Effect on canine oral health of adding chlorhexidine to a dental hygiene chew

A study to compare the effect of a dental hygiene chew with or without 0.2% chlorhexidine on the development of gingivitis and the accumulation of dental deposits was performed using 11 small dogs. Confirming previous data, the daily addition of a standard chew to a dry diet resulted in significantly less gingivitis and calculus after 3 weeks compared with feeding the dry diet alone. Addition of chlorhexidine to the chew made no difference to the degree of gingivitis or the amount of calculus that accumulated, but did result in significantly less plaque accumulation after 3 weeks. The abrasiveness of the chew, rather than the antibacterial activity of chlorhexidine, is likely to have contributed the most to the maintenance of oral health in dogs with mild gingivitis.     

Effect of natural zeolite on yolk: Albumen ratio in hen eggs

1. The egg yolk: albumen (Y:A) ratio during the laying year was investigated in a commercial strain (Hisex) when natural zeolite was added to a layer's diet. 2. Dietary natural zeolite (NZ) increased both egg weight and albumen weight, while yolk weight was not significantly affected. 3. The Y:A ratio was less (more albumen) in eggs laid by hens on zeolite treatments. It was concluded that by feeding NZ it is possible to alter the Y:A ratio.     

Influence of high dietary vitamin E supplementation on egg production and plasma characteristics in hens subjected to heat stress

1. The effects of different dietary concentrations of vitamin E (alpha-tocopherol acetate) were investigated in 2 experiments on laying hens exposed to chronic heat stress at 32C. 2. In the first experiment, egg production and plasma concentrations of calcium and egg yolk precursors were measured in 24 hens before, during and after a stress period of one week and fed on diets containing 10 or 500 mg vitamin E/kg. 3. In the second, larger experiment, egg production and food intake were measured in 300 hens housed in 2 temperature-controlled rooms and fed on diets containing 10, 125 or 500 mg vitamin E/kg. Birds in room 1 were stressed from 24 to 28 weeks of age and those in room 2 from 32 to 36 weeks. 4. In experiment 1, egg production and egg weight were significantly higher (72.6 vs 51.2%, P < 0.05 and 66.6 vs 63.1 g, P < 0.005 respectively) during and after the period of stress in the group given 500 mg vitamin E/kg. Plasma concentrations of calcium, vitellogenin (zinc) and VLDL (triglyceride) were also higher in this group. 5. In experiment 2, egg production was significantly higher (65.4 vs 56.2%, P < 0.05) during and after the period of heat stress in birds in room 1 fed on the diet containing 500 mg vitamin E/kg. Egg production was also higher (49.9% vs 44.7%) on this treatment during the stress period in room 2, though the difference was not significant (P < 0.10). Egg weight and food intake were unaffected by treatment in either room. 6. It is concluded that dietary supplementation with extra vitamin E can, at least in part, alleviate the adverse effects of chronic heat stress in laying hens, perhaps by maintaining the supply of egg precursors in plasma.     

Oxidative responses in ferret macrophages

Although the basic function of T and B lymphocytes in ferrets has been known for some time, the function of mononuclear phagocytes has not been described in this species. The present study has characterised basic oxidative responses in ferret macrophages, and has investigated the effects of endogenous and exogenous modulators of macrophage function on oxidative capacity in vitro. Macrophages derived from the blood or lungs of ferrets were shown capable of generating the reactive oxygen intermediate (ROI) molecules superoxide and hydrogen peroxide, and secreting a lysosomal enzyme (acid phosphatase), in response to appropriate stimuli. A T cell supernatant (derived from mitogen-stimulated peripheral blood lymphocytes) was able to activate both blood- and lung-derived macrophages for enhanced ROI production, while specific ROI inhibitors (superoxide dismutase and catalase) were able to partially ablate ROI activity. The accumulation of nitrite in culture supernatants, as an indicator for the production of reactive nitrogen intermediates, could not be demonstrated by ferret macrophages derived from either tissue source. In contrast to the enhancing effects of TCS on the oxidative function of blood-derived macrophages, exposure to bacterial LPS caused marked suppression of ROI and lysosomal enzyme production by these cells. Finally, the generation of superoxide anion, following phagocytosis of live or heat-killed Mycobacterium bovis or zymosan, indicated that ROI production in response to phagocytic stimulation was relatively weak in ferret blood-derived macrophages. These results are discussed in relation to the study of immune function in a novel species, and with particular reference to research into tuberculosis (Tb), since ferrets are important wildlife vectors of bovine Tb in New Zealand.     

