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Endozoochory is known as an important mechanism for the spread of weeds. We carried out experiments to assess the fate of seeds of several weed species (Convolvulus arvensis, Cuscuta campestris, Rumex crispus, Hordeum spontaneum and Sorghum halepense) after passing through the gut of sheep and goat. Eighteen animals of both sheep and goat received diet mixed with seeds of the weed species or control with only wheat bran (five weed species + control × three replications). Results showed that a higher proportion of seeds were missing after passage through the sheep gut than in goats. In goats, a greater proportion of seeds were dead after passage, but the number of seeds collected from dung was also greater. Weed species differed, with the highest seed recovery and viability in Cuscuta campestris. Based on time of seed passages through the animal gut estimated for the different weed species, we recommend that sheep should be kept in a corral for 96 hr to minimise seed transportation via their faeces. For goats, if R. crispus and C. arvensis seeds could be excluded from the diet, then maintaining them for 96 hr in an animal stall would ensure little seed transportation via dung, but we found R. crispus and C. arvensis seeds to be present and viable in goat dung even 120 hr after feeding. Very large numbers of viable seeds can be found in goat and sheep dung, so the use of rotted manure is highly recommended to avoid transportation of viable seeds via manure fertilisers.  相似文献   
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The waxy character is achieved in durum wheat (Triticum turgidum L. var. durum) when the granule‐bound starch synthase activity is eliminated. The result is a crop that produces kernels with no amylose in the starch. The presence of two Waxy loci in tetraploid wheat permits the production of two partial waxy wheat genotypes. Advanced full and partial waxy durum wheat genotypes were used to study the effect of waxy null alleles on pasta quality. Semolina from full and partial waxy durum wheats was processed into spaghetti with a semicommercial‐scale extruder, and pasta quality was evaluated. Cooked waxy pasta was softer and exhibited more cooking loss than pasta made from traditional durum cultivars. These features were attributed to lower setback of waxy starch as measured with the Rapid Visco Analyser. High cooking loss may be due to the lack of amylose‐protein interaction, preventing the formation of a strong protein network and permitting exudates to escape. Waxy pasta cooked faster but was less resistant to overcooking than normal pasta. Partial waxy pasta properties were similar to results obtained from wild‐type pasta. This indicates that the presence of a single pair of functional waxy genes in durum wheat was sufficient to generate durum grain with normal properties for pasta production. Waxy durum wheat is not suitable for pasta production because of its softening effect. However, this property may offer an advantage in other applications.  相似文献   
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OBJECTIVE: To assess the safety of endoscopic retrograde pancreatography (ERP) in dogs by performing repeated clinical examinations and laboratory analyses of serum amylase, lipase, canine trypsin-like immunoreactivity (cTLI), and canine pancreatic elastase 1 (cE1) after the procedure. ANIMALS: 7 healthy Beagles. PROCEDURES: Clinical examinations were performed and blood samples obtained for serum enzyme determinations before and at intervals (10 minutes; 2, 4, and 6 hours; and 1, 2, and 3 days) after ERP. RESULTS: Repeated clinical examinations revealed no signs of ERP-induced complications in the 7 dogs. Results of repeated laboratory tests indicated a transient increase in serum values of amylase, lipase, and cTLI but not cE1. Mean +/- SD lipase activity increased from 120.7 +/- 116.4 U/L to 423.4 +/- 243.1 U/L at 4 hours after ERP. Median serum cTLI concentration increased from 16.2 microg/L (range, 77 to 26.5 microg/L) to 34.9 microg/L (range, 16.6 to 68.3 microg/L) 10 minutes after ERP. Enzyme values returned to baseline levels at the latest on day 2 in 6 of 7 dogs. Highest values for serum amylase, lipase, and cTLI and their delayed return to baseline values were detected in 1 dog with contrast filling of the pancreatic parenchyma. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that ERP appears to be a safe imaging technique of pancreatic ducts in healthy dogs, although it induced a transient increase in serum values of pancreatic enzymes. In dogs, repeated clinical examinations and serum enzyme determinations can be used to monitor ERP-induced complications such as acute pancreatitis.  相似文献   
55.
Peripheral blood smears (stained with May-Griinwald-Giemsa) taken from 250 dogs showing clinical signs suggestive of ehrlichiosis were examined for the presence of inclusion bodies or morulae of Ehrlichia canis. Inclusion bodies were seen in 220 (88 per cent) cases, of which only 9 (4 per cent) cases exhibited morulae. Thus inclusions other than morulae may play an important role in the diagnosis of canine ehrlichiosis in enzootic areas.  相似文献   
56.
