A literature review of equine piroplasmosis after an episode of acute babesiosis in a Dutch Standardbred foal after a stay in Normandy

Piroplasmosis, a disease endemic to most tropical and subtropical areas, appears to be spreading to more temperate zones. This article gives a review of equine piroplasmosis and describes an acute case of infection with Babesia caballi in a Dutch Standard bred foal after a short stay at a stud in Normandy (France). A 3-month-old stallion foal was presented with lethargy, fever of 41 degrees C, and pale mucosal membranes. Haematology revealed a low packed cell volume (14 l/l) leucytosis (25 G/l) and a high blood urea nitrogen concentration (20.1mmol/l). Infection with B. caballi was diagnosed on the basis of Giemsa staining blood smears and was confirmed by polymerase chain reaction in combination with RLB. Treatment with imidocarb dipropionate and a blood transfusion resolved the haemolytic crisis.     

Usefulness of the Detached Pod Test for Assessment of Cacao Resistance to Phytophthora Pod Rot

The detached pod test by spray method (DPT-SM) was developed to facilitate the screening of cacao genotypes for resistance to Phytophthora pod rot (PPR) caused by Phytophthora palmivora. The test has been adopted in many cacao research institutes, and it is imperative that its validity be assessed. In this study, 40 genotypes from various cacao groups were selected and screened for resistance to PPR by DPT-SM and field observations. Significant variation was observed in the reactions of the selected accessions based on the disease rating scale for DPT-SM and the percentage pod rot from field observations. A correlation coefficient of 0.68 (P<0.001) was observed between the results of year-1 and year-2 field observations. However, relatively lower correlation values were obtained between year-3 and year-1 (r=0.32; P=0.041) and year-3 and year-2 (r=0.35; P=0.025) field observations. A higher level of susceptibility was observed in the third year of field observations (63%) than in the first (15%) and second (25%) years. This suggests that the predisposing factors for PPR were unstable between the years of field observations. Data obtained from the Trinidad and Tobago Meteorological Services showed that the rainfall in November of the third year was higher than the amounts of rainfall in November of the first 2 years of field observations. This month marks the beginning of the main pod harvest season (November–February) and the high rainfall in November of the third year, and the presence of large number of mature pods may account in part for the increase in PPR in the third year of field observations than in the first 2 years. This shows that absolute reliance could not be placed on a single year of field observations in determining clonal resistance to PPR. A correlation coefficient of 0.59 (P<0.001) was obtained between the result of year-2 field observations and DPT-SM. Relatively lower correlation values were observed between DPT-SM and year-1 (r=0.55; P<0.001) and year-3 (r=0.44; P=0.005) field observations. The result of DPT-SM, however, shows a higher correlation (r=0.66; P<0.001) with the average of years 1–3 field observations. This suggests that a stronger association may exist between the result of DPT-SM and the cumulative data on field observations for a period longer than 3 years. The correlation (r=0.66; P<0.001) observed in this study confirms the usefulness of DPT-SM as an effective method of assessing clonal resistance to PPR and predicting field reaction in the long term. Since field observations are labour intensive and expensive to conduct on a yearly basis, the DPT-SM offers a cheaper and effective means of assessing clonal resistance to PPR. Being a non-destructive inoculation method, the DPT-SM provides a suitable option for cacao collections in genebanks to be assessed. It is also a cost-effective method for use in cacao breeding programmes. Based on its reliability, the DPT-SM has been adopted in the CFC/ICCO/IPGRI cocoa project ‘Cocoa Germplasm Utilization and Conservation: A Global Approach’ for the assessment of cacao resistance to PPR in several cocoa producing countries.     

Evaluation of enzyme-linked immunosorbent assay for quantitation by subclass for bovine antibodies.

The enzyme-linked immunosorbent assay (ELISA) was evaluated for use in the quantitative measurement of bovine immunoglobulin IgG1 and IgG2 antibodies. A method for standardization was devised in which IgG1 or IgG2 was directly adsorbed to polystyrene tubes and the actual degree of binding was calculated by using different input amounts of 125I-labeled IgG1 or IgG2. Values for quantity of IgG1 antibodies to human serum albumin were only slightly higher when measured by the ELISA than when measured by quantitative precipitation although the value measured by the ELISA for IgG2 antibodies was twice that determined by quantitative precipitation. This discrepancy could result from conjugate cross reactivity, differences in affinity between antibodies of the 2 subclasses, or the occurrence of IgG2 nonprecipitating antibodies. The danger of overlooking subclass anti-globulin cross reactivity because of the failure to detect it by immunoprecipitation, also is illustrated. In addition, only enzyme-antibody conjugates prepared with specifically purified antibodies were effective, and reproducibility of individual data points required that 4 replicate determinations be performed. Advantages, pitfalls, and limitations of the ELISA are discussed.     

Ultrastructural features of Mycoplasma gallisepticum in tracheal explants under transmission and stereoscan electron microscopy

Ultrastructural features of Mycoplasma gallisepticum in tracheal explants were examined using the transmission and stereoscan electron microscope. The organisms were characteristically cocco-bacilliform except when in close contact with the host cells when they assumed an elongated and irregular form characteristically terminating in a bleb which was often embedded in the cell surface. In such organisms there were peripherally aligned fibrillar structures oriented towards the bleb which may have a functional relationship with a probing or moving habit of the mycoplasma.     

The effect of Escherichia coli endotoxin on lysosomal enzymes in the domestic fowl.

During the 2 h following the injection of chickens (aged nine to 11 weeks) with endotoxin isolated from a pathogenic strain of Escherichia coli (O78) there was a transient rise in the activity of acid phosphatase, aryl sulphatase and beta-glucuronidase in the plasma, suggesting increased release of these enzymes from lysosomes. This was followed by a fall in their activity which may have been due largely to stabilisation of the lysosomal membrane brought about by increased secretion of adrenocortical hormones and/or accelerated removal of the enzymes from circulation by the reticuloendothelial system.     

Rectal hemorrhage associated with vascular ectasia in a young dog.

Rectal bleeding in a 7-month-old 13-kg sexually intact female mixed-breed dog was determined to be associated with vascular ectasia of the small intestine, descending colon, rectum, and anus. Microscopically, the telangiectasia was associated with lymphangiectasia and focal ulceration. Surgical intervention resulted in incomplete resection of the lesion and only temporary amelioration of clinical signs. The dog's age was compatible with a congenital origin for the defect, but an acquired cause could not be excluded.     

Halothane-induced malignant hyperthermia in Irish pig breedsHyperthermie maligne induite par l'halothane dans les races porcines irlandaisesHalothan induzierte maligne hyperthermie bei Irischen schweinerassen

A total of 567 young pigs entering one of the national testing stations were tested for sensitivity to halothane between October 1976 and May 1978. They included 443 Landrace, 76 Large White and 48 Irish Welsh. The average weight at testing was 25.6 kg. A total of 24 pigs reacted positively to the test, 21 (4.6%) of the Landrace and 3 (6.3%) of the Irish Welsh. No reactors were found in the Large White breed.Meat quality estimates in the form of the pH in the longissimus dorsi muscle 45 min post-mortem (pH₁) were recorded on the 324 slaughtered pigs. Reactor pigs (ten) had significantly lower values than non-reactors, indicating a greater tendency to develop quality problems such as pale, soft, exudative (PSE) meat. There was an indication that reactor pigs might have slightly reduced daily gains and lower backfat thickness.