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Biomedical subjects

R M Kenney

Publications and source records attributed to R M Kenney.

At least 55 records · Page 3Linked to original sources

Evaluation of cellulose acetate/nitrate filters for the study of stallion sperm motility.

Stallion semen was diluted in a Hepes-supplemented buffer (CM) (10(6) spermatozoa/ml) and placed in the upper well of a Sykes-Moore chemotaxis chamber. Chambers were incubated in a humidified atmosphere (5% CO2 in air) at 37 degrees C for 1 and 2 h and spermatozoa were allowed to swim through filters with a mean pore size of 3,5 or 8 micron. Spermatozoa entered filters of all three pore sizes. Distance travelled was greater for each increase in pore size (P less than 0.01) but did not differ (P greater than 0.05) between 1 and 2h of incubation. Extended semen from stallions of different fertility was analysed for the minimal concentration of spermatozoa needed to enter filters with a 3 micron pore size. Sperm progression into the filter reflected the motility of the ejaculate. Assuming that sperm motility is a good indicator of fertility, this method may be useful for estimating the fertility of a stallion. Progression of spermatozoa into filters with a pore size of 3 micron was hampered by supernatants from overnight cultures of Streptococcus zooepidemicus and Enterobacter aerogenes. Motility decreased after 2h of incubation in supernatant from S. zooepidemicus diluted 1:5 and E. aerogenes supernatant diluted 1:5 and 1:10 in culture medium. In contrast, the bacterial supernatants were chemokinetic to horse neutrophils and did not affect their viability.

Animals↗

Effect of estradiol and progesterone on antistaphylococcal activity of neutrophils from ovariectomized mares.

Neutrophils isolated from jugular blood of ovariectomized mares were studied for the effect of estradiol and progesterone on bactericidal activity against Staphylococcus aureus. In experiment 1, neutrophils obtained from 4 mares were tested for bactericidal activity by adding estradiol (43 pg/ml) or progesterone (6.4 ng/ml) to the bactericidal assay. In experiment 2, 3 of the 4 ovariectomized mares were given 2 mg of estradiol, IM, daily for 3 days. Eighteen days after the initial estradiol injection, mares were given 300 mg of progesterone, IM, for 6 days. Neutrophils from these mares were tested for bactericidal activity 4 days after the initial estradiol injection, 17 days after the initial estradiol injection (control), and 7 days after the first progesterone injection. Bactericidal activity was measured at 30 and 120 minutes by counting the number of colony-forming units remaining. Neutrophil antistaphylococcal activity was not altered by adding estradiol and progesterone to the assay or by supplementing ovariectomized mares with estradiol and progesterone (P greater than 0.05).

Animals↗

Effect of timing of progesterone administration on pregnancy rate after embryo transfer in ovariectomized mares.

Ovariectomized recipient mares were divided into two groups. Group A mares received 300 mg progesterone in oil i.m. daily starting 5 days before transfer of a 7-day embryo. Group B mares received the same dose of progesterone, but starting at least 4 days before donor ovulation. Presence of an embryonic vesicle was determined by ultrasonography; mares were considered to be pregnant if they had normal vesicle development to Day 18. Pregnancy rates were: Group A, 6/8; Group B, 1/12 (P less than 0.01). An additional 4 mares in Group B had a vesicle visible at 14 days which degenerated or did not grow. These results indicate that, for establishment of pregnancy after embryo transfer, there is a need for synchrony of donor ovulation with onset of progesterone administration to ovariectomized recipient mares.

Animals↗

Novel environment suppression of stallion sexual behavior and effects of diazepam.

Pony stallions were given sexual behavior trials in experimental "home" and "novel" environments, similar in all major features except location. In the novel environment, erection latency was increased and erection time decreased. Treatment with an anxiolytic benzodiazepine derivative (diazepam) appeared to block these effects.

Animals↗

Evaluation of androgenized mares as an estrus detection aid.

