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991.
992.
During the fall of 1982, increased incidence of left displaced abomasum (LDA) was seen in a group of cows fed a complete pelleted ration (3/16 inch) at the university's dairy center during the early postpartum period. Of these, 17.4% developed LDA when fed this experimental ration, whereas only 1.6% of the remaining cows in the herd developed LDA. The latter cows (as a control) were fed loose alfalfa hay, sorghum silage, and an 18% crude protein mix. Most of the fiber in the experimental diet or pelleted diet was alfalfa hay (30% as-fed basis) that was ground through a quarter-inch screen for incorporation into the pellet. Another 10% of the dietary fiber was contributed by cottonseed hulls. Thus, increased incidence of LDA may be associated with short length of the dietary fiber in the pelleted form.  相似文献   
993.
Two hundred eighteen genital tracts of slaughtered female camels were collected and examined. Infundibular cysts were observed in 35 tracts (16%); these were either unilateral (22 cases) or bilateral (13 cases) all containing fluids of different consistencies. The morphological and histological structures of the cysts were recorded. The bacteriological investigation and physicochemical analysis of cyst contents were carried out. Aeromonas hydrophila was isolated from 68.5% of cases. Rectal palpation and ultrasound technique were compared for the diagnosis of the cysts antemortem.  相似文献   
994.
A 4 yr old intact male rat terrier presented with severe bilateral nonresponsive panuveitis. Bilateral uveitis, blepharospasm, conjunctival hyperemia, diffuse corneal edema, peripheral bullous retinal detachment, and secondary ocular hypertension were noted. Ocular lesions progressed despite aggressive medical treatment and were followed by cutaneous depigmentation and crusting along the nasal planum. Intensive oral and topical anti-inflammatory and topical antiglaucoma medications were administered, but the ocular disease progressed. A bilateral enucleation was performed. Uveodermatologic syndrome was diagnosed from histopathologic examination of a skin biopsy as well as histopathology of both globes after bilateral enucleation. To maintain control of the dermatologic lesions, oral azathioprine was initiated, but it was not well tolerated by this patient. Immunosuppressive doses of oral cyclosporine and anti-inflammatory doses of oral prednisone were used to control the depigmentation and crusting skin lesions.  相似文献   
995.
We determined the prevalence and mean intensity of Trichinella sp. infection in coyotes from six counties in Oklahoma and one in northern Texas. Tongues from 77 coyotes were examined using histology and artificial tissue digestion. Histological examination showed a prevalence of 3.9% (3 of 77) whereas the prevalence was 6.5% (5 of 77) based on artificial digestion of 5.0 g of muscle from coyote tongues. One sample was positive for Trichinella sp. on histology but negative by artificial digestion. Combining data from both diagnostic techniques showed that six of 77 (7.8%) coyotes were infected with Trichinella spp. The mean intensity of Trichinella sp. larvae ranged from 0.2 to 66.2 with an average of 16.0 larvae per gram (LPG) of tongue. Genotyping results demonstrated that the coyotes were infected with Trichinella murrelli. This is the first report of T. murrelli infection in coyotes in Oklahoma. T. murrelli had previously been isolated from coyotes in Texas.  相似文献   
996.
997.
The Vsp proteins are the major outer membrane proteins of Brachyspira hyodysenteriae, the causative agent of swine dysentery. Eight vsp genes have been identified in B. hyodysenteriae strain B204, arranged into two four-gene loci, and at least two of the corresponding proteins are produced in vitro. The aims of this study were to characterise the vsp genes of the virulent Australian B. hyodysenteriae strain X576 and their corresponding proteins, Genomic sequence comparison with strains B204 and WA1 demonstrated that the number of vsp genes varies between B. hyodysenteriae strains, although the chromosomal locations of the vsp gene loci are consistent. We identified two additional vsp-like genes, designated vspI and vspJ, in each of the three strains. Double SDS-PAGE was used to demonstrate that Vsp proteins of B. hyodysenteriae strain X576 form multimeric protein complexes in the outer membrane that are stable in 6M urea but dissociate after boiling. The Vsp complexes primarily consisted of VspF but also contain VspE and VspI. VspD was also found in a series of complexes slightly larger than the more abundant VspF complexes. Vsp proteins are purported to be antigenic; however little direct data are available to support this claim. In this study convalescent pig sera did not bind denatured Vsp proteins by Western blotting, but did bind the Vsp complexes on Western blots, showing that conformational epitopes may be important in immune recognition of these major outer membrane proteins. This is the first definitive demonstration of the antigenicity of these proteins in swine dysentery.  相似文献   
998.
