Comparison of the cognitive palatability assessment protocol and the two-pan test for use in assessing palatability of two similar foods in dogs

OBJECTIVE: To compare preferences of dogs for 2 similar foods by use of 2 distinct methods (the cognitive palatability assessment protocol [CPAP] and the 2-pan test). ANIMALS: 13 Beagles. PROCEDURE: 6 dogs were trained in a 3-choice object-discrimination-learning task in which their nonpreferred objects were associated with a reward of a lamb-based or chicken-based food. The number of choices for each object was used to determine food preferences. Preference of the same foods was also assessed by use of a 2-pan test in which all 13 dogs were provided the 2 foods in identical bowls. The amount of each food consumed in 10 minutes was used to determine food preference. RESULTS: All dogs had a noticeable preference for the chicken-based food during the CPAP. Once established, preferences remained consistent and were not affected by satiety. The 2-pan test identified a preference for the chicken-based food in dogs with previous exposure to the food but only a weak and nonsignificant preference for the same food in dogs without previous exposure. Food preferences in the 2-pan test varied considerably. Total food consumption and the ability to detect a preference were reduced when dogs were fed prior to testing. CONCLUSIONS AND CLINICAL RELEVANCE: The CPAP provides a reliable measure of food preference that requires few test subjects. The 2-pan test reveals similar preferences but with variability in data that requires larger numbers of subjects and is susceptible to effects from prior exposure and feeding of the test foods to the subjects.     

Influence of lifetime food restriction on causes, time, and predictors of death in dogs

OBJECTIVE: To describe effects of lifetime food restriction on causes of death and the association between body-mass characteristics and time of death in dogs. DESIGN: Paired-feeding study. ANIMALS: 48 dogs from 7 litters. PROCEDURES: Dogs were paired, and 1 dog in each pair was fed 25% less food than its pair mate from 8 weeks of age until death. Numerous morphometric and physiologic measures were obtained at various intervals throughout life. Associations of feeding group to time and causes of death were evaluated, along with important associated factors such as body composition components and insulin-glucose responses. RESULTS: Median life span was significantly longer for the group that was fed 25% less food, whereas causes of death were generally similar between the 2 feeding groups. High body-fat mass and declining lean mass significantly predicted death 1 year prior to death, and lean body composition was associated with metabolic responses that appeared to be integrally involved in health and longevity. CONCLUSIONS AND CLINICAL RELEVANCE: Results were similar to results of diet restriction studies in rodents and primates, reflecting delayed death from species- and strain-specific intrinsic causes. Clinicians should be aware that unplanned body mass changes during mid- and later life of dogs may indicate the need for thorough clinical evaluation.     

A survey to investigate movements off sheep and cattle farms in New Zealand,with reference to the potential transmission of foot-and-mouth disease

AIM: To quantify the numbers and extent of movements off sheep and cattle farms in New Zealand, in order to construct more realistic simulation models to investigate how infectious diseases such as foot-and-mouth disease (FMD) might spread.

METHODS: Farmers from 500 randomly selected farms, comprising 100 from each of the following sectors, viz beef, dairy, grazing/dairy heifer rearing, sheep, and mixed sheep and beef, were asked to fill in diaries in which they recorded the movements of all animals, products, people, vehicles and equipment coming on to or leaving their farms during two separate 3-week periods, representing relatively ‘busy’ and ‘quiet’ times of the year with respect to livestock movements. Where possible, the destination of each movement was identified and geo-coded, to allow the distance travelled to be calculated. Each movement was then classified according to the risk of transfer of FMD virus (FMDV), should the disease have been present on the study farm at the time of the movement. The data were then analysed to establish movement frequencies and distributions of distances travelled, by the different pastoral livestock sectors.

