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161.
The practice of covering in herds is often used in Crioulo breeding farms, thus not allowing the determination of ovulation dates and the early detection of pregnancies. This fact complicates the estimation of gestational age after 70 days of conception. This study aimed to evaluate the diameter of the fetal orbits of Crioulo mares to develop a formula to estimate a gestational date. Measurements of 164 fetal ocular orbits were performed in 124 Crioulo mares with gestational ages ranging between 119 and 341 days. The current study observed a linear growth pattern of Crioulo fetal orbits up to 341 days of gestation. Thus, obtaining a suitable linear regression model to determine the gestational age of Crioulo mares based on fetal ocular orbit diameter measure is possible. The obtained model was y = 8.3756x + 11.90, where y represents the gestational age in days, and x represents the diameter of the fetal ocular orbit in millimeters. This formula had an r2 of 0.985 (P < .001). We conclude that this model allows researchers and veterinarians to accurately estimate the gestational age of Crioulo mares between 4 and 11 months of pregnancy.  相似文献   
162.
An outbreak of mycoplasmosis caused by Mycoplasma alligatoris resulted in the death or euthanasia of 60 American alligators (Alligator mississippiensis) from a population of 74 captive bull alligators in Florida in 1995. The natural reservoir, routes of transmission, and host range of M. alligatoris are unknown. This study was undertaken to determine whether crocodilian species other than American alligators are susceptible to M. alligatoris. Six broad-nosed caimans (Caiman latirostris) and six Siamese crocodiles (Crocodylus siamensis) were experimentally inoculated with 10(6) colony forming units (CFU) of M. alligatoris instilled through the glottis. Two caimans and two crocodiles were used as negative controls. Six and four American alligators were used as positive and negative controls, respectively. Three of six (50%) inoculated caimans died within 10 wk postinoculation (PI) of severe mycoplasmosis. Gross necropsy, histopathologic, and culture results were similar for broad-nosed caimans and American alligators. None of the inoculated Siamese crocodiles developed mycoplasmosis, though M. alligatoris was isolated from the tonsils in three of six (50%) animals at necropsy. All the inoculated crocodilians that survived showed significant seroconversion by 6-8-wk PI (P < 0.05). The infective dose 50% (ID50) and lethal dose 50% (LD50) of M. alligatoris for the broad-nosed caiman are 10(6) CFU when instilled through the glottis, which is similar to that of the American alligator. Although the host range of M. alligatoris is not restricted to the American alligator, the organism does not appear to be pathogenic for Siamese crocodiles. Other species of crocodilians may be susceptible to infection with M. alligatoris, and this organism should be considered when the rapid onset of clinical signs of pneumonia, polyarthritis, pericarditis, and death occur.  相似文献   
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Three experiments were carried out to determine the crude protein requirements for maintenance (CPm) and weight gain (CPg) of meat quail and to develop protein‐requirement prediction models. Experiment 1 was conducted to determine CPm by the nitrogen‐balance technique. The regression of nitrogen balance on nitrogen intake revealed a CPm requirement of 2.94 g/kg0.75/day. Experiment 2 was aimed at determining CPm by the comparative‐slaughter technique. Retained nitrogen (RN) and nitrogen intake (NI) were quantified considering the metabolic weight of the birds. The linear regression of RN on NI provided a CPm estimate of 6.63 g/kg0.75/day. Experiment 3 was conducted to determine CPg. The regression of body nitrogen from the carcasses on fasted body weight revealed CPg estimates of 407.68 (0–7 days), 501.76 (8–14 days), 470.40 (0–14 days), 517.44 (15–21 days), 627.20 (22–28 days), 423.36 (29–35 days), and 517.44 mg/g (15–35 days). The protein‐requirement prediction models developed for meat quail aged 0–7, 8–14, 0–14, 15–21, 22–28, 29–35, and 15–35 days were CP = 2.94.W0.75 + 0.408.G; CP = 2.94.W0.75 + 0.502.G; CP = 2.94.W0.75 + 0.470.G; CP = 2.94.W0.75 + 0,517.G; CP = 2.94.W0.75 + 0.627.G; CP = 2.94.W0.75 + 0.423.G; CP = 2.94.W0.75 + 0.517.G, respectively, where: W0.75 =  metabolic weight (kg), and G =  daily weight gain (g).  相似文献   
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An agrarian sensorial system based on temperature, moisture, and all solid-state ion-selective potentiometric sensors was developed with the objective of monitoring the behavior of H+ and Ca2+ ions in soil and in real conditions, contributing with a new tool that tries to complement the current precision agriculture technology. The evaluation of the sensorial system to pH monitoring presented a good correlation between the results obtained by the system and the standard methodology, allowing us to notice the soil buffer capacity at different soil depths. With regard to calcium, the sensor system also presented an agreement between its results and those obtained by flame atomic absorption spectrometry, using a calibration model based on multiple linear regressions that allows the correct determination of Ca2+ concentrations in soil depths where the relative moisture is different. In this way, using well-known potentiometric sensors in a complex, discontinued, and heterogeneous matrix, such as soil, the sensorial system proved to be a useful task for agrochemical field applications.  相似文献   
168.
