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1.
Metabolic and production responses are reported for 72 cows treated with bovine somatotropin (BST) for 30 days starting at day 70 of lactation. Of these 72 cows, 48 had been exposed in the preceding lactation to long-term treatment with BST at 3 dosages and 24 (controls) had not been given BST. Approximately half of the cows in each group were parity-2 cows, the rest were older. Comparisons between groups were made separately for parity-2, and older cows. Analyses, using pretreatment values of each variable as a covariate, indicated that older cows, but not parity-2 cows, significantly (P less than 0.05) increased milk production during treatment. Parity-2 cows, however, had a significantly higher milk fat percentage than controls following treatment. Cows treated with 51.6 or 86 mg BST/d in both parity groups had significantly higher serum-free fatty acids than controls. Estimated net energy balances were significantly lower for older treated cows, but did not significantly differ from controls for parity-2 treated cows. Older cows in the 86 mg of BST/d group tended to have higher concentrations of blood glucose than did older control-group cows. Treatment with BST did not significantly increase serum ketone concentrations in any group of animals, and none of the cows developed clinical ketosis during this period. Estimated net energy balance (ENEB) during treatment was a significant (P less than 0.05) covariate for free fatty acid concentrations in older cows and for milk fat percentage in parity-2 cows. Covariate adjusted analyses, using ENEB during treatment as a covariate, indicated that lipolytic stimuli already acting may be enhanced by treatment with BST, but a negative energy balance was not a necessary precondition for free fatty acid concentrations to increase following somatotropin treatment. Similarly, milk fat percentages for parity-2 treated cows were significantly (P less than 0.05) higher during treatment than controls when ENEB during treatment was used as a covariate. Increased milk fat concentrations in parity-2 treated cows were not associated with significant increases in the ratio of C18:C4-10 milk fatty acids, indicating that increased milk fat resulted from either an increase in incorporation of C18 fatty acids into milk fat coupled with an increase in de novo mammary synthesis of C4-10 milk fatty acids or an increase in C12-16 fatty acids that may arise either from increased tissue mobilization, from diet, or from de novo mammary synthesis.  相似文献   
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OBJECTIVE: To assess the effect of maternal cells or cellular components on neonatal immune responses to intracellular pathogens in calves. ANIMALS: 15 Holstein calves. PROCEDURES: Calves were fed whole colostrum, frozen colostrum, or cell-free colostrum within 4 hours after birth. Leukocytes were obtained from calves before feeding colostrum and 1, 2, 7, 14, 21, and 28 days after ingestion. Proliferative responses against bovine viral diarrhea virus (BVDV) and mycobacterial purified protein derivatives were evaluated. Dams received a vaccine containing inactivated BVDV, but were not vaccinated against mycobacterial antigens. RESULTS: All calves had essentially no IgG in circulation at birth, but comparable and substantial concentrations by day 1. Calves that received whole colostrum had enhanced responses to BVDV antigen 1 and 2 days after ingestion of colostrum. In contrast, calves that received frozen colostrum or cell-free colostrum did not respond to BVDV. No differences were identified among the 3 groups in response to mycobacterial antigens. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that transfer of live maternal cells from colostrum to neonatal calves enhanced responses to antigens against which the dams had previously responded (BVDV), but not to antigens to which the dams were na?ve (mycobacterial purified protein derivatives). Results suggested that cell-mediated immune transfer to neonates can be enhanced by maternal vaccination.  相似文献   
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Results are presented for monitoring Salmonella infection by bacteriological culture and immune response (enzyme linked immunosorbent assay (ELISA) and haptoglobin) testing of samples collected from beef cattle at a single feedyard sampled over time. A total of 120 beef steers were examined on entry to the feedyard and at days 30, 60, and at time of slaughter (120-150 days). Isolations of Salmonella decreased over time from 40% of the steers sampled at day 0 to 0% at slaughter, whereas serological results varied by serogroup. Seropositivity increased for Salmonella group B up to day 60, and subsequently decreased to about half of the 60-day positivity rate at the time of slaughter. No significant changes in seropositivity were detected during the course of the study for the four other Salmonella serogroups (C1, C3, D1, and E1). Haptoglobin measurements were not a good indicator of Salmonella infection status. Sequential Salmonella testing either by culture, ELISA, or both could be used to monitor pathogen control practices.  相似文献   
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A monitoring program of the pre-treatment susceptibility of clinical isolates of bacteria from diseased dogs and cats was active between the years 2002 and 2009. Susceptibility of each isolated strain to a panel of nine antibiotics (amoxicillin/clavulanic acid, ampicillin, penicillin, clindamycin, doxycycline, enrofloxacin, marbofloxacin, trimethoprim and trimethoprim/sulfamethoxazole) was assessed. The Minimum Inhibitory Concentration (MIC) of marbofloxacin was also determined by a standardized microdilution technique following CLSI recommendations. In total, 1857 bacterial strains were collected throughout Europe from cases of otitis, respiratory, urinary and dermatological infections. Although bacterial susceptibility varied for each of the antibiotics within the panel, patterns of susceptibility were similar to those described in the literature for comparable time periods and geographical areas. With a clinical resistance varying from 0 to 14.48% against the isolated strains, marbofloxacin susceptibility was very high and remains an effective antibiotic for the treatment of otitis, urinary, respiratory and dermatological infections in companion animals.  相似文献   
