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The present study aimed to identify and describe cardiac alterations in sheep experimentally poisoned with Palicourea marcgravii through analysis of serum cardiac biomarkers (serum troponin I and creatine kinase - CK-MB) and electro and echocardiographic assessments to contribute to a better understanding of the poisoning pathophysiology. P. marcgravii is the main plant within a group of 22 species that cause sudden death in Brazil; its toxic principle is sodium monofluoroacetate. Eight healthy crossbreed male sheep, aged between five and twelve months, weighing 14 to 27kg, were evaluated. The animals received 1g kg-1 of P. marcgravii plants orally. The sheep were evaluated before administering the plant (T0) through electro and echocardiography and blood collection to assess cardiac biomarkers (CK-MB and cTnI). Collections and analyses were repeated every four hours until the animal’s death. During the study, there was the presence of extravasation of serum troponin I carried out in a qualitative test, with positive values at time T4, and the serum CK-MB biomarker had a peak at T4 and slightly decreased at T8. The electro and echocardiographic examinations showed that the cause of death in these animals was due to acute heart failure characterized by arrhythmias, tachycardia/ventricular fibrillation, drop in cardiac output, left ventricular (LV) systolic dysfunction by the progressive decrease in the LV ejection fraction (EF), decrease in LV fractional shortening (FS), and decrease in aortic flow velocity and aortic flow gradient. This study seems to be the first to evaluate cardiac alterations in sheep poisoned by P. marcgravii through cardiac biomarkers and electro and echocardiographic exams.

Background: Changes in glycemic levels can negatively affect the body. Several techniques for the measurement of blood glucose have been described, but the enzymatic method is considered standard and more accurate in both humans and animals. The College of American Pathologists recommends the use of portable glucometers (PGs), which are routinely used in human medicine because this is an easy, relatively inexpensive method that delivers results quickly. The aim of this study was to compare the results of the measurement of blood glucose in cattle obtained using portable Accu-Check® glucometer with the enzymatic method (EM), which is still considered standard.Materials, Methods & Results: Thirty crossbred cattle (Bos taurus), male and female, of different ages were evaluated. Through a puncture of the jugular vein, 10 mL of blood was collected, and one drop was immediately used in an Accu-Chek® PG; the remaining blood was stored in tubes containing sodium fluoride and tubes containing EDTA. The samples were packaged and sent to the laboratory for processing. Blood glucose was measured in the sodium fluoride samples using the enzymatic-colorimetric method (EM) employing Labtest® glucose kits with automatic ELISA spectrophotometer readings. The glycemic values obtained in this study with PG and EM ranged from 62 to 163.3 mg/dL. Mean glucose concentrations for the PG and EM methods were 93.53 mg/dL and 94.84 mg/dL, respectively, with no statistical difference (P > 0.05). The glycemia measurement results generated by both tests were normally distributed by the Shapiro–Wilk test (P > 0.05) and equal variances by the Levene test (P > 0.05). Discussion: The glycemic values obtained in this study meant that most of the mean glycemic values evaluated were >45 to 75 mg/dL, considered a reference for the species. This may have occurred due to the stress of handling during sample collection. Some authors compared the GP and EM methods and reported that the mean glucose concentrations obtained using PGs were significantly lower than those using the EM in both cattle and sheep and suggested using a correction factor for PGs. The error rates between PG and EM in our study ranged from 1.7 to 7.8%, much lower than the limits set by the Food and Drug Administration, which stipulates that PG cannot have error rates greater than 20% for blood glucose concentration. Comparison of PG and EM efficacy has been reported for dogs, cats, and horses, and significant differences were observed in the statistical analysis. In studies from other authors concluded that PG provides significantly different results from EM in the measurement of bovine and sheep blood glucose, but the final values can be corrected in order to obtain reliable results to be used in clinical practice. Hematocrit below 30% leads to erroneously high results, whereas hematocrit greater than 55% may give erroneously low results. However, failures are mainly caused by the user, such as improper application of the sample, excessive time to perform the exam, lack of equipment maintenance, and improper storage of test strips. PGs are becoming a very useful tool in the clinical practice with small animals, as studies have shown its reliability in relation to the EM, which is considered the gold standard. This practice may also be extended to cattle due to the reliability of PGs, as indicated in this study.