Analysis of first gastric compartment fluid collected via percutaneous paracentesis from healthy llamas

OBJECTIVE: To evaluate the safety and efficacy of percutaneous paracentesis for fluid collection from the first gastric compartment of healthy llamas and to describe characteristics of that fluid. DESIGN: Prospective study. ANIMALS: 10 healthy adult llamas. PROCEDURE: Physical examinations were performed prior to sample collection and for 14 days afterwards. A CBC was performed prior to sample collection and 5 days later. A 16-gauge, 7.5-cm stainless steel needle, positioned approximately 20 cm caudal to the costochondral junction of the last rib, was pointed in a dorsocraniomedial direction and pushed through the abdominal wall into the lumen of the first gastric compartment. Fluid was aspirated and analyzed immediately for color, odor, consistency, pH, methylene blue reduction (MBR) time, protozoa, and bacteria. RESULTS: Fluid samples were obtained from 9 of 10 llamas. Mean volume was 4.1 ml, mean pH was 6.67, and mean MBR time was 173 seconds. Odor was slightly acidic, color was light brown-green to light yellow-green, and consistency was moderate. Small protozoa with variable iodine staining and gram-negative bacteria were commonly detected. With few exceptions, results of physical examinations and CBC remained within reference ranges. CLINICAL IMPLICATIONS: Fluid samples from the first gastric compartment can be successfully obtained by percutaneous paracentesis. Fluid characteristics were similar to those of fluid collected via orogastric tube in llamas and cattle.     

Influence of the number of days spent training in an abattoir with access to live cows on the efficiency of do-it-yourself artificial insemination

Data relating to 35,389 inseminations carried out in the first three years after inseminators were trained were collected by postal questionnaire from 94 do-it-yourself (DIY) artificial inseminators in the UK. The mean calving rate from 14,528 inseminations they carried out on 92 farms in the first year after they were trained was 59.4 per cent (range 5 to 92 per cent). In the second year the mean calving rate from 11,515 inseminations by 64 inseminators was 62.3 per cent (range 33 to 88 per cent), and in the third year the mean calving rate from 9346 inseminations by 49 inseminators was 64.6 per cent (range 41 to 92 per cent). There was an increase of 5.2 per cent in the mean calving rate over the three years with an overall mean calving rate of 61.5 per cent. Each trainee carried out an average of 376 inseminations (range 20 to 800) during the three years. Thirteen instructors were responsible for the tuition and the average time the trainees spent in an abattoir with access to live cows was 2.88 days, with a range from none to five days. For the trainees who spent up to three days training in an abattoir there was an increase of 5.9 per cent in the calving rate they achieved in their first year for every day they spent training with access to live cows (P < 0.005), but there were no significant effects on the outcome of their inseminations in their second or third years.     

Metabolic changes concerning the effect of castration on some blood constituents in male rabbits

This experiment was conducted to determine the effects of castration on some metabolic alterations concerning proteins, lipids and minerals metabolism in both immature and mature rabbits. Twenty male New Zealand White rabbits (10 immature and 10 mature) were used. Blood samples were collected from the immature and mature intact animals (control non castrated). Moreover, the castrated animal groups (immature and mature) were sampled at 2, 4, 6 and 8 weeks after castration. The obtained results revealed that, castration caused a significant decrease in serum total protein, albumin, alpha 1-globulins and alpha 2-globulins concentrations. Meanwhile, gamma-globulins level was decreased temporarily at 2 weeks after castration in mature rabbits. beta-globulins level revealed non significant decrease at 2 weeks after castration in immature rabbits followed by a non significant increase. In mature rabbits beta-globulins level non significantly increased. A significant decrease in serum total nucleic acid concentrations was observed after castration throughout the experimental periods, whereas the value of serum uric acid level markedly increased after castration. Serum lipids concentrations (total lipids, total cholesterol, phospholipids and non esterified fatty acids) were increased after castration. The value of serum trace elements including copper, iron, zinc and manganese concentrations showed a significant decrease after castration. The decrease in serum copper and zinc levels were markedly observed in mature castrated rabbits. Also, serum sodium and potassium concentrations were decreased after castration. Testosterone propionate administration in mature castrated rabbits restored most of the investigated serum blood parameters to the levels of intact non castrated mature rabbit. It could be concluded that castration (deficiency of testosterone) induced marked decrease in protein synthesis and increased protein degradation, but serum lipids markedly elevated after castration in both immature and mature animals. Also, castration caused a marked decrease in some serum minerals and trace elements.     

