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101.
Abstract

Extract

In the course of some earlier experiments, it was observed that vitamin B12 deficiency in 2 hoggets was corrected by injection of hydroxocobalamin (vitamin B12b) (E. D. Andrews, pers. comm., 1972). Since this form of therapy offered a convenient and effective means of treating young lambs suffering from vitamin B12 deficiency, more detailed investigations were desirable. It has been known for some time that lambs on the cobalt-deficient area at the Ministry of Agriculture and Fisheries Kaitoke Farm lose condition after weaning. Abnormal amounts of methylmalonic acid (MMA) had been found in the urine of some of these lambs, indicating a state of vitamin B12 deficiency Andrews et al, (1970 Andrews, E. D., Hogan, K. G., Stephenson, B. J., White, D. A. and Elliott, D. C. 1970. Cobalt and thiabendazole live-weight responses in grazing sheep, and their relation to the urinary excretion of methylmalonic acid. N.Z. Jl agric. Res., 13: 950965. [Taylor &; Francis Online], [Web of Science ®] [Google Scholar]).  相似文献   
102.
103.
Gram-negative bacteria that commonly cause bovine mastitis are classified as environmental pathogens. The point sources of coliform bacteria that cause infections include bedding materials, soil, manure and other organic matter in the environment of cows. Rates of coliform mastitis increase during climatic periods that maximize populations in the environment. The portal of entry into the mammary gland for Gram-negative bacteria is the teat canal. Once in the gland, bacteria must utilize available substrates in the mammary secretion to replicate and evade host defenses. Rates of coliform mastitis are greater during the transitional phases of the non- lactating period than during lactation. The ability to infect the non-lactating gland is directly related to the ability of bacteria to acquire iron from the mammary secretion. The primary host defense against coliform mastitis during lactation is the elimination of bacteria by neutrophils migrating into the gland in response to inflammation. Damage to the host is mediated by the release of endotoxin. The severity and duration of clinical signs associated with coliform mastitis are reduced by the use of core-antigen bacterins.  相似文献   
104.
Atrial septal defect, while rare in dogs, can result in severe clinical signs. Surgical correction of atrial septal defect requires open-heart surgery. Transcatheter closure techniques provide minimally invasive surgical alternatives.  相似文献   
105.
Kennebec potatoes were evaluated for the effect of storage temperature and time on tuber composition and on mealiness as measured by extrusion force of baked potato and Brabender viscosity of raw, lyophilized tissue. Potatoes from three specific gravity classes, 1.072, 1.082, and 1.090 (±0.001), were evaluated initially and after storage at 1.7°C for 2 and 3 mo., 7.2°C for 2 and 3 mo., 1.7°C for 2 mo. followed by 7.2°C for 1 mo., and 7.2°C for 2 mo. followed by 1.7°C for 1 mo. There were highly significant differences in mealiness associated with the storage treatments and with specific gravity. Mealiness decreased as temperature decreased. Mealiness estimates of tubers from the storage temperature reversal treatments were intermediate to those of the 7.2°C and 1.7°C treated tubers. Simple correlation analysis showed extrusion force and Brabender viscosity to be significantly and positively related to each other, to total starch and to swollen starch and significantly but inversely related to glucose and to the sum of glucose plus sucrose. Specific gravity and total solids were significantly but less highly positively correlated with both physical measurements. Multiple correlation-regression analysis showed only total starch to be significantly related to mealiness independent of the other compositional variables.  相似文献   
106.
Increasing antimicrobial resistance has become a serious concern worldwide and antimicrobial use in animal agriculture is currently under scrutiny. Mastitis is the most common reason for antibiotic use in dairy herds and thus, antimicrobial resistance of mastitis pathogens has received recent attention. The purpose of this study was to describe and compare antimicrobial susceptibility of mastitis pathogens isolated at calving from first lactation and older cows. A total of 202 bacteria were isolated from intramammary infections (IMIs) within 3 days after calving over a 16-month study period in the Krauss Dairy Research Herd at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, OH. Of these IMIs, 78% were caused by coagulase-negative staphylococci (CNS). Forty-four percent of them were resistant to at least one antibiotic. Most resistance was observed against penicillin, 39% of the isolates from older cows and 26% from first lactation cows being resistant to penicillin (P > 0.05). Also MIC90 for penicillin was higher among isolates from older cows. On the other hand, resistance to tetracycline was more common and MIC90 higher among isolates from first lactation cows than from older cows. Differences in the proportions of resistant isolates between first lactation and older cows were not statistically significant, though. The resistance patterns of the CNS isolated during the study are concordant with antimicrobial usage in the study herd. This is in agreement with the generally accepted notion that selection pressure from the use of antibiotics is a main factor in development of antibiotic resistance.  相似文献   
107.