Background: The milk-feeding phase, wherein whole milk is the natural food, is critical to calf development, health, and vitality. However, feeding milk to calves is costly in the rearing system because the milk supplied to calves is not sold. In farms in which the average production is high, excess colostrum and transitional milk are produced that are used to feed calves until weaning. The objective of this study was to evaluate the performance of heifers exclusively fed colostrum (including transitional milk) or raw whole milk.Materials, Methods & Results: Immediately after their birth, 83 ear-tagged healthy Holstein Friesian heifers adequately receiving the initial colostrum were separated into two experimental groups. Group 1 (n = 34) was fed only fresh whole milk and group 2 (n = 49) was fed only colostrum diluted in water at a 2:1 ratio. Colostrum was removed from cows until the fifth day after birth and was stored in sanitized disposable plastic bottles, stored in a freezer at -20°C and before administration, the colostrum was thawed. Liquid diets were administered using a bottle twice a day during the first month, namely 2 L in the morning and 2 L in the afternoon. During the second month, the heifers were fed 4 L once a day in the morning. The heifers had access to an enclosure with fodder, in addition to concentrate specifically for heifers, which was placed in an individual trough daily. The leftovers were weighed at the end of the afternoon. The heifers were abruptly weaned when they reached a daily intake of 1 kg of concentrate. The heifers were individually weighed at birth and at 30, 60, 90, 120, 150, and 180 days. The average weights were 40.4, 54.1, 74.5, 95.1, 108.2, and 126.1 kg in group 1 and 45.4, 58.4, 78.2, 95.9, 110.8, and 125.1 kg in group 2. The use of diluted colostrum was satisfactory as it resulted in similar weight gains.Discussion: Feeding milk to calves is one of the most cost-increasing factors to a dairy farm because the total milk volume fed to animals at this stage is not sold and results in a large loss in income for the farmer. Calf management during the milk-feeding phase is of the utmost importance, especially in the first days after birth, to ensure the development of the systemic immune response of animals. The performance of these animals in the first months affects their subsequent development. Whole milk is commonly used to feed calves for 8 to 12 consecutive weeks. However, whole milk can be replaced by a good substitute, such as colostrum and transitional milk. The aim of this study was to show that these substitutes are effective alternatives for calf development and cost reduction. The weight gain of animals fed diluted colostrum was similar to that of animals fed only whole milk, which corroborates the results of previous studies on the development of calves treated with colostrum-based liquid diet, fermented or not, with and without additives. Those studies reported favorable growth rates in comparison with the traditional production system as a result of higher dietary protein levels in colostrum-based diets. The availability of roughages and concentrates should be initiated during the milk-feeding phase, as it is fundamental for rumen development, helps in early weaning and reduces expenses during this period. Replacing whole milk with colostrum and transitional milk for feeding calves, stimulating roughage, and concentrating intake can result in significant savings in the rearing system.

The aim of this report was to describe the clinical-pathological data of a case of clinical mastitis in a 20-day postpartum Holstein cow who presented udder edema and rupture of the ventral subcutaneous abdominal vein, and then died. This animal showed an increased volume of the left iliac fossa region, an increase in the size of the udder, and a marked decrease in milk production. Signs of parenchymal inflammation were observed during clinical examination. The screened mug test and California Mastitis Test (CMT) were then performed, and their results were negative. However, Staphylococcus aureus was isolated from milk and liquid collected by puncture from the ventrolateral region of the abdomen. Signs of bleeding and dehydration were found through blood counts and serum biochemistry. Soon after dying, the animal was submitted to necropsy, in which rupture of the mammary vein and intense inflammation with fibrin deposition and detachment of the subcutaneous tissue were observed. Histological examination revealed degeneration, diffuse necrosis, and thrombosis with areas of neovascularization associated with fibrin and cellular debris in the mammary vein.