The emergence and dissemination of multidrug-resistant bacterial pathogens is an increasing problem in veterinary medicine. Although the origin and means of dissemination have not been fully identified, infections caused by organisms such as MRSA are being reported more frequently.1,2 This phenomenon is of concern for a variety of reasons, including the effects on animal morbidity and mortality rates and the potential for zoonotic transmission. Additionally, as the incidence of multidrug-resistant bacterial infections increases, there may be increased pressure to use newer antimicrobials and those used primarily in human medicine. One such antimicrobial, of which use is commonplace in
Case Description—A 4-month-old American Paint filly was evaluated because of sudden onset of ataxia that progressed to recumbency. Five additional horses from the same and neighboring premises developed signs of poor performance, generalized weakness, ataxia, and recumbency; 2 of those horses were also evaluated. A new batch of a commercial feed supplement had been introduced to the horses' diet on each farm within the preceding 3 days.
Clinical Findings—Other than recumbency, findings of physical and neurologic examinations of the foal were unremarkable. The other 2 horses had generalized weakness and mild ataxia, and 1 horse also had persistent tachycardia. The foal had mild leukocytosis with neutrophilia, hyperglycemia, and mildly high serum creatine kinase activity. Results of cervical radiography, CSF analysis, and assessments of heavy metals and selenium concentrations in blood and vitamin E concentration in serum were within reference limits. Feed analysis revealed high concentrations of the ionophore antimicrobial salinomycin.
Treatment and Outcome—The 5 affected horses survived, but the foal was euthanized. At necropsy, a major histopathologic finding was severe vacuolation within neurons of the dorsal root ganglia, which was compatible with ionophore toxicosis. The surviving horses developed muscle atrophy, persistent weakness, and ataxia.
Clinical Relevance—In horses, ionophore toxicosis should be considered as a differential diagnosis for acute weakness, ataxia, recumbency, or sudden death. Furthermore, ionophore toxicosis should be considered as a cause of poor performance, weakness, muscle wasting, and cardiac arrhythmias in horses. Surviving horses may have impaired athletic performance.
Objective—To identify and critically evaluate the quality of evidence of the most commonly used pharmacologic, nutraceutical, and purported slow-acting drugs of osteoarthritis for the management of osteoarthritis in dogs by use of the FDA's evidence-based medicine scoring system.
Sample Population—16 clinical trials.
Procedures—A broad bibliographic search was performed prior to May 2006. Inclusion criteria focused on prospective trials evaluating commonly used medical treatment interventions for the management of osteoarthritis in dogs and published in peer-reviewed journals. The analysis consisted of the following: study design rating, quality factor rating, quantity rating, consistency rating, relevance to disease risk reduction rating, and cumulative strength of evidence ranking.
Results—4 trials evaluating meloxicam were rated as type I.Three trials evaluating carprofen were rated as type I, and 2 trials were rated as type III. One trial evaluating each of the following agents was rated as type 1: etodolac; P54FP; polysulfated glycosaminoglycan; and a combination of chondroitin sulfate, glucosamine hydrochloride, and manganese ascorbate. Two trials evaluating pentosan polysulphate and 2 trails evaluating green-lipped mussels were rated as type I. One trial evaluating hyaluronan was rated as type III.
Conclusions and Clinical Relevance—A high level of comfort exists for meloxicam that the claimed relationship is scientifically valid and that its use is clinically efficacious for the treatment of osteoarthritis in dogs.A moderate level of comfort exists for carprofen; etodolac; pentosan polysulphate; green-lipped mussels; P54FP; polysulfated glycosaminoglycans; and a combination of chondroitin sulfate, glucosamine hydrochloride, and manganese ascorbate. An extremely low level of comfort exists for hyaluronan.
The US FDA has approved a limited number of treatments for use in food fish. Two commercial aquaculture antimicrobials (oxytetracycline and sulfadimethoxine-ormetoprim combinations) were approved more than 20 years ago.1 Since these drugs are not effective against all bacteria and are not approved for use in many fish species, additional antimicrobials for use in aquaculture are needed. Because of the expensive drug approval process, pharmaceutical companies have been reluctant to develop new animal drugs for use in aquaculture. Passage of the MUMS Health Act in 2004 has given pharmaceutical manufacturers financial incentives to invest in development of new