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The lesser house fly Fannia canicularis and other species of fly of animal health and public health importance, were shown to be attracted to “ black‐light “ traps in semi‐open poultry houses permitting free access and strong daylight competition. The fly populations were reduced and the number of ovipositions in the droppings pit apparently decreased. It is shown that the use of these traps, normally reserved for indoor insect control, can be extended to include certain farm situations.  相似文献   
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The stratum corneum measured on fresh frozen sections was found to be considerably thicker than previously reported. It was uniformly permeated with sebum, which also formed an intact film over the skin surface and it could readily be divided into two zones. The living epidermis was approximately half as thick as the stratum corneum.  相似文献   
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Surgical castration is performed on most male piglets in the United States. However, castration is painful and analgesics have been considered to relieve pain. Inhalant gases with analgesic properties allow for a fast induction, have short-term and reversible effects, and are a needle-free option. Nitrous oxide (N(2)O; "laughing gas") has been widely used in human surgery and dental offices as an analgesic, sedative, and anxiolytic drug, yet N(2)O has not been thoroughly investigated for use in farm animals. We hypothesized that the analgesic effect of N(2)O could reduce the pain experienced by piglets during or immediately after castration. Twenty-four male piglets, from 12 litters, were castrated at 3 d of age. One piglet received N(2)O and a littermate received air as a control. After 150 s of exposure to the gas, castration was performed while the piglet remained exposed to the gas. Agitation scores and total vocalization length were recorded during castration. Behavioral observations were continued for 3 d postcastration by using a 5-min scan-sampling method for 4 h the first morning and for 2-h periods in the morning and afternoon of each day thereafter. Body weight gain was measured on the day before castration, at 3 d postcastration, and at weaning. Data were analyzed using a mixed model in SAS (Cary, NC). Nitrous oxide successfully induced anesthesia in all N(2)O piglets, as validated by a skin pinch test and the loss of the palpebral reflex. Total vocalization length was shorter in piglets receiving N(2)O during the induction phase (P = 0.003) but was not different during castration itself because piglets receiving N(2)O awoke and vocalized as much as control piglets (P = 0.87). Agitation scores during the whole procedure were reduced in piglets receiving N(2)O in both frequency (P = 0.005) and intensity (P = 0.026). For 2 h after castration, piglets receiving N(2)O displayed less huddling behavior than did control piglets (P = 0.01). Over the 3 d, piglets receiving N(2)O performed more tail wagging (P = 0.02) and tended to show fewer sleep spasms (P = 0.06) than did control piglets. Piglets given N(2)O tended to have a reduced growth rate compared with control piglets at 3 d postcastration and at weaning (P = 0.05 and P = 0.06, respectively). Nitrous oxide was effective in inducing anesthesia in neonatal piglets during handling. Nonetheless, its analgesic effects appeared insufficient in preventing castration-induced pain.  相似文献   
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ABSTRACT: Foot-and-mouth disease virus (FMVD), one of the most contagious viruses of cloven-hoofed animals, may cause a prolonged, asymptomatic but persistent infection in ruminants, named the "carrier state". However, it remains an open question whether this carrier state occurs in pigs. Here we present quantitative analyses of the duration of FMDV RNA and infectivity in lymphoid and epithelial tissues in experimentally infected pigs with FMDV C-S8c1. The data indicated that although FMDV RNA remained in blood until day 14 post-infection (pi), viremia was cleared by day 7 pi. However, all tissues tested were positive for FMDV until day 14-17 pi. Interestingly, the specific infectivity of FMDV in these tissues was in some cases even higher than the FMDV C-S8c1. We therefore propose that a "pseudopersistent state" may occur in pigs in which virus replicates in lymphoid tissues for a prolonged period of time, thereby representing a potential source of virus.  相似文献   
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Determination and kinetics of enrofloxacin and ciprofloxacin in Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a liquid chromatography/mass spectrometry method. J. vet. Pharmacol. Therap. 34, 142-152. The fluoroquinolones enrofloxacin (EF) and ciprofloxacin (CF) residues were investigated in the edible tissues of two important Asian aquacultured species such as Tra catfish (Pangasianodon hypophthalmus) and giant freshwater prawn (Macrobrachium rosenbergii) using a sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry method. Fish and prawn were treated with medicated feed with multiple doses of EF, in field conditions. A validation study of the analytical method was realized in terms of linearity, specificity, precision (repeatability and within-laboratory reproducibility), recovery and decision limit (CCα). The time needed before the antibiotic disappears from animal tissues or reach the maximum residue limit (MRL, 100μg/kg) was assessed. The concentration values of EF detected in Tra catfish tissue were between the MRL and 2×MRL concentrations, according to the fish density, 7days following the end of the enrofloxacin treatment (20mg/kg body weight per day, for seven consecutive days). The concentration value of ER in prawn tissue was lower than the MRL and the limit of quantification (LOQ, 14μg/kg) 5 and 7days after the stop of the EF treatment (50mg/kg body weight per day, for five consecutive days), respectively. The mean detected levels of CF was much lower in comparison with that of EF, indicating that only a small part of EF is metabolized into CF (<5%) in both Tra catfish and prawn.  相似文献   
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Three experiments were conducted to examine the effects of vitamin E supplementation on feedlot cattle. Vitamin E supplementation did not affect feedlot performance or carcass characteristics of cattle fed a high-concentrate diet (P greater than .1). The major finding was the effectiveness of vitamin E in extending the color stability of displayed beef (P less than .01). Color stability during display of longissimus lumborum steaks from cattle supplemented with 300 IU/d for 266 d, 1,140 IU/d for 67 d, or 1,200 IU/d for 38 d was extended by 2.5 to 4.8 d. Gluteus medius steaks had an extended color display life of 1.6 to 3.8 d. The accumulation of lipid oxidation products, but not aerobic microbes, associated with displayed longissimus lumborum was suppressed for muscle from vitamin E-supplemented steers. Taste panelists detected no difference among longissimus lumborum steaks from control and vitamin E-supplemented steers but found (P less than .01) steaks aged for 21 d to be more tender than steaks aged for 7 d. Supplementing cattle with vitamin E should reduce economic losses associated with discolored beef during retail display.  相似文献   
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