A COMPARISON OF MANUAL AND AUTOMATIC ULTRASOUND-GUIDED BIOPSY TECHNIQUES

A manual, ultrasound-guided biopsy technique was compared to a new automatic method using a new biopsy device. The liver and the left kidney of 10 dogs were biopsied using the two methods. The specimens from the biopsies were compared for size and quality. Results demonstrate that larger and higher quality samples were obtained with the new automatic method.     

Epidemiological studies of pig diseases: 1. Use of French protocols for risk factor assessment to predict the health status of Australian herds

Objective To determine in Australian pig herds the accuracy of French protocols for risk factor assessment.
Procedure Data on health indicators and risk factors were collected for three syndromes, 'pre-weaning diarrhoea', 'post-weaning diarrhoea' and 'respiratory problems', using the French protocols. The protocols were used on 118 occasions in 32 Western Australian pig herds during 3 years (1988 to 1991).
Results There was a wide variation in pre-weaning performance, for example growth rate was 107 to 273 g/day (< 200 g/day in 33% of herds). Respiratory lesions at weaning were associated with poor pre-weaning performance. Post-weaning (21 days after weaning) growth rate was 114 to 408 g/day (< 250 g/day in 54% of herds). In the grower herds, 91% of herds had pneumonia, and growth rate was 439 to 625 g/day (< 550 g/day in 54% of herds). Pleurisy as well as pneumonia was associated with reduced growth rate. The risk factor most closely associated with respiratory health status was air volume per pig.
Conclusion Risk factors were most accurate at predicting the health status in post-weaning problems. A weaning weight of at least 7.9 kg and weaning age of 30 days optimised weaner performance. Stocking densities and shed designs providing at least 3 m³ air volume and 0.6 m² floor space per pig throughout the growing phase should be considered for an improved respiratory health status. Australian pig sheds often do not provide a satisfactory environment for optimum health. The technique of risk factor assessment as an aid to the maintenance of health in pig herds is applicable in Australia, but further research is necessary to determine the most important Australian risk factors.     

Changes in Ovarian Follistatin Levels During the Oestrous Cycle in Sheep may Serve as an Intraovarian Regulator

The expression and concentration of follistatin and activin change during oestrous cycle suggesting their involvement in the regulation of follicular development. The aim of this study was to determine the level, source and potential role of follistatin in the sheep ovary. Follistatin in ovarian venous blood, measured by radioimmunoassay, remained at its low level from follicular phase (day ?1 and 0) to mid‐luteal phase (days 11–13) phase but were significantly elevated during the late luteal phase (days 14 and 15) when corpora lutea underwent regression. Western blot analyses of follicular fluid at day 15 of the cycle showed two strong bands at 42 and 45 kDa and weakly stained bands at 39 and 31 kDa. At day 0, these bands became weaker and the 39 kDa band became undetectable. However, there were no differences in follistatin concentrations between ovaries with and without functional corpus luteum (CL) during the whole luteal phase. In addition, although the ovaries of Booroola ewes normally contain more corpora lutea than those of normal merino ewes, follistatin concentrations in both jugular and ovarian venous blood were similar in Booroola and normal merino ewes. It is concluded that the secretion of follistatin from the ovary is not related to the formation of CL or high ovulation rate of Booroola ewes. The elevation in follistatin concentration in follicular fluid and ovarian blood during late luteal phase may indicate a dual role of follistatin in the luteolysis of existing CL and development of new follicle cohort.     

Dicoumarol toxicity in cattle associated with ingestion of silage containing sweet vernal grass (Anthoxanthum odoratum)

A diagnosis of dicoumarol toxicity in a herd of Friesian cattle was made following investigation of the deaths of three mature cows and eleven yearling heifers. Affected stock had been fed wrapped, bailed silage containing approximately 90% sweet vernal grass ( Anthoxanthum odoratum ). Sweet vernal grass contains coumarin, which can be converted to dicoumarol, a vitamin K antagonist, through the action of moulds. Most deaths were preceded by lethargy, severe anaemia and subcutaneous and internal haemorrhage. Dicoumarol toxicosis was suspected based on clinical signs, necropsy findings and prolonged prothrombin and activated partial thromboplastin times. Dicoumarol analysis of blood from affected animals and silage confirmed the diagnosis.     

Prevalence of Rickettsia felis DNA in the blood of cats and their fleas in the United States

Rickettsia felis is associated with fever, headache, myalgia, and macular rash in some infected humans and has been detected in the cat flea (Ctenocephalides felis) in many countries around the world. While some naturally exposed cats have been assessed for antibodies against R felis, to our knowledge, no one has reported use of polymerase chain reaction (PCR) to attempt to amplify R felis DNA from client-owned cats and the fleas collected from them. In this study, we assayed 92 pairs of cat blood and flea extracts from Alabama, Maryland and Texas, using PCR assays that amplify a region of the citrate synthase gene (gltA) and the outer membrane protein B gene (ompB). Of the 92 pairs, 62 of 92 (67.4%) flea extracts and none of the cat blood samples were positive for R felis DNA.     

Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity

The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages.