Intrauterine infusion of a pathogenic bacterial cocktail is associated with the development of clinical metritis in postpartum multiparous Holstein cows.

Metritis is a uterine disorder common in dairy cattle caused by bacterial infection, with greater incidence in the early postpartum period. The disease causes delayed uterine involution, with a fetid, watery, red-brown discharge, with animals presenting different clinical signs including fever, dullness, inappetence, decreased milk yield, and dehydration. We developed an in vivo model of clinical metritis in Holstein multiparous cows using a pathogenic cocktail of Escherichia coli, Fusobacterium necrophorum, and Trueperella pyogenes. A total of 36 multiparous cows were randomly allocated to 1 of 3 treatment groups of 12 animals each. Cows assigned to the control group received an intrauterine administration of sterile saline solution, those in the low-dose group received a bacterial inoculum containing 106 cfu of Escherichia coli, Trueperella pyogenes, and Fusobacterium necrophorum; and those in the high-dose group received 109 cfu of these same organisms, all within 24 h of parturition. Clinical signs; milk yield; dry matter intake; serum concentration of acute phase proteins, metabolites, and cytokines; and bacterial counts in vaginal discharge were measured from parturition until 14 d in milk. Based on clinical signs, cows in the low-dose group had a greater incidence of metritis (83.3%) compared with the control (9%) or high-dose (25%) group. The low-dose group also had lesser dry matter intake compared with controls and an acute phase protein profile that typified metritis. The low-dose group presented greater relative abundance of bacteria from the genus Fusobacterium in the vaginal discharge compared with control cows, and the high-dose group was similar to the control group. Unexpectedly, intrauterine infusion of cows with a lower dose of bacteria was more effective than a higher dose, indicating that the bacterial load may affect metritis incidence in a nonlinear manner. These findings demonstrate that clinical metritis can be experimentally induced in postpartum multiparous Holstein cows, creating a relevant model for the study of uterine diseases.

Intramammary immunization with ultraviolet-killed Escherichia coli shows partial protection against late gestation intramammary challenge with a homologous strain.

The objective of this study was to evaluate the efficacy of intramammary immunization with UV-killed Escherichia coli ECC-Z on prevention of intramammary colonization after a challenge with a dose of the homologous E. coli ECC-Z live bacteria. A total of 10 cows were included in a study to evaluate the efficacy of intramammary immunization. All 10 cows received an intramammary immunization of 100 cfu of UV-killed E. coli ECC-Z bacteria into one hind quarter at the time of dry off. Approximately 2wk before the anticipated calving date, both hind quarters of all cows were challenged with 100 cfu of live E. coli ECC-Z bacteria. Five of the cows were vaccinated parenterally with a commercial J5 bacterin, and 5 cows served as controls with no parenteral vaccination. The cows were then followed over time and infection risk, clinical scores, somatic cell count, and milk production were observed over time. The results of these 10 cows showed partial protection of intramammary immunization on the outcome of a subsequent homologous intramammary challenge. Immunization resulted in a lower probability of infection, a lower bacteria count, lower somatic cell counts and milk conductivity, a lower clinical mastitis score, and increased milk production compared with unimmunized control quarters. Once the analysis was corrected for immunization, parenteral J5 vaccination had no significant effect on any of the measured parameters. These results provide the first evidence that intramammary immunization may improve the outcome of an intramammary E. coli infection in late gestation and onset of mastitis immediately following parturition. Unlike systemic vaccination, which generally does not reduce the intramammary infection risk, the intramammary immunization did show a 5-times reduced odds of an established intramammary infection after challenge. Cytokine profiles indicated a local return of proinflammatory response after challenge as the data showed a more pronounced increase in in IFN-γ with a subsequent negative feedback due to a spike in the level of IL-10 in immunized quarters relative to nonimmunized quarters. Although these results are preliminary and obtained on only 10 cows, the results provide insight into the biological benefits of triggering mucosal immunity in the mammary gland.

Study of cavernosal arterial anatomy using color and power Doppler sonography: impact on hemodynamic parameter measurement.

