ULTRASONOGRAPHIC CHARACTERISTICS OF LIPIDURIA IN CLINICALLY NORMAL CATS

Echoes are frequently seen in the urinary bladder of cats during abdominal ultrasound. These have been attributed to hematuria, pyuria, crystalluria, and lipid. However, sonographic findings have not been previously correlated with urinalysis. We prospectively evaluated 40 clinically normal cats via ultrasound, serum chemistry, and urinalysis. Thin layer chromatography was performed on the urine to determine the amount (mg) of lipid subfractions including diacylglycerol, triglyceride, phospholipid, free fatty acid, cholesterol, and cholesterol ester. Ninety percent (36/40) of the cats in our population had sonographic echoes suspended in the urinary bladder, with most having a subjective score of mild echoes (n = 20). None of the sonographic echoes were gravity dependent or caused distal acoustic shadowing, reverberation, or twinkle artifact. Of the cats with sonographic echoes in the urine, 66% (24/36) had no significant findings on urinalysis other than the presence of lipid. The total amount of subjective sonographic echoes was not significantly related to the total amount of fat measured on thin layer chromatography or the number of lipid droplets seen on urinalysis. An increased amount of urine diacylglycerol was significantly associated with clumping of echoes (P = 0.02) and the amount of lipid droplets seen on urinalysis (P = 0.04). An association between increased amounts of urine diacylglycerol and the amount of echoes seen on ultrasound approached significance (P = 0.05). Findings from this study support previously published theories that sonographic echoes within the urinary bladder of clinically normal cats may be due to urine lipid.     

A comparison of the antigenicity of the extracellular products and whole-cell sonicates from Mycobacterium spp. in rabbits, mice and fish by immunoblotting and enzyme-linked immunosorbent assay

The antigenicity of extracellular products (ECPs) derived from Mycobacterium spp. isolated from snakehead, Channa striata (Bloch), and Siamese fighting fish, Betta splendens (Regan), were examined by immunoblotting and enzyme-linked immunosorbent assay (ELISA) using sera collected from immunized rabbits, mice and fish (rainbow trout). All three species responded to a 65-kDa protein present in both the ECPs and whole cell sonicates (WCSs) from a variety of Mycobacterium spp. Cross-reactivity of anti- M. tuberculosis and anti-human heat-shock protein monoclonal antibodies (MAbs), and the presence of fibronectin binding proteins secreted into ECPs of mycobacteria were also examined. The MAbs against human 60-kDa heat-shock protein cross- reacted with the band at 65 kDa in the ECPs of TB1 (isolated from snakehead fish) and the type strain M. marinum, while the anti- M. tuberculosis MAb F29–47 elicited a strong reaction with a band at 21 kDa with most of the ECPs from mycobacterial strains examined. The major fibronectin-binding proteins were located between 21 and 25 kDa. The 65-kDa protein from ECPs of Mycobacterium spp. proved strongly immunogenic to rabbits, mice and fish. Rabbit antiserum against the 65-kDa protein from strain TB267 reacted with many non- Mycobacterium WCSs, and therefore, the 65-kDa protein from Mycobacterium spp. is believed to be a common protein found in many fish bacterial pathogens.     

Opto-electronic counters for postlarvae and juveniles of Machrobrachium rosenbergii (de Man); design and tests of Type A counter

Postlarvae or juveniles of Macrobrachium rosenbergii produced in Mauritius are sold at unit price to prawn farmers and are counted individually by hand. This process is time consuming, labour intensive, subject to error and may stress the juveniles; safe rapid electronic counting would be highly advantageous.The design of the hydraulic component of a successful counter prototype, Type A, is described. The counter has 10 parallel channels through which juveniles are carried in a water current. The detection of juveniles passing through these channels can be done photo-electrically. The counter accepts juveniles up to 15 mm in length (eye orbit to tip telson) and has the significant advantage that it can be constructed using only simple hand tools.Survival and growth rate tests, and microscopic examination for damage to appendages of juveniles were done on machine counted and hand counted juveniles. There was no reduction of growth or survival caused by passage through the counter by comparison with the hand counting method, and it is concluded that the counter is not detrimental to juvenile prawns.About 70% of all juveniles tested showed highly variable amounts of damage. The great majority of this damage appears to originate in the hatchery tanks, prior to the experimental treatments. Only in the case of antennules could the use of the counter be shown to increase damage significantly, i.e. from 25% to 38%, but this has no detectable effect on subsequent survival or growth.This appears to be the first counter made specifically for counting macroscopic crustacean juveniles, and via suitable scaling, adaptation to counting other species of crustaceans, fish larvae, etc., should be possible.     

