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71.
The object of the present study was to determine the influence of zeolite A, a calcium binder from the group of the aluminosilicate, on feed intake, macro and trace element metabolism as well as the milk yield in the following lactation in dairy cows. 46 cows were allotted to 2 groups (A--control group and B--experimental group). They were fed a total mixed ration (TMR) ad libitum 2 weeks before calving. Additionally the cows in group B received 90 g zeolite A/kg dry matter (DM). The individually feed intake was registered daily. The serum was analysed for Ca, Mg, and Pi (inorganic phosphate), Fe, FFA (free fatty acid) and beta-HB (hydroxybutyrate) and the plasma for the trace elements Cu, Zn, and Mn. After calving the milk yield (FCM) and the milk composition (fat, protein, lactose and urea) were analysed. Feed intake of group B, amounting to 6.2 +/- 1.3 kg DM/d was around 48% lower as compared to 12.0 +/- 1.4 kg DM/d for group A. The zeolite addition into the TMR showed a stabilizing effect on the average Ca concentration in the serum around calving. This effect led to a significantly lower Mg concentration on the day of calving and 1 day post partum. The Pi concentration was significantly lower already after the 1st week of zeolite supplementation and on the day of calving as compared to group A. There was no essential effect of zeolite A on the trace element concentration. The depression of feed intake for group B led to a significant increase of FFA one week after beginning zeolite supplementation and of beta-HB around calving. The feed intake post partum as well as the milk yield were not affected by zeolite supplementation. Because decreased feed intake of group B after zeolite supplementation and the occurred hypophosphatemia, it is not acceptable to use zeolite A in the proved dose for preventing milk fever.  相似文献   
72.
The medical records of 24 dogs with histologically confirmed mast cell tumors (MCT) of the muzzle were retrospectively evaluated to determine their biologic behavior and prognostic factors. Information on signalment, tumor grade and stage, treatment methods, and pattern of and time to failure and death was obtained from the medical record. Twenty-three dogs were treated with combinations of radiotherapy, surgery, and chemotherapy; 1 dog received no treatment. There were 2 Grade 1, 15 Grade 11, and 7 Grade III tumors. Tumors were stage 0 (n = 8), stage 1 (5), stage 2 (6), stage 3 (4), and stage 4 (1). Mean and median survival times of treated dogs were 36 and 30 months, respectively. Prognostic factors affecting survival time included tumor grade and presence of metastasis at diagnosis. Dogs with Grade I and II tumors survived longer than dogs with Grade III tumors. Variables, including sex, age, gross versus microscopic disease, and treatment type were not found to affect survival. Local control rate was 75% at 1 year and 50% at 3 years. Tumor grade was the only variable found to affect local control. Dogs with Grade I tumors had longer disease-free intervals than those with Grade II tumors, and dogs with Grade II tumors had longer disease-free intervals than dogs with Grade III tumors. Eight of 9 dogs dying of MCT had local or regional disease progression. Muzzle MCT a rebiologically aggressive tumors with higher regional metastatic rates than previously reported for MCT in other sites.  相似文献   
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Abstract – Downstream migration of female silver eel Anguilla anguilla (L.) was studied by remote telemetry in the lower part of the River Meuse (Belgium and the Netherlands) using a combination of nine detection stations and manual tracking. N = 31 eels (LT 64–90 cm) were implanted with active transponders and released in 2007 into the River Berwijn, a small Belgian tributary of the River Meuse, 326 km from the North Sea. From August 2007 till April 2008, 13 eels (42%) started their downstream migration and were detected at two or more stations. Mean migration speed was 0.62 m·s?1 (or 53 km·day?1). Only two eels (15%) arrived at the North Sea, the others being held up or killed at hydroelectric power stations, caught by fishermen or by predators or stopped their migration and settled in the river delta. A majority (58%) of the eels classified as potential migrants did not start their migration and settled in the River Berwijn or upper Meuse as verified by additional manual tracking.  相似文献   
74.