PURPOSE: We report on color and power Doppler ultrasound to study cavernosal arterial anatomy, and evaluate the impact of vascular anatomy on the measurement of hemodynamic parameters. MATERIALS AND METHODS: Cavernosal arterial anatomy of 42 patients with erectile dysfunction was evaluated using color and power Doppler ultrasound. A computerized waveform analysis was used to measure peak systolic velocity, end diastolic velocity and resistive indexes at various sites, including the penile crura, and proximal mid and distal penile shaft. Hemodynamic parameters were measured in each artery in cases of bifurcated or multiple cavernosal arteries. RESULTS: A total of 80 corpora were adequately evaluated. We observed a single artery without major proximal branches in 37 corpora, a single artery with major proximal branches in 17, bifurcated arteries in 15, 2 cavernosal arteries in 4 and marked arterial tortuosity in 1. In 6 corpora the main cavernosal artery arose from the superficial dorsal artery. The peak systolic velocity was highest at the proximal and decreased progressively at the distal site. The peak systolic velocity plus or minus standard deviation at the mid shaft averaged 69.3+/-30.0% of that at the proximal penile shaft. Of the 15 corpora with bifurcated arteries 67% had a 40% or greater difference in peak systolic velocity between the branches. Complete or partial occlusion of the cavernosal artery was identified in 3 corpora, and a dramatic difference in peak systolic velocity proximal and distal to the stenotic area was demonstrated. CONCLUSIONS: Cavernosal arterial anatomy is variable and hemodynamic parameters differ at various sites of measurement. Parameters should be measured at a consistent proximal site to obtain a reliable assessment. Variations in vascular anatomy and cavernosal artery pathology should be considered when interpreting color Doppler sonography and before penile vascular surgery.

Preoperative hyperbaric oxygen therapy for radiation induced injuries.

PURPOSE: We present our experience with preoperatively administered hyperbaric oxygen therapy to patients who have sustained significant therapeutic radiation induced soft tissue injuries and subsequently undergo planned abdominal intervention/surgery. MATERIALS AND METHODS: From February 1993 to May 1997, 5 patients with a history of complications following therapeutic radiation were prospectively treated with hyperbaric oxygen before a planned abdominal operation. RESULTS: All patients had uneventful hospital courses. An additional procedure was eventually necessary in 2 patients but with fewer radiation related problems following hyperbaric oxygenation. CONCLUSIONS: Hyperbaric oxygenation may improve postoperative outcomes when given before planned open operations in patients with previous therapeutic pelvic irradiation and a history of radiation related complications.

Hemodynamic patterns of pharmacologically induced erection: evaluation by color Doppler sonography.

PURPOSE: Penile erection is achieved through hemodynamic mechanisms that can be assessed best with color flow imaging and Doppler waveform analysis. We performed dynamic studies using computer assisted analysis to assess the hemodynamic patterns of pharmacologically induced erection. MATERIALS AND METHODS: A total of 73 color Doppler ultrasound studies was performed in 66 patients with erectile dysfunction. Various blood flow parameters, including peak systolic velocity, end diastolic velocity, mean flow rate, resistive index and artery diameter, were observed continuously and recorded frequently for about 30 minutes after intracorporeal injection of papaverine/phentolamine/prostaglandin E1 mixture. A computerized Doppler waveform analysis of 3 curves or greater was performed for each recording to minimize error. A second injection was administered if the first injection failed to induce a rigid erection. Status of the erection was observed and recorded throughout the study. A computerized graph was generated for each corpus. RESULTS: After intracorporeal injection the time to reach normal or peak velocity varied from 1 to 24 minutes. Among 146 corpus units in 73 color Doppler ultrasound studies we observed the following hemodynamic patterns: I-normal maximal peak systolic velocity (35 cm. per second or greater), sustained; Ia-end diastolic velocity 0 or less with complete erection response (19 units); Ib-end diastolic velocity greater than 0 or incomplete erection response (14 units); II-normal maximal peak systolic velocity (35 cm. per second or greater), transient; IIa-end diastolic velocity 0 or less with complete erection response (21 units); IIb-end diastolic velocity greater than 0 or incomplete erection response (12 units); III-borderline maximal peak systolic velocity (30 to 35 cm. per second); IIIa-end diastolic velocity 0 or less with complete erection response (10 units); IIIb-end diastolic velocity greater than 0 or incomplete erection response (8 units); IV-low maximal peak systolic velocity (less than 30 cm. per second); IVa-end diastolic velocity 0 or less with complete erection response (24 units); and IVb-end diastolic velocity greater than 0 or incomplete erection response (38 units). CONCLUSIONS: Erection is a complex and dynamic process. A new classification of hemodynamic patterns is presented that aids in assessing and interpreting more thoroughly blood flow parameters to stratify more precisely the hemodynamic patterns of erectile dysfunction.

