Important metabolic changes occur during transition period of late pregnancy and early lactation to meet increasing energy demands of the growing fetus and for milk production. The aim of this investigation is to present an innovative and non-invasive tool using ewe earwax sample analysis to assess the metabolic profile in ewes during late pregnancy and early lactation. In this work, earwax samples were collected from 28 healthy Brazilian Santa Inês ewes divided into 3 sub-groups: 9 non-pregnant ewes, 6 pregnant ewes in the last 30 days of gestation, and 13 lactating ewes ≤ 30 days postpartum. Then, a range of metabolites including volatile organic compounds (VOC), amino acids (AA), and minerals were profiled and quantified in the samples by applying headspace gas chromatography/mass spectrometry, high performance liquid chromatography/tandem mass spectrometry, and inductively coupled plasma-optical emission spectrometry, respectively. As evident in our results, significant changes were observed in the metabolite profile of earwax between the studied groups where a remarkable elevation was detected in the levels of non-esterified fatty acids, alcohols, ketones, and hydroxy urea in the VOC profile of samples obtained from pregnant and lactating ewes. Meanwhile, a significant decrease was detected in the levels of 9 minerals and 14 AA including essential AA (leucine, phenyl alanine, lysine, isoleucine, threonine, valine), conditionally essential AA (arginine, glycine, tyrosine, proline, serine), and a non-essential AA (alanine). Multivariate analysis using robust principal component analysis and hierarchical cluster analysis was successfully applied to discriminate the three study groups using the variations of metabolites in the two stress states (pregnancy and lactation) from the healthy non-stress condition. The innovative developed method was successful in evaluating pre- and post-parturient metabolic changes using earwax and can in the future be applied to recognize markers for diagnosis, prevention, and intervention of pregnancy complications in ewes.

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The aim of this study was to evaluate the effect of daily biotin supplementation on the mineral composition and microstructure of the abaxial hoof wall in dairy heifers. The heifers were housed on a concrete floor and fed for weight gain more than 800 g per day, which is a challenging environment for the hoof. Twelve crossbred dairy heifers (Jersey × Holstein) were divided into two treatment groups. Animals in the control group (n = 6) received a diet without supplemental biotin, while the heifers in the biotin‐supplemented feed group (n = 6) each received 20 mg of biotin daily for 120 days. Samples of the abaxial hoof wall were collected from the outer claw of the fore and hind limb, before and after supplementation. The samples were evaluated by X‐ray fluorescence spectrometry, computed microtomography, atomic force microscopy and confocal laser scanning microscopy. Biotin supplementation increased the sulphur content and decreased the calcium and potassium content in the abaxial hoof wall. Biotin treatment also increased the percentage of horn tubules with smaller diameter marrow (17–51 µm). However, biotin did not influence the surface relief of the hoof wall, suggesting that its action is limited to the inner layers of the stratum corneum. Daily supplementation with 20 mg of biotin promoted changes in the mineral composition and microstructure of abaxial hoof wall of crossbred dairy heifers. These findings suggest biotin supplementation improves hoof quality and may help to understand the function of biotin in the stratum corneum.

An innovative method was developed to detect fluoroacetate poisoning in cattle by headspace/gas chromatographic analysis of earwax samples of intoxicated cattle. Samples were collected from 2 groups of cattle subjected to induced fluoroacetate intoxication, each group receiving a different dose of acetamide (antidote). Monofluoroacetic acid was detected in samples of intoxicated cattle in concentrations inversely proportional to the dose of acetamide. Thus, earwax analysis represents a successful approach for detection and monitoring of fluoroacetate poisoning.

RESUMO.-[Caracterização da acidose ruminal e da fase inicial da laminite induzidas por oligofrutose em bezerros mestiços.] 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 ABSTRACT.-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.

