Regular or covert sex defines two lineages and worldwide superclones within the leaf-curl plum aphid (Brachycaudus helichrysi, Kaltenbach).

Asexual reproduction occurs widely in plants and animals, particularly in insects. Aphid species usually reproduce by cyclic parthenogenesis, but many species include obligate asexual lineages. We recently showed that the leaf-curl plum aphid, Brachycaudus helichrysi, actually encompasses two lineages, B. helichrysi H1 and H2. Ecological data suggest that these lineages have different life cycles. We conducted a large population genetics study, based on 14 microsatellite loci, to infer their respective life cycles and investigate their population structure and geographical distribution. Brachycaudus helichrysi H1 displayed the genetic signature of cyclical parthenogenesis, using plum trees as primary hosts for sexual reproduction, as classically described for B. helichrysi. This global survey showed that the Central Asian population of H1 was clearly differentiated from American-European populations. By contrast, B. helichrysi H2 displayed the typical signature of obligate asexual reproduction. H2 encompassed at least eight highly successful genotypes or superclones. This lack of ability to undergo sexual reproduction was confirmed for one of the superclones by sex induction experiments. We found only one B. helichrysi H2 population that underwent sexual reproduction, which was collected from peach trees, in Northern India. Our results confirm that H1 and H2 have different life cycles. Brachycaudus helichrysi H1 is clearly heteroecious using plum trees as primary hosts, while B. helichrysi H2 encompasses several anholocyclic lineages, and some heteroecious populations that until now have only been found associated with peach trees as primary hosts. We discuss implications of these findings for the pest status of B. helichrysi lineages.

Double insemination and gonadotropin-releasing hormone treatment of repeat-breeding dairy cattle.

Our objective was to determine if double inseminations during the same estrous period of dairy cattle eligible for their third or fourth service (repeat breeders) would improve pregnancy rates equivalent to injections of GnRH given at the time of AI. Repeat-breeding, lactating cows from six herds (five herds in the San Joaquin Valley of central California and one herd in northeast Kansas) were assigned randomly to four treatment groups when detected in estrus: 1) single AI plus no injection, 2) single AI plus 100 micrograms GnRH at AI, 3) double AI plus no injection, or 4) double AI plus 100 micrograms of GnRH at AI. Inseminations were performed according to the a.m.-p.m. rule. The second AI for the double AI treatment was given 12 to 16 h after the first AI. Injections of GnRH were given intramuscularly immediately following the single AI or the first AI of the double AI. Pregnancy rates of cows given a single AI and hormone injection were numerically higher in all six herds than those of their herdmates given only a single AI. In five of six herds, the pregnancy rates of cows given a double AI and hormone injection were numerically higher than pregnancy rates of their herdmates given only a double AI. Overall pregnancy rates for the four treatments were 1) 112/353 (32.1%), 2) 165/406 (41.6%), 3) 119/364 (33.5%), and 4) 135/359 (37.5%). Gonadotropin-releasing hormone increased pregnancy rates of repeat breeders compared with controls given only a single AI. No further benefit beyond the single AI was accrued from the double AI treatment, with or without concurrent hormone administration.

Effect of oxamisole on immune parameters of mice infected with murine hepatitis.

The effects of Oxamisole, 2,3,5,6,7,8-hexahydro-2-phenyl-8,8- dimethoxyimidazo[1,2a]pyridine on immune parameters of mice infected with murine hepatitis were investigated. Young Swiss Webster mice were injected intraperitoneally (i.p.) with the Friend-Braunsteiner strain of murine hepatitis virus and with various doses of Oxamisole at 48 h pre- 24 h pre-, and 4 h post-virus exposure. Antiviral activity was seen in the drug-treated mice which was approximated on the basis of 21-day survival frequency and hepatic discoloration, SGOT and SGPT levels and amount of infectious virus recoverable from the liver. On day 4 post-viral exposure, splenic cells from some of the drug- and placebo-treated cells of infected mice injected with Oxamisole, 25 mg/kg/day, produced significantly more interleukin-1 and interleukin-2 than cells of infected mice treated with saline only. Similarly, mice treated with 25 mg/kg/day of this compound had cells with significantly increased antibody-dependent cell-mediated cytotoxicity as compared with placebo treated animals. However, cells from mice treated with Oxamisole did not demonstrate altered natural killer cell activity. It is concluded that Oxamisole, when administered to mice infected with murine hepatitis virus, has antiviral properties which possibly are mediated through the immunomodulatory effects of this compound on the immune system.

Reproductive disorders in the periparturient dairy cow.

