Ryan Michael Yamka

Evaluation of cognitive learning, memory, psychomotor, immunologic, and retinal functions in healthy puppies fed foods fortified with docosahexaenoic acid–rich fish oil from 8 to 52 weeks of age

OBJECTIVE To assess effects of foods fortified with docosahexaenoic acid (DHA)-rich fish oil on cognitive, memory, psychomotor, immunologic, and retinal function and other measures of development in healthy puppies. DESIGN Evaluation study. ANIMALS 48 Beagle puppies. PROCEDURES Puppies were assigned to 3 groups after weaning (n = 16/group) and received 1 of 3 foods (low-DHA, moderate-DHA, or high-DHA food) as their sole source of nutrition until 1 year of age. Visual discrimination learning and memory tasks, psychomotor performance tasks, and physiologic tests including blood and serum analysis, electroretinography, and dual-energy x-ray absorptiometry were performed at various time points. Anti-rabies virus antibody titers were evaluated 1, 2, 4, and 8 weeks after vaccination at 16 weeks of age. RESULTS Foods had similar proximate analysis results but varied in concentration of DHA from fish oil; the high-DHA food also contained higher concentrations of vitamin E, taurine, choline, and l-carnitine than did other foods. The high-DHA group had significantly better results for reversal task learning, visual contrast discrimination, and early psychomotor performance in side-to-side navigation through an obstacle-containing maze than did the moderate-DHA and low-DHA groups. The high-DHA group had significantly higher anti-rabies antibody titers 1 and 2 weeks after vaccination than did other groups. Peak b-wave amplitudes during scotopic electroretinography were positively correlated with serum DHA concentrations at all evaluated time points. CONCLUSIONS AND CLINICAL RELEVANCE Dietary fortification with fish oils rich in DHA and possibly other nutrients implicated in neurocognitive development following weaning improved cognitive, memory, psychomotor, immunologic, and retinal functions in growing dogs.

Use of serum biomarkers to predict the development and severity of osteochondrosis lesions in the distal portion of the femur in pigs

OBJECTIVE To evaluate the use of serum biomarkers of cartilage and bone metabolism to predict the occurrence and severity of osteochondrosis (OC) lesions in the distal portion of the femur in growing swine. ANIMALS 71 gilts. PROCEDURES At an abattoir, serum samples for analysis of 10 biomarkers indicative of cartilage and bone metabolism were obtained prior to processing of the pigs. The distal portion of each pigs left femur was directly examined and cut into longitudinal sections to evaluate the number and severity of abnormalities on the external surface, articular cartilage, and growth plate. Each specimen was categorized as with (n = 56) or without (15) OC, and an overall OC severity score was assigned to affected pigs. Logistic and linear regression analyses were performed to predict odds of OC on the basis of biomarker concentrations and predict the severity of OC values in affected pigs, respectively. RESULTS Compared with values in unaffected pigs, serum concentrations of C-propeptide of type II collagen (CPII) and cartilage oligomeric matrix protein were significantly increased and concentrations of carboxy-terminal telopeptide of type II collagen 3/4-length fragment (C2C) and pyridinoline cross-links were significantly decreased in affected pigs. A 2-fold increase in CPII concentration increased the odds of pigs having OC by a factor of 97 (95% confidence interval, 6 to infinity). Changes in serum C2C concentration accounted for 49% of the variation in overall OC severity score. CONCLUSIONS AND CLINICAL RELEVANCE Assessment of serum biomarker concentrations may be useful in the diagnosis of OC and aid in reduction of lameness in swine herds.

Evaluation of body composition and cartilage biomarkers in large-breed dogs fed two foods designed for growth

