Evaluation of cats fed vegetarian diets and attitudes of their caregivers

OBJECTIVE: To determine motivation and feeding practices of people who feed their cats vegetarian diets as well as taurine and cobalamin status of cats consuming vegetarian diets. DESIGN: Cross-sectional study. ANIMALS: 34 cats that had been exclusively fed a commercial or homemade vegetarian diet and 52 cats that had been fed a conventional diet for > or = 1 year. PROCEDURES: Participants were recruited through a Web site and from attendees of a national animal welfare conference. Caregivers of cats in both groups answered a telephone questionnaire regarding feeding practices for their cats. Blood was obtained from a subset of cats that had been fed vegetarian diets. Blood and plasma taurine and serum cobalamin concentrations were measured. RESULTS: People who fed vegetarian diets to their cats did so largely for ethical considerations and were more likely than people who fed conventional diets to believe that there are health benefits associated with a vegetarian diet and that conventional commercial cat foods are unwholesome. Both groups were aware of the potential health problems that could arise from improperly formulated vegetarian diets. All cats evaluated had serum cobalamin concentrations within reference range, and 14 of 17 had blood taurine concentrations within reference range. CONCLUSIONS AND CLINICAL RELEVANCE: Vegetarian diets are fed to cats primarily for ethical considerations. Results of this study should aid practitioners in communicating with and providing advice to such clients.     

Volatile compounds in the skin and pulp of Queen Anne's pocket melon

The quantitative distribution of volatile compounds in the skin and pulp of Queen Anne's pocket melon [Cucumis melo var. dudaim (L.) Naudin] has been investigated. Volatile compounds were extracted by liquid-liquid microextraction (LLME) using chloroform and analyzed by GC-FID and GC-MS. Sixty volatiles, including 20 esters, 15 alcohols, 7 lactones, 7 aldehydes and ketones, 6 sulfur compounds, and 5 C(6) compounds, have been identified. Among them, 38 were reported for the first time in pocket melon, 10 of them have been, however, labeled "tentatively identified". The results showed that the levels of volatiles in skin were significantly higher than those observed in pulp. Eugenol, the major constituent in skin (15.3%), thioether esters, and lactones were thought to contribute significantly to the unique aroma of the pocket melon. Finally, the distribution of lactones was also found to be different in skin and pulp according to their carbon chain length.     

Use of a Plackett-Burman experimental design to examine the impact of extraction parameters on yields and compositions of pectins extracted from chicory roots (Chicorium intybus L.)

Chicory root pectin was isolated by acid extraction followed by alcohol precipitation. Because the extraction conditions have important effects on the features of pectins, an experimental design was used to study the influence of 17 different extraction parameters on yield and composition of pectin: pH, temperature, time of extraction, solid/liquid ratio, and different pretreatments of the pulps before extraction. Twenty extractions were conducted and examined for their significance on yield and sugar content using the Plackett-Burman factorial design. The acid extraction of chicory roots resulted in an average yield of 11% containing 86% of sugars. It was found that extraction temperature, time, protease pretreatment, water purity, and water washing of pulps significantly affected yield and pectin composition with an increase of yield and purity of pectin in harsher extraction conditions.     

Development of a buried bag technique to study biochars incorporated in a compost or composting medium

Purpose

The purpose was to develop a netbag technique suitable for burying biochar in a compost or composting medium, followed by its collection in a clean state (i.e., free of compost debris) without loss or damage, for physicochemical analyses. Collection in a clean state is required to ensure that the analytical data of various biochars are representative and comparable. Five criteria were identified to evaluate the suitability of netbag.

Materials and methods

A small netbag (3.5?×?3.5 cm) was developed using nylon fabric (30-μm mesh) to contain ～1 g of biochar. A production system was developed to make 15 netbags per batch. Unlike commonly used litterbags, polypropylene was used to seal netbags. Two experiments were conducted in which three biochars, made from macadamia nutshell, hardwood shaving, and chicken litter, were co-composted with chicken manure and sawdust and also incubated with a chicken litter-based commercial compost. Biochars were added at the rates of 5 or 10 % in the co-composting and 10 or 20 % in the incubation experiments. The biochar-containing netbags were buried in the co-composting and incubation mediums for 133 days. Various physicochemical analyses were conducted with netbag-biochars and their compost mediums.

Results and discussion

The netbags collected after both experiments showed no visible sign of degradation. The weight of netbag-biochars from co-composting and incubation systems did not reduce significantly over the experimental period, thereby indicating no loss of biochar. No visible evidence of entry of solid particles from compost medium was found on the netbag-biochars. Pretests indicated that the netbag and biochars absorbed pore solution from the medium. Findings showed that elements translocated between the netbag-biochar and compost medium. A colony of coccus bacteria was found on the surface of composted chicken litter biochar, denoting probable entry of bacteria from compost medium. Unlike conventional litterbags, the netbags were suitable for burying and extracting biochar in compost/composting mediums due to smaller size, smaller mesh, and strong sealing with polypropylene.

Conclusions

The netbags addressed all the five criteria. Therefore, it was concluded that, in the co-compost or incubated-compost medium, the biochar retained in the netbag and the biochar mixed with the medium were exposed to a similar bio-oxidative environment, and netbag-biochar represents the biochar in the medium. This means that these netbags can be used as a convenient means to examine the effects of the composting process or incubation in compost on biochar.

