Identification of a potentially important antigen of pasteurella haemolytica

To identify antigens which may be important for stimulating immunity to pneumonic pasteurellosis, a bovine antiserum to whole P. haemolytica was used to screen a recombinant lambda gt11/P. haemolytica expression library. One of the recombinant bacteriophage clones identified with the bovine antiserum, SW20C, expressed a fusion protein which was also recognized by rabbit antiserum to partially purified P. haemolytica culture supernatant and was found to be immunogenic in guinea pigs. The guinea pig antibody recognized a 100 kDa protein in P. haemolytica cell lysates. Sequence analysis of the cloned DNA from SW20C identified a fragment of 1443 bp with a small open reading frame that was contiguous with the lacZ sequence. The 153 bp P. haemolytica-specific open reading frame encoded a polypeptide of approximately 6kDa. Homology searches of Genbank and the EMBL data bases revealed no homology of this open reading frame with any other bacterial sequences including P. haemolytica leukotoxin and Ssa1. Evaluation of sera from calves that were scored either susceptible or resistant to experimental pneumonic pasteurellosis demonstrated a significant (P < 0.001) correlation between the intensity of the antibody response to the SW20C antigen and resistance to disease.     

Isolation of picornavirus from feces and semen from an infertile bull.

Virus was isolated from semen and fecal samples from a bull with orchitis, testicular degeneration, aspermatogenesis, and loss of libido. Both isolates were classified as picornavirus, bovine enterovirus serotype I, on the basis of physical, chemical, and serologic characteristics. Veterinary practitioners that may suspect viral infection as a cause of bovine infertility should submit both semen and fecal samples for virus isolation and identification.     

Effect of Oil Overlay on Inhibition Potential of Roscovitine in Sheep Cumulus‐Oocyte Complexes

Inhibitors of cyclin‐dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus‐oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor‐free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (?) at 38.5°C and 5% CO₂. At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/?) exhibited total expansion while in both Rosco groups (+/?) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p < 0.05). This meiotic arrest was reversible, and proper meiosis progression also occurred in the Control groups (+/?). So, the culture system without oil overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression.     

Emphysematous gastritis in a horse

A 12-year-old Morgan gelding was examined for colic of 3 days duration. Signs of depression, colic, diarrhea, and endotoxemia persisted despite aggressive medical therapy and surgical exploration. Culture results from gastric fluid and feces yielded many colonies of Clostridium perfringens. This organism also was recovered from peritoneal fluid 10 days after admission; consequently, the horse was euthanized. At necropsy, a localized gas-filled, necrotic stomach wall was found; many mucosal and submucosal gas blebs were visible. Culture of this tissue yielded Clostridium perfringens. Emphysematous gastritis is a fulminant infection of the stomach wall caused by gas-forming organisms that gain access to the submucosa via mucosal defects such as ulcers. This condition has been reported infrequently in people, and the case reported herein represents the first instance of emphysematous gastritis in the horse.     

A 100-year average recurrence interval for the san andreas fault at wrightwood, california

Evidence for five large earthquakes during the past five centuries along the San Andreas fault zone 70 kilometers northeast of Los Angeles, California, indicates that the average recurrence interval and the temporal variability are significantly smaller than previously thought. Rapid sedimentation during the past 5000 years in a 150-meter-wide structural depression has produced a greater than 21-meter-thick sequence of debris flow and stream deposits interbedded with more than 50 datable peat layers. Fault scarps, colluvial wedges, fissure infills, upward termination of ruptures, and tilted and folded deposits above listric faults provide evidence for large earthquakes that occurred in A.D. 1857, 1812, and about 1700, 1610, and 1470.     