The objective of three experiments was to determine the impact of supplementing sericea lespedeza (Lespedeza cuneata; SL) in three concentrations in a loose or pelleted diet on gastrointestinal nematodes (GIN) in small ruminants. Experiments on lambs were conducted at the USDA, Agricultural Research Service in Booneville, AR (Exp. 1) and at Louisiana State University in Baton Rouge, LA (Exp. 2); an experiment on goat kids occurred at University of Maryland-Eastern Shore (Exp. 3). Exp. 1 used crossbred hair sheep lambs naturally infected with GIN that were randomly allocated to diets containing 0, 25, 50, and 75% SL diets (n=11 or 12/diet). Exp. 2 consisted of Haemonchus contortus-inoculated crossbred wool breed lambs that were blocked by gender and FEC and randomly assigned to 0, 25, 50, or 75% SL diet (n=8/diet). Fecal egg counts (FEC) and blood packed cell volume (PCV) were not influenced by SL supplementation in Exp. 1 and 2. Exp. 3 consisted of naturally GIN infected Boer crossbred goat kids in individual pens. Kids were blocked by FEC and randomly allotted to treatments of 0, 20, 40, or 60% SL with 9-13 goats/diet. The more SL fed, the greater the reduction in FEC (P<0.001). There was an increase in PCV in SL fed goats (P<0.001). Larval speciation at the end of the experiment indicated that feces from control animals produced 43% H. contortus larva while 20, 40 and 60% SL resulted in 39%, 35% and 31% H. contortus larvae, respectively. Feeding dried SL may be less effective in lambs than kids, though concurrent studies must be conducted to confirm this.  相似文献   
999.
Four experiments evaluated the effect of implant dose and release pattern on performance and carcass traits of crossbred beef steers. In Exp. 1, steers (4 to 7 pens/treatment; initial BW = 315 kg) were fed an average of 174 d. Treatments were 1) no implant (NI); 2) Revalor-S [120 mg of trenbolone acetate (TBA) and 24 mg of estradiol 17β (E(2)); REV-S]; 3) Revalor-IS followed by REV-S (cumulatively 200 mg of TBA and 40 mg of E(2); reimplanted at 68 to 74 d; REV-IS/S); and 4) Revalor-XS (200 mg of TBA and 40 mg of E(2); REV-X). Carcass-adjusted final BW was greater (P < 0.05) for REV-X and REV-IS/S than for REV-S (610, 609, and 598 kg, respectively). Daily DMI did not differ (P > 0.10) among the 3 implants, but carcass-adjusted G:F was greater (P < 0.05) for REV-X and REV-IS/S than for REV-S (0.197 and 0.195 vs. 0.188). Both HCW and LM area were greater (P < 0.05) for REV-X and REV-IS/S than for REV-S. Marbling scores were greatest (P < 0.05) for REV-S and least (P < 0.05) for REV-IS/S; REV-X was intermediate to NI and REV-IS/S. In Exp. 2, steers (10 pens/treatment; initial BW = 391 kg) were fed 131 d, with treatments of REV-S, REV-IS/S (reimplanted at 44 to 47 d), and REV-X. Carcass-adjusted final BW (598 kg), ADG (1.6 kg), DMI (9.4 kg), G:F (0.17), and HCW did not differ (P > 0.10) among treatments. The percentage of Choice was less (P < 0.05) and percentage of Select greater (P < 0.05) for REV-IS/S than for REV-S and REV-X. In Exp. 3, steers (10 pens/treatment; initial BW = 277 kg) were fed 197 d and received either REV-IS/S (reimplanted at 90 to 103 d) or REV-X. Carcass-adjusted final BW (625 vs. 633 kg) and ADG (1.81 vs. 1.76 kg) were greater (P < 0.05) for REV-X-implanted steers. Daily DMI did not differ, but G:F tended (P < 0.10) to be increased and HCW was greater (P < 0.05) for REV-X than for REV-IS/S. In Exp. 4, steers (8 pens/treatment; initial BW = 238 kg) were fed 243 d and received either REV-IS/S (reimplanted at 68 to 71 d) or REV-X. Carcass-adjusted final BW (612 kg), ADG (1.54 kg), DMI (7.55), and G:F (0.21) did not differ (P > 0.10) for REV-IS/S and REV-X-implanted steers. Carcass traits did not differ among implants, but the percentage of Choice carcasses was greater (P < 0.05) and percentage of Select was less (P < 0.05) for REV-X than for REV-IS/S. These data indicate that when TBA/E(2) dose is equal, the altered release rate of REV-X can improve performance and quality grade, but these effects depend on duration of the feeding period and timing of initial and terminal implants.  相似文献   
1000.
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