     

Accuracy of computed tomographic arthrography for assessment of articular cartilage defects in the ovine stifle

Articular cartilage defects are one of the features of osteoarthritis in animals and humans. Early detection of cartilage defects is a challenge in clinical veterinary practice and also in translational research studies. An accurate, diagnostic imaging method would be desirable for detecting and following up lesions in specific anatomical regions of the articular surface. The current prospective experimental study aimed to describe the accuracy of computed tomographic arthrography (CTA) for detecting cartilage defects in a common animal model used for osteoarthritis research, the ovine stifle (knee, femoropatellar/femorotibial) joint. Joints in cadaver limbs (n = 42) and in living animals under anesthesia (n = 13) were injected with a contrast medium and imaged using a standardized CT protocol. Gross anatomy and histological assessment of specific anatomic regions were used as a gold standard for the evaluation of sensitivity, specificity, negative predictive value, and positive predictive value for CTA identification of articular cartilage defects in those regions. Pooled estimated sensitivity and specificity were 90.32% and 97.30%, respectively, in cadaver limbs, and 81.82% and 95.24%, respectively, in living animals. Pooled estimated positive predictive value and negative predictive values were 98.25% and 85.71%, respectively, in cadaver limbs, and 81.82% and 95.24%, respectively, in living animals. The delineation of cartilage surface was good for anatomical regions most frequently affected by cartilage defects in the ovine stifle: medial femoral condyle, medial tibial condyle, and patella. This study supported the use of CTA as an imaging technique for detecting and monitoring articular cartilage defects in the ovine stifle joint.     

A mixed methods study of ruminant brucellosis in central-eastern Tunisia

In this study, we conducted an investigation to determine the true prevalence of bovine and ovine brucellosis in central-eastern Tunisia. A total of 1134 veterinary samples taken from 130 ruminant herds were screened for brucellosis using IS711-based real-time PCR assay. Sera collected from the ruminants were tested using the Rose Bengal test and indirect enzyme-linked immunosorbent assay. Based on serological and molecular results, the true adjusted animal population level prevalence was 23.5 % in cattle, against 13.5 % in sheep. In addition, the true adjusted herd level prevalence of brucellosis was 55.6 % in cattle and 21.8 % in sheep. A statistically significant association was found between vaginal and milk shedding for ruminants. In addition, our results showed that Brucella abortus could be responsible for bovine and ovine brucellosis. Multivariable logistic regression analysis at the animal population level indicated that age and origin variables were important risk factors for cattle. However, age and abortion variables were found to be associated with ovine brucellosis. At the herd level, risk factors for Brucella positivity were as follows: abortion and herd composition for cattle against herd composition, mortality rates, and hygiene for sheep. Animal hygiene, food quality, and sanitary practices on the farm should be applied as strategies to control brucellosis in herds.     

Spatio-temporal dynamics on a plot scale of cocoa black pod rot caused by <Emphasis Type="Italic">Phytophthora megakarya</Emphasis> in Cameroon

Black pod disease is caused by several species of Phytophthora. In Cameroon, the disease is mainly due to Phytophtora megakarya. The pathogen attacks cocoa pods and can lead to almost total production losses in a plot if no control measures are applied. To control the disease, several research programmes are being conducted: breeding for increased resistance, development of several biocontrol or agronomic methods. However, for better use of a specific method it is useful to have a good understanding of several epidemiological processes and more effectively know how the disease is distributed in the field. The purpose of this study was to describe the spatial development of the disease in several cocoa fields in Cameroon. In particular, we determined the spatial relation of the disease using several tools, including geostatistics models and Moran indices. The results indicated that the disease was not randomly distributed, while correlations between neighbouring cocoa trees existed. The relationships were detected up to a distance of between 7 and 9 m, revealing the wide dispersal pattern of the pathogen over short distances. No spatial structure was found in the spread of the disease in the oldest cocoa plantations and the inoculum was dispersed throughout the plot. Disease dispersal over short distances should make it possible to adapt control methods by attempting to confine the first disease foci in young plots. Research should also be undertaken to limit inoculum dispersal.     

Quantifying the effects of soil and climate on aboveground biomass production of <Emphasis Type="Italic">Salix miyabeana</Emphasis> SX67 in Quebec

Soil and climatic conditions for optimizing aboveground biomass yields of bioenergy short rotation coppices (SRCs) of Salix are not well elucidated. The objective of this study was to identify and quantify the limitations induced by soil and climate, and compare the magnitude of their effects, on annual aboveground yields across ten SRCs of Salix miyabeana SX67 in Quebec, Canada. The effects of weather variation between years on yields were also tested within locations. In five plots per SRC, soil bulk density, particle size, exchangeable cations and bulk composition were analysed, and moisture deficits were estimated using leaf δ¹³C. For each location, numerous weather variables were simulated for spring, summer and the whole growing season. Climate was calculated by averaging weather variables for growing seasons for which annual yields were available. Annual aboveground biomass yields were modelled using linear regression, partitioning of the variance and mixed models with soil, weather and climate variables as predictors. Across SRCs, silt content, soil organic matter, pH, exchangeable Ca and Mg, and total N and Zn were significantly and positively related to aboveground yields (adj. R ² ranging from 0.38 to 0.79). Generally, annual yields were negatively related to summer temperature within SRCs (adj. R ² = 0.92) and drought across SRCs (adj. R ² = 0.54). Partitioning of the variance revealed that soil variables (~80%) had a greater effect on productivity than did climate variables (~10%). In fact, soil properties buffered or exacerbated water shortages and, thus, had a preponderant effect on yield.