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Differential diagnoses for regurgitation and vomiting in dogs include diseases of the gastroesophageal junction. The purpose of this cross‐sectional study was to describe ultrasonographic characteristics of the abdominal esophagus and gastric cardia in normal dogs and dogs with clinical disease involving this region. A total of 126 dogs with no clinical signs of gastrointestinal disease and six dogs with clinical diseases involving the gastroesophageal junction were included. For seven euthanized dogs, ultrasonographic features were also compared with gross pathology and histopathology. Cardial and abdominal esophageal wall thicknesses were measured ultrasonographically for all normal dogs and effects of weight, sex, age, and stomach filling were tested. Five layers could be identified in normal esophageal and cardial walls. The inner esophageal layer was echogenic, corresponding to the cornified mucosa and glandular portion of the submucosa. The cardia was characterized by a thick muscularis, and a transitional zone between echogenic esophageal and hypoechoic gastric mucosal layers. Mean (±SD) cardial wall thicknesses for normal dogs were 7.6 mm (±1.6), 9.7 mm (±1.8), 10.8 mm (±1.6), 13.3 mm (±2.5) for dogs in the <10 kg, 10–19.9 kg, 20–29.9 kg and ≥30 kg weight groups, respectively. Mean (±SD) esophageal wall thicknesses were: 4.1 mm (±0.6), 5.1 mm (±1.3), 5.6 mm (±1), and 6.4 mm (±1.1) for the same weight groups, respectively. Measurements of wall thickness were significantly correlated with dog weight group. Ultrasonography assisted diagnosis in all six clinically affected dogs. Findings supported the use of transabdominal ultrasonography as a diagnostic test for dogs with suspected gastroesophageal disease.  相似文献   
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Bushmeat, defined as meat derived from wild animals, is a potential source of zoonotic pathogens. Bushmeat from restricted animals is illegal to import into the United States under US federal regulations. We reviewed US Centers for Disease Control and Prevention (CDC) port of entry surveillance records from September 2005 through December 2010 and conducted focus group studies to describe trends in and reasons for bushmeat importation into the United States. In total, 543 confiscated bushmeat items were recorded. Half of the confiscated bushmeat items identified were rodents. Africa was the most frequent continent of origin. Seasonality was evident, with bushmeat confiscations peaking in late spring to early summer. Four times more bushmeat was confiscated during an enhanced surveillance period in June 2010 compared with the same period in previous years, suggesting that routine surveillance underestimated the amount of bushmeat detected at US Ports of Entry. Focus groups held in three major US cities revealed that bushmeat importation is a multifaceted issue. Longstanding cultural practices of hunting and eating bushmeat make it difficult for consumers to acknowledge potential health and ecologic risks. Also, US merchants selling African goods, including bushmeat, in their stores have caused confusion among importers as to whether importation is truly illegal. Enhancing routine surveillance for bushmeat and consistent enforcement of penalties at all ports of entry, along with health education aimed at bushmeat importers, might be useful to deter illegal importation.  相似文献   
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Transposable elements are presents in all known genomes so far, and have the faculty of changing their genomic location and/or number of copies within the genome. They are mobile endogenous genetic elements, with a large variety of structure and transposition mechanism. In crops, they compose the major part of the nucleic DNA, up to 80% in some cereals like maize and wheat. Despite their omnipresence, they are largely unknown and uncharacterized within the Poaceae family. In this review, we describe a possible classification of the elements present in this family, some of their known transposition mechanism, their known activity and possible action in crops, and their possible origin.  相似文献   
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Two laboratory experiments were carried out to determine the potential effects of lime application on the behavior of earthworms inoculated in an acidified forest soil from Vosges Mountains. Several field soils were studied: (i) a non-limed soil that had received decades of atmospheric acid depositions (pHH2O=3.9), (ii) an in situ limed soil that had been limed 6 years before at 2.5 t ha?1 (pHH2O=4.2) and (iii) in vitro limed soils composed of non-limed soil mixed with several lime amounts in the laboratory corresponding to field rates of 1, 2.5, 5, 10 and 20 t ha?1. Firstly, we adapted the earthworm avoidance test (ISO, 2006) by using Eisenia fetida as the model organism and Lumbricus castaneus, a local species, to determine earthworm preference between non-limed and limed soils. Secondly, a cast production (CP) study was performed according to Capowiez et al. (2009) with Lumbricus terrestris, in seven different treatments (non-limed soil, in situ limed and five in vitro limed soils with pH from 5 to 6.3). Both species avoided the non-limed soil in favour of in situ and in vitro limed soils for both species. Results of the CP bioassay showed that the bioturbation behavior of L. terrestris significantly increased with the increase of soil pH, following a dose–response curve. However, in the long term (>6 years), the application of lime was insufficient to significantly improve soil conditions for enhancing earthworm activity. In conclusion, we may recommend this kind of earthworm laboratory tests with field soils to assess any changes in soil quality over time due to liming application.  相似文献   
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