Polyodontia in donkeys

Polyodontia is defined as the presence of teeth in excess of the normal dental formula. In equids, supernumerary teeth are uncommon but, when present, are usually located mainly in the caudal aspects of the cheek teeth rows (distomolars), also being found adjacent to normal cheek teeth or even in an ectopic location. It is believed that this disorder is a result of an inappropriate differentiation of dental germinal tissue during gestational development, with external trauma also acting as an initiating factor, when teeth germs are affected. The presence of these abnormal teeth can lead to axial displacement, dental overgrowths, dental‐related soft tissue damage, diastemata formation, periodontal disease and development of secondary sinusitis. A large prospective, cross‐sectional study was performed in 800 donkeys, with the aim to investigate the prevalence and aetiopathogenesis of clinically diagnosed oral and dental disorders. Polyodontia was recorded in 2.25% of the donkeys, presenting 36 supernumerary teeth, with 2.80% being incisors and 97.20% cheek teeth, with prevalence increasing with age. The caudal aspects of the maxillary cheek teeth rows were the most common locations for supernumerary teeth development (distomolars). The mandible was far less commonly affected than the maxilla. Although polyodontia is uncommon in donkeys, it should be considered in the differential diagnosis of dental disease. A methodical oral examination and a complete radiographic survey of the entire dental arcades are crucial for a correct early diagnosis and treatment plan implementation. The increasing prevalence of fully erupted supernumerary teeth recorded in older groups suggested a late onset eruption process, and therefore, in donkeys undergoing regular dental prophylaxis, the presence of previously unnoticed supernumerary teeth should always be sought.     

Cardiopulmonary effects during anaesthesia induced and maintained with propofol in acepromazine pre‐medicated donkeys

ObjectiveTo evaluate the cardiopulmonary effects of anaesthesia induced and maintained with propofol in acepromazine pre-medicated donkeys.Study designProspective experimental study.AnimalsSix healthy male donkeys weighing 78–144 kg.MethodsDonkeys were pre-medicated with intravenous (IV) acepromazine (0.04 mg kg⁻¹). Ten minutes later, anaesthesia was induced with IV propofol (2 mg kg⁻¹) and anaesthesia maintained by continuous IV infusion of the propofol (0.2 mg kg⁻¹ minute⁻¹) for 30 minutes. Baseline measurements of physiological parameters, and arterial blood samples were taken before the acepromazine administration, then 5, 15, 30, 45, and 60 minutes after the induction of anaesthesia. Changes from baseline were analysed by anova for repeated measures.ResultsWhen compared with baseline (standing) values, during anaesthesia heart rate increased throughout: significant at 5 (p = 0.001) and 15 (p = 0.015) minutes. Mean arterial blood pressure increased significantly only at 15 minutes (p < 0.001). Respiratory rate and arterial pH did not change significantly. PaO₂ was lower throughout anaethesia, but this only reached significance at 15 minutes (p = 0.041). PaCO₂ was statistically (but not clinically) significantly reduced at the times of 30 (p = 0.02), 45 (p = 0.01) and 60 (p = 0.04). Rectal temperature decreased significantly at all times of the study.Conclusions and clinical relevanceAdministration of propofol by the continuous infusion rate for the maintenance of anaesthesia resulted in stable cardiopulmonary effects and could prove to be clinically useful in donkeys.     

Pharmacology and therapeutics in donkeys

Therapeutics are often administered to donkeys based on dosage and intervals recommended for horses because very few drugs have donkey‐specific label indications. Yet differences between donkeys and horses in drug distribution, metabolism and elimination have been noted for most therapeutic agents studied. These differences can be partially explained by the donkey's unique physiology. Since their ancestors evolved in a desert environment, the modern donkey exhibits qualities that allow them to tolerate dehydration better than the horse and recover more quickly from its effects. Fluid balance and body water compartment partitioning differ from the horse and may have implications regarding drug distribution. Since donkeys are preferential browsers, differences in diet may have influenced evolutionary differences in metabolic disposition of drugs. It is important to acknowledge these differences when designing dose regimes for donkeys based on horse protocols in order to avoid either lack of efficacy or toxicity.     