Chronic progressive lymphedema (CPL) is a debilitating condition identified in Clydesdales, Shires and Belgian draft horses and results in progressive swelling of the lower legs associated with the development of thick skin folds, ulcerations, fibrosis and marked hyperkeratosis. The result is severe discomfort and recurrent secondary infection, often requiring euthanasia. Due to the delayed onset, many horses are bred prior to diagnosis. CPL has only been documented in three related draft horse breeds, suggesting a genetic cause. Determining the molecular basis would enable owners to test horses prior to breeding and facilitate the elimination of CPL. Mutations in the FOXC2 gene cause a comparable condition in humans, lymphedema-distichiasis. This gene was sequenced in affected and unaffected draft horses and a control horse. Four single nucleotide polymorphisms (SNPs) were identified in unaffected draft horses and the control horse, indicating that they were not associated with CPL. A fifth SNP was seen in a single affected draft horse and the control horse. Since it was not seen in all affected draft horses, this SNP is not associated with the CPL phenotype.  相似文献   
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When avoparcin was prohibited for use as feed additive in poultry in Norway on 31 May 1995, an increased incidence of Clostridium perfringens-associated necrotic enteritis (NE) and an increase in the use of antibacterial (AB) drug therapy in meat-type poultry was expected. The consumption of AB drugs for use against NE in poultry in the period 1990-2001 was investigated by use of sales statistics at the drug-wholesaler level. Defined daily dose (DDD) per kg live weight poultry was the unit of measurement for drug use (to correct for differences in the dosages). Sales figures of the AB drugs were converted to number of DDDpoultry sold for the numbers of broilers at risk (broilers were 97% of the slaughter poultry). Estimated annual percentages of the broilers treated against NE increased abruptly after the avoparcin ban--but in 1996, this figure declined to the same level as before the ban and has remained at that low level since then. In November 1995, narasin was approved temporarily as an ionophore feed additive (IFA) in broilers. The usage patterns of IFAs in broilers were measured as the weight of feed to which an IFA was added per broiler chicken produced. In 1996-2001, the IFAs used in broilers were predominantly narasin. We note that the temporary increase in NE after the avoparcin ban coincide with the period before narasin became available. The increase in the consumption of AB drugs for the treatment of NE in poultry following the avoparcin ban has been negligible.  相似文献   
77.
Although recognized as a possible complication to sepsis, there are few published reports on brain abscesses in foals. This case report describes a 4-month-old Icelandic filly that, as a neonate, had a history of pyrexia and lameness, which resolved with antibiotic treatment. Approximately 3 months later, the foal developed neurological signs which were initially attributed to trauma; she was referred for further investigation. The clinical signs were consistent with a lesion of the right forebrain. Computed tomography examination revealed a mass, approximately 6 cm in diameter, located in the right cerebral hemisphere craniolateral to the right lateral ventricle. Because of the poor prognosis, the foal was killed, and a postmortem was performed. The findings confirmed the presence of an abscess of the right cerebral hemisphere, leading to severe atrophy of the cortex and dilation of both lateral ventricles. The left hemisphere was moderate-to-severe atrophic and had displaced to the left. Streptococcus equi subspecies zooepidemicus was isolated in pure culture from the abscess. The clinical features of the foal were compared with the pathological findings.  相似文献   
78.
Increasing emphasis is being placed on the role of fibroblast growth factors (FGFs) in hair follicle cycling. In mice, expression of FGF18 mRNA peaks during the late telogen phase, leading to the hypothesis that FGF plays a role in anagen induction. There are no data on the presence of FGF18 in dogs. The main objective of this study was to identify and locate FGF18 in the canine hair follicle. The second objective was to assess potential differences in FGF18 concentration between biopsies taken in winter and summer, shoulder and flank regions, and between different sexes. Skin tissue from 10 healthy beagle dogs (three intact females, three spayed females and four intact males) was collected from the shoulder and flank. The biopsies were collected in February and August on day 0, after which the dogs were clipped and biopsies collected again from the shoulder and flank on days 1, 3, 7 and 17. Paraffin sections (4 μm thick) of the biopsies were stained with an anti-FGF18 antibody. The FGF18-positive cells were counted in the hair follicle epithelium from seven follicular units of each biopsy. Fibroblast growth factor 18 was detected as granular cytoplasmatic staining in follicles at the level of the inner root sheath, and rarely in the outer root sheath and dermal papilla. It was also detected in the apocrine glands, in arrector pili muscles and in vascular endothelial cells. There was no statistical difference in the number of FGF18-positive cells or follicles between sexes, different anatomical locations, seasons or the consecutive days of sampling.  相似文献   
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