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PubMed2024

Decoding the trajectory of antibiotic resistance genes in saline and alkaline soils: Insights from different fertilization regimes.

The soil salinity and alkalinity play an important role in the occurrence and proliferation of antibiotic resistance genes (ARGs). Yet, little is known the underlying mechanism by which soil salinity and alkalinity affect antibiotic resistance evolution. Here we investigated the ARGs variation in soil salinity and alkalinity environments created by different fertilization, and explored the biological mechanisms that salinity and alkalinity alter the evolutionary paradigm of antibiotic resistance. The results showed the soil treated by organic fertilizer exhibited a low salinity, neutral level (TSD 239.20 μS/cm, pH 7.17). The ARG abundance in the OF treatment was the highest, keeping an average of 67.83 TPM. Beside the effect of direct input of organic fertilizer at the beginning, it was important to note that, ARGs abundance during planting showed significant correlations with pH and electric conductivity. We observed that changes in microbial survival strategies under different salinity and alkalinity conditions further affected ARG hosts abundance. Indoor experiments demonstrated that there was a survival trade-off between the growth of resistant bacteria and the evolution of antibiotic resistance in salinity and alkalinity environments. Meta-genomic and Meta-transcriptomic analysis consistently demonstrated bacterial antibiotic resistance was primarily associated with pyruvate, energy and lipid metabolic pathways. The functional gene related to salinity and alkalinity, like cysH, cysK, plsB and plsC showed negative correlations with MDR. Prokaryotic transcription assays validated these relations. This study well explains the prevalence of soil ARGs after different fertilization regimes and will give a deeper understanding for the effect of soil salinity and alkalinity on antibiotic resistance evolution.

Soil↗
PubMed1978

[Biotechnical increase of litter size in early pregnant sows using steroid application. 1. The effect of a single application of hydroxyprogesterone capronate on fertility response in ovulation-synchronized gilts and old sows].

One single intramuscular injection of hydropyrogesteroncapronate was given in an experiment to 199 gilts and 239 old sows on the 13th or 15th or 17th day after insemination to test various fertility performance parameters. Doses were 50 mg, 75 mg or 100 mg. Positive effects on litter size were established from the majority of nine compared experimental variants. The number of live-born piglets was increased up to two. Several groups of gilts had higher mean litter weights. More studies are necessary to prepare an adequate therapeutic regime by which to reduce loss of embryos in swine.

Age Factors↗
PubMed1977

[Effect of continuous illumination on the reproductive function in rats. Aftereffects].

The continuous illumination of 2 months old Wistar rats during 1,2 and 6 months resulted in the appearance of permanent oestrus in 24, 61 and 100% of animals, resp. The weight of newborn rats from the females illuminated during pregnancy was by 7% higher than in the control. The continuous illumination during 1 month prior to mating did not affect the embryogenesis. The weight of 20 days old rats from the females illuminated during 1 month (prior to mating), 2 months (prior to mating + + pregnancy) and 6 months exceeded that of the control ones by 5, 18 and 30%, resp. The increase in the weight of rats persisted in the next reproductive cycle in spite of the standard conditions of light regime (14 hrs day: 10 hrs night).

Animals↗
PubMed1976

[Hormonal methods of increasing fertility in swine].

Experiments were carried out to raise the conception rate in sows during the summer season under industrial conditions of breeding. Eight test groups of 365 animals were formed as well as four control ones with 137 pigs. The sucking period lasted 28 to 33 days. When in estrus the sows were mated with boars twice at a 24-hour interval. In five groups that were dried up from July to September was recorded the effect of several kinds of gonadotropic hormones administered alone or in combination with vitamin E and steroid hormones -- Gravohormone Tolligon, an oil emulsion of PMS (500 IU), with 250 Chorulon and 2 mg estradiol benzoicum; an oil solution of PMS (500 IU) with 2 mg estradiol, 25 mg testosterone and 30 mg vitamin E. During the same period three other groups of test sows were formed to use steroid hormones such as Gravignost, an oil solution of 2 mg estradiol benzoicum, and 40 mg testosterone propionate as well as the same preparation in combination with 30 mg vitamin E. The deterioration of the temperature and humidity regime in the summer at the industrial pig-breeding complexes was shown to inhibit the manifestation of estrus and lower the conception rate in sows. Either alone or in combination with vitamin E and estradiol the gonadotropic hormones largely raised the per cent of animals manifesting estrus for ten days in summer after weaning their piglets (89 to 100 per cent) as well as the number of lively born offsprings per sow (9.8 to 11.3). The optimal doses used were as follows: Gravohormone, 13--14 IU/kg liveweight; Folligon or PMS, 6--7 IU per kg; and choriogonadotropin at the rate of 500 IU per sow. One the other hand, the steroid hormonal preparations bring about estrus of a lower quality leading to a low conception rate and fertility at first insemination, disturb the sexual cyclicity. They should not be administered alone as cycle starters in pig-breeding.