Follow-up of mercury levels in fish,human hair and urine in the Madeira and Tapajós basins,Amazon, Brazil

Informal economy of gold mining has contaminated some important river basins in Amazon. Follow-up studies on critical compartments showed some areas with high Hg levels in fish as well as in human hair samples. Average Hg in piscivorous fish in the Madeira river itself was 846 ppb (N=284) with a maximum of 3921 ppb. Mercury in fish from non polluted areas in this basin shows high variability, even for single species. A seasonal variation in Hg content was observed, with higher values at the end of the dry season. In the upper Tapajós basin comparable values were found for fish but with a definite decreasing trend downstream. Average value for piscivorous fish in the whole Tapajós basin is 482 ppb (N=122) with a maximum value of 3770 ppb. Hair Hg was higher in fishing villages in the Tapajós (average: 17 ppm; with N=432 and maximum value of 176 ppm) than in the Madeira (average: 9 ppm; N=169; maximum 71 ppm), and data from some areas of the Tapajós suggest a decrease with time. Mercury was much higher in urine of goldshop workers in Santarém (low Tapajós) than in Alta Floresta (high Tapajbs) and show a decreasing trend in both cases, probably related to the significant decline in gold mining activities during the study period (1986–1994).     

Hyperkalemic Atrial Standstill in Neonatal Calf Diarrhea

Hyperkalemia has been associated with cardiac abnormalities and muscular disorders. Hyperkalemia is a common problem associated with the acid-base and electrolyte disturbances that occur in neonatal calves having acute diarrhea. Occasional calves with acute neonatal diarrhea, metabolic acidosis, and hyperkalemia have cardiac rate or rhythm abnormalities. Bradycardia observed in three such calves was found to represent atrial standstill and was attributed to hyperkalemia. (Journal of Veterinary Internal Medicine 1992; 6:294–297)     

Effect of a ractopamine feeding program on growth performance and carcass composition in finishing pigs

Barrows and gilts (n = 100 per gender) were used to determine the effects of an increasing, decreasing, or constant ractopamine (RAC) dietary concentration on growth performance and carcass characteristics. Pigs, within a gender, were assigned randomly to pens (five pigs per pen and 10 pens per treatment). Pens were assigned randomly to one of four dietary treatments at a starting weight of 71.2 kg, to target an average ending weight of 109 kg. The four dietary treatments (as-fed basis) were 1) control = 0 ppm RAC, wk 0 to 6; 2) RAC step-up = 5.0 ppm, wk 1 to 2; 10.0 ppm, wk 3 to 4; and 20.0 ppm, wk 5 to 6; 3) RAC step-down = 20.0 ppm, wk 1 to 2; 10.0 ppm, wk 3 to 4; and 5.0 ppm, wk 5 to 6; and 4) RAC constant = 11.7 ppm, wk 0 to 6. Feed allocation was recorded daily, and pigs were weighed and feed was weighed back every 2 wk. Jugular blood samples were obtained from two randomly selected pigs per pen on d -3, 7, 21, 35, and 41 for determination of plasma urea nitrogen (PUN) concentrations. Two pigs were selected randomly per pen and sent to a commercial slaughter facility at the end of the 6-wk experimental period. Carcass data were evaluated on an equal time basis and on an equal weight basis by using hot carcass weight (HCW) as a covariate. Overall, ADG and G:F were improved (P < 0.05) for pigs fed RAC compared with control, with no differences among RAC feeding programs. In wk 3 and 4, improvements (P < 0.05) in ADG and G:F were realized with the implementation of a RAC step-up program compared with control pigs. The concentrations of PUN were decreased (P < 0.05) at d 7 and 21 with RAC feeding, and a RAC step-up program maintained the decrease (P < 0.05) in PUN through d 35 and 41. A RAC step-up and constant program increased (P < 0.05) HCW and percent yield. Loin muscle area and percentage of fat-free lean increased (P < 0.05) and backfat thickness decreased (P < 0.05) in pigs fed RAC. If pigs were considered to be on feed for an equal time period, advantages (P < 0.05) were observed for weight of boneless trimmed ham, shoulder and loin for the step-up and constant RAC treatments compared with the controls. Feeding a RAC step-up or constant feeding program resulted in favorable responses in growth performance and yielded more lean pork.