Exercise in electrocardiographic interpretation

The response of the heart to disease can be detected by assessing myocardial electrical activity. The electrocardiograph is a useful diagnostic tool which is widely available to the veterinary clinician. However, interpretation of the tracing often requires considerable experience.     

Comparative lipid and lipoprotein metabolism

This review summarizes a number of recent reports in several areas of lipid and lipoprotein metabolism. Absorption of dietary lipids, cholesterol synthesis, and biliary cholesterol metabolism are mentioned only briefly to be complete. Comparative aspects of lipoprotein metabolism, however, are detailed in an effort to integrate the myriad metabolic events which characterize these important lipid transport particles. Where comparative information is known, those aspects of lipoprotein metabolism that may be protective against atherogenesis in certain mammalian species are also described. Efforts to understand atherogenic resistance comparatively in animals lends a better understanding of the metabolic events leading to coronary artery disease in humans. They also provide an important basis for understanding lipid metabolism in numerous veterinary species.     

A diet formulated from by‐products and indigenous foodstuffs for laying hens

1. The performance of six commercial stocks of laying hens fed on a diet composed of home‐produced foodstuffs, not usually used for human consumption, was compared with that of birds fed on a conventional diet.

2. The experimental diet was calculated to be low in energy and methionine and high in fibre by conventional standards. Birds ate up to 12% more of this diet, but the calculated intakes of energy and methionine were less than those of the corresponding controls.

3. White stocks fed on the experimental diet produced seven eggs less per bird than controls while the production of brown stocks was essentially unaffected.

4. The gross efficiency of energy utilisation for egg production was better with the experimental diet.     

Use of Porcine Meal in Plant‐based Practical Diets for Pacific White Shrimp,Litopenaeus vannamei

Two growth trials were conducted to evaluate and confirm the efficacy of a porcine meal (PM) with high protein content (>90%) as an alternative feed ingredient in commercial‐type feed formulation for Pacific white shrimp, Litopenaeus vannamei. Six experimental diets were formulated for the two growth trials. The first five diets contained increasing levels (0, 1, 2, 4, and 6%) of PM as a replacement for soybean meal in a plant‐based diet with low inclusion level (6%) of fish meal (FM). The last experimental diet was produced utilizing 4.2% PM to completely replace FM. In Trial 1, shrimp (1.5 g initial mean weight, 20 shrimp/tank, n = 4) were offered test diets for 6 wk in a semirecirculation system. At the end of Trial 1, shrimp fed with the diet containing 6% PM exhibited significantly enhanced weight gain (WG), feed conversion ratio (FCR), and survival compared to those fed with the diet devoid of FM. As survival was poor across all treatments and different densities could mask growth results the trial was repeated. In Trial 2, shrimp (0.85 g, 15 shrimp/tank, n = 4) were offered diets for 6 wk. Dietary supplementation of PM at 6% significantly improved WG, FCR, and apparent net protein retention in contrast with the treatment devoid of FM, confirming the same trends in Trial 1. No significant difference was detected in protein, lipid, moisture, and mineral profiles of whole‐body shrimp as well as survival across all the treatments. Results of this study indicate that PM is a good high protein source in shrimp feeds, which can be included up to 6% in the low FM‐based diet without compromising the growth of shrimp.