Incidence, predisposing factors, and implications of various reproductive disorders (dystocia, twinning, stillbirth, retained placenta, cystic ovaries, anovulation, infections of the reproductive tract, metritis, and abnormal health status) are reviewed as to their inter-relationships and collective impact on reproductive performance, milk yield and predisposition to other diseases or disorders in the periparturient dairy cow. All reproductive disorders reviewed reviewed reduce reproductive performance either directly or indirectly. Concurrent milk yield was reduced marginally in a few studies as a consequence of twinning, retained placenta, cystic ovaries, metritis, or other uterine disorders, and in cows with an abnormal health status. There is strong evidence for associated losses in milk yield following surgical delivery of a stillborn calf. We conclude that most periparturient disorders occur as a complex, rather than as a single abnormality. Cows with one disorders are at increased risk for other disorders, including metabolic ones. In contrast, actual milk yield or potential for high production generally does not predispose cows to increased risk for any of the reproductive disorders. The literature suggests that prophylactic measures to prevent occurrence of the one disorder might decrease the risk and incidence of other related disorders, either directly or indirectly.

Fertility of postpartum dairy cows after administration of gonadotropin-releasing hormone and prostaglandin F2 alpha: a field trial.

Our objective was to examine further the potential profertility effects of gonadotropin-releasing hormone and prostaglandin F2 alpha in postpartum Holstein cows. Reproductive performance was monitored in 843 cows milked thrice daily. One group of cows (n = 218) was untreated, while three groups received either 100 micrograms gonadotropin-releasing hormone administered once between d 11 and 25 (n = 211); 25 mg prostaglandin F2 alpha given once between d 11 and 25 (n = 215); or 25 mg prostaglandin F2 alpha given once between d 25 and 40 postpartum (n = 190). No profertility effects were detected in cows, regardless of their health status during the periparturient period, except cows given gonadotropin-releasing hormone between d 11 and 18 had shorter intervals to first estrus and to first service than controls. Cows with reproductive disorders (abnormal health status) in the concurrent lactation had longer intervals from calving to conception after receiving gonadotropin-releasing hormone between d 18 and 25 or prostaglandin F2 alpha between d 33 and 40. Abnormal health status adversely affected every reproductive trait measured. Early postpartum treatments with either hormone failed to improve reproductive performance of dairy cows, in contrast to several reports of profertility effects for gonadotropin-releasing hormone, and a few reports for prostaglandin F2 alpha.

Conception rates in repeat-breeders and dairy cattle with unobserved estrus after prostaglandin F(2) alpha and gonadotropin-releasing hormone.

In Experiment 1, cows with a history of at least two previous unsuccessful inseminations were allocated to four groups. At the repeated estrus (third or greater service), some of the cows were inseminated according to the a.m.-p.m. rule (Controls, n = 83), or received i.m. 100 mug gonadotropin-releasing hormone (GnRH, n = 32) within 30 sec after insemination. Ovaries of the remaining cows to be treated were palpated during the anticipated ensuing luteal phase to determine the presence of a corpus luteum. Cows found to have luteal tissue received i.m. 25 mg prostaglandin F(2)-alpha (PGF(2)-alpha) and were inseminated after detected estrus or at 72 and 96 h after PGF(2)-alpha in the absence of estrus. Cows given PGF(2)-alpha either received no further treatment (PGF(2)-alpha, n = 40) or were given i.m. 100 mug GnRH (PGF(2)-alpha + GnRH, n = 29) after insemination or at 72 h after PGF(2)-alpha in the absence of estrus. Conception rate of control cows (39%) was similar to that of cows given PGF(2)-alpha (40%) or PGF(2)-alpha + GnRH (43%), but it tended to be lower (P = 0.13) than that of cows given only GnRH at insemination (54%). In Experiment 2, cows with unobserved estrus and diagnosed not pregnant (palpation) were palpated to detect a corpus luteum. Cows with luteal tissue received i.m. PGF(2)-alpha (n = 52) or PGF(2)-alpha + GnRH (n = 45) and were inseminated as described above. Conception rates were similar (39% vs 33%, respectively). In Experiment 3, cows in a large commercial dairy with (n = 93) or without (n = 420) previous reproductive problems were given i.m. 100 mug GnRH after insemination (n = 169) or were left untreated (n = 344) at repeat services (third and fourth services). Treatment with GnRH improved (P < 0.05) conception in normal (47% vs 36%) and abnormal (25% vs 12%) repeat-breeding cows. Treatment with PGF(2)-alpha alone or in conjunction with GnRH failed to further improve conception rates and only delayed intervals to rebreeding when administered during the luteal phase after the repeated estrus. The use of GnRH failed to reduce intervals from treatment to insemination or improve conception in cows with unobserved estrus compared to treatment with PGF(2)-alpha alone.

