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Objective: To evaluate the efficacy of the non‐steroidal anti‐inflammatory drug, meloxicam, in alleviating pain and inflammation and on production‐related variables in a model of sterile acute inflammation in sheep. Methods: Groups of 12 mature Merino ewes received 0, 0.5, 1.0 or 1.5 mg/kg meloxicam subcutaneously 90 min before injection of 0.1 mL turpentine subcutaneously on the anterior aspect of the proximal phalanx of a forelimb. Pain‐ and inflammation‐related variables were assessed at −18, 3, 6, 9, 12, 24, 48 and 72 h relative to meloxicam administration. Daily feed intake and body weight change 7 days later were also assessed. Pain‐related variables measured were weight borne on each forelimb, lameness score, time each forelimb was raised in a 20‐s interval and tolerance to a noxious mechanical stimulus. Inflammation‐related variables measured were skin temperature, limb circumference, body temperature, plasma haptoglobin concentration and peripheral blood leucocyte parameters. Results: Meloxicam was effective in improving all pain‐related variables. A dose‐dependent response was seen between 0 and 1.0 mg/kg, with no additional benefit provided by 1.5 mg/kg. At a dose rate of 1.0 mg/kg, meloxicam improved weight borne on the turpentine‐treated limb by 14%, reduced the time the treated limb was held in a non‐weight‐bearing posture by 46%, reduced the lameness score by 58% and improved tolerance to pressure by 52%. No significant effects of meloxicam on inflammatory variables or appetite were observed. Conclusions: Using a validated pain model, the data suggested that 1.0 mg/kg meloxicam provided significant analgesic benefits to sheep. [ABSTRACT FROM AUTHOR]

Objective To assess the effects of application of occlusive polypropylene clips to lambs on body weight, breech bare area measurements and scores, wrinkle scores, and faecal and urine stain scores. Procedures A randomised controlled trial using 32,028 lambs was conducted on 208 properties across Australia. Polypropylene clips were applied at lamb marking. At each site, 160 lambs were weighed, measured for breech bare area and scored for bare area, wrinkle, dag and urine staining, and skin type and thickness. Lambs were allocated to a control (no clips) or treatment (breech and tail clips) group. Lambs were assessed on days 14 (range 10-19) and 55 (range 34-129) after clip application for body weight, breech bare area measurements and scores. On day 55 the operators also scored wrinkling and urine staining. Results At an average of 55 days after treatment, treated ewe and wether lambs had 16% and 21% greater horizontal bare area measurements, and 31.7% and 32.7% higher bare area scores than control lambs, respectively. The ewes and wether lambs also had lower wrinkle (6.8% and 5.8%, respectively) and dag scores (12% and 12.3%, respectively) than controls. Treated ewes had lower urine stain scores (18.8%) than controls. However, body weight was slightly lower in clip-treated lambs compared with controls by 0.320 kg (1.2%) and 0.430 kg (1.6%) for ewes and wethers, respectively. Conclusion Polypropylene clips applied to the breech and tail of lambs increased breech bare area and reduced dag, urine and wrinkle scores. Improvements in these measures of factors that predispose to blowfly strike suggest that the application of clips may reduce the risk of breech flystrike. [ABSTRACT FROM AUTHOR]

Objective The objective of the study was to determine the minimum duration of clip application required to increase the size of the perineal and tail bare areas and reduce breech wrinkle, dag or urine stain scores of Merino lambs. Method The study was conducted on a single farm in western New South Wales using 491 unmulesed lambs of a plain body type (9-14 weeks of age; mean (± SD) bodyweight 26.9 ± 5.0 kg; 82% wrinkle score 1 or 2) randomly allocated into 10 groups. Groups 1-9 included 39-46 lambs treated with the clips, which were removed at 1-7, 10 or 14 days, respectively, after application. Group 10 comprised 53 lambs that were unclipped, unmulesed controls. Visual scores, bare area measurements and bodyweights were assessed before and at 28 and 60 days following clip application. Results Clips increased the size of the perineal and tail bare areas if left on the lambs for a minimum of 4-6 days. The increases in the size of the perineal and tail bare areas were similar to the results of previous studies. This indicates that the clips performed as expected, despite the current study being conducted on lambs with a plain body type. Conclusion When used as an alternative to mulesing, clips should remain on lambs for a minimum of 4-6 days to effectively increase the size of the perineal and tail bare areas. Further research is required to determine the degree of protection against flystrike provided by the clip method. [ABSTRACT FROM AUTHOR]

