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991.
992.
993.
The milk yields of 1824 cows were used to investigate the effect of lesion-specific causes of lameness, based on farmer treatment and diagnosis of lame cows, on milk yield. A three-level hierarchical model of repeated test day yields within cows within herds was used to investigate the impact of lesion-specific causes of lameness (sole ulcer, white line disease, digital dermatitis and other causes) on milk yield before and after treatment compared with unaffected cows. Cattle which developed sole ulcer (SU) and white line disease (WLD) were higher yielding cattle before they were diagnosed. Their milk production fell to below that of the mean of unaffected cows before diagnosis and remained low after diagnosis. In cattle which developed digital dermatitis (DD) there was no significant difference in milk yield before treatment and a slightly raised milk yield immediately after treatment. The estimated milk loss attributable to SU and WLD was approximately 570 and 370 kg, respectively. These results highlight that specific types of lameness vary by herds and within herds they are associated with higher yielding cattle. Consequently lesion-specific lameness reduction programmes targeting the cow and farm specific causes of lameness might be more effective than generic recommendations. They also highlight the importance of milk loss when estimating the economic impact of SU and WLD on the farms profitability.  相似文献   
994.
BACKGROUND: Fine needle aspiration (FNA) offers a rapid and minimally invasive means to distinguish malignant from benign neoplasms. However, few studies have been published regarding the cytopathology of mammary tumors in rats despite widespread use of the rat model for breast cancer formation and inhibition. OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of FNA cytology and to develop distinguishing cytologic criteria for the diagnosis of radiation-induced benign and malignant mammary tumors in rats. METHODS: In a study of radiation-induced mammary carcinogenesis, 100 Sprague-Dawley rats with cutaneous masses were randomly chosen for FNA. The aspirates were smeared, fixed, and stained with a modified Papanicolaou procedure for diagnostic evaluation. Cytologic and histologic diagnoses (benign vs malignant) were compared, and diagnostic accuracy was calculated using the histologic diagnosis as the criterion standard. FNA smears were scored semiquantitatively on a scale of 1-4 for cellularity, atypia, nuclear size, chromatin pattern, nuclear membrane thickness, nucleoli, and mitoses. The background was evaluated for necrosis, hemorrhage, inflammation, and mucosecretory material. Cytomorphologic features were compared statistically between benign and malignant tumors, based on the histologic diagnosis. RESULTS: The sensitivity of FNA was 92.3% and specificity was 89.4% for the detection of malignancy. However, 14% of specimens, all fibroadenomas by histology, had insufficient cells for cytologic evaluation, for an overall accuracy rate of 78.0%. Malignant tumors had significantly higher scores for all cytomorphologic features, and were significantly more likely to contain cell clusters and necrotic debris. CONCLUSIONS: FNA is an accurate method for differentiating benign and malignant rat mammary tumors.  相似文献   
995.
In this study,an alpine grassland in Henan County,Qinghai Province,in the source region of the Yellow River,was selected as the study area. The shear strength of root-soil composite system characteristics of 6 different plant combination types of grassland were explored by field investigation and sampling and indoor tests,which aimed to provide a theoretical basis for preventing and controlling soil erosion and shallow landslide caused by grassland degradation. The test results showed that the shear strength of root-soil composite system of 6 different combinations was a increasing trend with the decrease of altitude. Namely,the shear strength of the root-soil composite system of Stipa purpurea Griseb. + Kobresia pygmaea C. B. Clarke at the top of the sunny slope was 27.76 kPa and the value of Elymus nutans Griseb. at the bottom of the sunny slope was 37.53 kPa. The reasons why the shear strength of 6 kinds of combinations varied from large to small with the decrease of altitude were related to their density,moisture content,root content and dry weight of roots in the root-soil composite system samples. That is,the root content of composite system at the top,middle and bottom of the sunny slope were 6.2%,5.5% and 16.2%,respectively. The values at the top,middle and bottom of the shady slope were 8.0%,11.4% and 31.6%,respectively. © 2019 China Agricultural University. All rights reserved.  相似文献   
996.