Inhibition of murine hepatitis virus infections by the immunomodulator 2,3,5,6,7,8-hexahydro-2-phenyl-8,8-dimethoxy-imidazo[1,2a]pyridine (PR-879-317A).

PR-879-317A (2,3,5,6,7,8-hexahydro-2-phenyl-8,8-dimethoxy-imidazo [1,2a]pyridine) has been found to be a T-cell-selective immunomodulating agent. In the current studies, a series of experiments was designed to determine the potential antiviral activity of this compound in mice infected with murine hepatitis virus. In a comparative antiviral experiment, the activity seen was superior to that of levamisole, a known immunorestorative agent. This activity was characterized by an increase in the 21-day survival frequency, a decrease in hepatic discoloration, a decrease in the amount of infectious virus recoverable from the liver, and normalization of serum glutamic oxalacetate and pyruvate transaminase levels. A comparison of treatment routes indicated the relative efficacies as intraperitoneal greater than per os greater than intramuscular greater than or equal to subcutaneous. Alteration of the treatment schedule markedly affected the antiviral effect; prophylactic or therapeutic treatments once or twice daily for 3 days were usually effective. Single treatments begun 4 h before or 24 h after virus inoculation were highly efficacious. Three treatments administered on alternate days, beginning 48 h before virus inoculation, proved moderately effective. Thrice-daily treatments were ineffective, as were treatments with durations of greater than 3 days. The optimal dosage varied according to the treatment route and dosage schedule. When assessed for direct antiviral activity in vitro, PR-879-317A failed to demonstrate any significant activity against murine hepatitis virus. The positive in vivo activity noted might therefore be the result of immune modulation rather than a direct antiviral effect.

Effect of vidarabine in dimethyl sulfoxide vehicle on type 1 herpesvirus-induced cutaneous lesions in laboratory animals.

Vidarabine (9-beta-D-arabinofuranosyladenine) prepared in a 70% dimethyl sulfoxide vehicle was applied topically to type 1 herpesvirus-induced cutaneous lesions on guinea pigs and athymic nude mice. Treatments were 3 or 5 times daily for 7 days beginning 24 h after virus exposure. Against infections in guinea pigs induced by a thymidine kinase-positive virus strain, either treatment schedule effectively inhibited mean lesion score, lesion size, appearance of new lesions, and reduced lesion virus titers. Therapy was similarly effective against infections in guinea pigs induced by a thymidine kinase-negative virus strain, except that lesion virus titers were somewhat increased in animals treated 3 times daily. Treatment 5 times daily was most efficacious against both virus strains. Treatment 3 times daily of mice infected with a thymidine kinase-negative virus was not effective, but treatment 5 times daily significantly inhibited lesion score and size and reduced lesion virus titer by 37%. Toxicity controls exhibited no signs of skin irritation, although guinea pigs treated 5 times daily experienced some transient weight loss.

Effect of selenazofurin on influenza A and B virus infections of mice.

The inhibitory effects of selenazofurin and ribavirin on influenza A and B virus infections in mice were compared. Both compounds, when administered intraperitoneally (i.p.), reduced lung consolidation and prolonged mean day of death, but ribavirin more effectively increased survivor number and lowered lung viral hemagglutinin (HA) titers. Lung HA titers often increased in selenazofurin-treated animals. To determine the most appropriate i.p. treatment schedule, influenza A virus-infected mice were treated once, twice or thrice daily for 7-9 days, or once only. Treatment once daily for 9 days beginning 4 h pre-virus exposure, for 3 days beginning 24 h post-virus exposure, or once only 48 h post-virus exposure was most effective. Body temperature, which usually declined during infection, increased to near-normal levels in animals treated with selenazofurin, especially in animals treated a single time or for 3 days with high dose levels. Selenazofurin was well tolerated at a dose of 50 mg/kg administered twice daily, and at 400 mg/kg administered once only. Rectal temperatures temporarily declined following every other day treatment with 400 mg/kg.

Controlling first service and calving interval by prostaglandin F2 alpha, gonadotropin-releasing hormone, and timed insemination.