Epidural anaesthesia using lignocaine, bupivacaine or a mixture of lignocaine and bupivacaine in dogs

The time to loss of interdigital reflex, duration of action, duration of muscle relaxation and cardiorespiratory effects were compared after epidural block using lignocaine, bupivacaine or a combination of lignocaine and bupivacaine in dogs. Dogs were pre-medicated with methotrimeprazine, anaesthesia was induced with thiopentone, in order to facilitate epidural puncture, and a lumbosacral epidural block was performed. Body temperature fell after pre-medication, thiopentone and epidural anaesthesia. Minimal changes were observed in arterial O₂ saturation, end tidal CO₂, respiratory rate, heart rate and mean arterial blood pressure. The combination of bupivacaine with lignocaine produced a shorter time to loss of interdigital reflex than bupivacaine alone, longer analgesia than lignocaine alone and longer muscle relaxation than either lignocaine or bupivacaine. The combination appeared to be the best choice when surgical time is prolonged.     

Lungworm: (Dictyocaulus arnfieldi) infection in donkeys.

The clinical, parasitological and pathological findings in a group of six donkeys naturally infected with D arnfieldi larvae are described. One animal had to be sacrificed at an early date because it developed pneumonia. The remaining five were unthrifty, showed mild clinical respiratory signs and had heavy strongyle infections. They had varying numbers of adult worms in the airways of the lungs and eggs were found coiled up in the smaller bronchi where they had apparently lead to an obstruction to airflow in that segment. The most striking gross pathological changes were circular discrete areas of over-inflation surrounding such bronchi. Histologically the infected bronchi exhibited a marked bronchiolitis with goblet cell hyperplasia and a mainly lymphoid inflammatory infiltrate. These areas also showed a localised bronchiolitus and overinflated alveolar tissue although true emphysema was not present. It is postulated that the parasite is well-adapted to its host and is able to survive for long periods within the lung without causing a debilitating amount of damage to the host. The immunological aspects of the infection are discussed briefly.     

Idiopathic typhlocolitis in 40 aged donkeys

Typhlocolitis was diagnosed in 40 aged donkeys at routine post mortem examinations subjected to euthanasia for colic‐related clinical signs at The Donkey Sanctuary. Gross pathological changes included oedema, ulceration and haemorrhage involving the caecum and ventral colon. Histopathology indicated endoparasite and bacterial associated inflammation in 20 and 11 cases, respectively. Bacterial culture in 18 cases did not yield a definite aetiological agent. Other management and stress related factors were looked at to identify obvious risk factors. This report describes the clinical, biochemical and haematological parameters and pathological changes observed in 40 donkeys diagnosed with typhlocolitis.     

Endometritis in she donkeys in Egypt

The endometrial necropsies of 165 she donkeys were examined and the endometria were classified into four grades according to histological features (I, IIa, IIb, III). Category I was observed in 86 cases (52.12%) and diagnosed as normal endometria. Category IIa was observed in 18 cases (10.91%) and diagnosed as slight endometritis. Category IIb was observed in 28 cases (16.97%) and diagnosed as moderate endometritis (two to four nests/field), while category III was observed in 33 cases (20%) and diagnosed as severe endometritis (eight nests/field). A bacteriological examination was carried out and oestrogen and progesterone were estimated. Our results indicate that endometritis and the prognosis of fertility in she donkeys were more or less parallel to mares.     

Conjunctival fungal flora in healthy donkeys

OBJECTIVE: To identify and quantify ocular fungi from healthy donkeys living in the center of Italy. ANIMALS STUDIED: One hundred and two Amiata donkeys were examined. PROCEDURES: Conjunctival swabs from both eyes were seeded onto Sabouraud dextrose agar (SDA) and malt extract agar (MEA), and incubated at 25 degrees C over a 10-day period. Filamentous fungi identification was achieved to the genus level; yeast colonies were identified for macro-micromorphologic and physiological characteristics. RESULTS: Eighty-one donkeys out of 102 (79.4%) were positive for fungi; 47/102 (46.1%) had positive cultures from both eyes. Most frequently recovered fungal genera were Aspergillus spp., Penicillium spp., Cladosporium spp., Acremonium spp. Different fungal genera and/or species were recovered from the same donkey in 43 cases (42.1%). Yeasts were isolated from five subjects; the yeasts were never associated with molds. The number of colony forming units (CFU) ranged from 1 to 100. CONCLUSIONS: Aspergillus was the most commonly isolated fungal genus (33%). This result agrees with the findings of similar surveys carried out in horses. There was a remarkable presence of fungi and perfect forms. These observations may be explained by the optimal conditions for presence and development of fungi in the conjunctival fornix microenvironment in Amiata donkeys.     

