Evaluation of Plant and Animal Source Proteins for Replacement of Fish Meal in Practical Diets for the Largemouth Bass Micropterus salmoides

Two feeding trials were conducted with juvenile largemouth bass Micropterus salmoides to evaluate alternative plant and animal source proteins for their ability to replace fish meal in practical diets. The first trial was designed to identify the most promising candidates. The second trial was conducted to evaluate how much of the fish meal could be replaced by those candidates. In Study 1, feed‐trained largemouth bass (3.1 ± 0.7 g) were randomly stocked into 18114‐L glass aquaria at 25 fish per aquarium. Fish were fed one of six experimental diets, each containing approximately 38% crude protein and 10% crude lipid, to apparent satiation twice daily. The control diet (CTL) contained 30% fish meal and 34.5% soybean meal. Diets 2–6 each contained 15% fish meal and at least 34.5% soybean meal with the remainder of the protein made up of either meat and bone meal (MBM), soybean meal (SBM), poultry by‐product meal (PBM), a 50150 mixture of blood meal and corn gluten meal (BM/CG), or 50150 mixture of hydrolyzed feather meal and soybean meal (FMISBM). There were three replicate aquaria per dietary treatment. After 12 wk, there was no significant difference (P > 0.05) among treatments in survival which averaged 92% overall. Only fish fed the PBM or BM/CG diets had average individual weights and feed conversion efficiencies that were not significantly different (P > 0.05) from the control diet (CTL). In Study 2, the formulation of the control diet (CTL) remained the same. Based on their performance in the first trial, PBM and BM/CG were chosen to now replace 75 or 100% of the fish meal. Fish were stocked at an average weight of 6.9 ± 1.7 g. After 11 wk, fish fed diets containing the BM/CG mixture at both levels were significantly smaller (P 5 0.05) than fish fed other diets and at 100% replacement survival was reduced. Fish fed diets containing poultry meal as the primary protein source performed as well as those fed the control diet (CTL). It appears that PBM can completely replace fish meal in diets for juvenile largemouth bass without adverse effects on growth, feed efficiency, or body composition.     

Caecal impaction in a dog

A seven-year-old, intact male dobermann with a four-week history of anorexia was diagnosed as having impaction of the caecum with inspissated faeces. Radiographic and histopathological findings revealed impaction of the caecum and a mild subacute locally extensive typhlitis. Typhlectomy was curative and no further problems have been reported.     

Comparative Efficacy of Anesthetics for the Freshwater Prawn Macrobrachiurn rosenbergii

Abstract— The freshwater prawn Macrobrachiurn rosenbergii is a commercially important culture species in the South Central United States. Two major constraints in the commercial culture of the freshwater prawn in the U.S. are poor survival during live transportation of seed‐stock to growout ponds, and live transportation of pond harvested prawn to distant live markets due to the territorial and cannibalistic nature of prawn. The use of anesthetics could possibly improve transport survival; however, to date anesthetic agents have not been evaluated for use with prawn. Two trials were conducted with juvenile freshwater prawn to compare the efficacy of anesthetics commonly used on fish. The first trial was designed to identify the most promising candidates. In Study 1, tricaine methanesulfonate (MS‐222), 2‐phenoxyethanol, quinaldine sulfate (quinaldine), clove oil, and Aqui‐S^TM were evaluated at 25 and 100 mg/L for 1 h in three replicate 10‐L glass containers, containing five juvenile prawn each. Relative sedation level was determined every 3 min for 1 h, then recovery time and survival were measured. In Study 1, MS‐222 and 2‐phenoxyethanol were determined to be ineffective on prawn at all rates tested. Based on their performance in Study 1, quinaldine, clove oil, and AquiS^TM were evaluated at 100, 200, and 300 mg/L in Study 2. Observations were determined as in Study 1. Clove oil and Aqui‐S^TM induced anesthesia faster and at lower concentrations than quinaldine. At the highest treatment rate (300 mg/L) prawn suffered 60% mortality in the Aqui‐S^TM treatment, 13% mortality in the quinaldine treatment, and 0% mortality in the clove oil treatment and control following a 1‐h exposure to these concentrations. Based on these data, Aqui‐S^TM and clove oil applied at 100 mg/L may be suitable anesthetic treatments for prawn. Additional research is needed to determine optimal time and dose relationships to minimize stress during holding, handling, and transportation of prawn.     

