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991.
The hematologic, biochemical, and light and scanning electron microscopic features of eperythrozoonosis in four llamas are described. One female and three male yearling llamas were presented for evaluation of chronic weight loss. Three of four llamas had historical evidence of chronic inflammatory conditions. On examination, multiple clinical problems were apparent, including poorly to non-regenerative anemia, inflammatory disease, and hypoproteinemia. Coccoid- and ring-shaped basophilic organisms were present on the erythrocytes of all the llamas. On scanning electron microscopy, individual, pairs, and clusters of coccoid-shaped organisms were present on the erythrocytes. The organisms measured 0.4 to 0.6 micron in diameter and caused no marked deformation of the erythrocyte membrane. A rare organism could be found that produced a slight indentation into the erythrocyte membrane. The light and scanning electron microscopic morphologic features suggested that the organism was an Eperythrozoon. Serial evaluation of serum iron concentrations of the llamas showed a decrease serum iron in all animals, with a concurrent decrease in the total iron binding capacity and percent transferrin saturation in two of the llamas. Common abnormalities seen on serum electrophoresis included a decrease in albumin and beta serum fraction in all llamas and a decrease in the gamma globulin fraction of two individuals.  相似文献   
992.
The relative antiandrogen-induced prostate involution activity of the newly synthesized hydroxyflutamide pro-drug was compared with that of flutamide in 25 Beagles. Secondary antiandrogen activity of both drugs on the testes and mammary tissue was investigated. Daily oral administration of both compounds at 2 dosages (ie, 2.5 and 5.0 mg/kg of body weight) during a 7-week period was monitored by transabdominal ultrasonography of the prostate twice a week. Cross-sectional area estimates of the prostate gland calculated from oblique dorsoventral, and transverse sonographic measurements were diminished significantly in some of the treated dogs as early as day 14 of drug administration. All treated dogs had significant differences in reduction by day 47. Involution was related directly to dose (P less than 0.05), but no difference was observed between test compounds. Differences in secondary antiandrogen activity were not remarkable. Flutamide was not found to have any activity advantage in vivo over hydroxyflutamide. It was concluded that ultrasonography can be a highly effective means of monitoring prostate size, and of monitoring drug-induced involution over time.  相似文献   
993.
The present study was designed to determine the effects of supplemental fat or oil rich in oleic acid on the fatty acid profiles (FAP) and physical and sensory traits of pork carcasses. Sixty barrows and gilts were equally distributed among five dietary treatments consisting of a control diet of corn and soybean meal and four similar test diets that contained 10% animal fat (45.3 oleic), safflower oil (72.1 oleic), sunflower oil (80.9 oleic) or canola oil (57.7 oleic). The pigs were slaughtered after being fed these diets for 90 d at about 100 kg live weight. Carcass traits, FAP and sensory properties were evaluated for each treatment. First-rib fat thickness, ham muscling score and longissimus muscle areas were not different (P less than .05), but last-rib fat thickness was increased (P less than .05) with the supplemental dietary fat or oils. No differences existed for marbling scores, lean color, firmness or texture scores between the controls and pigs supplemented with either animal fat or safflower oil. However, pigs supplemented with sunflower or canola oil had lower marbling scores, lean color, firmness and texture scores. Fat became softer and more oily (P less than .05) with the supplemental dietary safflower, sunflower and canola oils. Sensory evaluation (loin chops) showed no differences (P less than .05) in sustained juiciness, tenderness or flavor intensity evaluations among treatments. However, the pigs fed canola oil had lower (P less than .05) flavor quality scores or overall palatability evaluations. Chops from the pigs fed canola oil also had 46% more off-flavors than all other treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Beef cattle were treated to synchronize estrus using one of three procedures, and effects on subsequent endocrine responses and fertility were studied. Procedures were 1) feeding .5 mg.head-1.d-1 of melengestrol acetate (MGA) for 21 d (M), 2) feeding .5 mg.head-1.d-1 of melengestrol acetate for 21 d followed 14 d later by a single injection of prostaglandin F2 alpha (M + P) and 3) two injections of prostaglandin (PGF) 14 d apart (P). In Exp. 1, 94 beef cows were assigned to be artificially inseminated 12 h after detection of estrus. Procedures for synchronizing estrus did not affect the proportion of cows observed in estrus within 7 d (mean = 70.2%). However, conception rate of cows treated with MGA alone was lower (P less than .01) than that of cows treated with PGF alone (31.8 vs 78.3%). The conception rate of cows in the M + P group was intermediate (57.1%) but greater than that of cows treated with MGA alone (P less than .10). In Exp. 2, 18 heifers were observed for estrus four times daily and bled daily from 1 wk before predicted estrus until second estrus or 35 d post-treatment. Heifers treated with MGA alone maintained lower concentrations of progesterone and higher concentrations of estradiol-17 beta before first estrus than heifers treated with MGA and PGF or PGF alone (P less than .01). Conception rate following insemination was lower after long-term feeding of MGA than after two injections of PGF. Delaying insemination until after a PGF-shortened cycle 14 d after MGA resulted in an intermediate conception rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
995.
Incidence of early embryonic death (EED) and associated changes in serum cortisol, progesterone and plasma ascorbic acid (AA) in transported mares were investigated. Mares were transported for 472 km (9 h) during either d 16 to 22 (T-3 wk, n = 15) or d 32 to 38 (T-5 wk, n = 15) of gestation. Blood samples were drawn from control, nontransported mares (NT-3 wk, NT-5 wk, n = 24) and transported mares pre-trip, midtrip, and at 0, 12, 24, 48 and 72 h post-transport and daily for the next 2 wk. Incidence of EED between transported and nontransported mares was not different (P greater than .05). Serum cortisol in all transported mares increased (P less than .05) relative to pre-trip values at midtrip and 0 h post-transport. Relative to NT mares, serum cortisol was higher (P less than .05) at midtrip in T-3 wk mares and 0 h post-transport in T-5 wk mares. Serum progesterone in all T mares increased (P less than .05) at midtrip relative to pre-trip values and was higher (P less than .05) in T-3 wk mares than in NT-3 wk mares at midtrip and 0 h post-transport. Post-transport decreases (P less than .05) in concentrations of progesterone were observed in mares that aborted. Plasma AA in transported mares increased (P less than .05) at midtrip in T-5 wk mares and decreased (P less than .05) relative to pre-trip values at 24 and 48 h post-transport (T-3 wk and T-5 wk mares, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
A procedure is described for the isolation of immunoglobulin G (IgG) and immunoglobulin M (IgM) from hyperimmune cervine serum. Hybrids of red deer (Cervus elaphus) and wapiti (Cervus canadensis) were immunised with keyhole limpet hemocyanin (KLH). An immunoglobulin-containing fraction was precipitated from the hyperimmune serum using ammonium sulphate. The antigen-specific immunoglobulins were purified by KLH-conjugated sepharose affinity chromatography and further separated into IgM and IgG by gel-filtration chromatography. Purified immunoglobulin was analysed by polyacrylamide gel electrophoresis and isoelectric focusing. The molecular weights and isoelectric points of the composite chains of cervine IgG and IgM are presented.  相似文献   
997.
Interactions among grain type (grain sorghum, corn or wheat), roughage level and monensin level were studied in four feedlot trials using pen-fed crossbred yearling cattle. In Trial 1, cattle fed high-moisture corn (HMC) were more efficient (.1537 vs .1406 for gain/feed; P less than .01) than cattle fed dry-rolled grain sorghum (DRGS). As level (0, 3, 6, 9%) of dietary roughage was increased, feed efficiency (gain/feed) decreased (.1566, .1461, .1479, .1382; linear, P less than .01). In Trial 2, a grain type (DRGS; dry-rolled corn, DRC; dry-rolled wheat, DRW) x roughage level interaction was observed for daily gain and feed efficiency. Feed efficiency (gain/feed) was decreased when roughage was added to diets containing DRC (.1608 vs .1750) or DRGS (.1674 vs .1465), but not to the diet containing DRW (.1664 vs .1607). In trial 3, a grain type x roughage level x monensin level interaction (P less than .08) was observed for feed efficiency. The addition of 27.5 mg of monensin per kilogram of the 0% roughage-DRC diet tended to improve feed efficiency (.1633 vs .1531), but the addition of monensin to the 7.5% roughage-DRC diet tended to depress feed efficiency (.1476 vs .1575). The addition of either roughage (.1493 vs .1420) or monensin (.1500 vs .1413) to the DRW diet improved feed efficiency. In Trial 4, cattle fed a combination of 75% DRW and 25% DRC were more efficient (.1618 vs .1591; P less than .06) than cattle fed DRC. As level of roughage (0, 3.75, 7.5%) increased, feed efficiency decreased linearly (.1645, .1599, .1569; P less than .0001). Monensin had no effect on feed efficiency. The value of feeding roughage and monensin was variable both across grain types and within similar grain types.  相似文献   
998.
This review summarizes the results of a study on rotaviruses isolated from calves affected by neonatal diarrhea.