OBJECTIVE: To determine whether ticlopidine exerts an antiplatelet effect, estimate the pharmacodynamics of ticlopidine, and evaluate any acute adverse effects associated with administration of ticlopidine in cats. ANIMALS: 8 domestic purpose-bred sexually intact male cats. PROCEDURE: Ticlopidine was administered orally (50 mg, q 24 h; 100 mg, q 24 h; 200 mg, q 24 h; and 250 mg, q 12 h). Each treatment period consisted of 10 days of drug administration. Platelet aggregation studies with adenosine diphosphate (ADP) and collagen and evaluation of oral mucosal bleeding times (OMBTs) were performed on days 3, 7, and 10 during each drug administration. Serotonin was measured to evaluate secretion at baseline and on day 10 for cats that received the 250-mg dosage. RESULTS: A significant reduction in platelet aggregation was detected in response to ADP on days 7 and 10 at 100 mg, on day 3 at 200 mg, and on days 3, 7, and 10 at 250 mg. A significant increase in the OMBT and decrease in serotonin release on day 10 at 250 mg was also detected; however, the cats had anorexia and vomiting at the 250-mg dosage. CONCLUSIONS AND CLINICAL RELEVANCE: Although there was a consistent antiplatelet effect at the 250-mg dosage, there was dose-dependent anorexia and vomiting that we conclude precludes the clinical usefulness of this drug in cats.  相似文献   
108.
109.
Calculations have been made to determine the effects of variations in the extreme ultraviolet solar radiation on the upper atmospheres of mars and Venus. The results indicate that the exospheric temperature from 300 degrees K to 600 degrees K during the solar cycle, with a corresponding range on Venus of 450 degrees K to 850 degrees K. At the present time, the temperature of the Martain exosphere should be approximately 500 degrees K.  相似文献   
110.
Twenty‐six per cent of Mongolians live pastoral lifestyles, increasing their likelihood of exposure to ticks and placing them at a higher risk for contracting tick‐borne diseases (TBDs). Anaplasma spp. and Rickettsia spp. have been identified in ticks, livestock and humans in Mongolia, but no known qualitative research has been conducted investigating the association between nomadic herder characteristics, tick bite history and exposure to TBDs. To better understand the association between self‐reported tick bites and symptoms versus actual exposure to TBDs, this study paired serological data with 335 surveys administered to Mongolian herders, ages 12–69, from 2014 to 2015. Logistic regression results identified no significant associations between reported tick bites or symptoms with serological evidence of Anaplasma spp. and Rickettsia spp. controlling for age, gender and aimag. Among the 335 respondents who were seropositive to either Anaplasma spp. or Rickettsia spp., 32.9% self‐reported experiencing abnormal symptoms such as redness, inflammation, headache, arthritis or fever after being bitten. Alternatively, 17.3% (58/335) of individuals reported experiencing symptoms following a tick bite in instances where serological results indicated no exposure to Anaplasma spp. or Rickettsia spp. Results also identified inconsistencies in reporting and seroprevalence among different age groups, with children having the highest reporting and treatment seeking rates but low levels of exposure in comparison with other groups. While survey results showed that individuals were aware of peak tick seasons and tick species that inhabit specific areas, 58% of heads of households (49/84) were unaware that ticks can cause disease in livestock or dogs. This study suggests that herders are an at‐risk population in Mongolia with gaps in awareness of TBD risk. Increased surveillance paired with focused outreach to prevent TBDs targeted to the herder population is encouraged.  相似文献   
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