RESULTS: Two hundred and seventeen farmers returned one or more diaries. One hundred and ninety-three farmers completed a Busy-period diary, recording a total of 12,052 movements off their farms, a crude average of 62.4 per 3-week period, or 2.97 per day. Of these, 4.0% involved the transport of livestock, equating to 0.12 livestock consignments per day. In contrast, 186 Quiet-period diaries were returned, recording a total of 10,885 movements off, representing a crude average of 58.5 during the 3-week period, or 2.78 per day. Of these, 2.1% involved livestock, equating to 0.06 livestock consignments per day. The mean and median distances travelled during the Busy periods were 30.9 km and 13.1 km, respectively (range 0–1,167 km). In comparison, the mean and median distances travelled during Quiet periods were 41.3 and 14 km, respectively (range 0.4–1,203 km).

CONCLUSIONS: People, vehicles, livestock and other items can travel off pastoral livestock farms in New Zealand to other farms either directly or via saleyards over extensive distances. This has implications for the potential spread of infectious diseases such as FMD. Movement parameters intended for use in the InterSpread Plus inter-farm simulation model of FMD were established, which will facilitate the prediction of likely spread and efficacy of controls in the unlikely event of a real-life outbreak.     

A comparison of predictions made by three simulation models of foot-and-mouth disease

AIMS: To describe results of a relative validation exercise using the three simulation models of foot-and-mouth disease (FMD) in use by the quadrilateral countries (QUADS; Australia, Canada, New Zealand, and United States of America; USA).

METHODS: A hypothetical population of farms was constructed and, following the introduction of an FMD-like disease into a single farm, spread of disease was simulated using each of the three FMD simulation models used by the QUADS countries. A series of 11 scenarios was developed to systematically evaluate the key processes of disease transmission and control used by each of the three models. The predicted number of infected units and the size of predicted outbreak areas for each scenario and each model were compared using the Kruskal-Wallis test. Agreement among the three models in terms of geographical areas predicted to become infected were quantified using Fleiss' Kappa statistic.

RESULTS: Although there were statistically significant differences in model outputs in terms of the numbers of units predicted to become infected, the temporal onset of infection throughout the simulation period, and the spatial distribution of infected units, these differences were generally small and would have resulted in the same (or similar) management decisions being adopted in each case.

CONCLUSIONS: Agreement among the three models in terms of the numbers of premises predicted to become infected, the temporal onset of infection throughout the simulation period, and the spatial distribution of infected premises provides evidence that each of the model developers are consistent in their approach to simulating the spread of disease throughout a population of susceptible individuals. This consistency implies that the assumptions taken by each development team are appropriate, which in turn serves to increase end-user confidence in model predictions.

CLINICAL RELEVANCE: Relative validation is one of a number of steps that can be undertaken to increase end-user confidence in predictions made by infectious disease models.     

In vitro effects of lactoferrin on lipopolysaccharide-induced proliferation, gene expression, and prostanoid production by bovine peripheral blood mononuclear cells

Objective-To evaluate the effect of lactoferrin on lipopolysaccharide (LPS)-induced proliferation of bovine peripheral blood mononuclear cells (PBMCs), gene expression of inflammatory mediators, and production of prostanoids in vitro. Sample Population-PBMCs isolated from 15 Holstein bull calves. Procedures-Mixed populations of PBMCs were isolated by differential centrifugation. Proliferation assays were conducted in 96-well plates designed to allow addition of lactoferrin (200 ng/mL) with and without LPS (1 mug/mL) in a checkerboard design. Incorporation of (3)H-thymidine was used to determine proliferation of PBMCs. Prostaglandin E(2) production was determined in culture-conditioned medium by use of enzyme immunoassay. Effects of lactoferrin on LPS-induced gene expression of cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-9 were monitored by use of PCR assays. Results-Lactoferrin supplementation significantly reduced LPS-induced incorporation of (3)H-thymidine and production of prostaglandin E(2) by PBMCs. Lactoferrin reduced LPS-induced expression of COX-2 and MMP-9 mRNA. Conclusions and Clinical Relevance-Lactoferrin reduced LPS-induced cellular proliferation, inflammatory mediator gene expression, and prostaglandin E(2) production by bovine PBMCs in vitro. These effects may be beneficial in reducing the impact of endotoxemia in neonates.     