Ten pony mares that had developed stallion-like sexual behavior as the result of anabolic steroid treatment (boldenone undecylenate, 0.55 mg/kg intramuscularly (i.m.), once weekly for 12 injections) were evaluated for ability to aid in detecting estrus in cycling mares. In across-the-fence estrus detection trials, androgenized mares failed to elicit signs of estrus or diestrus. In 10-min pasture trials, in which each androgenized mare was placed in a group of 10 cycling mares (six of which were estrous), seven of the 10 androgenized mares elicited estrous behavior from one or two mares. Observations of the 10 androgenized mares among a pasture group of 21 cycling mares indicated that approximately one third of the mares in estrus could be identified on the basis of their response to androgenized mares.

Journal Article↗

Use of altrenogest to prepare ovariectomized mares as embryo transfer recipients.

Altrenogest was administered to ovariectomized mares to determine if treatment would enable establishment and maintenance of pregnancy after transfer of a 7-d embryo. Three different treatment regimens were used: Group A received 22 mg altrenogest daily starting 5 d before transfer, Group B received 66 mg altrenogest daily starting 6 days before transfer, Group C received 300 mg progesterone in oil intramuscularly daily starting 5 d before transfer. Intact, ovulation-synchronized recipients were used as controls for transfer technique. Pregnancy rates were 1 6 , 2 6 , 2 5 , and 13 19 for Group A, Group B, Group C, and controls, respectively. The pregnancy rate in Group A was significantly different from controls and Group A mares had poor uterine and cervical tone. These results show that ovariectomized mares treated with altrenogest are capable of establishing pregnancy after embryo transfer. Treatment with 22 mg altrenogest appears to be insufficient for optimal pregnancy rates after transfer in ovariectomized recipients.

Journal Article↗

Conditioned suppression of sexual behavior in stallions and reversal with diazepam.

Sexual behavior dysfunction unaccompanied by detectable physical or endocrine abnormality is an important cause of reproductive failure among domestic stallions. Several authors have suggested that such dysfunction may be psychogenic, related to negative experience associated with intense handling and training. An experimental model of experience-related dysfunction was developed by exposing pony stallions to erection-contingent aversive conditioning. This resulted in rapid, specific suppression of sexual arousal and response similar to spontaneously occurring dysfunction. Subsequently, treatment with a CNS-active benzodiazepine derivative (diazepam) reversed these effects.

Animals↗

A comparison between cervical dimensions of pregnant and nonpregnant Santa Gertrudis and Bos taurus cows.

Cervical measurements were recorded on palpation per rectum for 603 Bos taurus , Santa Gertrudis, and crossbred cattle. Postmortem cervical measurements were recorded for 77 of these cows. Antemortem measurements were positively correlated with those taken at postmortem examination (cervical diameter: r=0.75, P<0.01 and cervical length: r=0.29, P<0.06). Cervical diameters from antemortem and postmortem specimens were greater in Santa Gertrudis cattle than in Bos taurus and crossbred cattle (P<0.05). Cervical shape was different between Santa Gertrudis cattle and Bos taurus or crossbred cattle (P<0.01), with Santa Gertrudis cows having a higher incidence of conical shaped cervices than other breeds. Within Santa Gertrudis cattle, the incidence of conical cervical shape increased with age (P<0.05). Conical cervical shape was associated with a lower pregnancy rate in all breeds (P<0.01). Within Santa Gertrudis cattle, conical cervical shape was associated with a lower pregnancy rate in 1- to 4-year-old cows (P<0.05) but not in cows more than 4 years of age (P>0.05).

Journal Article↗

Microcomputer interpretation of red blood cell panels.

