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71.
A 2-year-old Dachshund was presented for vomiting and diarrhea. Abdominal ultrasound revealed Dirofilaria immitis in the abdominal aorta and an avascular segment of small intestine. The dog was euthanized. Necropsy revealed D. immitis in the abdominal aorta and widespread necrotizing arteriolitis. This is a unique presentation of aberrant migration of D. immitis.  相似文献   
72.
The aim of this study was to develop regression models for correlation of canine fetal heart development with body size to characterize normal development or suggest cardiac anomalies. Twenty clinically healthy pregnant bitches, either brachycephalic and non-brachycephalic, were examined ultrasonographically. Transabdominal fetal echocardiography was conducted every 4 days from the beginning of cardiac chambers differentiation until parturition. Ten cardiac parameters were measured: length, width and diameter of the heart; heart area; left and right ventricular dimensions; left and right atrial dimensions; and aortic and pulmonary artery diameter. Femoral length, biparietal diameter and abdominal cross-sectional area were also recorded. Regression equations were developed for each parameter of fetal body size, and linear and logarithmic models were compared. The model with the highest correlation coefficient was chosen to produce equations to calculate relative dimensions based on the correlations. Only the left-ventricular chamber differed between the two racial groups. Biparietal diameter was the independent parameter that produced the highest correlation coefficient for the most fetal cardiac dimensions, although good correlations were also observed using femoral length and abdominal cross-sectional area. Heart width and heart diameter were used as surrogates of cardiac development, as these measurements showed the best statistical correlation. Quantitative evaluation of fetal cardiac structures can be used to monitor normal and abnormal cardiac development.  相似文献   
73.
Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate.  相似文献   
74.
75.

Background

The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined and many variations between experimental animal models and spontaneous disease exist.

Objectives

The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings.

Methods

Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation.

Results

CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction.

Conclusions

Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans.
  相似文献   
76.
The aim of this study was to characterize preferences of farmers for breeding goal traits with Danish Red (DR) or Danish Jersey (DJ) cows. A breed-specific survey was established to characterize farmers’ preferences for improvements in 10 traits, by means of pairwise rankings using the online software 1000Minds. These pairwise rankings were based on equal economic worth of trait improvements. The DR survey was filled in by 87 farmers and the DJ survey by 76 farmers. Both DR and DJ farmers gave the highest preference to improvements in mastitis, and the lowest to calving difficulty. By means of a cluster analysis, three distinct clusters of farmers were identified per breed. Comparisons of herd characteristics between clusters suggest that farmers choose to improve traits that are problematic in their herds. This study shows that heterogeneity exists in farmers’ preferences for trait improvements and that herd characteristics influence these preferences in DR and DJ.  相似文献   
77.
OBJECTIVE: To describe the vascular supply to a facial skin flap based at the commissure of the lip in the dog and report on its use in four dogs. STUDY DESIGN: Experimental and prospective clinical study. Animals Five canine cadavers and four client-owned dogs. METHODS: In the cadavers, the ventral aspect of the zygomatic arch, the ventral margin of the caudal mandible and the wing of the atlas were marked as anatomical boundaries of a skin flap that was elevated from the subcutaneous tissues to the level of the medial canthus of the eye. Methylene blue dye and barium sulphate solution were independently infused through a common carotid (three dogs) or facial artery (two dogs) catheter. Distribution of dye throughout the harvested skin was assessed subjectively. After contrast infusion the flap was excised and radiographed. The technique was used to reconstruct large facial or nasal defects in four dogs after tumour or skin lesion excision. RESULTS: Cadaver dissections and contrast studies clearly demonstrated three direct cutaneous arteries, the superior and inferior labial arteries and the angularis oris artery, arborising within the base of the flap. A separate direct cutaneous branch of the angularis oris artery was identified. An arterial plexus was identified within the distal flap, within which this artery communicates with the transverse facial artery and a cutaneous branch of the masseteric artery. Dye infusion caused discolouration of the elevated skin and vasculature within the flap. The flap survived in all clinical cases with marginal distal necrosis in one dog. CONCLUSIONS: The complex facial flap described is perfused by three direct cutaneous arteries and functions reliably in clinical cases.  相似文献   
78.
The objective of this study was to investigate epidemiological risk factors for porcine non-specific colitis (NSC). Forty-seven Scottish pig farms, with and without a clinical history of diarrhoea during the growing period (15-40 kg), were selected. The study included farm visits, clinical inspection of pigs, completion of farm management questionnaires, pathological tests into the cause of the diarrhoea and analysis of the non-starch polysaccharide (NSP) content of feeds. The results from 17 farms designated as NSC and 10 control farms suggest dietary associations with NSC. Farms with NSC fed diets with significantly higher levels of NSPs, especially containing the sugars glucose, arabinose and xylose. Few management factors were identified, although the high prevalence of infectious colitis reduced the power of the study.  相似文献   
79.
80.

Background

In Kenya, rice (Oryza sativa L.) is mainly produced under irrigation by small-scale farmers. Mwea irrigation scheme (MIS) in Kirinyaga County accounts for 80–88% of rice production. Here, rice is the main source of livelihood and a source of revenue generation for the county. However, a recently established invasive freshwater snail, Pomacea canaliculata (Lamarck) (family: Ampullariidae), a species of apple snail, presents a serious threat to rice production.

Results

Household surveys, focus group discussions and key informant interviews highlight apple snail as a serious problem in MIS. Households that observed at least a moderate level of infestation (>20% of cultivated area) experienced significant reductions in rice yield (~14%) and net rice income (~60%). Farmers reported increased use of chemical pesticides for management of apple snail. In addition, the cost of hired labor for physical removal of egg masses and snails is resulting in substantial negative effects on net income. Farmer age, area of land owned, responsibility for decision-making, receipt of extension advice, training, and membership of a farmer organization, were all statistically significant variables to explain farmers awareness of the need for area-wide apple snail management.

Conclusion

Strategies to limit the spread of apple snail are urgently needed. A Multi-Institutional Technical Team (MITT) has been established to spearhead management efforts and consolidate advice to farmers on how to manage apple snail. However, without action to mitigate spread, the consequences could be disastrous for rice production and food security in Kenya, and for other rice growing regions across Africa. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
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