Computed Tomographic Angiography of the Pancreas in Cats with Chronic Diabetes Mellitus Compared to Normal Cats

Background

Diabetes mellitus (DM) is a common endocrinopathy in cats. No known diagnostic test or patient characteristic at the time of diagnosis can predict likely disease course, unlike in people in whom computed tomographic angiography (CTA) is used. No published data exist regarding the CTA appearance of the pancreas in cats with DM, and thus, it is unknown what if any CTA variables should be further assessed for associations with pancreatic endocrine function.

Hypothesis/Objectives

A significant difference in pancreatic attenuation, volume, and size will be identified between normal cats and those with chronic DM on CTA.

Animals

Ten healthy control cats and 15 cats with naturally occurring DM present for >12 months.

Methods

Prospective cross‐sectional study comparing pancreatic attenuation, enhancement pattern, size, volume, pancreatic volume‐to‐body weight ratio (V:BW), pancreatic arterial: portal phase ratio (A:P), time‐to‐arterial enhancement, and time‐to‐peak portal enhancement on CTA between sedated healthy control cats and those with chronic DM.

Results

The pancreas in cats with chronic DM was significantly larger, had higher volume, higher V:BW, and shorter time‐to‐peak portal enhancement on CTA when compared to normal cats.

Conclusions and Clinical Importance

Peak portal enhancement time, pancreatic size, pancreatic volume, and V:BW can be used to differentiate normal sedated cats from those with chronic DM by CTA. These variables warrant further investigation to identify possible associations with endocrine function.     

The evolution and application of enzymes in the animal feed industry: the role of data interpretation

ABSTRACT

1. Enzymes have been used commercially for nearly 40 years and save significant costs through sparing of expensive nutrients but the mechanism by which this is achieved is still debated.

2. The research focused on non-starch polysaccharidase (NSPase) enzymes is used as an example of where greater progress could have been made if the details of the work had been described more fully and the analysis of the data generated had been broader in scope and more critical.

3. Lack of standardisation of the details presented in the materials and methods has been identified as a significant barrier to meaningful retrospective analysis and thus limits advances in the understanding of the mode of action of these enzymes.

4. The identity of the enzyme employed and its activity is often lacking, and more importantly the purity is rarely disclosed. Contaminant activities which are neither listed nor assayed could play a significant role in the responses observed.

5. The dose optimum of most enzymes is often considerably higher than that employed in most studies. Thus studies claiming synergy between two ‘activities’ should ensure that the response is not related to each enzyme simply augmenting the dose of just one activity in the finished feed. This is a common problem, and coupled with the lack of factorial experiments to justify the presence of each enzyme in a multi-enzyme product, it is not surprising that there is still debate as to whether single or multi-enzymes are best suited poultry rations.

6. The three proposed mechanisms for NSPases (viscosity, cell wall and prebiotic) are discussed, and along with their strengths and weaknesses it is suggested that a re-evaluation of each is needed. Viscosity may have to be re-evaluated as being a function not only of the cereal being fed, but of the age of the animal as well. The cell wall theory as described is poorly modelled in vitro and hence the validity of these data is questioned. The prebiotic theory may need significant modification as it appears that the quantities of oligomers produced are insufficient to generate the additional volatile fatty acids (VFA)’s reported. It is likely that all three mechanisms play a role in the responses observed, but the prebiotic mechanism probably plays by far the most important part in low viscosity diets.

7. Future research would be improved if it considered all potential mechanisms when designing a trial. Significant failings are apparent as a result of adherence to tenets in explanation of the results. Most importantly, it should be emphasised that a hypothesis is there to be tested, not defended.