Minimally invasive techniques used to evaluate canine peripheral lymphadenopathy (PLN), including fine needle aspiration biopsy with cytological evaluation (FNAB‐C) and flow cytometry (FC), have benefits and limitations. The cell block (CB) method is an alternate processing technique in which fine needle aspirate biopsy samples are concentrated, fixed, and embedded in paraffin for routine histological processing/staining. Utilizing three observers, we determined the diagnostic value of the CB in evaluating canine PLN across six categories (non‐diagnostic, reactive, inflammatory/infectious, probable lymphoma and lymphoma, metastatic neoplasia) and correlated findings to immunophenotypic and clonal antigen receptor rearrangement results in canine nodal lymphoma. Eighty‐five paired FNAB‐C and CB samples were evaluated from canine patients presenting to the University of Minnesota Veterinary Oncology or Internal Medicine services. Diagnostic quality samples were obtained in 55/85 (65%) CB and 81/85 (95%) FNAB‐C samples, respectively, and nodal pathology impacted CB diagnostic yield. Overall percent agreement between diagnostic‐quality FNAB‐C and CB samples was 86%, but increased to 95% if the categories of lymphoma and probable lymphoma were combined. There was 100% agreement for both the diagnoses of metastatic neoplasia and reactive lymph nodes and 92% agreement for the diagnosis of lymphoma/probable lymphoma. Using immunohistochemistry (IHC), CB samples correctly immunophenotyped 22/23 (96%) cases of B‐cell lymphoma, but only 1/6 (17%) cases of T‐cell lymphoma. IHC was not completed on nine cases of lymphoproliferative disease because of insufficient cellularity. When the CB method (CBM) yielded diagnostic quality samples there was good to excellent agreement with FNAB‐C samples and CB samples were suitable for some IHC tests.  相似文献   
997.
Neoplasms in the perianal region are frequently diagnosed in dogs. The aetiology is unknown, and most of them are benign. In this study, 240 neoplasms of the perianal glands of dogs were retrieved from the Department of Pathology archives of the Faculty of Veterinary Medicine and Zootechny of University of São Paulo (FMVZ/USP), from 1984 to 2004. All 240 cases were re‐examined by two pathologists. Nine cases (4%) were diagnosed as hyperplasia, 49 (20%) as group I adenoma, 81 (34%) were classified as moderately differentiated adenomas of the group II, 46 (19%) were poorly differentiated adenomas of group II, 48 (20%) were carcinoma of the group III according to the classification proposed by Berrocal, and 7 (13%) were other kind of tumours. Males over 8 years of age were predominantly affected. Cell proliferation was quantified by counting proliferating cell nuclear antigen (PCNA) positive nuclei, and apoptosis was quantified by counting fluorescent eosin‐stained apoptotic corpuscles (AC) in normal tissue, hyperplasia and in different histologic types of neoplasia of these glands. A parallel pattern of increase in both parameters (cell proliferation and apoptosis) was obtained. The net growth index (NGI), represents how much a cell population is proliferating or dying and was achieved by dividing the mean PCNA count in 1000 cells by the mean AC stain count in 1000 cells. NGI was different between hyperplasia and neoplasia; group I adenomas have a much higher potential of growth, and NGI decreases from benign towards malignant lesions. These results show up the importance of studying cell proliferation and apoptosis to understand the carcinogenesis of dog perianal gland.  相似文献   
998.
The aim of the study was to estimate nutritional and physiological consequences of combined supplementation of rat casein diets with a strongly oxidized mixture of fats and extract of polyphenols from chokeberry. The experiment was conducted on 80 young Wistar rats divided into 8 groups. The animals were fed diets supplemented with 8% of fresh or oxidized fats and 0.4, 0.8 and 1.2% of polyphenol extract together. Addition of the oxidized fats caused significant reduction in animal growth without a decrease in nitrogen digestibility. On the other hand, the extract of polyphenols suppressed nitrogen utilization; animal growth was however similar to the control group. Analysis of the variance showed negative influence of the oxidized fats on cholesterol and triacyloglycerol concentration in the blood of the experimental animals. Increased activity of both aminotransferases in the blood of rats fed diets containing the oxidized fats indicated on liver malfunction. There was no effect of the experimental factors on the antioxidant status of the blood, but a dose-dependent reduced content of malonylodialdehyde in the blood of rats fed diets supplemented with the extract of polyphenols suggested that the extract had a preventive effect against prooxidative activity of the oxidized fats.  相似文献   
999.
ABSTRACT