Evaluation of the white-coat effect in cats

The diagnosis and management of systemic hypertension in cats requires a reliable method for measurement of systemic arterial blood pressure (BP) in clinical patients. Unfortunately, the setting of a clinical practice and the act of measuring BP might raise BP and heart rate (HR), an effect referred to as the white-coat effect in human patients. The purpose of the present study was to determine if a white-coat effect was experienced by cats. Radiotelemetric implants were used to measure BP and HR in 13 conscious cats in a research colony while undisturbed in their cages and while subjected to simulated visits to a veterinarian's office. The white-coat effect was taken to be the difference between the overall 24-hour average value for parameters of BP and HR and the corresponding value during the simulated office visit. A white-coat effect was observed in cats. In healthy cats, the systolic BP measured during the examination period of the simulated office visit exceeded the 24-hour average systolic BP by 17.6+/-1.5 mm Hg. However, marked heterogeneity occurred in the pattern and magnitude of the increase in systolic BP above the 24-hour baseline and the increase varied between 75.3 and -27.2 mm Hg for the healthy cats. Variation in response to the simulated office visit was observed among cats and among visits by the same cat. During an office visit, the magnitude of the white-coat effect tended to decrease, but not disappear, over time. The magnitude of the white-coat effect varied when cats were subjected to 5 repeat office visits, but did not diminish in the group as a whole. The mean increase in systolic BP during the examination (22.3+/-0.9 mm Hg) was greater (P < .05) in cats with renal insufficiency. Although the heterogeneity of response expected from companion animals might be greater than that observed in these colony cats, these results indicate that veterinarians should carefully consider the white-coat effect in evaluation of BP in cats. A quiet, undisturbed environment and adequate time for acclimation should be included in the standard protocol for measurements of BP. Because of day-to-day variation in the white-coat effect in individual cats, multiple serial measurements following a standard protocol should provide the best estimate of BP in cats.     

Model field study of Sumithion 50 EC and Fusilade S on pheasants.

Toxicological studies on wild animals play an important role in the ecotoxicological examination of pesticides. The applied model tests enable the assessment of toxicological consequences with particular regard to the life and nutrition of wild animals in the ploughed field among plants treated with pesticides. The application of different pesticide formulations on plough-land may pose a simultaneous chemical burden to wild birds. In this model study, manifestations of the interaction between an insecticide and a herbicide were studied in pheasants. The birds were placed on lucerne in cages (48 m2) and sprayed once. The applied doses were: Sumithion 50 EC 1 litre/ha + Fusilade S 6 litres/ha (practical doses) and Sumithion 50 EC 5 litres/ha + Fusilade S 30 litres/ha. The analytically determined pesticide concentration of the lucerne was taken as a basis in the further treatment of fodder. The fodder of pheasants contained the following chemicals: 85 mg/kg Sumithion 50 EC + 510 mg/kg Fusilade S and 425 mg/kg Sumithion 50 EC + 2250 mg/kg Fusilade S. Sporadic deaths observed among the pheasants were of traumatic origin and not due to a toxic effect. The decrease of body weight was significant only at the higher dose levels. Acetylcholinesterase (AChE) activity of the blood decreased significantly in both dose groups. On the basis of the results obtained it can be established that at the dose level used in the practice the pesticides studied do not give rise to a toxic interaction in pheasants.