Our objective was to determine if calving intervals could be shortened and made less variable by using prostaglandin F2 alpha to control the occurrence of first services. Holstein cows (n = 348) were assigned at calving to four treatment groups. Control cows (n = 88) were inseminated at their first observed estrus after 40 d postpartum. Estrous cycles of the remaining cows were synchronized with prostaglandin F2 alpha to allow insemination (first services) 80 h after the second injection (n = 86), insemination at 80 h preceded by gonadotropin-releasing hormone at 72 h (n = 86), or insemination at 72 and 96 h (n = 88) after the second injection (51 to 57 d postpartum). By design, interval to first service was reduced to 57 d for treated cows (63 d for controls) and was less variable (12% of that for controls). Conception rate at first service was lower after timed inseminations than that of controls. Intervals to conception and subsequent calving were similar in all treated cows and controls. Of cows sampled, 23 of 176 (13%) failed to respond with luteolysis when progesterone in serum exceeded 1 ng/ml, and 26 of 176 (15%) had low concentrations of progesterone in serum and could not respond to prostaglandin F2 alpha. Poor response to timed inseminations may have occurred because only 72% of 176 cows sampled responded with luteolysis. When only cows observed in estrus were considered, conception rate approached that of controls (51%).(ABSTRACT TRUNCATED AT 250 WORDS)

Activity of selenazofurin against influenza A and B viruses in vitro.

Activity of the new antiviral compound selenazofurin was compared with the known active compounds ribavirin and amantadine against influenza A and B viruses. In experiments with Madin Darby canine kidney cells, selenazofurin inhibited the cytopathic effect and yield of influenza A/NWS/33 virus, with 50% effective dose ranges of 0.7 to 1.4 micrograms/ml (virus rating [VR], 1.3 to 1.4). The 50% effective dose range for ribavirin was 1.2 to 1.6 micrograms/ml (VR, 1.0 to 1.3), and for amantadine it was 9 micrograms/ml (VR, 0.9). Selenazofurin and ribavirin were similarly inhibitory to influenza B/Lee/40 virus, whereas amantadine was inactive. Selenazofurin appeared somewhat cytotoxic in these studies at concentrations as low as 1 micrograms/ml.

Stage of estrous cycle, time of insemination, and seasonal effects on estrus and fertility of Holstein heifers after prostaglandin F2 alpha.

Stage of estrous cycle, time of insemination, and season of the year were examined for their influence on estrus and fertility of 223 Holstein heifers after prostaglandin F2 alpha (treatment). Heifers treated during early stages (days 5 to 8) of the estrous cycle had shorter (by 11 h) and less variable intervals to estrus compared with treatment of heifers during late stages (days 14 to 16) of the estrous cycle. A greater proportion of heifers in the early cycle treatment (79/81, 97%) were in synchronous estrus (20-h period) after treatment compared with the late cycle treatment (71/86, 83%). Conception rates were lower when early cycle heifers were inseminated at 80 h after prostaglandin F2 alpha than when inseminated according to estrous detection and also lower as compared with late cycle heifers inseminated at 80 h. No differences in fertility were observed for late cycle heifers inseminated at 80 h compared with those inseminated according to estrous detection. Season of the year had no influence on intervals to estrus or on proportion of heifers expressing estrus after prostaglandin F2 alpha, regardless of stage of estrous cycle. Conception rate during winter, however, was higher in early but not late cycle heifers inseminated after prostaglandin F2 alpha, as compared with fall or spring. Variability of interval to estrus and of fertility after inseminations by appointment at 80 h appears to be due to stage of estrous cycle at time of prostaglandin F2 alpha treatment rather than season of the year.

Prostaglandin F2 alpha for lactating dairy cows with a palpable corpus luteum but unobserved estrus.

Two experiments in 17 dairy herds were for the effectiveness of prostaglandin F2 alpha (treatment) in reducing luteolysis and inducing intervals to conception of 308 cycling lactating dairy cows. Cows with unobserved estrus before first insemination (Experiment 1) and nonpregnant cows with unobserved estrus after insemination (Experiment 2) were eligible for treatment. Cows in Experiment 1 were assigned alternately either to an untreated control group of 85 or to a group of 138 that received 25 mg prostaglandin F2 alpha after detection of a corpus luteum by ovarian palpation. Cows were inseminated either at estrus or at 72 and 96 h posttreatment in the absence of detected estrus. Intervals from treatment to estrus, to first service, and to conception were longer for controls than for treated cows. Conception at first service was similar for controls (39%) and for treated (43%) cows. Procedures were similar for Experiment 2. Intervals from treatment to estrus and treatment to first service were longer for control cows, and treatment to conception tended to be longer for 39 controls than for 46 treated cows. Conception at first service was similar controls (52%) and treated (44%) cows. Prostaglandin F2 alpha was 91% effective for inducing luteolysis based on progesterone concentrations in blood serum. Successful treatment was dependent upon accurate diagnosis of a functional corpus luteum. Days from treatment to conception were reduced for cows with unobserved estrus if treated cows were inseminated at estrus or by appointment in the absence of detected estrus.