Intake and discharge nutrient loads at three intensive shrimp farms

This study was conducted to help provide a framework for Australian regulation of shrimp farm siting and discharges. Monitoring of farm water usage, and intake and discharge water quality was conducted at three commercial intensive shrimp farms, chosen to represent different operating environments, latitudes, cultured species and management styles. Weekly samples were taken over 3 years, for 3–12 months at each farm, to investigate intake and discharge concentrations and loads of total suspended solids (TSS), total nitrogen (TN) and total phosphorus (TP). Mean water exchange was 1.4 ML ha^?1 day^?1 (about 10% day^?1) at the first farm studied and 0.5 ML ha^?1 day^?1 (about 3.6% day^?1) at the others. Farm mean discharge concentration varied as follows: TSS, from 36.9 to 119 mg L^?1; TN, from 2.1 to 3.1 mg L^?1 and TP, from 0.22 to 0.28 mg L^?1. Farm mean intake concentrations were from 11% to 91% of equivalent mean discharge concentration (for TN at Farm B and TSS at Farm C respectively). Mean net discharge loads, related to area of production ponds at each farm, varied as follows: TSS, from 4.8 to 85.7 kg ha^?1 day^?1; TN, from 1 to 1.8 kg ha^?1 day^?1 and TP, from 0.11 to 0.22 kg ha^?1 day^?1. The highest net loads of TSS, TN and TP were all from the farm with the highest water exchange rate, located on a coastal river, and studied during a year of high rainfall with associated poor water quality. These results can be used to help predict likely discharge characteristics for new shrimp farms, and provide a benchmark against which to evaluate future improvements in shrimp farm environmental management.     

Use of surface plasmon resonance (SPR) to study the dissociation and polysaccharide binding of casein micelles and caseins

Tests were made to determine whether surface plasmon resonance (SPR) could be used as a technique to study the dissociation properties of bovine casein micelles or of sodium caseinate and the interactions between these protein particles and different polysaccharides. Surfaces of bound micelles or caseinate were made, and the changes in refractive index of these layers were used to define changes in the structures of the chemisorbed material. The technique appears to have some potential for studying details of the dissociation of casein micelles and of the binding of different polysaccharides to caseins.     

Cartilage proteoglycans from normal and osteochondrotic porcine joints.

Modern pigs grow fast but are highly susceptible to degenerative joint abnormalities, including osteochondrosis. Normal and osteochondrotic humeri and femurs were obtained from five normal and ten lame adolescent boars to study cartilage proteoglycans. Histological examination of joints indicated a locally-reduced intensity of proteoglycan staining by safranin-O in lesion areas of cartilage. Cartilage proteoglycans extracted with 4.0 M guanidinium chloride were studied using Sepharose 2B gel chromatography. The proteoglycans from severely osteochondrotic joints were less (P less than 0.05) aggregated and contained a greater (P less than 0.05) proportion of smaller monomers than those from normal joints. Loss or damage of core protein, including its hyaluronic acid-binding regions, may account for the greater proportion of small monomers. The results also indicated that the proportion of hyaluronic acid in the total glycosaminoglycan uronic acid fraction, estimated by Sephadex G-200 chromatography and cellulose acetate electrophoresis, was lower (P less than 0.05) for the extracted proteoglycans than for the residual or the whole cartilage proteoglycans in all joints studied.