Enzyme-linked immunosorbent assay for the detection of Salmonella enteritidis infection in chickens.

An ELISA was developed and tested for its ability to detect antibodies against Salmonella enteritidis in chickens. Various features of the ELISA were evaluated and optimized. The outer membrane protein antigens selected by use of the protein immunoblotting method made the assay specific and sensitive. The assay was evaluated in chickens experimentally infected with S enteritidis. Blood samples collected at weekly intervals after experimental infection with S enteritidis were analyzed by ELISA. Results of the ELISA were compared with those of conventional serum plate and microagglutination tests. The ELISA was more sensitive and specific in the detection of S enteritidis infection than the other 2 conventional tests.

Feasibility of using proteins from Salmonella gallinarum vs. 9R live vaccine for the prevention of fowl typhoid in chickens.

Proteins from a field strain of Salmonella gallinarum MSG1 were compared with 9R live vaccine strain for their protection against experimental fowl typhoid in chickens. Proteins from S. gallinarum gave better protection than the 9R live vaccine as measured by clearance of challenge organism from internal organs. Proteins given twice with an adjuvant at 200 micrograms/100 g body weight resulted in 95% protection, compared with 60% protection with 9R given orally. The 9R live vaccine produced more hepatic and splenic lesions and, when administered orally as a single dose, was the least protective (60%). In the group vaccinated subcutaneously with a single dose of 9R without an adjuvant, both the challenge strain and the 9R vaccine strain were isolated from the ovaries of some birds. All chickens vaccinated with 9R strain or with proteins developed antibodies detectable by microagglutination test, and in some vaccinated groups as many as 100% of the birds developed antibody levels detected by seroagglutination.

Studies on feasibility of producing Salmonella-free turkeys.

The feasibility of producing salmonella-free turkeys was investigated over a 5-year period. In Phase 1, a hatchery-breeder flock operation was monitored extensively for 4 years. Hatching eggs from a primary breeder over this period (1978-81) resulted in salmonella-free day-old poults from which 7500 hens and 600 tons were selected for breeders each of the 4 years. Approximately 2.5 million poults were produced over the 4 years. Salmonella arizonae was isolated from the hatchery debris over a 2-week period in 1980. The pelleted feed contained no animal protein products except fish solubles. A sample of feed from each delivery was cultured with no salmonella isolations. Environmental samples of dust and litter remained negative for salmonella. Phase 2 involved monitoring seven grow-out flocks initiated with salmonella-free poults with extra precautions directed at the feed and environment. The intestinal tracts of five of seven flocks at the time of marketing were negative for salmonella. Phase 3 involved a primary breeder-hatchery that had a 10-year history of S. sandiego infection in its breeder flocks and poults. A vaccination program using an autogenous oil-adjuvant bacterin supplementing other sanitation and management efforts resulted in elimination of S. sandiego. Because the breeder went out of business, it was not possible to determine if the freedom from salmonella could be sustained over a period of years.

Use of membrane proteins from Salmonella gallinarum for prevention of fowl typhoid infection in chickens.

Outer membrane protein isolated from Salmonella gallinarum was examined at different concentrations with or without a mineral-oil adjuvant for its immunogenicity and protection against live challenge. A formalin-killed whole-cell bacterin of the same organism was used for comparison. The results suggested that membrane proteins from S. gallinarum give better protection than formalin-killed whole-cell bacterin. Addition of an oil adjuvant to the protein appeared to increase the efficiency of the vaccine. When protein was given to chickens at 400 micrograms/100 g of live body weight, it produced 100% protection against oral challenge with S. gallinarum.

Phage-typing system for Salmonella hadar of animal origin.

A phage-typing system for Salmonella hadar was developed. Fifteen phages isolated from untreated sewage were used to phage-type 55 isolates of S. hadar recovered from avian and other animal species. Twenty-four distinct phage types of S. hadar were established based on lysis patterns. Methods involved in the isolation for bacteriophages for a particular serotype and the importance of bacteriophage typing is discussed in the context of the importance of S. hadar.

