A COMPARISON OF FLUORIMETRIC AND COLORIMETRIC METHODS FOR THE DETERMINATION OF α-MANNOSIDASE ACTIVITY IN BOVINE PLASMA

This paper compares both manual colorimetric and fluorimetric methods for the assay of acidic alpha-mannosidase activity in bovine EDTA plasma. The effect of variable blood volumes per 10 ml blood collecting tube has been investigated, and the colorimetric assay conditions adjusted (for example, zinc concentration in pre-incubation buffer) to cope with low blood volumes resulting in high EDTA/plasma ratios. We have shown that with non-haemolysed EDTA plasma samples, the two methods give similar results, but for haemolysed samples, the colorimetric method yields significantly lower results than those obtained fluorimetrically. Using the manual fluorimetric method, samples can be assayed more rapidly and simply than by using the colorimetric method. This provides definite advantages in a laboratory receiving variable numbers of samples, or which cannot afford the high cost of automated equipment.     

Production and characterization of monoclonal antibodies to cervine herpesvirus-1.

Fourteen hybridoma cell lines secreting monoclonal antibodies (Mab) to cervine herpesvirus-1 (CerHV-1) produced following the fusion of NSO myeloma cells with splenocytes of BALB/c mice previously immunized with gradient purified CerHV-1 were selected using an indirect enzyme-linked immunosorbent assay (ELISA) employing CerHV-1 antigen and tested by the ELISA against four other ruminant alphaherpesviruses from cattle (bovine herpesvirus type 1.1 and 1.2) goat (caprine herpesvirus-2) and reindeer (rangiferine herpesvirus-1). Comparison of all five ruminant alphaherpesviruses with these Mabs confirmed their close antigenic relationships, with two Mabs reacting against all viruses. Ten Mabs which were able to differentiate between the viruses reacted with a 64 kDa polypeptide in a western blot. Four Mabs including two specific only for CerHV-1 with neutralizing activity against the virus used for immunization were directed against a 74 kDa viral protein.     

Evaluation of laparoscopic-assisted placement of jejunostomy feeding tubes in dogs

OBJECTIVE: To evaluate feasibility of performing laparoscopic-assisted placement of a jejunostomy feeding tube (J-tube) and compare complications associated with placement, short-term feedings, and medium-term healing with surgically placed tubes in dogs. DESIGN: Prospective study. ANIMALS: 15 healthy mixed-breed dogs. PROCEDURES: Dogs were randomly allocated to undergo open surgical or laparoscopic-assisted J-tube placement. Required nutrients were administered by a combination of enteric and oral feeding while monitoring for complications. Radiographic contrast studies documented tube direction and location, altered motility, or evidence of stricture. RESULTS: Jejunostomy tubes were successfully placed in the correct location and direction in all dogs. In the laparoscopic group, the ileum was initially selected in 2 dogs, 2 dogs developed moderate hemorrhage at a portal site, and 2 J-tubes kinked during placement but were successfully readjusted postoperatively. All dogs tolerated postoperative feedings. All dogs developed minor ostomy site inflammation, and 1 dog developed bile-induced dermatitis at the ostomy site. Despite mild, transient neutrophilia, no significant difference was noted in WBC counts between groups. No dog had altered gastric motility or evidence of stricture, although the jejunopexy site remained identifiable in several dogs at 30 days. CONCLUSIONS AND CLINICAL RELEVANCE: Requirements for successful J-tube placement were met by use of a laparoscopic-assisted technique, and postoperative complications were mild and comparable to those seen with surgical placement. Laparoscopic-assisted J-tube placement compares favorably to surgical placement in healthy dogs and should be considered as an option for dogs requiring enterostomy feeding but not requiring a celiotomy for other reasons.     

Manipulation of the n-3 polyunsaturated fatty acid content of muscle and adipose tissue in lambs

Fifty Suffolk-crossbred wether lambs, with an initial live weight of 29 +/- 2.1 kg, were allocated to one of five concentrate-based diets formulated to have a similar fatty acid content (60 g/kg DM), but containing either linseed oil (high in 18:3n-3); fish oil (high in 20:5n-3 and 22:6n-3); protected linseed and soybean (PLS; high in 18:2n-6 and 18:3n-3); fish oil and marine algae (fish/algae; high in 20:5n-3 and 22:6n-3); or PLS and algae (PLS/algae; high in 18:3n-3 and 22:6n-3). Lambs were slaughtered when they reached 40 kg. Growth performance and intake were similar (P > 0.35) among treatments. By contrast, gain:feed was higher (P < 0.05) in lambs fed the fish oil compared with the linseed oil or PLS/algae diets. Total fatty acid concentration (mg/100 g) in the neutral lipid of the longissimus muscle was not affected by treatment (P > 0.87) but was least (P < 0.05) in the phospholipid fraction in lambs fed the linseed oil diet. Lambs fed either diet containing marine algae contained the highest (P < 0.05) percentage of 22:6n-3 in the phospholipid (mean of 5.2%), 2.8-fold higher than in sheep fed the fish oil diet. In lambs fed the fish/algae diet, the percentage of 20:5n-3 was highest (P < 0.05), contributing some 8.7, 0.8, and 0.5% of the total fatty acids in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The percentage of 18:3n-3 in the phospholipid fraction of the LM was highest (P < 0.05) in lambs fed the linseed oil diet (6.9%), a value double that of sheep fed the PLS diet. By contrast, lambs fed the PLS diet had twice the percentage of 18:3n-3 in the muscle neutral lipids (3.8%) than those offered the linseed oil diet, and 5.5-fold greater than lambs fed the fish/algae treatment (P < 0.05), an effect that was similar in the adipose tissue. The percentage of 18:2n-6 was highest (P < 0.05) in lambs fed the PLS diet, where it contributed 33.7, 10.1, and 11.2% in the muscle phospholipid, neutral lipids, and adipose tissue, respectively. The highest (P < 0.05) muscle PUFA-to-saturated fatty acid (P:S) ratio was obtained in lambs fed the PLS diet (0.57), followed by the PLS/algae diet (0.46), and those fed the fish oil or linseed oil diets had the lowest ratios (0.19 and 0.26, respectively). The favorable P:S ratio of lambs fed the PLS/algae diet, in conjunction with the increased levels of 20:5n-3 and 22:6n-3, enhanced the nutritional qualities of lamb to more closely resemble what is recommended for the human diet.