1. The aim of this study was to explore genetic diversity and possible origin of Bangladeshi (BD) native chickens. The complete mtDNA D-loop region was sequenced in 60 chickens representing five populations; naked neck, full feathered, Aseel, Hilly and autosomal dwarf. The 61 reference sequences representing different domestic chicken clades in China, India, Laos, Indonesia, Myanmar, and other Eurasian regions were included. The mtDNA D-loop sequence polymorphism and maternal origin of five BD populations were analysed.

2. A total of 35 polymorphic sites, and 21 haplotypes were detected in 60 mtDNA D-loop sequences. The haplotype and nucleotide diversity of the five populations were 0.921 ± 0.018 and 0.0061 ± 0.0019, respectively. Both mtDNA network and phylogenetic analysis indicated four clades (four haplogroups) in BD populations (21 haplotypes) along with 61 reference haplotypes. Clade E contained the most individuals (20) and haplotypes (11) of BD chickens, followed by clade D (17, 6), clade C (12, 2) and clade F (11, 2), respectively.

3. The higher number of unique haplotypes found in Yunnan, China, suggested that the origin of BD chickens was in this region. The haplotypes from different haplogroups were introduced in Bangladeshi chickens from India, China and Myanmar. The phylogenetic tree showed a close relationship of BD chickens with the clusters from India, China, Myanmar and Laos, and indicated the dispersion of BD chickens from these sources. The phylogenetic information revealed high genetic diversity of BD chickens because of their origin from different lineages with high genetic variation and distance, which was determined from four cluster and neighbour-joining trees.

4. In conclusion, BD populations had high genetic diversity. The mtDNA network profiles and phylogenetic trees showed multiple maternal origins of BD chickens from India, China, Myanmar and Laos.  相似文献   
1000.

Fifteen West African Dwarf grower bucks of about 6–8 months of age and average weights of 8.39 kg were used in a 70-day study to assess the intake and blood profile of West African Dwarf (WAD) goats fed diets containing graded levels of treated sweet orange peel meal (TSOPM), in a completely randomized design. Sweet orange peels were collected from sweet orange retailers within Makurdi, Benue State, Nigeria. The peels were packed into synthetic bags, compressed, and allowed to ferment for 12 h before sun-drying. The sun-dried peels were crushed into a meal and used to compound four treatments diets which consisted of 0, 60, and 80% TSOPM, designated diets A, B, and C respectively. Results showed that there were no significant differences (P?>?0.05) among the treatments in all the performance parameters except in the total forage intake values in which treatment A (19.74 kg) was significantly lower (P?<?0.05) than treatment B (21.77 kg) and treatment C (21.96 kg). But between treatment B and treatment C, there was no difference. Effect of treatments was also not apparent on the haematological indices measured, but the serum biochemical parameters showed significant difference (P?<?0.05) among the treatments for total protein values. The total protein value for treatment C (8.02 g/dl) was significantly higher (P?<?0.05) than treatments A (7.10 g/dl) and B (6.62 g/dl). The study showed that treated sweet orange peel meal can be used up to 80% level to replace maize offal in the diets of goats without adverse effects on the performance blood indices.

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