Resumo: Para padronização de uma técnica manual para a obtenção de plasma rico em plaquetas (PRP) autólogo em bovinos com custo reduzido (método manual) e de boa qualidade (capacidade de concentrar plaquetas, alta concentração de fatores de crescimento e contaminação reduzida com leucócitos e eritrócitos), que poderá ser utilizado como um agente modulador da resposta imune de vacas com diferentes enfermidades, 450 ml de sangue total de nove vacas clinicamente saudáveis e com perfil hematológico normal foi coletado em bolsas de sangue CPDA-1 e processado dentro de quatro horas após a coleta. O sangue foi separado em alíquotas para avaliar 8 protocolos (P) de centrifugação dupla que variaram quanto a velocidade e o tempo de centrifugação. A contagem de plaquetas, eritrócitos e leucócitos na suspensão obtida (PRP) foi realizada pelo método manual em câmara de Neubauer: P5 (400g e 800g ambos durante 10 min) foi o protocolo com maior número de plaquetas, seguido por P3 (120g e 473g ambos durante 10 min), P4 (300g e 640g durante 10 min cada), P6 (640g durante 10 min e 640g durante 5 min), P8 (640g durante 5 min e 120g durante 10 min) e P7 (720g e 720g durante 5 min) e diferentes (p<0,05) dos menores valores encontrados em P1 (120g e 240g, ambos por 5 minutos) e P2 (120g e 473g ambos por 5 min). Em relação aos eritrócitos, P8, P7, P6, P5 e P4 apresentaram menores concentrações e maiores valores (p<0,05) foram observados em P3 e P2. Menores quantidades de leucócitos foram observadas em P5, P6, P8 e P7 com o maior valor obtido em P2 (p<0,05). Todos os protocolos (P1 a P8) foram eficientes em concentrar plaquetas sendo o valor mais baixo (3,65±0,79) observado em P1. Em relação aos fatores de crescimento ao se mensurar TGF- 1, os protocolos P1 e P8 evidenciaram valores mais elevados. De acordo com os resultados obtidos os protocolos P5 e P8 apresentaram os melhores resultados para confecção de PRP bovino.
RESUMO.-A intoxicação por plantas é sabidamente uma das principais causas de morte de bovinos adultos no Brasil. Uma vez que pouco pode ser feito no que diz respeito ao tratamento destas intoxicações, os esforços devem se concentrar na adoção de medidas profiláticas alternativas, como a utilização de uma espécie menos sensível no local de Plant poisoning is known to be one of the most important causes of death of adult cattle in Brazil. As there are not many possibilities for treatment, all efforts must focus on application of alternative prophylactic measures, among them the use of a less sensitive animal species in areas of the occurrence of certain plants. This study aimed to ascertain the sensibility of goats to crotalarias (Crotalaria spectabilis and Crotalaria juncea), so that this animal species could be used as a prophylactic measure against those plants poisonous for cattle. Single or daily doses of seeds of Crotalaria spectabilis and Crotalaria juncea were given to eight young adult goats of both sexes divided randomly in two groups of four goats, e.g. one group for each plant. None of the four goats that received seeds of Crotalaria juncea developed clinical sings of poisoning or showed changes in the biochemistry examination. Out of the four goats that received seeds of Crotalaria spectabilis, three died. One goat received a 20g/kg single dose of seeds and developed signs of acute poisoning. Postmortem and histopathological examination revealed marked centrilobular hemorrhagic necrosis. The other two goats developed chronic poisoning by the administration of 2g/kg daily doses of seeds for 35 and 150 days respectively. One goat showed severe interstitial pneumonia and mild hepatic lesions, while the other goat presented only chronic hepatic lesions. Both goats showed transient changes in the biochemistry examination. The fourth goat received a 10g/kg single dose of seeds and did not develop significant clinical or biochemical changes. The results of the present study showed that goats are not indicated to be used as a prophylactic measure against poisoning by Crotalaria spectabilis, but can be recommended as a prophylactic measure against poisoning by Crotalaria juncea.
Cattle (Bos taurus and Bos indicus) are organised on the basis of leadership and dominance in such a manner that a disturbance by an external stressor causes negative effects on their health, productivity, well-being, and behaviour. One of these effects is the excessive release of glucocorticoids, which results in increased alertness. We evaluated the action of exogenous oxytocin (OT) on serum cortisol levels in crossbred Red Angus heifers. Twelve Red Angus crossbred heifers were moved daily from the pasture to the corral in weeks 1 and 2 for adaptation to human contact and handling in the cattle crush. In weeks 3 and 4, they were divided into two groups of six (T1 and T2). The T1 group was administered 20 IU (2 mL) of OT via intramuscular injection and the T2 group was administered 2 mL of saline solution 0.85% (SS). In weeks 5 and 6, they were only contained in the cattle crush for evaluation. On days 01, 07, 14, 21, 28, 35, and 42, blood samples were collected by jugular venepuncture in vacuum tubes without anticoagulants. Then, serum cortisol levels were measured using a radioimmunoassay. In the period of adaptation, during weeks 1 and 2, serum cortisol levels decreased in both the groups, with higher levels in the SS group; the same result was obtained in weeks 5 and 6. During treatment, however, there was a significant difference between the two groups in week 4, with a reduction in cortisol levels in the OT group. This result suggests a modulator effect of OT on neuroendocrine response to stress.
The embedded systems are present in the daily life of humans, from a simple microwave to a car of the years 2000. In recent years these systems have spread in Brazilian agriculture, such as irrigation control and animal feed control. Heat tolerance and adaptability to tropical environments are important factors to be considered in dairy cattle. The increase in the ambient temperature and, consequently, the heat stress causes a series of effects on the animal's metabolism that alter its behavior and well-being, directly affecting milk production. Surface temperature and respiratory rate are variables that can be used to identify heat stress by animals. Thus, a device, using the Arduino platform, it will be developed to measure the surface temperature and the respiratory rate of the animal, allowing a greater reliability in the information generated.
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