Per Rectal Portal Scintigraphy Using 99mTechnetium Pertechnetate to Diagnose Portosystemic Shunts in Dogs and Cats

Per rectal portal scintigraphy using 99mTechnetium pertechnetate (99mTcO4-) was used to diagnose portosystemic shunts (PSS) before surgical confirmation in seven dogs and two cats. Shunt fractions, representing the percent of portal blood that bypasses the liver, were determined by computer analysis of the scintigraphic images. Animals with portosystemic shunts had a mean preoperative shunt fraction of 84.02% (n = 9). The mean postoperative shunt fraction in four animals was 58.22%. The mean shunt fraction in ten control dogs was 5.00%. Per rectal portal scintigraphy is an innovative, easily performed, inexpensive method to diagnose congenital portosystemic shunts in dogs and cats.     

Effect of shock strength on survival and acute cardiac damage induced by open-thorax defibrillation of dogs

The safety of open thorax defibrillation with single damped sine-wave shocks and 6-cm-diameter electrodes was evaluated in healthy anesthetized dogs. Twenty-one dogs were allotted to 6 groups: Group A were nonshocked controls and groups B through F were given single shocks of 4-, 7-, 12-, 19-, or 32-fold, respectively, greater than a defibrillation threshold dose (30 mA/g of heart). Immediate postshock death resulted in group F dogs; group A through E dogs survived and were killed after 2 days. The incidence and severity of cardiac morphologic damage increased with shock strength (mild damage occurred in 1 of 3 dogs in group C and in 3 of 4 dogs in group D and severe damage occurred in 2 of 3 dogs in group E). The cardiac lesions were characterized grossly and microscopically. In dogs that died immediately after shocking, damage was apparent as pale circular zones of edema and myofibrillar degeneration in the ventricular free walls beneath the electrode placement sites on the cardiac surface. In the dogs that survived 2 days, the defibrillator-induced areas of myocardial necrosis and calcification were concentrated in arc or ringlike patterns beneath the periphery of the electrode placement sites. All dogs that were studied 2 days after shocking had mild fibrinous pericarditis. Postshock electrocardiographic changes were not good indicators of cardiac damage because the mild epicardial inflammatory reaction associated with the surgical procedure produced large ST and T wave changes which masked any changes associated with myocardial necrosis induced by the electric shocks. It was concluded that a substantial safety margin exists between the required defibrillation threshold shock dose and the large shocks required to produce marked cardiac damage or death in healthy dogs.     

Web-based technology: its effects on small group "problem-based learning" interactions in a professional veterinary medical program

The objective of this investigation was to ascertain whether and how the introduction of a new technology (WebCT) influenced faculty teaching styles while facilitating small group problem-based learning (PBL) sessions in a professional veterinary medical (PVM) program. The following questions guided the study: (1) How does the use of technology affect faculty teaching behaviors? (2) Do the facilitators' interactions with WebCT technology change over the course of one semester? (3) What is the perceived impact of WebCT on facilitators' role in PBL? The study employed a combination of qualitative (case study) and semi-quantitative (survey) methods to explore these issues. Nine clinical sciences faculty members, leading a total of six PBL groups, were observed over the course of an academic semester for a total of 20 instructional sessions. The qualitative data gathered by observing faculty as they facilitated PBL sessions yielded three major themes: (1) How do PBL facilitators adapt to the addition of WebCT technology? (2) Does this technology affect teaching? and (3) How do PBL facilitators interact with their students and each other over the course of a semester? No direct evidence was found to suggest that use of WebCT affected teaching behaviors (e.g., student-centered vs. teacher-centered instruction). However, all facilitators showed a moderate increase in comfort with the technology during the semester, and one participant showed remarkable gains in technology skills. The teaching theme provided insight into how facilitators foster learning in a PBL setting as compared to a traditional lecture. A high degree of variability in teaching styles was observed, but individuals' styles tended to remain stable over the course of the semester. Nevertheless, all facilitators interacted similarly with students, in a more caring and approachable manner, when compared to the classroom or clinic atmospheres.