Gentamicin and bacterial culture (Nurmi culture) treatments either alone or in combination against experimental Salmonella hadar infection in turkey poults.

The effect of three treatments on Salmonella hadar infection in turkey poults was examined. The three treatments were: (A) a single injection of gentamicin, (B) peroral treatment with anaerobic culture derived from cecal contents of an adult turkey (Nurmi culture), and (C) combination of treatments A and B. Nurmi culture was significantly more effective than gentamicin treatment. Nurmi culture along with gentamicin reduced the number of shedding birds, but a higher proportion of birds became carriers compared with the groups given Nurmi culture only. Gentamicin injection alone did not prevent the spreading of infection in larger groups raised on litter, but it did so in one experimental group raised on wire floor.

Effects of the evisceration and cooling processes on the incidence of Salmonella in fresh dressed turkeys grown under Salmonella-controlled and uncontrolled environments.

In July and December 1981, turkeys grown in a Salmonella-free environment were sampled at the end of the slaughter and evisceration processes to determine the effect of slaughter and evisceration on the incidence of Salmonella in raw, eviscerated turkeys. A total of 109 eviscerated turkeys from the Salmonella-free flocks and 79 control turkeys were sampled. A total of 75 environmental swab samples and 5 chiller water samples were collected. Less than 1% of the eviscerated Salmonella-free turkeys were Salmonella positive and 6.3% of the eviscerated control turkeys were Salmonella positive. The results of the swab samples indicated generally good processing equipment sanitation.

Effect of ammonia on the quantitative clearance of Escherichia coli from lungs, air sacs, and livers of turkeys aerosol vaccinated against Escherichia coli.

Turkeys were given an aerosol vaccine to determine their ability to clear a virulent inhaled pathogenic strain of Escherichia coli, while they were being maintained in the presence of atmospheric NH3. Turkeys were exposed to 2 concentrations of NH3 (10 and 40 microliters/L of air). More E coli was found in lungs, air sacs, and livers of turkeys exposed to NH3. Turkeys not exposed to NH3 had better clearance of E coli. Vaccination against E coli improved the rate of clearance of E coli in birds not exposed to NH3.

Scanning electron microscopic studies of adverse effects of ammonia on tracheal tissues of turkeys.

Effects of 10 and 40 microliter of NH3/L of air (10 and 40 ppm) on the tracheal tissues of turkeys were examined under the scanning electron microscope. Turkeys maintained in the presence of either level of NH3 had deterioration of their normal mucociliary apparatus after prolonged exposure. Excessive mucous production, matted cilia, and areas of deciliation in the tracheal tissues were detected in birds exposed to NH3 concentrations as low as 10 microliters/L. The tracheal tissues of birds not exposed to NH3 appeared normal. The implications of respiratory tract damage caused by NH3 are discussed.

Use of two vaccines (live G30D or killed RW16) in the prevention of Salmonella typhimurium infections in chickens.

Several properties of a galactose epimerase mutant strain (G30D) of Salmonella typhimurium were investigated in white leghorn and white rock chickens. More chickens shed G30D when it was administered orally at 1 day of age than when given at 1, 2, or 4 weeks of age. In another experiment, the mean cumulative data obtained for 52 days on the shedding rate of virulent RW16 in the unvaccinated challenged controls were significantly higher (P less than 0.05) than data in challenged groups that had been vaccinated subcutaneously with live G30D. In a third experiment, chickens vaccinated twice with live G30D or killed RW16 were less likely to shed RW16 than unvaccinated controls following challenge with live RW16. Vaccination with both live G30D and killed RW16 was significantly more beneficial (P less than 0.05) than using either vaccine alone twice. The route of administration of the vaccines made no difference in the reduction of shedding.

Identification and isolation of somatic pili from pathogenic Escherichia coli of turkeys.

Transmission electron microscopy was performed to identify the presence of somatic pili on Escherichia coli pathogenic to turkeys. Three common pathogenic serotypes of E coli (Ola, O2a, and O78) were used. They were cultured in tryptic soy, veal infusion, and Minca medium broth and were incubated at 37 C with and without CO2 (5%). The cultures were examined for the expression of pili after 24, 48, and 72 hours of incubation. Pili were on all strains of the 3 serotypes examined. These pili were also isolated and purified.