Immune-mediated canine and feline keratitis.

Although the normal cornea is devoid of vasculature and lymphatics, there are still several immune-mediated corneal conditions that can occur in dogs and cats. An overview of corneal immunology is presented. Diseases of dogs, including chronic superficial keratitis, superficial punctate keratitis, and canine adenovirus endotheliitis, as well as feline diseases, including eosinophilic keratitis and herpesvirus-related conditions, are discussed.     

Dietary effects on canine and feline behavior.

The effects of dietary deficiency, including both malnutrition and deficiency of specific vitamins, on behavior is discussed with special emphasis on the growing kitten and puppy. The effect of caloric restriction on behavior is reviewed so that owners can be advised what to expect when their dog is placed on a reducing diet. The evidence for influence of dietary protein and tryptophan on canine aggression is presented. The effect of special diets on canine cognitive dysfunction is reviewed.     

Update on canine and feline fungal diseases.

Systemic fungal diseases cause significant morbidity and mortality in dogs and cats. Blastomycosis, histoplasmosis, coccidiomycosis, and cryptococcosis represent the four most common systemic fungal diseases. Young adult, large breed dogs generally are predisposed; cats usually do not have predictable predispositions. Intact cell-mediated immunity is essential to initial resistance to infection and response to treatment in animals. Several body systems can be affected. Diagnosis can be confirmed on the basis of clinical signs and demonstration of the causative organism. Serology is helpful with coccidiomycosis and cryptococcosis. Treatment is complicated by limited availability of fungicidal antimicrobials and the necessity of long-term treatment with expensive drugs.     

Effects of surgical sterilization on canine and feline health and on society

Surgical sterilization of dogs and cats is a well-accepted measure for population control in some countries, but is considered unethical as an elective surgery in other countries. This is a review of what is known regarding positive and negative effects of gonadectomy surgery on individual animals and on societal management of unowned dog and cat populations.     

Perspectives on canine and feline hepatozoonosis

Two species of Hepatozoon are currently known to infect dogs and cause distinct diseases. Hepatozoon canis prevalent in Africa, Asia, southern Europe, South America and recently shown to be present also in the USA causes infection mainly of hemolymphoid organs, whereas Hepatozoon americanum prevalent in the southeastern USA causes myositis and severe lameness. H. americanum is transmitted by ingestion of the Gulf Coast tick Amblyomma maculatum and also by predation on infected prey. H. canis is transmitted by Rhipicephalus sanguineus, in South America also by Amblyomma ovale, and has also been shown to be transmitted transplacentally. Hepatozoonosis of domestic cats has been described mostly from the same areas where canine infection is present and the exact identity of the species which infect cats, their pathogenicity and vectors have not been elucidated. The diagnosis of hepatozoonosis is made by observation of gamonts in blood smears, histopathology, PCR or serology. The main treatment for H. canis is with imidocarb dipropionate whereas H. americanum infection is treated with an initial combination of trimethoprim-sulfadiazine, pyrimethamine and clindamycin followed by maintenance with decoquinate. Treatment for both diseases has not been reported to facilitate complete parasite elimination and new effective drugs are needed for the management of these infections. Prevention of hepatozoonosis should be based on avoidance of oral ingestion of infected tick vectors and infected prey.     

Current research in canine and feline pheromones.

Pheromonotherapy seems to be a new therapeutic approach allowing practitioners to tackle the treatment of behavioral disorders in a natural, specific, and safe way. Although the efficacy of pheromones has been assessed in some specific behavioral problems, it seems that their range of action could cover the wide field of reduction of stress. Therefore, the use of pheromones should not be reduced to treatment of behavioral disorders (potentially associated with psychotropes or a behavioral modification program) but should be included in a strategy of improving the welfare of pets in veterinary structures (during examination and hospitalization) and in breeding networks (separation from the mother and transport). Moreover, further studies may allow the veterinary practitioner to use pheromone analogues in the field of diagnostics to determine the behavioral status of a pet (e.g., anxious or not, dominant or not). Pheromonotherapy is at its beginning, and the use of pheromones in various fields of medicine is heartening.     

Diagnostic imaging of the canine and feline ear.

Radiographic evaluation of the tympanic bulla is limited. Improper obliquity or angulation of the skull for radiographs or malpositioning of the tongue can result in an inadequate study [4]. Additionally, because of the complex anatomy of the canine and feline skull, with superimposition of multiple osseous structures, radiography can result in false-negative examinations or understimation of the disease present [2]. When compared with surgical findings of 19 clinical cases of presumptive middle ear disease, false-negative radiographic findings were found in 25% of the surgically confirmed cases of otitis media [4]. Therefore, radiographs are not considered to be a highly sensitive mode of diagnosing otitis media. Radiographs may be helpful in determining lysis associated with neoplasia; however, the extent of involvement is still underestimated. In a study comparing CT and radiographic evaluation of otitis media, CT was determined to be more sensitive but less specific than radiography [11]. CT is the preferred modality for the evaluation of the tympanic bulla at our institution. This opinion may be biased by the fact that most cases are presented for recurrent or chronic otitis. Although radiography is more accessible, the availability of CT in local referral settings is increasing as opposed to being limited to university settings. After the cost (i.e., anesthesia, radiographs) and amount of time necessary to make optimum radiographic studies are taken into account, a CT study may actually be faster and more informative. Given our preference for the CT examination, the cost of the examination has been adjusted to make it more appealing to the owner and clinician. For example, a bulla CT study is only 1.3 times the cost of a radiographic bulla study. In conclusion, imaging of the ear canal can provide important information about ear disease, including unilateral or bilateral ear disease, the degree of middle or inner ear involvement, peripheral versus central vestibular disease, an infectious or inflammatory versus neoplastic process, the chronicity of the disease process, involvement of adjacent structures, and postsurgical complications.     

