J. S. Rand

Acute Stress Hyperglycemia in Cats Is Associated with Struggling and Increased Concentrations of Lactate and Norepinephrine

We characterized the changes in blood glucose concentrations in healthy cats exposed to a short stressor and determined the associations between glucose concentrations, behavioral indicators of stress, and blood variables implicated in stress hyperglycemia (plasma glucose, lactate, insulin, glucagon, cortisol, epinephrine, and norepinephrine concentrations). Twenty healthy adult cats with normal glucose tolerance had a 5-minute spray bath. Struggling and vocalization were the most frequent behavioral responses. There was a strong relationship between struggling and concentrations of glucose and lactate. Glucose and lactate concentrations increased rapidly and significantly in all cats in response to bathing, with peak concentrations occurring at the end of the bath (glucose baseline 83 mg/dL, mean peak 162 mg/dL; lactate baseline 6.3 mg/dL, mean peak 64.0 mg/dL). Glucose response resolved within 90 minutes in 12 of the 20 cats. Changes in mean glucose concentrations were strongly correlated with changes in mean lactate (r = .84; P < .001) and mean norepinephrine concentrations (r = .81; P < .001). There was no significant correlation between changes in mean glucose concentrations and changes in mean insulin, glucagon, cortisol, or epinephrine concentrations. Struggling and lactate concentrations were predictive of hyperglycemia. Gluconeogenesis stimulated by lactate release is the likely mechanism for hyperglycemia in healthy cats in this model of acute stress. Careful handling techniques that minimize struggling associated with blood collection may reduce the incidence of stress hyperglycemia in cats.

Insulin sensitivity decreases with obesity, and lean cats with low insulin sensitivity are at greatest risk of glucose intolerance with weight gain

This study quantifies the effects of marked weight gain on glucose and insulin metabolism in 16 cats which increased their weight by an average of 44.2% over 10 months. Significantly, the development of feline obesity was accompanied by a 52% decrease in tissue sensitivity to insulin and diminished glucose effectiveness. In addition, glucose intolerance and abnormal insulin response occurred in some cats. An important finding was that normal weight cats with low insulin sensitivity and glucose effectiveness were at increased risk of developing impaired glucose tolerance with obesity. High basal insulin concentrations or low acute insulin response to glucose also independently increased the risk for developing impaired glucose tolerance. Male cats gained more weight relative to females and this, combined with their tendency to lower insulin sensitivity and higher insulin concentrations, may explain why male cats are at greater risk for diabetes. Results suggest an underlying predisposition for glucose intolerance in some cats, which is exacerbated by obesity. These cats may be more at risk of progressing to overt type 2 diabetes mellitus.

Behavioural observations of piglets undergoing tail docking, teeth clipping and ear notching

Abstract The behaviour of 279 newborn Large White × Landrace hybrid piglets in a Specific Pathogen Free Piggery (University of Queensland, Australia) was recorded during and after routine management practices of tail docking, ear notching and teeth clipping. The behaviours were recorded at the time of the procedure and then at 30 s intervals for 2 min after completion of the procedure. Piglets that received one or all of the procedures behaved differently ( P P The behaviours observed were often correlated with a particular procedure: tail docking caused more tail jamming and wagging; head shaking occurred most with ear notching; teeth clipping caused more teeth champing. Grunting during and in the first 60 s after the procedure was most frequent for piglets that had their tails docked. There was a high degree of individual variation within each litter for piglets undergoing the same procedure. The frequency of behaviours was greatest immediately after the procedure. The statistical differences evident in the period 0–30 s decreased over time and eventually disappeared after approximately 2 min. Restraint of the piglet appeared to be stressful in itself. However, restraint combined with a procedure resulted in an alteration of the behaviour from the basal levels shown by piglets that were only handled. This change in behaviour could indicate that routine management procedures (although transient) are stressful to the piglet and warrant investigation into ways to alleviate this distress.