OBJECTIVE To evaluate cartilage and bone biomarkers and body composition in growing large-breed dogs consuming a diet designed for growth. ANIMALS 43 large-breed 2 month-old-puppies. PROCEDURES Dogs were randomly assigned to receive 1 of 2 foods until 18 months of age. Dogs were evaluated at 2, 5, 12, and 18 months of age via dual energy x-ray absorptiometry (DEXA), CBC, serum biochemical profile, and concentrations or activities of taurine, vitamin E, fatty acids, glutathione peroxidase, C-propeptide of type II collagen (CPII), cartilage oligomeric matrix protein (COMP), carboxy-terminal cross-linked fragment of type II collagen (CTXII), bone specific alkaline phosphatase (BAP), osteocalcin, ghrelin, and growth hormone. RESULTS Blood components largely reflected the composition of the foods. Dogs fed the food with a higher concentration of protein, calcium, n-3 fatty acids, and antioxidants had a lower percentage of body fat and greater percentage of lean body mass at 5, 12, and 18 months of age, and higher CPII:CTXII ratio and lower COMP at 18 months of age. The BAP activity, osteocalcin concentration, and CTXII concentration declined with age, whereas COMP concentration and CPII concentration were similar at all time points for both foods. CONCLUSIONS AND CLINICAL RELEVANCE The BAP activity, osteocalcin concentration, and CTXII concentration were greater during growth than at 18 months of age. The food that was proportionately higher in protein, calcium, n-3 fatty acids, and antioxidants increased lean body mass and may have positively affected cartilage turnover as maturity was attained. Whether the rate of cartilage turnover during growth affects development of orthopedic disease or arthritis in adulthood has yet to be determined.

In vitro disappearance characteristics of selected categories of commercially available dog treats.

Pet owners desire treats with adequate nutritional profiles, functional benefits, long-lasting properties and an interactive nature. Therefore, it is pivotal to understand the digestion characteristics of treats produced by different processing methods and having variable nutritional composition. The objective of the present study was to measure in vitro disappearance characteristics of selected categories of commercially available treats. In vitro procedures developed by Boisen and Eggum in 1991 were modified to handle larger sample sizes. Treat samples were evaluated in triplicate. Following incubation, in vitro DM disappearance (DMD) was calculated. In vitro DMD of selected treats varied widely. For the gastric phase, DMD ranged from 6·9 to 88·8 %, whereas intestinal phase digestion resulted in a DMD range of 10·7–100·0 % (P < 0·05). Because of differences in treat composition and size, they were divided into six categories: Biscuit, Bone, Chew, Dental, Meat Product and Rawhide. In general, Bone was the least digestible treat category in both gastric and intestinal phases. Meat Product and Rawhide treats had a DMD of 71·5–100 % after the intestinal phase, whereas Biscuit had values above 93 %. Chew and Dental treats had a wide DMD range (54·5–100 %). Understanding the DMD of commercially available treats is important to verify their safety for consumption and potential digestibility once ingested. These data indicate wide variation in DMD among and within different treat categories. This information will assist pet food sale associates, pet owners and veterinarians to make more educated decisions when it relates to selection and recommendations about commercially available treats. Future work is needed to expand the knowledge on in vitro DMD and safety of treats and to further investigate their impact on in vivo DM digestibility once fed to dogs.

In vivo measurement of flatulence and nutrient digestibility in dogs fed poultry by-product meal, conventional soybean meal, and low-oligosaccharide low-phytate soybean meal

OBJECTIVE To determine an optimal window for determining peak flatulence and evaluate the effects of oligosaccharides and supplemental beta-mannanase in soybean meal-based diets on nutrient availability and flatulence. ANIMALS 6 dogs. PROCEDURES Dogs were used in a 2 x 3 factorial arrangement of treatments in a 6 x 6 Latin square experiment to evaluate the digestibility, flatulence, and fecal odor metabolites of low-oligosaccharide low-phytate soybean meal (LLM), conventional soybean meal (SBM), and poultry by-product (PBP) meal diets with or without supplemental beta-mannanase (5 g/kg). RESULTS Enzyme supplementation had no effect on total tract dry matter (DM), nitrogen digestibility, or digestible energy; however, differences between protein sources did exist for total tract DM digestibility and digestible energy. The PBP meal had higher DM digestibility and digestible energy (mean, 0.913 and 4,255 cal/g), compared with soy-based diets (mean, 0.870 and 4,049 cal/g). No differences were detected for any treatment regardless of protein source or addition of supplemental enzyme for any flatulence components analyzed. No differences were detected for all fecal odor metabolites regardless of addition of supplemental enzyme; however, differences between protein sources were detected. The PBP meal had lower concentrations of carboxylic acids and esters and higher concentrations of heterocycles, phenols, thio and sulfides, ketones, alcohols, and indoles than LLM and SBM. CONCLUSIONS AND CLINICAL RELEVANCE Diets containing < 22.4 g of stachyose/kg and < 2 g of raffinose/kg did not alter digestibility or increase flatulence in dogs.