Control of heifer mastitis by nutrition

Nutritional factors that are linked to mastitis in the mature dairy cow can be associated with mastitis in the first lactation cow as well. However, there may also be risk factors unique to the heifer due to differences in feeding management during rearing or pre-calving. Literature was reviewed to summarize current knowledge regarding links between heifer nutrition and mastitis with the potential to identify areas for future research. The preponderance of data relating nutrition and bovine mastitis involves selected micronutrients. Selenium and vitamin E enhance phagocytic activity and have been associated with decreased clinical mastitis risk. Copper has antioxidant functions and can reduce clinical mastitis in heifers. Zinc is implicated in maintaining the epithelial barriers to infection, but reports vary as to its role in udder health. Vitamin A and beta-carotene aid in maintaining the health of mucosal surfaces, and beta-carotene may also have antioxidant properties. Supplementation with vitamin A and beta-carotene has produced inconsistent results. Vitamin and mineral requirements of dairy heifers are generally influenced by growth rate and body weight relative to mature size, though little specific data is available. From a management standpoint, heifer rations should be supplemented where necessary, and a pre-fresh heifer diet is critical to assure that first lactation animals have adequate stores of minerals and vitamins. Adequate stores are necessary for transfer into colostrum by calving. Additional studies using field data and controlled studies are needed to further define the role of nutrition in animal health and in affecting specific mastitis-causing organisms.     

Squamous cell carcinoma originating from a cutaneous scar in a llama.

A nonhealing wound associated with a laceration in a 12-year-old llama was evaluated. Initial attempts at closure were unsuccessful and biopsy revealed scar tissue. Subsequent biopsies, 18 mo later, revealed squamous cell carcinoma with regional metastasis. This report describes squamous cell carcinoma, secondary to a traumatic wound in a llama.     

Diphenhydramine Intoxication in a Dog1

We report a case of diphenhydramine intoxication in a dog. A five month old intact male Labrador Retriever was presented after ingesting approximately 36 diphenhydramine tablets (50 mg/tablet; approximate ingested dose of 1800 mg or 67 mg/kg). Physical examination findings included severe ataxia, profound disorientation, severe continuous spastic muscle tremors, hyperthermia, tachycardia, tachypnea, and hyperesthesia. The dog was unresponsive to intravenous diazepam and phenobarbital, but rapidly responded to an intravenous bolus and subsequent continuous infusion of guaifenesin and supportive fluid therapy. The serum diphenhydramine level on admission was 537 ng/ml. The toxic level is not reported for dogs, but is considered>60 ng/ml in people. The dog was discharged 24 hours after admission with no apparent residual effects.     

Pharmacokinetics of amoxicillin/clavulanic acid combination after intravenous and oral administration in goats

Summary

The intravenous and oral pharmacokinetics of an amoxicillin and clavulanic acid combination (20 mg/kg of sodium amoxicillin and 5 mg/kg of potassium clavulanate) were studied in six goats. After intravenous administration the pharmacokinetics of both drugs could be described by an open two‐compartment model. Amoxicillin had a greater distribution volume (0.19 ± 0.01 l/kg) than clavulanic acid (0.15 ± 0.01 l/kg), whereas the distribution and elimination constants were higher for the latter, which was eliminated more quickly than amoxicillin. After oral administration of both drugs their pharmacokinetic behaviour was best described by an open one‐compartment model with first‐order absorption. Elimination half‐lives were twice as long after oral (2.15 ± 0.20 h and 1.94 ± 0.16 h for amoxicillin and clavulanic acid respectively) than after intravenous administration (1.20 ± 0.16 h and 0.86 ± 0.09, respectively). An apparent ‘flip‐flop’ situation was evident in this study. Bioavailability was 27% for amoxicillin and 50% for clavulanic acid.     

Validation of a new dental plaque quantification method in dogs

Current methods for the quantification of plaque accumulation in cats and dogs are well-accepted adaptations of traditional human models, but have required substantial modifications in order to compensate for the inherent differences in compliance, cooperation, and temperament between animals and humans. While these modifications have sought to maintain or improve upon the accuracy and reproducibility of the original methods, they also have increased the complexity of the technique and have required additional scorer time and animal cooperation, which leads to increased cost of trials. Therefore, research was directed toward the development and validation of a new substrate scoring system that reduces resources while maintaining or increasing the reproducibility attributed to the more traditional methods. This new gingival contour plaque index was shown to be accurate and reproducible, but used fewer animals, required less time, and eliminated the need for many of the specialized procedures required by traditional methods.     

Conjugated linoleic acid and black currant seed oil in the treatment of canine atopic dermatitis: a preliminary report

Although conjugated linoleic acid (CLA) shows inhibitory effects on histamine release, eicosanoid production and pruritus in laboratory rodents, its use in canine atopic dermatitis (AD) has not been reported. The aims of this study were to assess the efficacy of CLA, black currant seed oil (BSO) or a combination of both, compared to placebo, in dogs with AD and to evaluate any changes in fatty acid metabolism with these treatments. Twenty-four dogs with AD were randomly allocated to four groups, and were treated orally each day for two months with either 1 mL/10 kg CLA (80% purity), 1 mL/10 kg pure BSO, 1 mL/10 kg CLA+1 mL/10 kg BSO, or 1 mL/10 kg sugar syrup (placebo). Serum was obtained on days 0, 30 and 60 for analysis of CLA metabolites, linoleic acid (LA), gamma-linolenic acid (GLA), dihomo-gamma-linolenic acid (DGLA) and arachidonic acid (AA). At the same time point, the owners were asked to assess pruritus and the veterinarians evaluated any skin lesions present. Although the best clinical results occurred with BSO treatment alone, improvement of clinical signs and pruritus was not significant with any of the treatments. Serum levels of GLA and DGLA significantly increased in BSO-treated dogs, but not in the CLA+BSO group. CLA at the dosage used in this study was not efficacious in treating canine AD, whereas BSO may help some dogs with AD, although further studies are necessary before this can be recommended as a treatment.     

Severe alopecia due to demodicosis in roe deer (Capreolus capreolus) in Belgium

Demodex mites are part of the normal fauna of hair follicles of many, if not all, healthy mammal species. Normally these parasites live in harmony with their host, however in states of putative immunosuppression the acarids undergo excessive proliferation and cause clinical disease, which may be localised or generalised. This paper describes four cases of demodicosis in roe deer (Capreolus capreolus) with localised to generalised alopecia.     

Prevalence of Setaria equina microfilaraemia in horses in Hungary

Peripheral blood samples were collected randomly from 195 horses in various parts of Hungary, and the presence of microfilariae was evaluated by the Knott technique. On the basis of morphological identification 18 of the horses (9.2 per cent) were infected with Setaria equina, and the infection was confirmed in 10 animals by pcr and sequencing. The level of microfilaraemia was between 1 and 1138 larvae in 2 ml of blood. There was no correlation between the time of sampling or the sex of the animals (stallions versus mares) and the prevalence of infection, but the prevalence decreased with age. There was a significant association between the prevalence of microfilaraemia and the presence of still waters; positive samples were collected either in the region of Lake Balaton, the largest lake in the country, or at places with nearby ponds.