Endothelial dysfunction contributes to the development of ungulate's laminitis. Although extensively studied in equines, the endothelial function is not fully examined in bovine digital veins (BDVs). BDVs were studied under isometric conditions to describe the acetylcholine (ACh) endothelium‐dependent relaxation. Concentration–response curves were constructed to phenylephrine, ACh, and sodium nitroprusside (SNP). Relaxation responses were evaluated using either phenylephrine or depolarizing high‐potassium Krebs solution (DKS) as precontraction agents. Endothelium denudation and incubation with L‐NAME (300 μM), indomethacin (10 μM) or both were used to explore endothelial‐mediated mechanisms. Endothelium denudation did not modify phenylephrine and SNP responses, however, significantly (p < 0.05) converted a relaxation (63.2 ± 5%) response to ACh into a contraction (30.3±9%). The ACh‐evoked relaxation was significantly (p < 0.05) reduced in the presence of indomethacin (37.5 ± 6%) and L‐NAME (6.40 ± 2%). The presence of both inhibitors abolished the ACh‐evoked relaxation. Although DKS caused a higher precontraction than phenylephrine, ACh‐evoked relaxation (22.4 ± 3.4%) was still observed and was reduced by the combination of inhibitors (7.0 ± 1.0%). The ACh endothelium‐dependent relaxation in BDVs is essentially mediated by nitric oxide and endothelium‐derived prostanoids. The BDV endothelium function is a dynamic component in the control of the bovine digital blood flow, particularly under endothelial dysfunction conditions when venoconstriction might lead to postcapillary resistance increase.  相似文献   
57.
Lameness is a growing concern to the dairy industry worldwide. However, little is known about lameness and its causes in grazing cattle, especially in tropical climates. This study aimed to assess the prevalence of hoof lesions and lameness in dairy herds of all year-round grazing cattle under tropical condition, and to identify the main lesions associated with lameness. We visited 48 farms located in the Minas Gerais state, Brazil, equally divided into four groups based on daily milk production. All lactating cows in the visited farms were locomotion scored, and a representative sample was randomly chosen for hoof inspection. Among the 2267 lactating cows evaluated, 16% were scored as lame and 7% as severely lame. Nearly all cows presented at least one type of hoof lesion, of which heel horn erosion (90%), white line fissure (50%), and digital dermatitis (33%) were the most prevalent. Heel horn erosion was present in all farms and digital dermatitis was present in 96% of the farms. Sole ulcer was observed in a single animal. Additionally, digital dermatitis and white line fissure were correlated to a 2.5 times increase in the odds of a poor mobility score. Collectively, our results demonstrate that digital dermatitis and white line fissure are the main concern and the biggest cause of lameness in grazing cattle under tropical conditions.  相似文献   
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Fourteen dogs had shown chronic or intermittent diarrhea for more than 1 year. Diarrhea had been successfully treated with tylosin for at least 6 months but recurred when treatment was withdrawn on at least 2 occasions. Tylosin-responsive diarrhea (TRD) affects typically middle-aged, large-breed dogs and clinical signs indicate that TRD affects both the small and large intestine. Treatment with tylosin eliminated diarrhea in all dogs within 3 days and in most dogs within 24 hours. Tylosin administration controlled diarrhea in all dogs, but after it was discontinued, diarrhea reappeared in 12 (85.7%) of 14 dogs within 30 days. Prednisone given for 3 days did not completely resolve diarrhea. Probiotic Lactobacillus rhamnosus GG did not prevent the relapse of diarrhea in any of 9 dogs so treated. The etiology of TRD, a likely form of antibiotic-responsive diarrhea (ARD) is unclear. The following reasons for chronic diarrhea were excluded or found to be unlikely: parasites, exocrine pancreatic insufficiency, inflammatory bowel disease, small intestinal bacterial overgrowth, enteropathogenic bacteria (Salmonella spp., Campylobacter spp., Yersinia spp., or Lawsoni intracellularis), and Clostridium perfringens enterotoxin and Clostridium difficile A toxin. A possible etiologic factor is a specific enteropathogenic organism that is a common resident in the canine gastrointestinal tract and is sensitive to tylosin but difficult to eradicate. Additional studies are required to identify the specific cause of TRD.  相似文献   
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