Use of Lactate in Small Animal Clinical Practice

Evaluation of two different etorphine doses combined with azaperone in blesbok (Damaliscus pygargus phillipsi) immobilisation

Chemical immobilisation is essential for veterinarians to perform medical procedures in wild African ungulates. Potent opioids combined with neuroleptic drugs are most often used for this purpose. The present study aimed at comparing the quality of immobilisation and effects on physiological variables between a high (high etorphine-azaperone [HE]: 0.09 mg kg-1) and low etorphine dose (low etorphine-azaperone [LE]: 0.05 mg kg-1), both combined with azaperone (0.35 mg kg-1), in 12 adult female boma-acclimatised blesbok. It was hypothesised that a reduction in etorphine's dose in combination with azaperone would result in less cardiorespiratory impairment but likely worsen the quality of immobilisation. Both treatments resulted in rapid induction and recovery times. Overall inter-treatment differences occurred in pulse rate (HE and LE: 52 ± 15 and 44 ± 11 beats minute-1, p 0.0001), respiratory rate (HE and LE: 15 ± 4 and 17 ± 4 breaths minute-1, p 0.006), partial pressure of exhaled carbon dioxide (HE and LE: 62.0 ± 5.0 and 60.0 ± 5.6 millimetre of mercury [mmHg], p 0.028) and arterial carbon dioxide (HE and LE: 58.0 ± 4.5 and 55.0 ± 3.9 mmHg, p 0.002). Both HE and LE led to bradycardia, hypertension and marked hypoxia to a similar extent. Furthermore, quality of induction, immobilisation and recovery were similar in both treatments. The role of azaperone in the development of cardiorespiratory compromise and gas exchange impairment that occurred when these combinations were used is still unclear. Further studies are recommended to elucidate drug- and dose-specific physiological effects in immobilised antelope.

Neurobiology of anesthetic-surgical stress and induced behavioral changes in dogs and cats: A review

The anesthetic-surgical stress response consists of metabolic, neuroendocrine, hemodynamic, immunological, and behavioral adaptations through chemical mediators such as the adrenocorticotropic hormone, growth hormone, antidiuretic hormone, cortisol, aldosterone, angiotensin II, thyroid-stimulating hormone, thyroxine, triiodothyronine, follicle-stimulating hormone, luteinizing hormone, catecholamines, insulin, interleukin (IL)-1, IL-6, tumor necrosis factor-alpha, and prostaglandin E-2. Behavioral changes include adopting the so-called prayer posture, altered facial expressions, hyporexia or anorexia, drowsiness, sleep disorders, restriction of movement, licking or biting the injured area, and vocalizations. Overall, these changes are essential mechanisms to counteract harmful stimuli. However, if uncontrolled surgical stress persists, recovery time may be prolonged, along with increased susceptibility to infections in the post-operative period. This review discusses the neurobiology and most relevant organic responses to pain and anesthetic-surgical stress in dogs and cats. It highlights the role of stress biomarkers and their influence on autonomous and demeanor aspects and emphasizes the importance of understanding and correlating all factors to provide a more accurate assessment of pain and animal welfare in dogs and cats throughout the surgical process.

Altered microbiota, fecal lactate, and fecal bile acids in dogs with gastrointestinal disease

The intestinal microbiota plays an important role in health and disease and produces, through fermentative reactions, several metabolic products, such as lactate, that can affect the host. The microbiota also interacts with and metabolizes compounds produced by the host, such as primary bile acids. Lactate and bile acids (BA) are of particular interest in gastrointestinal diseases because they have been associated with metabolic acidosis and bile acid diarrhea, respectively. The objectives of this study were to validate an enzymatic assay to quantify D-, L-, and total lactate in canine feces, and to characterize fecal lactate and BA concentrations as well as bacterial abundances in healthy dogs and dogs with gastrointestinal diseases. Fecal samples were collected from 34 healthy dogs, 15 dogs with chronic enteropathy (CE), and 36 dogs with exocrine pancreatic insufficiency (EPI). Lactate was quantified with an enzymatic assay, BA with gas chromatography-mass spectrometry, and 11 bacterial groups with qPCR. A fecal lactate reference interval was established from 34 healthy dogs and was 0.7–1.4 mM, 0.3–6.0 mM, and 1.0–7.0 mM for D-, L-, and total lactate, respectively. The assay to measure D-, L-, and total lactate in canine fecal samples was linear, accurate, precise, and reproducible. Significant increases in fecal lactate and decreases in secondary BA concentrations were observed in dogs with CE and dogs with EPI. Dogs with EPI had an increased abundance of Escherichia coli, Lactobacillus, and Bifidobacterium; a decreased abundance of Fusobacterium and Clostridium hiranonis; and a higher Dysbiosis Index when compared to healthy dogs. Further studies are necessary to determine the clinical utility of lactate and BA quantification in canine feces. These metabolites suggest functional alterations of intestinal dysbiosis and may become promising targets for further elucidating the role of the microbiota in health and disease.

The Role of Thiamine and Effects of Deficiency in Dogs and Cats

Recent pet food recalls for insufficient dietary thiamine have highlighted the importance of adequate thiamine intake in dogs and cats, as thiamine is an essential dietary nutrient with a critical role in energy metabolism. Prolonged thiamine deficiency leads to clinical signs that can span several organ systems, and deficiency can be fatal if not reversed. In this review, the current knowledge of thiamine metabolism will be summarized. Dietary recommendations for dogs and cats will be discussed, and the risk factors and clinical signs associated with thiamine deficiency will be examined.