Nutritional management of gastric ulceration

Gastric ulcers are common in horses and equine gastric ulcer syndrome describes ulcers in the distal oesophagus, nonglandular and glandular stomach as well as the proximal duodenum. Ulcers in the distal oesophagus and nonglandular region of the stomach are probably caused by hydrochloric acid, whereas ulcers in the glandular stomach and proximal duodenum are likely to be caused by a breakdown in the mucosal defence mechanisms. Regardless of the location of ulcers, initial treatment with pharmacological agents is necessary to suppress hydrochloric acid; however, nutrition and management changes are required to maintain ulcer healing and help prevent recurrence. In addition, many dietary supplements have been marketed to help maintain stomach health and some scientific data on their effects on gastric ulcer scores and gastric juice pH are presented.     

Determination of serologic and colostral response in late-gestation cows vaccinated with a Mycoplasma bovis bacterin

OBJECTIVE: To determine whether vaccinating cows during late gestation against Mycoplasma bovis will result in adequate concentrations of M bovis-specific IgG(1) in serum, colostrum, and milk. ANIMALS: 78 dairy cows. PROCEDURES: Serum samples were obtained 60 and 39 days prior to expected parturition in vaccinated and control cows from a single herd. Serum and colostrum samples were also obtained at parturition. Milk samples were obtained 7 to 14 days after parturition. Samples were analyzed for anti-M bovis IgG(1) concentrations. RESULTS: Prior to vaccination, control and vaccinated cows had similar anti-M bovis IgG(1) concentrations. After initial vaccination and subsequent booster and at parturition, there was a significant difference between the 2 groups, with vaccinated cows having higher IgG concentrations. Colostrum from vaccinated cows had higher anti-M bovis IgG(1) concentrations, compared with control cows; however, IgG(1) concentrations in milk did not differ between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE: Vaccination of late-gestation cows resulted in increased concentrations of anti-M bovis IgG(1) in colostrum. However, ingestion of colostrum by calves may not guarantee protection against M bovis infection.     

Economic costs associated with two testing strategies for screening feeder calves for persistent infection with bovine viral diarrhea virus

OBJECTIVE: To develop partial budgets of the economic costs of 2 test strategies for screening cattle for persistent infection with bovine viral diarrhea virus (BVDV). DESIGN: Partial budget analysis. ANIMALS: 938 calves arriving at 2 stocker operations. PROCEDURE: Calves were tested to determine prevalence of persistent BVDV infection. Test strategies that were evaluated included a single-test strategy consisting of immunohistochemical staining of skin biopsy specimens from all animals and a 2-test strategy consisting of polymerase chain reaction (PCR) assaying of pooled blood samples followed by immunohistochemical staining of skin biopsy specimens from animals in pools for which assay results were positive. Break-even costs (i.e., cost of persistent BVDV infection per animal necessary to justify whole-herd diagnostic testing) associated with each test strategy were calculated as a function of disease prevalence and test cost. RESULTS: Apparent prevalence of persistent BVDV infection was 0.32%. Sensitivity and specificity of the PCR assay for pooled samples were 100% and 89.7%, respectively. Regardless of the prevalence of persistent BVDV infection, the break-even cost for the 2-test strategy was lower than the break-even cost for the single-test strategy. However, the economic advantage was greatest when prevalence was low. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that using a 2-test strategy to screen cattle for persistent BVDV infection, whereby the first test involves PCR assaying of pooled samples and the second involves immunohistochemical testing only of those animals represented in pooled samples with positive assay results, will reduce the cost of screening incoming feedlot cattle, compared with immunohistochemical testing of all animals.