The interpretation of red blood cell panels and identification of alloantibodies can be a difficult and time-consuming task. PANEL-IZER, a computer program that performs this interpretation, is described. The panel analysis is based on a matrix algebra algorithm that is presented in detail. Conditional probability logic supplements the analysis by searching for unexpected reactive cells or other possibilities such as the presence of autoantibodies or antibodies to low- or high-frequency antigens. The program considers phases of reactivity, dosage effects, and reaction strengths to aid in antibody identification. Probability levels for antibody identification based on Fisher's "exact" method are calculated. The program also can help suggest a "select cell" panel. This program can be a valuable tool in blood banks to aid in the interpretation of panels, to check technologists' interpretations, to generate "select cell" panels, and to help teach students and residents antibody identification.

Blood Group Antigens↗

Photomicrographic evaluation of stallion spermatozoal motility characteristics.

A photomicrographic method for evaluation of stallion spermatozoal motility was developed, and spermatozoal image and velocity characteristics were defined. The photomicrographic method was compared with visual estimation of motility in the same semen sample over time. Using photomicrography, velocities and percentages of individual spermatozoal image characteristics were determined. Although there was a high correlation between results of the 2 methods, results of the photomicrographic method were more repeatable than were those of the visual method.

Animals↗

Infertility due to foreign objects in the cervix of a cow.

Two fetal claws were removed from the cervix of a Holstein cow that had a chronic vulvar discharge. The cow had calved 1 year earlier. After removal of the claws, localized peritonitis developed and the cervix remained open and draining.

Animals↗

Unilateral hydrosalpinx and absence of the infundibulum in a mare.

Both ovaries and associated oviducts were removed from a mare via colpotomy. The right oviduct was greatly enlarged and filled with fluid. No infundibulum could be identified; rather, the blind distended end of the oviduct adhered to the ovary at the ovulation fossa. Two cysts were attached to the exterior of the oviduct a few centimeters from the fossa. Histologic examination of the oviduct and cysts revealed a dilated lumen, a decreased infolding of the wall into the lumen, and a lack of a defined muscle layer. Congenital absence of the infundibulum resulting in a blind ampullar terminus is proposed as the cause of the hydrosalpinx.

Journal Article↗

Surgical repair of the lacerated cervix in the mare.

Surgery was performed to repair lacerations which prevented cervical closure in thirteen mares. All lacerations involved the portion of the cervix that protrudes into the vagina. There did not appear to be a predisposition for lacerations to occur in any one position about the perimeter of the cervix. Nine mares had one laceration and four mares had two lacerations. Although the lacerations were presumed to have occurred at parturition, they apparently were not associated with dystocia. The method of surgical repair is described. Eight mares were bred after surgery, and five conceived.

Journal Article↗

Antibacterial activity of mare uterine fluid.

Luminal fluid from the mare uterus was used to investigate its relation to antibacterial defenses. Uterine flushings were collected at Day 3 of estrus, Day 8 postovulation and Day 15 postovulation. Uterine proteins were concentrated by ultrafiltration, dialyzed and examined for chemotactic activity to neutrophils and for antibacterial properties. Serum taken at the time of flushing was dialyzed and studied in a similar manner. Neutrophil migration in response to serum from Day 3 estrus and Day 8 postovulation was increased (P less than 0.05) above controls. Uterine protein from Day 8 postovulation and from Day 3 of estrus also stimulated neutrophil migration (P less than 0.05) above values of controls. Antibacterial activity was measured by incubation of S. zooepidemicus with concentrated uterine flushing or serum. Serum from all three estrous cycle intervals diluted 1:10 or used at a protein concentration equal to the protein concentration of uterine fluid did not inhibit growth. After 4 h of incubation, bacterial growth in estrous serum was significantly greater (P less than 0.01) than serum taken at Day 8 and Day 15 postovulation. Uterine flushings from Day 8 postovulation significantly decreased bacterial colony-forming units (P less than 0.01). Heating flushings at 56 degrees C for 30 min did not abolish the antimicrobial activity, while heating flushings for 30 min at 80 degrees C removed this activity. The antibacterial activity does not appear to be due to agglutinating antibody.

