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Pregnancy‐associated glycoproteins (PAG) are secreted by the binucleate giant cells of the ruminant placenta and enter maternal circulation at the time of placental attachment. The IDEXX Milk Pregnancy Test (IDEXX, Westbrook, ME) detects a subset of PAG in milk. Although designed as a management tool for dairy cows, there is potential for using the milk PAG test in beef cows. Our objective was to compare the performance of the milk PAG ELISA with a gold standard method for pregnancy diagnosis and determine the agreement between milk and serum PAG analysis in lactating beef cows. Angus and Angus‐crossed cows (n = 332) from two Michigan beef herds were enrolled in this study. Cows were subjected either to timed artificial insemination followed by exposure to a bull or exclusively exposed to a bull. The bulls and cows were separated 30 days prior to examination. Serum and milk samples were collected and submitted within 24 h of collection to a commercial laboratory for PAG analysis using the IDEXX Milk Pregnancy Assay (milk) and the IDEXX Bovine Pregnancy Assay (serum). Concurrently with milk and serum collection, each cow was examined transrectally by palpation or ultrasonography. When compared to transrectal examination, the performance (and 95% confidence intervals) of the milk PAG ELISA was sensitivity of 99.7% (99.0–100.0%) and specificity of 80.8% (65.6–95.9%). The lower specificity is likely due to the low prevalence (9.9%) of open cows (n = 30) in the herds examined. Of the 332 cows examined, 1.8% (n = 6) were classified as rechecks using the milk PAG ELISA. Results of the milk and serum PAG ELISA were in high agreement (kappa coefficient = 0.91). The milk PAG ELISA was accurate in predicting pregnancy status using milk collected from beef cattle between days 37 and 125 post‐insemination and may be useful for aiding management decisions in beef herds.  相似文献   
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Summary PEG fusion solution for leaf protoplasts of Petunia parodii and cell suspension protoplasts of albino P. hybrida cv. Comanche was supplemented with 0.01–1.0% (w/v) Pluronic F-68. This stimulated protoplast fusion overall, including parental homokaryon formation, with increased means of 23% and 83% respectively, over appropriate controls using 1.0% (w/v) surfactant added to the standard PEG solution. Interestingly, the percentage heterokaryon formation increased near 2-fold (P<0.001) for fusogen solutions supplemented with 0.01% (w/v) Pluronic. Protoplasts regenerated to colonies in KM8P/KM8 liquid medium, indicating no adverse effects of Pluronic F-68 on viability, both in the short and longer terms.Abbreviations BA 6-benzyladenine - MS Murashige & Skoog (1962) - NAA -naphthaleneacetic acid - PEG polyethylene glycol  相似文献   
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The objective of this study was to evaluate the meat quality and shelf life of steaks from steers fed dried distillers grains with solubles (DDGS) or dried corn gluten feed (CGF) compared with soybean meal with corn (SBM) as a protein supplement from weaning to slaughter. Angus cross steers (n = 81; BW = 306 ± 26.1 kg) were randomly assigned to pens (n = 9) and fed a stocker diet of corn silage (75% of DM) with DDGS, CGF, or SBM and ground ear corn. After 84 d of stockering, 12 steers (BW = 397 ± 15.3 kg) were randomly selected from each treatment and finished using the same protein supplement at 25% of DM for 100 d. Carcass data were collected (24 h) and the longissimus lumborum was fabricated into steaks at 48 h postmortem. Steaks were assigned to proximate analysis, Warner-Bratzler shear force (7-, 14-, or 21-d aging), and retail display (1, 3, 6, or 9 d). Protein source did not affect carcass yield, quality, or longissimus lumborum composition (P > 0.05). After 7 d of aging, DDGS and CGF steaks were more tender (P < 0.01) than SBM, but were similar (P = 0.30) after 14 and 21 d of aging. Feeding corn by-products did not influence subjective overall color acceptance (P = 0.17) in this study, but acceptance declined over time (P < 0.01). Subjective redness was similar (P > 0.05) among diets except SBM steaks were more red (P < 0.01) than DDGS after 9 d. On d 3 and 6 of retail display, CGF steaks exhibited more discoloration (P < 0.04) than SBM or DDGS steaks. However, after 9 d DDGS steaks were more discolored (P < 0.01) than CGF or SBM. Objective L* was lighter for CGF (P < 0.04) over 9 d of display, and all treatments became darker (P < 0.01) as time increased. Redness (a*) declined (P < 0.01) over time with SBM steaks maintaining more color in the red spectrum than CGF and DDGS after 6 d of display. Protein source did not affect (P > 0.05) the rate of lipid oxidation. Total SFA concentrations were similar (P > 0.05) among treatments; however, total MUFA were less (P < 0.05) and total PUFA concentrations were greater (P < 0.05) in DDGS steaks compared with SBM or CGF steaks. These data show that DDGS or CGF can be fed as a protein supplement at 25% DM from weaning until slaughter while maintaining meat quality when compared with steers fed soybean meal as a protein supplement.  相似文献   
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Canine soft tissue sarcomas (STSs) are locally invasive mesenchymal neoplasms. Electrochemotherapy (ECT) is an antitumour local ablative treatment that uses electric pulses to enhance the intracellular delivery of cytotoxic drugs. The aim of this retrospective study was to review the current treatment for STSs and to evaluate the efficacy and safety of ECT with bleomycin in canine STSs. Fifty‐two dogs with 54 STSs were included. Three groups were arranged: (a) ECT alone, (b) intra‐operative ECT and (c) adjuvant ECT. Signalment, tumour size, location, histological grade and margins and ECT parameters were collected. Recurrence rate (RR) and disease‐free interval (DFI) were calculated. Treatment toxicity was assessed using a 6‐point scale. STSs were mostly located on limbs (77.8%). Median tumour size was 4.3 cm (range 0.4‐17.0 cm). Most STSs were grade I (47.7%) and II (50.0%), and histological margins were incomplete in 94.5% of cases. Two complete remissions, one partial remission and one stable disease were recorded in group 1. Group 2 and 3 were similar for tumour location, size and grade, histological margins, treatment toxicity, pulse frequency and voltage. Moreover, RR and DFI were similar between group 2 and 3 (23% and 25%, 81.5 and 243 days, respectively). Local toxicity post ECT was mild (score ≤ 2) in 66.7% of cases. Higher toxicity score was associated with higher pulse voltage (1200 vs 1000 V/cm) (P = 0.0473). ECT coupled with bleomycin resulted safe and efficient in tumour local control and should be considered as an option for treatment of canine STSs.  相似文献   
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Environmental cleaning was assessed at a small animal veterinary referral hospital and associated primary healthcare facility. A convenience sample of surfaces was contaminated with fluorescent dye, and then cleaning was assessed 24 hours later by UV light visualisation. Five hundred sixty-three sites were assessed; however, 70 sites were unable to be evaluated 24 hours later because equipment had been removed or because rooms were occupied at the time of re-evaluation. Overall, dye was removed from 212/493 (43%) of sites. Site-specific rates ranged from 14% (computer keyboards and mice, 9/66 site cleaned) to 81% (examination tables, 44/54 sites cleaned). There was a significant difference in the prevalence of successful cleaning by general location (P < 0.0001) and surface type (P < 0.0001). Environmental tagging was an easy and low-cost tool to assess cleaning practices. Results prompted further infection control investigations to explain selected deficiencies, leading to identification of inadequacies in protocols and practices. Environmental tagging may be a useful infection control tool for establishing baseline cleaning rates, identifying deficiencies in protocols, evaluating the effects of interventions and education of personnel.  相似文献   
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