Dog‐assisted therapy for older people with dementia: A review

This review summarises and critiques the published literature regarding dog therapy for older people with dementia living in residential aged care facilities. Nine studies were identified for inclusion and although the methodological variability of studies makes it difficult to draw firm conclusions, research suggests that dog therapy is beneficial for people with dementia. The most frequently reported findings were an increase in social behaviour and a decrease in agitated behaviour during dog contact. Improvement in social behaviour was found to be unrelated to the severity of dementia. Various improvements on measures of global function were also reported. No study adopted a randomised controlled trial design and a number of potentially important factors were not controlled for, including halo effects of animals on caregivers that may bias caregivers’ responses when acting as proxies for their relatives or residents. The premorbid relationship with dogs may be an important variable influencing outcomes.

Plasma leptin concentrations in cats: Reference range, effect of weight gain and relationship with adiposity as measured by dual energy x-ray absorptiometry

The aims of our study were to determine a reference range for plasma leptin in healthy, normal-weight cats and to measure the effect of weight gain on plasma leptin levels. To increase our understanding of the association between leptin and feline obesity, we investigated the relationship between plasma leptin and measures of adiposity in cats. Twenty-six normal-weight cats were used to determine the reference range for feline leptin using a multispecies radioimmunoassay. In the second part of the study, plasma leptin concentrations were determined in 16 cats before and after approximately 10 months of spontaneous weight gain. Dual energy X-ray absorptiometry scans (DEXA) were performed after weight gain. The tolerance interval for plasma leptin concentrations was 0.92–11.9 ng/ml Human Equivalent (HE) with a mean concentration of 6.41 ± 2.19 ng/ml HE. In part two of the study, 16 cats gained on average 44.2% bodyweight over 10 months. The percentage of body fat in obese cats ranged from 34.2 to 48.7%. Mean plasma leptin concentrations increased from 7.88 ± 4.02 ng/ml HE before weight gain to 24.5 ± 12.1 ng/ml HE after weight gain, (P < 0.001). Total body fat and body fat per cent were the strongest predictors of plasma leptin in obese cats (r = 0.8 and r = 0.78, P < 0.001, respectively). In conclusion, plasma leptin concentrations increased three-fold in cats as a result of weight gain and were strongly correlated with the amount of adipose tissue present. Despite elevated leptin levels, cats continued to eat and gain weight, suggesting decreased sensitivity to leptin. This investigation into the biology of leptin in cats may aid the overall understanding of the role of leptin and the development of future treatments to help prevent and manage feline obesity.

Basal plasma insulin and homeostasis model assessment (HOMA) are indicators of insulin sensitivity in cats

The objective of this study was to compare simpler indices of insulin sensitivity with the minimal model-derived insulin sensitivity index to identify a simple and reliable alternative method for assessing insulin sensitivity in cats. In addition, we aimed to determine whether this simpler measure or measures showed consistency of association across differing body weights and glucose tolerance levels. Data from glucose tolerance and insulin sensitivity tests performed in 32 cats with varying body weights (underweight to obese), including seven cats with impaired glucose tolerance, were used to assess the relationship between Bergmans minimal model-derived insulin sensitivity index (SI), and various simpler measures of insulin sensitivity. The most useful overall predictors of insulin sensitivity were basal plasma insulin concentrations and the homeostasis model assessment (HOMA), which is the product of basal glucose and insulin concentrations divided by 22.5. It is concluded that measurement of plasma insulin concentrations in cats with food withheld for 24 h, in conjunction with HOMA, could be used in clinical research projects and by practicing veterinarians to screen for reduced insulin sensitivity in cats. Such cats may be at increased risk of developing impaired glucose tolerance and type 2 diabetes mellitus. Early detection of these cats would enable preventative intervention programs such as weight reduction, increased physical activity and dietary modifications to be instigated.