Animals↗

Giant-cell tumor-like proliferation associated with a papillary transitional cell carcinoma of the renal pelvis.

A 56-year-old man with painless hematuria was found to have a papillary transitional cell carcinoma of the renal pelvis with an accompanying nodule composed of multinucleated and mononuclear cells, resembling a giant cell tumor of bone. The nodule was well demarcated from the carcinoma and most likely represents a response to hemorrhage into a cystic cavity. A classification composed of four groups is proposed for extraosseous tumors having features resembling giant cell tumors of bone. This grouping should help in predicting prognosis and avoid the overdiagnosis of sarcoma or undifferentiated carcinoma.

Carcinoma, Papillary↗

Effect of stage of cycle, sampling frequency and recovery of micro-organisms on total protein content of mare uterine flushings.

Mares with sound reproductive tracts were divided into two groups. In Group I (N = 12), uteri were flushed once per oestrous cycle during alternate cycles while in Group II (N = 8) mares were flushed twice in a cycle for 2 contiguous cycles. Total protein concentrations and total recoverable protein of uterine flushings taken on Day 3 of oestrus and Day 8 after ovulation in each of the 2 groups and between the 2 groups did not differ significantly. The length of oestrus and dioestrus was not affected by the flushing procedures. Total recoverable protein and total protein concentrations of flushings were higher at Day 3 of oestrus and Day 8 and 15 after ovulation (P less than 0.01) when a micro-organism was isolated from the uterus before flushing.

Animals↗

Comparison of uterine protein content and distribution of bacteria in the reproductive tract of mares after intrauterine inoculation of Haemophilus equigenitalis or Pseudomonas aeruginosa.

Two groups of 3 mares were inoculated with Haemophilus equigenitalis or Pseudomonas aeruginosa on the 1st day of estrus. Uterine flushing samples were recovered on day 3 of estrus and day 8 after ovulation for each cycle. Mares were killed 22, 25, and 30 days after inoculation with P aeruginosa and 45, 46, and 49 days after inoculation with H equigenitalis. Pseudomonas aeruginosa was recovered from the uterus of 2 mares 48 hours after inoculation. Although the initial flushing sample of 1 of these 2 mares had an increased total protein concentration, there appeared to be little difference between protein concentrations of other uterine flushing samples. Haemophilus equigenitalis was recovered from the uterus of each of the 3 mares at postmortem. One mare had a slight, purulent discharge from the vulva. Total protein values were not increased in flushing samples from this mare after inoculation with H equigenitalis. Total protein values decreased in the last flushing sample of each of the 2 remaining mares. Swabbing the uterus was more effective than was homogenizing the uterine mucosa in isolating H equigenitalis.

Animals↗

Chemotactic properties and protein of equine uterine fluid.

Forty uterine fluid samples were obtained from 4 mares classified as resistant to uterine bacterial infection. The uterus of each mare was flushed with 50 ml of saline solution during estrus and diestrus of successive estrous cycles. Bacteria or fungi were isolated from 4 samples, and 7 additional samples were obtained from a mare with active intrauterine infection. Fluid volumes obtained during estrus (means = 40.3 +/- 11 ml) tended to be greater than those recovered during diestrus (means = 36.8 +/- 7.9 ml), but the difference was not significant. Concentrations and yields of protein in recovered fluid did not vary significantly with the day of the estrous cycle. Protein concentration was significantly increased in samples from the infected uterus (P = less than 0.001). The ability of uterine fluid samples to attract neutrophils was measured using chemotactic chambers. There was no significant difference between distances migrated by neutrophils toward fluids obtained during estrus or diestrus. Chemotaxis scores tended to be higher with samples from the infected uterus, and the difference was significant for samples from 2 mares. Chemotaxis was neither significantly correlated with protein concentration of uterine fluid, nor with serum estrogens or progesterone.

Animals↗