The results indicated that rotavirus infection is widespread and supported the evidence for an etiologic role of these viruses in neonatal diarrhea. Differences in virulence among bovine rotaviruses appeared also to be confirmed.

Conventionally reared calves were fully susceptible to the experimental infection induced by rotaviruses originating from heterologous hosts, i.e. monkeys, pigs and rabbits.

When rotavirus strains of bovine, simian and rabbit origin were compared by cross neutralization tests, it was found the simian and porcine strains were indistinguishable and both appeared to relate antigenically to the bovine strain.

Finally, it was proven that feeding newborn calves with colostrum and first milk of their dams, previously vaccinated with an inactivated adjuvanted rotavirus vaccine, could prevent the neonatal diarrhea from occurring.  相似文献   

999.
Antimicrobial resistance (AMR) is a growing global public health problem, which is caused by the use of antimicrobials in both human and animal medical practice. The objectives of the present cross-sectional study were as follows: (1) to determine the prevalence of resistance in Escherichia coli isolated from the feces of pets from the Porto region of Portugal against 19 antimicrobial agents and (2) to assess the individual, clinical and environmental characteristics associated with each pet as risk markers for the AMR of the E. coli isolates.  相似文献   
1000.
The aim of this study was to identify differences in bone shape (height and width) of proximal sesamoid bones (PSB) in 2‐year‐old Thoroughbred racehorses in training. Dorsal 15° proximal‐palmarodistal oblique images of each metacarpophalangeal joint were acquired before the horses started training and at 1 year after the start of exercise and racing. There were no changes in height and width of PSBs induced by training. There was a significant difference of height and width between medial and lateral PSBs. In both forelimbs, the medial PSB was significantly wider and shorter than the lateral PSB. The medial PSB of the right forelimb was significantly wider than that of the left forelimb. These results might explain some limb predilection for fracture of PSBs. The difference in strain pattern between medial and lateral PSBs in different loading conditions needs to be investigated.  相似文献   
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