New PCR Heartworm Test?

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HW Multiplex qPCR in Dogs

The study focuses on addressing the challenge of diagnosing canine heartworm (Dirofilaria immitis) infections, a serious mosquito-borne disease affecting dogs. Traditionally, the modified Knott’s test has been used for detecting heartworm microfilariae, but it's labor-intensive and its accuracy depends on technician expertise. With heartworm reports increasing and resistance to preventatives emerging, there's a push towards more reliable, efficient diagnostics like multiplex qPCR. 

Multiplex qPCR, targeting both the heartworm DNA and its symbiotic bacteria Wolbachia, offers a promising alternative. This study aimed to evaluate whether qPCR could replace the modified Knott’s test for quantifying microfilariae levels more rapidly and accurately. Despite some discrepancies between the qPCR and the modified Knott’s test results, qPCR showed potential as a proxy, detecting a significant portion of cases that the modified Knott’s test identified as not achieving a >90% reduction in microfilariae following treatment. 

Furthermore, the study highlighted the role of Wolbachia in heartworm infections and its potential as a diagnostic marker and treatment target. It also touched on the challenge of detecting macrocyclic lactone (ML) resistance, a growing concern for canine health. The research indicated that while ML resistance markers identified in the USA were not found in the Australian heartworm population, a comprehensive approach combining both phenotypic and genotypic analyses might be needed to understand ML resistance fully. 

In conclusion, multiplex qPCR represents a valuable tool for diagnosing canine heartworm, capable of offering rapid, accurate microfilariae quantification with less hands-on time compared to traditional methods. This molecular approach could streamline the detection and management of heartworm infections, although further studies with larger sample sizes are recommended to refine and validate the methodology. 

Daisy Ching-Wai Lau, Rosemonde Isabella Power, Jan Šlapeta, Exploring multiplex qPCR as a diagnostic tool for detecting microfilarial DNA in dogs infected with Dirofilaria immitis: A comparative analysis with the modified Knott’s test, VeterinaryParasitology, Volume325,2024, https://doi.org/10.1016/j.vetpar.2023.110097. 

Bottom line — May be useful when it is fully developed.

Best Way to Discuss Obesity in Pets

This study focuses on the significant issue of obesity in dogs, highlighting the multifaceted causes and adverse health consequences associated with the condition, including metabolic dysfunction, decreased quality of life, and shortened lifespan. Recognizing the professional responsibility of veterinary teams to address pet obesity, the research explores the challenges faced by veterinary professionals in communicating about weight management with clients, noting a hesitancy to engage in conversations about pet obesity due to concerns about offending clients and potentially harming the client-veterinarian relationship. 

To improve communication and client engagement in weight management for pets, the study examines the application of discrete choice methods (DCMs) to identify dog owners' preferences for receiving information from the veterinary team about managing an overweight or obese dog. DCMs, which force respondents to make trade-off decisions, reveal that dog owners prioritize information on the impact of obesity on life expectancy above other attributes, followed by the timeline for developing arthritis, future quality of life, and cost of food. 

The findings suggest that veterinary professionals should include discussions on the potential extension of lifespan and delayed onset of arthritis when communicating with clients about pet obesity. Emphasizing these aspects, alongside other factors like quality of life and cost, may encourage clients to take action against their pet's excess weight. The study underlines the importance of veterinary teams being proactive in discussing weight management from an early stage, focusing on tangible benefits such as improved life expectancy and joint health, to motivate clients towards maintaining a healthy weight for their pets. 

The study's limitations include its reliance on hypothetical scenarios and a quantitative survey, which may not fully capture the complexities of real-life decision-making processes of dog owners. Future research should consider incorporating qualitative methods to understand the motivations behind pet owners' preferences and explore additional factors influencing decisions on pet weight management. 

Davies, A. R., Sutherland, K. A., Groves, C. N. H., Grant, L. E., Shepherd, M. L., & Coe, J. B. (2024). Impact on life expectancy was the most important information to clients when considering whether to take action for an overweight or obese dog. Journal of the American Veterinary Medical Association https://doi.org/10.2460/javma.23.12.0697 

Bottom line — Extension of lifespan and delay of arthritis are the best approaches.

PAGH Saftety in Horses.

The study explores the effects of serial administration of 4% Polyacrylamide Hydrogel (PAHG) in normal equine fetlock joints, focusing on clinical, histological, and synovial fluid biomarker impacts. Polyacrylamide hydrogels are utilized for intra-articular lubrication in osteoarthritic joints for both humans and horses, offering potential relief from lameness and acting as an effective lubricant for damaged cartilage surfaces. Unlike the 2.5% PAHG initially designed as an aesthetic filler and later used for intra-articular therapy, the 4% PAHG is specifically engineered to mimic the viscoelastic properties of normal synovial fluid, aiming to lubricate damaged cartilage surfaces efficiently. 

The study showed that the 4% PAHG, when administered in a series of injections to equine fetlock joints, did not result in any negative effects up to 56 days following the last treatment. This finding was consistent with previous observations that this PAHG variant is slowly phagocytosed within the joint with minimal inflammatory response. The research aimed to ascertain whether serial injections of 4% PAHG would adversely affect articular cartilage or the synovial membrane, with results indicating minimal differences compared to saline control groups, suggesting the safety and effectiveness of PAHG in surface and boundary lubrication of cartilage. 

Notably, the presence of PAHG led to visible joint thickening due to its hydrophilic nature, but without pathological changes in cartilage, synovial fluid, or membrane. Histological assessments revealed similar scores for cellular infiltration, vascularity, and fibrosis between treated and control groups, with differences attributed to PAHG presence in the synovial membrane. These outcomes suggest that while PAHG induces changes within the joint, these are not indicative of harmful effects but rather of its function as a lubricant and protector of joint surfaces. 

The study highlights the distinct properties and applications of PAHGs, underscoring that differences in concentration, cross-linkage, and manufacturing processes yield materials with unique behaviors in biomedical contexts. The findings advocate for the safe use of 4% PAHG in equine joint treatment, with no significant adverse effects noted from serial injections. However, the study also acknowledges its exploratory nature and the need for further research to fully understand the long-term impacts and optimal use of PAHG in veterinary medicine. 

McClure, S. R., Peitzmeier, M. D., Jackman, B. R., Evans, R. B., Ziegler, C. L., & Ganta, C. K. (2024). Serial injections of 4% polyacrylamide hydrogel have no detrimental effects in equine joints following clinical, histologic, and synovial biomarker evaluation. American Journal of Veterinary Research https://doi.org/10.2460/ajvr.24.01.0016 

Bottom line — Seems to be safe for joints.

Just putting things in perspective …