Gonadotropin-releasing hormone and conception of Holsteins.

Effects of gonadotropin-releasing hormone (100 micrograms) and time of artificial insemination on fertility, were examined in lactating dairy cows at first, second, and third services. Inseminations were either soon after detected estrus (0 h) or 12 h later, and cows were given gonadotropin-releasing hormone or saline after inseminations. Conception at first service was not improved by hormone treatment. But conception rates at repeat services were improved by nearly 21% when cows were treated with gonadotropin-releasing hormone within 30 s after insemination. Inseminations soon after detection of estrus (0 h) followed by hormone treatment resulted in the highest conception rates for all services. Time of the insemination (0 versus 12 h) had no effect on conception. Administering gonadotropin-releasing hormone at repeat services should improve conception rate of lactating dairy cows.

Nontraumatic suppurative mediastinitis presenting as acute mediastinal widening.

A case of acute nontraumatic suppurative mediastinitis in a 56-year-old man is presented. The patient was admitted with signs and symptoms of a left lower lobe pneumonia and acutely developed mediastinal widening on chest radiograph. A mediastinal abscess was drained by posterior mediastinotomy after a complicated hospital course. Mediastinitis is a rare complication of pneumonia. It is a serious condition, requiring prompt diagnosis and aggressive therapy, and should be considered in the differential diagnosis of acute mediastinal widening.

Earlobe type, race, and age: effects on earlobe creasing.

There has been much discussion of the utility and validity of the earlobe crease as a warning sign of cardiovascular disease. The authors postulated that the mixed findings were due to the neglect of three variables: age, race, and earlobe shape. Age and earlobe shape were studied in 324 healthy adult subjects from three racial groups: southwestern Alaskan Eskimos (70), Navajos (167), and whites (87). It was found that creases develop with age in healthy adults, that creasing is related to earlobe shape, that the age of onset of creasing varies according to race, and that the frequencies of occurrence of different earlobe shapes differ by race. Future studies of earlobe creases should therefore include the variables of age, race, and earlobe shape.

Factors affecting reproductive performance of dairy cows first inseminated after five weeks postpartum.

Various factors influencing reproduction of 307 Holstein cows were evaluated. Sources of variation of several measures were estrous certainty, time of day of detected estrus and insemination, method of thawing semen, ease of cervix penetration, presence of clear mucus at insemination, service number, service sire, inseminator, age of cow, maximum ambient temperature on the service date, and milk yield. Interval to first service of older cows was longer than of younger cows and shorter for cows with higher milk yield. Conception rate was higher for inseminations before noon than after noon and tended to be lower at inseminations when milk yield was at the extremes (low or high). Rate of conception was similar for cows whether inseminated at early or later postpartum intervals. More services were required by cows that were inseminated when milk yield was at the extremes (low or high). Fewer days open were associated with fewer total services and younger age at conception. Cows inseminated with semen thawed in hot (65 degrees C, 7 to 10 s) or warm (35 degrees C, 30 s) water conceived earlier postpartum than did those inseminated with semen thawed in the cow. Submitting cows for insemination after detection of standing estrus, mounting activity, or less certain symptoms of estrus had no adverse effect on fertility or days open.

Estrous intensity and conception rates in Holsteins.

During 34 mo, 732 inseminations were evaluated in Holstein cows and heifers of breeding age. Females were submitted for insemination after detection of either 1) standing estrus, 2) mounting activity, or 3) other subtle symptoms of estrus (clear mucus, general appearance of genitalia or tailhead, and excessive vocalization). Conception rates were similar following standing estrus and mounting activity (50 versus 46%). Although higher conception rates occurred following standing or mounting activity than after detection of subtle estrous symptoms, one of three inseminations resulted in conception after insemination in the latter group. Clear mucus in half of the females upon cervical manipulation at insemination was associated with higher conception. Service number, age, and maximum ambient temperature on day of insemination also affected conception rates. Methods of thawing semen, ease of cervix penetration at insemination, service sire, inseminator, and time of estrous detection and insemination had little effect on fertility. Acceptable conception rates were achieved with more liberal interpretation of estrous symptoms.