Intensive blood glucose control is safe and effective in diabetic cats using home monitoring and treatment with glargine

Human diabetic patients routinely self-adjust their insulin dose using a protocol and home monitoring, and perform equally well or outperform physician directed adjustments. The objective of this study was to report the outcome of home monitoring of diabetic cats by owners using a protocol aimed at achieving euglycaemia, using ultra-low carbohydrate diets (≤10% metabolisable energy) and the insulin analogue glargine for >10 weeks and/or until remission was achieved. Fifty-five cats diagnosed with diabetes mellitus, whose owners joined the online German Diabetes-Katzen Forum, were included. An overall remission rate of 64% was achieved in the cohort. Significantly higher remission rates were observed if good glycaemic control was achieved soon after diagnosis: 84% for cats started on the protocol within 6 months of diagnosis went into remission, and only 35% for cats that began more than 6 months after diagnosis (P<0.001). Only one mild clinical hypoglycaemic episode occurred observed despite tight blood glucose control. In conclusion, intensive blood glucose control is safe and effective in diabetic cats using home monitoring and treatment with glargine.

Treatment of newly diagnosed diabetic cats with glargine insulin improves glycaemic control and results in higher probability of remission than protamine zinc and lente insulins.

Glycaemic control and remission probabilities were compared in 24 newly diagnosed diabetic cats treated twice daily with either glargine, protamine zinc (PZI) or lente insulin and fed a low carbohydrate diet. After day 17, the probability of remission was substantially higher for cats with lower mean 12 h blood glucose concentrations on day 17, irrespective of insulin type. Glargine-treated cats had lower mean 12 h blood glucose concentrations on day 17 than PZI- or lente-treated cats, and all eight glargine-treated cats achieved remission compared to three PZI- and two lente-treated cats. The probability of remission was greater for cats treated with glargine than cats treated with PZI or lente insulin. In newly diagnosed diabetic cats, twice daily treatment with glargine provides better glycaemic control and higher probability of remission compared to twice daily treatment with PZI or lente insulin. Good glycaemic control soon after diagnosis is associated with increased probability of remission and should be the goal of insulin therapy.

Plasma leptin concentrations are independently associated with insulin sensitivity in lean and overweight cats

This study investigated relationships between plasma leptin, insulin concentrations, insulin sensitivity and glucose tolerance in lean and overweight cats. Leptin concentrations were measured in 16 cats during glucose tolerance tests before and after gaining weight, and after feeding a test meal in overweight cats. An important finding of this study is that in both lean (r=-0.79) and overweight (r=-0.89) cats, the higher the leptin concentrations, the more insulin resistant the cat, independent of the degree of adiposity. Leptin concentrations at baseline and after consuming a meal tended to be higher in overweight cats with glucose intolerance, compared to overweight cats with normal glucose tolerance, although the difference was not significant. After feeding the test meal to overweight cats in the early morning, plasma leptin concentrations initially decreased before subsequently rising to peak 15 h later, which coincided with late evening. The leptin peak occurred 9 h after the insulin peak following ingestion of the test meal. Importantly, this study suggests that increased leptin concentrations may contribute to the diminished insulin sensitivity seen in overweight cats. Alternatively, the compensatory hyperinsulinaemia found with insulin resistance in overweight cats could stimulate leptin production.

Management of Canine Diabetes

The majority of diabetic dogs appear to have a form of type 1 diabetes analogous to the latent autoimmune diabetes of adults (LADA) in humans. Evidence of acute or chronic pancreatitis occurs in about 40% of diabetic dogs. Blindness caused by cataract formation eventually occurs in the majority of diabetic dogs and is not dependent on glycemic control. Insulin is the mainstay of therapy for diabetic dogs, and a conservative approach to insulin therapy is crucial. Most diabetic dogs require twice-daily dosing with lente or NPH insulin to adequately control their clinical signs. The diet fed should primarily be palatable and nutritionally balanced. Improved glycemic control may be achieved in some dogs if the diet contains increased insoluble fiber.