Objective To determine the effect of applying plastic clips to the breech and tail of lambs on the perineal and tail bare areas, breech wrinkle, dag (faecal) accumulation, urine stain, body weight and survival of lambs, compared with unclipped, unmulesed lambs and mulesed lambs. Method The study was conducted on five commercial wool-growing farms in southern Australia. On each study site lambs (2-12-weeks-old) were divided into three groups: (1) unclipped, unmulesed control (tail dock only); (2) treated with clips; and (3) treated with the mules operation. Evaluations of effects, including visual scoring, bare area measurements and body weight, were performed before treatment and on or approximately days 30, 60, 90 and 180 after treatment. On each occasion, lambs were recorded as either present or absent to allow estimates of survival. Results The clip treatment increased the size of the perineal and tail bare areas compared with the unclipped, unmulesed control lambs (P < 0.05), although the increases were less than in mulesed lambs (P < 0.05). The clips reduced breech wrinkle, dag and urine stain to levels partway between those recorded in the unclipped, unmulesed controls and the mulesed lambs (P < 0.05). Clipped lambs weighed more than mulesed lambs after treatment (days 30-90 P < 0.001; day 180 P < 0.01) and had higher cumulative percentage survival to 90 days after treatment (P = 0.03). Conclusions The clips successfully modified the breech region of lambs, although the changes were less than with mulesing. The clips did not reduce the body weight of lambs, compared with the unclipped, unmulesed control lambs, and improved 90-day cumulative percentage survival compared with mulesed lambs. [ABSTRACT FROM AUTHOR]

1. It has been proposed that phenolphthalein exerts its laxative effect via an intracellular cascade that begins with the activation of nitric oxide synthase (NOS) and ends with an inhibition of NaCl and water reabsorption from the colon. Phenolphthalein also promotes the release of potassium from cells, but it is not known how this is related to its effect on sodium and water uptake. 2. An established in vitro system was used to examine the role of nitric oxide (NO) in phenolphthalein-induced release of (86)Rb(+) from COS-7 cells. 3. Sodium nitroprusside, an NOS-independent NO source, was unable to mimic the effects of phenolphthalein and N(G)-nitro-L-arginine methyl ester, an NOS inhibitor, was unable to block the effect of phenolphthalein. 4. It is concluded that NO generation is not required for phenolphthalein-stimulated potassium release. It is proposed that the effect of phenolphthalein on cellular potassium release is mechanistically distinct from the effect on NaCl and water uptake by colonocytes.

Low concentrations of some neutral dipeptides, such as L-Ala-L-Ala, rapidly disrupt rat liver lysosomes. The phenomenon has been attributed to an osmotic imbalance generated by the production of amino acids in the lysosome by lysosomal dipeptidase activity. This hypothesis is challenged by testing several pairs of dipeptides available in both D- and L-forms and a range of dipeptides whose susceptibility to lysosomal dipeptidase activity is known. A good correlation was found between the lytic ability of dipeptides and their capacity to cross the lysosome membrane and be hydrolysed by lysosomal dipeptidase. The osmotic-imbalance hypothesis is critically evaluated in the light of the results and of recent information concerning the carrier-mediated transport of amino acids and dipeptides across the lysosome membrane. It is concluded that intralysosomal generation of amino acids remains the most plausible explanation of the lytic activity of dipeptides, and that the dipeptide porter(s) in the lysosome membrane must have higher Km than the amino acid porters.