RESUMOO presente estudo objetivou descrever a rede vascular dos dígitos dos membros pélvicos de bovinos antes e após aplicação intrarruminal de oligofrutose, empregando a venografia. Utilizaram-se seis bovinos alocados em dois grupos (GI e GII), que receberam 13 e 17g/kg de oligofrutose, respectivamente. A venografia dos dígitos foi feita em quatro momentos: 15 dias antes (M0) e 36 horas (M1), sete dias (M2) e 30 dias (M3) após aplicação de oligofrutose. Mensurou-se a largura das veias visualizadas e avaliou-se possível supressão do fluxo sanguíneo dos vasos. A largura foi avaliada pela análise de variância (ANOVA) e pelo teste t (5%). Em M0, nas radiografias, foram identificadas 25 estruturas, incluindo veias, artérias e rede vascular. As veias mensuradas foram: digital dorsal comum III e dorsal da falange distal e os ramos plantares para o coxim digital do dígito lateral e medial. Apenas a v. digital dorsal comum III apresentou maior largura após 36 horas e constrição com 30 dias (P≤0,05) da aplicação de oligofrutose. Comparando-se os momentos, encontrou-se vasodilatação no M1 e vasoconstrição nos demais. A mensuração da largura dos vasos não sofreu (P≥0,05) interferência quando se compararam os grupos. Concluiu-se que a venografia dos dígitos de bovinos permite estudar e identificar alterações da vascularização.Palavras-chave: anatomia, bovino, laminite, oligofrutose, radiografia (Danscher et al., 2009). No estudo da laminite, a oligofrutose, carboidrato de alta fermentação, tem sido uma alternativa viável na indução do problema. A acidose ruminal desencadeada por esse carboidrato permite estudar alterações sequenciadas que ocorrem durante a instalação http://dx ABSTRACT

Resumo O leite e seus derivados são ricos em nutrientes e largamente consumidos pela população. Contudo, a presença de resíduos de substâncias químicas é frequente nesses produtos. Esse estudo objetivou realizar um diagnóstico sobre o uso de antibacterianos, avaliar o conhecimento sobre esses fármacos e condutas adotadas por produtores de leite em Goiás, Brasil. Foram visitadas 286 propriedades leiteiras em 36 municípios do estado, onde foram realizadas entrevistas com o proprietário ou mão de obra auxiliar. As perguntas abordavam parâmetros produtivos da propriedade e uso de antibacterianos. As respostas foram apresentadas em porcentagem e gráficos. A análise estatística foi realizada pelo teste de qui-quadrado de Pearson ao nível de significância de 5%. Apenas 26,2% dos produtores utilizavam antibacterianos indicados por veterinários e todos (100%) descartavam o leite com resíduos de forma inadequada. Dentre os 21 princípios ativos citados, os mais utilizados foram as tetraciclinas e penicilinas. As principais doenças tratadas com antibacterianos foram enterite (22,1%), tristeza parasitária bovina (21,1%) e mastite (19,4%). Observou-se que 37,4% dos entrevistados não souberam distinguir antibacterianos de outros medicamentos. Verificou-se que quanto mais especializada é a fazenda, maior é a assistência veterinária e maiores os cuidados para tratamentos com antibacterianos. A maioria dos entrevistados (51,7%) apresentava ensino fundamental incompleto. Esses resultados fornecem informações importantes sobre como os produtores rurais do estado de Goiás utilizam antibacterianos e servem como base para intervenções futuras. É evidente a necessidade de maior acesso dos produtores a serviços veterinários em Goiás, a fim de reduzir o uso desnecessário e inadequado de antibacterianos.

Milk and its derivatives are rich in nutrients and widely consumed by the population. However, the presence of chemical residues is frequent in these products. This study aimed to carry out a diagnosis of the use of antibacterials and evaluate the knowledge about these drugs and behaviors adopted by dairy producers in Goiás, Brazil. A total of 286 dairy farms in 36 municipalities in the State were visited and interviews were conducted with the owner or auxiliary workforce. The questions addressed the production parameters of the property and the use of antibacterials. The answers were presented in percentages and graphs. Statistical analysis was performed using Pearson’s chi-square test at a 5% significance level. Only 26.2% of the producers used antibacterials indicated by veterinarians and all producers (100%) disposed of milk with residues inappropriately. Tetracycline and penicillin were the most used among the 21 cited active principles. Enteritis (22.1%), cattle tick fever (21.1%), and mastitis (19.4%) were the main diseases treated with antibacterials. A total of 37.4% of respondents were unable to distinguish antibacterials from other drugs. Moreover, the more specialized the farm, the greater the veterinary assistance and the greater the care for antibacterial treatments. Most respondents (51.7%) had incomplete elementary education. These results provide important information about how rural producers in the State of Goiás use antibacterials and serve as a basis for future interventions. The need for greater access by producers to veterinary services in Goiás is evident to reduce the unnecessary and inappropriate use of antibacterials.