Anthelmintic control of lungworm in donkeys

A field study was designed to investigate the re-establishment of patent lungworm infections in donkeys following an anthelmintic treatment regime which was effective against Dictyocaulus arnfieldi. In April 1979 faecal samples from 259 donkeys were examined and each animal classified as a negative, low positive or high positive excretor of lungworm larvae. During the summer the control group of 126 donkeys showed an increase in the number of excretors from 80 per cent in April to 91 per cent in October. At the same time there was a rise in the faecal larval output of individual animals so that by October 59 per cent were classified as high positive compared with only 20 per cent in April. The treated group of 133 donkeys received 3.5 g mebendazole daily for 5 days during April and as a result the number of excretors fell from 66 per cent pretreatment to 23 per cent one month after treatment. Despite exposure to infected pastures throughout the summer this figure was maintained at a comparatively low level and by October patent infections had been re-established in only 15 per cent of the donkeys that were negative after treatment.     

Epidemiological observations on Gasterophilus intestinalis and G. nasalis in donkeys from Morocco.

During a 24 month period, 198 donkeys were examined for Gasterophilus intestinalis and Gasterophilus nasalis larvae. Gasterophilus intestinalis was found in 97.5% and G. nasalis in 95.5% of donkeys. The third instars (L3) of both species occurred during all months of the year and so did the second instars (L2), except in April (G. nasalis) and May (G. intestinalis). Over 75% of the animals had up to 200 larvae and 1.5% had over 600 larvae. The maximum number of both L2 and L3 larvae found in any animal was 418 G. intestinalis, 433 G. nasalis and 715 of both species combined. The seasonal variation in the numbers and development status of larvae indicated that the period of greatest activity of adult flies of G. intestinalis was from August/September to November, and that of G. nasalis from May to September. Consequently, the L2 larvae in the stomachs were in peak numbers between November and January for G. intestinalis and between July and September for G. nasalis. The L3 larvae of G. intestinalis had peak numbers between December and July, and those of G. nasalis between October and March. During January-March, most of the L2 larvae of G. nasalis were trapped in polypous nodules near the pyloric end of the stomach. It is concluded that the high-risk period for infection is during late spring and autumn, leading to the heavy larval burden of Gasterophilus in the stomach of donkeys during winter.     

Prevalence of lungworm D. arnfieldi (Cobbold 1884) in donkeys in Denmark and in horses in herds together with donkeys (author's transl)

During a 5 months' period from January to May 1981 faecal samples of 176 donkeys from 59 herds all over the country were examined at the Institute of internal medicine, The Royal Veterinary and Agricultural University, Copenhagen. In addition, the investigation also included 106 horses from 30 of the donkey herds and 34 horses hospitalized with symptoms of dyspnoea and chronic coughing. In all, 87.5% of the donkeys were shown to excrete D. arnfieldi larvae, often in very high numbers, and the larval excretion was the only symptom of lungworm infection. There was no significant correlation between larval excretion and age, sex or herd size. In horses, the frequency of D. arnfieldi infection was approximately the same in the horses from donkey herds and in horses hospitalized due to chronic cough (10.4% and 8.8% resp.). In contrast to the donkeys, the infection in horses was always accompanied by dyspnoea and coughing.     

Epidural analgesia and anesthesia.

This review describes the beneficial effects of the use of epidural drugs for pre-emptive analgesia, intraoperative analgesia with an inhalant-sparing effect, and prolonged postoperative analgesia. Epidural morphine oxymorphone, or hydromorphone is recommended for use in small animals in combination with a local anesthetic of appropriate duration for procedures involving the hind end, although epidural morphine or hydromorphone may be more appropriate for procedures on the thorax and forelimbs. Side effects are few and can usually be easily managed, with the benefits outweighing any detrimental effects that might occur.