Characterization of ruminal acidosis and initial phase of laminitis inducted by oligofructose in crossbred calves / Caracterização da acidose ruminal e da fase inicial da laminite induzidas por oligofrutose em bezerros mestiços

One of the ways to study cattle laminitis is its experimental induction by supplying a large amount of high fermentation carbohydrate. The most effective protocol until now has been the use of oligofructose. The objective of this study was to evaluate clinical and histological aspects of the hoof in experimental induction of ruminal acidosis and laminitis in calves using oligofructose. Six crossbred (Bos taurus x Bos indicus) yearling calves divided into Group I (GI) and Group II (GII) were used. Animals in GI and GII received intraruminal oligofructose in doses of 13 and 17g/kg, respectively. During 28 hours the calves were clinically evaluated and 30 hours after induction, samples were taken from coronary and abaxial wall of the hoof for histologic evaluation. Were noticed signs of ruminal and metabolic acidosis like rumen distension with fluid, diarrhea, ruminal pH reduction and, at blood gas analysis, pH and bicarbonate below reference range. Lameness was not observed however, some animals had a slower gait and apathy, possibly due to metabolic acidosis, though. Histologically, typical lesions of laminitis like circulatory changes and inflammatory infiltrate in the dermis, irregularities and areas of detachment at basement membrane and morphologic changes in cells from basal epidermis were found. The protocol induced, in the first 30 hours, clinical signs of ruminal and metabolic acidosis and low grade histologic lesions in the digits. Lameness and digit pain were not observed, characterizing the prodromic phase of the disease.(AU)

Uma das formas de se estudar a laminite bovina é sua indução experimental por meio do fornecimento de grande quantidade de carboidrato de alta fermentação. O protocolo mais eficaz até o momento foi o uso de oligofrutose. Objetivou-se avaliar aspectos clínicos e histológicos dos dígitos de bovinos na indução experimental de acidose ruminal e laminite usando oligofrutose. Utilizaram-se seis bezerros mestiços (Bos taurus x Bos indicus) de um ano, divididos em Grupo I (GI) e Grupo II (GII). Os animais em GI e GII receberam oligofrutose por via intrarruminal nas doses de 13 e 17g/kg respectivamente. Os bovinos foram avaliados clinicamente por 28 horas e fragmentos de coroa e muralha abaxial dos dígitos foram colhidos para histologia 30 horas após a indução. Foram identificados sinais de acidose ruminal e metabólica como distensão ruminal com líquido, diarreia e baixo pH ruminal. Os resultados de hemogasometria indicaram baixos pH e nível plasmático de bicarbonato. Os animais não apresentaram claudicação, entretanto, observaram-se apatia e marcha mais lenta, atribuídas à acidose metabólica. Histologicamente foram observadas lesões indicativas de laminite como alterações circulatórias e infiltrado inflamatório na derme, irregularidades e áreas de destacamento da membrana basal e alterações morfológicas de células da epiderme basal. O protocolo induziu, nas primeiras 30 horas, sinais de acidose ruminal e metabólica e lesões histológicas de baixa intensidade nos dígitos. Não foi observada claudicação ou sensibilidade nos dígitos, caracterizando a fase prodrômica da enfermidade.(AU)

Evaluation of cardiorespiratory and biochemical effects of ketamine-propofol and guaifenesin-ketamine-xylazine anesthesia in donkeys (Equus asinus).