The objective of this study was to evaluate the electrocardiographic alterations in the cardiac rhythm in dogs treated with levamisole hydrochloride over a period of 24 hours. Thirty-six mixed-breed dogs, both male and female, all clinically healthy, were used in the experiment. The dogs were divided into 6 groups with 6 dogs in each group, according to dosage and route of administration. The Holter test was initiated immediately after the treatment, and was maintained for 24 hours. In the group treated with 10 mg/kg by way of subcutaneous injection, one of them showed ventricular premature complexes, sometimes isolated and other times in pairs, and ventricular tachycardia, concentrated mainly in the first hour after administration of the drug. In the group of 6 animals treated subcutaneously with 25mg/kg, four showed isolated ventricular premature complexes, ventricular bigeminy and trigeminy, mainly during the first 2 hours after administration of the drug. All the animals in the other groups showed sinus arrhythmia followed by sinus arrest. The disturbances in the cardiac rhythm observed in clinically healthy animals treated with levamisole hydrochloride, indicate that it is preferable to avoid subcutaneous administration of levamisole hydrochloride and that the oral administration of the drug should be done with caution.  相似文献   
169.
Like edge effects, variations in topography can influence the physiognomy and structural patterns of the vegetation due to the high dynamics encountered in inclined areas. We evaluated the effect of edges on the structure and physiognomy of the arboreal and woody understory communities in patches of an Atlantic Forest remnant in two distinct topographic positions. Four study situations were laid out (slope edge, top edge, slope interior, and top interior), with ten 10 × 10 m plots each to sample the arboreal components (circumference at breast height ≥15 cm), and ten 5 × 5 m plots (in the corner of each arboreal component plot) to sample the woody understory (circumference at ground level ≥3 cm and with circumference at breast height <15 cm). We investigated physiognomic and structural variables of edge and interior environments in similar topographic positions on both slope and top (level) areas of the same remnant forest. Physiognomic and structural differences between edge and interior vegetation were noted, and these were found to be still more evident when different topographic positions were considered. Physiognomic and structural variations between the edge and interior vegetation were more notable on slopes than on hill tops, indicating greater dynamics in areas with greater topographic inclinations.  相似文献   
170.
The present study assesses the oxidative burst activity from polymorphonuclear leukocytes (PMNLs) from bovine leukemia virus (BLV)-infected cows. Fifteen clinically healthy cows were divided into serologically positive cows without any hematological alteration, serologically positive animals with persistent lymphocytosis (PL) and healthy serologically negative cows. The oxidative burst activity from the PMNLs was evaluated by flow cytometry using 2',7'-dichlorofluorescein diacetate as a probe. PMNLs from each cow were incubated with heat-killed Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) to stimulate oxidative burst activity. The results of the present work showed no significant difference in the oxidative burst activity without any stimulus and elicited by S. aureus. Conversely, a decrease in the oxidative burst index induced by E. coli in PMNLs was observed in BLV-infected cows.  相似文献   
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