MT) under a warmwater (27.0 ± 0.5 C) and coolwater (21.5 ± 0.5 C) thermal regime. In the warmwater experiment, fish received either 0, 1, 5, 10, 30, 60, or 100 mg MT/kg feed for 75 days. In the coolwater experiment, fish received 0, 10, or 60 mg MT/kg feed for 75 days followed by a 34 day withdrawal period. After 75 days, fish receiving 60 mg MT/kg feed (best treatment) in the warmwater and coolwater experiments exhibited significantly higher growth rates than controls by 35.3 and 45.8%, respectively. Likewise, feed conversion among groups receiving 60 mg MT/kg feed in the warmwater and coolwater experiments were significantly better than the controls (1.14 versus 1.30 and 1.44 versus 1.77, respectively). During the withdrawal period, no significant differences in growth rates or feed conversion were observed between the control and treatment groups. MT treatment significantly affected the body composition (whole body and empty carcass) of the red tilapia in both experiments, elevating percent moisture and protein values, but depressing percent fat values. Results demonstrated that incorporation of MT into fingerling diets offers potential for extending the period when tilapias actively feed and grow in temperate climates.     

Mangroves as indicators of coastal change

In view of the unique biological characteristics of mangroves, it is interesting to assess the extent to which these ecosystems can be used as indicators of coastal change or sea-level rise. From recent studies of mangrove mortality at several locations (including Guiana, Gambia, Côte d'Ivoire, Kenya, India and Bangladesh), it appears that these coastal ecosystems are so specialized that any minor variation in their hydrological or tidal regimes causes noticeable mortality. Each species of mangrove (but particularly those belonging to the genera Rhizophora, Bruguiera, Sonneratia, Heritiera and Nypa) occurs in ecological conditions that approach its limit of tolerance with regard to salinity of the water and soil, as well as the inundation regime. If the duration of daily immersion were to be modified by tectonic, sedimentological or hydrological events, the species either readjusts to the new conditions or succumbs to unsuitable conditions. Consequently, the use of remote sensing data for mangrove ecosystems offers excellent potential as a tool for monitoring coastal change.     

The effect of exploratory laparotomy on the serum and peritoneal haptoglobin concentrations of the pony.

Serum haptoglobin concentration was used as an indicator of the acute phase response in ponies undergoing exploratory laparotomy. Preoperative, 1 h intraoperative, 3 h, 6 h, 12 h and 24 h postoperative blood samples and 48 h postoperative peritoneal fluid samples were obtained for haptoglobin analysis. A spectrophotometric assay based on cyanmethemoglobin binding capacity (CyanBC) was used to determine haptoglobin concentrations. The preoperative reference range for serum haptoglobin concentrations in these ponies was 25-60 mg CyanBC/dL. Intraoperative and 3 h postoperative blood samples had decreased haptoglobin concentrations when compared to preoperative values. Serum haptoglobin concentrations began to rise by the 6 h postoperative sample and were generally elevated above preoperative values by the 24 h postoperative sample. Two of the ten ponies had mild signs of postoperative colic which were associated with twofold elevations in serum haptoglobin concentrations and fivefold elevations in peritoneal fluid haptoglobin concentrations.     

A BOOST TECHNIQUE FOR IRRADIATION OF MALIGNANT CANINE NASAL TUMORS

Eighteen dogs with malignant nasal cavity tumors were treated with radiation therapy, including a boost technique. Three 3:0 Gy boost doses were added to a treatment protocol consisting of sixteen 3.0 Gy daily fractions, bringing the total dose to 57 Gy. This boost technique was implemented without an associated increase in overall treatment time by giving the boost doses on a twice-a-day basis. Boost doses were given during the first half of the radiation therapy period. The treatment was completed as planned in 16 of the 18 dogs; two dogs received lower doses (51 and 54 Gy). Median survival was 177 days, poorer than in some other reported studies of nasal tumor irradiation. Acute effects were unacceptable, with 11 of the 18 dogs developing severe mucositis, desquamation, edema, swelling, and pruritus. The extensive nature of the acute reactions compromised assessment of the effect of the increased radiation dose on the tumor. Although there is justification for assessing more aggressive radiation protocols in canine nasal tumor patients, total doses approximating 60 Gy can not be given as described because of the inability of acutely responding normal tissues to compensate.     

Surgical treatment of lameness.

Digital diseases are commonly seen in cattle. Cattle affected by digital disorders do not always respond to conservative therapy and require surgery. Surgical procedures for the common digital disorders are described, with emphasis on the different approaches to the distal interphalangeal joint.