OBJECTIVES: To evaluate the cardiorespiratory and biochemical effects of ketamine-propofol (KP) or guaifenesin-ketamine-xylazine (GKX) anesthesia in donkeys. STUDY DESIGN: Prospective crossover trial. ANIMALS: Eight healthy, standard donkeys, aged 10 ± 5 years and weighing 153 ± 23 kg. METHODS: Donkeys were premedicated with 1.0 mg kg(-1) of xylazine (IV) in both treatments. Eight donkeys were administered ketamine (1.5 mg kg(-1)) and propofol (0.5 mg kg(-1) for induction, and anesthesia was maintained by constant rate infusion (CRI) of ketamine (0.05 mg kg(-1) minute(-1)) and propofol (0.15 mg kg(-1) minute(-1)) in the KP treatment. After 10 days, diazepam (0.05 mg kg(-1)) and ketamine (2.2 mg kg(-1)) were administered for induction, and anesthesia was maintained by a CRI (2.0 mL kg(-1) hour(-1)) of ketamine (2.0 mg mL(-1), xylazine (0.5 mg mL(-1)) and guaifenesin (50 mg mL(-1)) solution. Quality of anesthesia was assessed along with cardiorespiratory and biochemical measurements. RESULTS: Anesthetic induction took longer in GKX than in KP. The induction was considered good in 7/8 with KP and in 6/8 in GKX. Anesthetic recovery was classified as good in 7/8 animals in both treatments. Xylazine administration decreased heart rate (HR) in both treatments, but in KP the HR increased and was higher than GKX throughout the anesthetic period. Respiratory rate was higher in GKX than in KP. PaO(2) decreased significantly in both groups during the anesthetic period. Glucose concentrations [GLU] increased and rectal temperature and PCV decreased in both treatments. Arterial lactate [LAC] increased at recovery compared with all time points in KP. [GLU] and calcium were higher in GKX than in KP at recovery. CONCLUSION AND CLINICAL RELEVANCE: These protocols induced significant hypoxemia but no other cardiorespiratory or metabolic changes. These protocols could be used to maintain anesthesia in donkeys, however, they were not tested in animals undergoing surgery.

Cone beam computed tomography and intraoral radiography for diagnosis of dental abnormalities in dogs and cats.

The development of veterinary dentistry has substantially improved the ability to diagnose canine and feline dental abnormalities. Consequently, examinations previously performed only on humans are now available for small animals, thus improving the diagnostic quality. This has increased the need for technical qualification of veterinary professionals and increased technological investments. This study evaluated the use of cone beam computed tomography and intraoral radiography as complementary exams for diagnosing dental abnormalities in dogs and cats. Cone beam computed tomography was provided faster image acquisition with high image quality, was associated with low ionizing radiation levels, enabled image editing, and reduced the exam duration. Our results showed that radiography was an effective method for dental radiographic examination with low cost and fast execution times, and can be performed during surgical procedures.

Cone beam computed tomography in the diagnosis of temporomandibular joint alterations in cats.

The aim of this study was to describe the use of cone beam computed tomography as an auxiliary method to diagnose changes to the temporomandibular joints in cats. We used five cats of various ages, breeds and genders that showed clinical signs consistent with changes in the temporomandibular joint. Cone beam computed tomography enables a complete and thorough examination of the temporomandibular joints by allowing the evaluation of selected images as a whole. It also enables the identification of all anatomical structures and any changes that may be present. The results showed that this method is effective in confirming or ruling out changes in the temporomandibular joint in cats, such as disjunctions of the palatine raphe; fractures of the mandibular symphisis, zygomatic bone and condylar; and dental resorption.

Mitochondrial DNA control region polymorphism in the population of Alagoas state, north-eastern Brazil.

The sequences of the two hypervariable (HV) segments of the mitochondrial DNA (mtDNA) control region were determined in 167 randomly selected, unrelated individuals living in the state of Alagoas, north-eastern Brazil. One hundred and forty-five different haplotypes, associated with 139 variable positions, were determined. More than 95% of the mtDNA sequences could be allocated to specific mtDNA haplogroups according to the mutational motifs. Length heteroplasmy in the C-stretch HV1 and HV2 regions was observed in 22 and 11%, respectively, of the population sample. The genetic diversity was estimated to be 0.9975 and the probability of two random individuals presenting identical mtDNA haplotypes was 0.0084. The most frequent haplotype was shared by six individuals. All sequences showed high-quality values and phantom mutations were not detected. The diversity revealed in the mitochondrial control region indicates the importance of this locus for forensic casework and population studies within Alagoas, Brazil.