Effect of electrocardiographic filters on the R-amplitude of canine electrocardiograms

Lead II electrocardiograms (ECGs) were recorded in 88 dogs ranging in weight from 3 to 50 kg. A commercial direct-writing electrocardiograph was used to record the ECGs, first with manual HUM filter (notch filter at 50/60 Hz) and EMG filter (cut-off frequency of -3 dB at 35 Hz) on, immediately followed by a recording with both filters off. The mean (sd) reduction in R-amplitude with the filters on was 53(18) per cent with a range from 22 to 100 per cent and a median value of 51 per cent. The R-amplitude with the filters off was related to the R-amplitude with the filters on, making it possible to correct for the effect of the filters. The reduction in R-amplitude was inversely correlated with the weight of the dog and with the duration of the QRS-complex. Other known changes induced by filters, such as the elimination of notches and the slurring of the junction between the QRS-complex and the ST-interval were also observed. The inverse relationship between the weight of the dog and the magnitude of the reduction in R-amplitude by the filters indicates that ECG machines with different characteristics should ideally be used to record ECGs in dogs of different sizes.     

Basics in canine and feline rhinoscopy

Patients suffering from upper respiratory disease such as chronic nasal congestion, sneezing, nasal discharge, and epistaxis invite complete evaluation of their paired nasal cavities. Thorough assessment of these cavities employs sundry diagnostic procedures that enable the investigating clinician to characterize the internal structures of the nasal cavities. After the conscious patient undergoes a complete physical examination, a gross assessment of its external nasal structures is established and areas of physical asymmetry are noted. A working anatomic knowledge of these asymmetric foci helps to guide the next diagnostic steps. The patient is then placed under general anesthesia, during which, in list order, imaging studies, rhinoscopy, and nasal biopsy or foreign body retrieval, are performed.     

CpG oligodeoxynucleotides stimulate canine and feline immune cell proliferation.

Oligodeoxynucleotides (ODNs) with unmethylated CpG dinucleotide motifs may be useful as non-specific immune system stimulants and adjuvants for protein or nucleic acid vaccines in humans and other primates. They may also be useful in cancer immunotherapy and in the modulation of allergic responses or mucosal immunity. To begin to determine the potential utility of CpG ODN technology in small animal veterinary medicine, we developed procedures to analyze the effects of CpG ODN on canine and feline blood, spleen and lymph node (LN) cells. We find that certain CpG ODN cause good lymphocyte proliferation (as monitored by [(3)H]-thymidine incorporation) in both canine and feline spleen and LN cells, but not in blood. This overall stimulatory effect of CpG ODN on spleen and LN cells is CpG dependent. The reverse sequences, GpC ODNs, do not cause significant lymphocyte proliferation in the cat; however, dogs are more sensitive to stimulation by the non-specific immune effects of the phosphorothioate backbone. We conclude that unmethylated CpG ODNs may also have potential uses as immune stimulants for vaccines and other antimicrobial agents in veterinary medicine for companion animals.     

Topical treatment of canine and feline pyoderma

Abstract This paper is a review of commonly used topical antibacterial medications: benzoyl peroxide, chlorhexidine, povidone iodine, ethyl lactate, triclosan, mupirocin, neomycin, polymyxin B, bacitracin and fusidic acid. Included is a review of the pharmacokinetics, modes of action, adverse effects and clinical uses in veterinary dermatology. General recommendations for topical antibacterial therapy are presented. Résumé— Cet article est une revue des topiques antibactériens les plus couramment utilisés: peroxyde de benzoyle, chlorhexidine, povidone iodée, lactate d'éthyle, triclosan, mupirocine, néomycine, polymyxine B, bacitracine et acide fucidique. Il inclut notamment une revue des pharmacocinétiques, des modes d'action, des effets secondaires et des indications thérapeutiques de ces produits en dermatologie vétérinaire. Les indications générales du traitement topique antibactérien sont présentées. [Guaguere, E. Topical treatment of canine and feline pyoderma. (Traitement topique des pyodermites canines et félines). Veterinary Dermatology 1996; 7 : 145–151.] Resumen Este articulo es una revisión de los productos tópicos antibacterianos más frecuentemente utilizados: peróxido de benzoilo, clorhexidina, povidona yodada, etillactato, triclosan, mupirocina, neomicina, polimixina B, bacitracina y ácido fusidico. Se incluye una revisión de la farmacocinética, mecanismos de acción, efectos colaterales y sus usos clínicos en dermatologia veterinaria. Se presentan recomendaciones generales para la terapia antibacteriana tópica. [Guaguere, E. Topical treatment of canine and feline pyoderma. (Tratamiento topico de la pioderma canina y felina). Veterinary Dermatology 1996; 7 : 145–151.] Zusammenfassung— Diese Veröffentlichung besteht in einer Übersicht von häufig verwendeten topischen antibakteriellen Arzneimitteln: Benzoylperoxid, Chlorhexidin, Povidon-Jod, Ethyllaktat, Triklosan, Mupirocin, Neomycin, Polymyxin B, Bacitracin und Fusidinsäure. Mit eingeschlossen ist eine Übersicht über Pharmakokinetik, Wirkungsweise, Nebenwirkungen und klinische Anwendung in der Veterinärdermatologie. Allgemeine Empfehlungen für die lokale antibakterielle Therapie werden dargestellt. [Guaguere, E. Topical treatment of canine and feline pyoderma (Lokale Behandlung von kaninen und felinen Pyodermien). Veterinary Dermatology 1996; 7 : 145–151.]