Animals↗
PubMed1979

Some aspects of feeding of brood gilts and sows.

The amounts of feed required during each of the reproductive phases are graphically illustrated and supported by specific recommendations where possible with discussion of the underlying rationale and of the often conflicting considerations. For flushing, an increase of 50 to 100% of energy requirements above maintenance level is recommended, supplied, for example, by one to two kg maize extra per day during the week before expected oestrus, in order to increase the ovulation rate. During pregnancy a constant feeding level is proposed 2.2 to 2.5 kg of feed with 8.8 MJ of nett energy/kg and 12% digestible crude protein being necessary. Two days before farrowing the feeding level must be lowered and steps taken to keep the gut contents to a minimum. During lactation the feed has to contain 8.8 MJ nett energy/kg and 14% digestible crude protein and the intake reduced by 10 to 20% in the case of early weaning. At weaning a fasting regime is suggested to effect physiological stress. The relation between feeding level during pregnancy and the mass gain of the sow asnd number of piglets born, as well as on the birth mass of the piglets, and the relation between N intake and N retention and litter mass oat birth are shown graphically.

Animal Husbandry↗
PubMed1978

Midtrimester abortion utilizing intraamniotic prostaglandin F2alpha, laminaria and oxytocin.

The combined use of 40 mg of intraamniotic prostaglandin F2alpha, followed immediately by the insertion of one or more laminaria tents, and of a high-dose oxytocin infusion of 166 milliiunits per minute is a safe, effective, and efficient regime for midtrimester abortion. In 100 consecutive patients between 16 and 20 weeks of gestation, no failures occurred. The mean injection-abortion time was 15.7 hours. Six patients required the reinjection of 20 mg of prostaglandin F2alpha at 24 hours. The placenta was removed with instruments after four hours in 19 patients and done electively in seven patients in less than four hours. Physician-patient contacts were minimized, for all the abortion-initiating techniques were accomplished concomitantly, as opposed to regimes with laminaria pretreatment, or deliberately staggered prostaglandin injections were used. Most of the patients were able to be discharged after one day in the hospital. Thus, the patients' inconvenience and expense were minimized, with no sacrifice in safety.

Abortion, Induced↗
PubMed1978

Midtrimester intra-aminotic administration of prostaglandin F2alpha in combination with an hyperosmolar urea solution: effect upon plasma levels of estradiol, progesterone, and human placental lactogen (HPL).

A study was undertaken in order to investigate the clinical observation that patients who underwent midtrimester abortion using intra-amniotic PG F2alpha in combination with hyperosmolar urea, always aborted a dead fetus. Ten Caucasian primigravidae, aged between 16 and 22 years old and whose pregnancies ranged between 14 and 23 weeks in duration, were studied. The patients were randomly divided into two equal groups. The one group received urea and PG F2alpha intra-amniotically whereas the other received PG F2alpha alone. Blood was drawn for measurement of plasma estradiol, progesterone and human placental lactogen (HPL) prior to injection of the abortifacients and at regular intervals thereafter for a period of 120 min. The five patients who received the combination regime of treatment (urea + PG F2alpha) showed a rapid decline in the plasma concentrations of these hormones and induction of abortion was followed by fetal death within 35 min in all cases. In contrast, the five patients who received intra-amniotic PG F2alpha alone, did not (with a single exception), demonstrate this rapid decline in the plasma concentrations of the placental hormones measured. Also with the same single exception, these fetuses, although stillborn, were alive two hours after inducing abortion.

Abortion, Induced↗
PubMed1979

Ovulation rate and egg recovery in cattle treated repeatedly with pregnant mare serum gonadotrophin and prostaglandin.

Fourteen heifers were superovulated five to 10 times using pregnant mare serum gonadotrophin (PMSG) and prostaglandin in a standardised regime which resulted in a mean interval of 42.1 days (SEM +/- 0.97) between treatments. There was a significant (P less than 0.02) fall in the mean ovulation rate at the second treatment when compared with the first but no significant difference between mean ovulation rate at the second and subsequent treatments. No significant difference between treatments in mean egg recovery rate or in the percentage of normal eggs recovered was demonstrated. Four heifers treated 10 times continued to respond with multiple ovulations on most occasions. At the end of the experiment 13 of the 14 heifers were inseminated and 12 conceived, requiring a mean of 1.67 services per pregnancy.

Animals↗
PubMed1978

Responses of nonhuman primates to a polybrominated biphenyl mixture.

In a series of experiments, rhesus monkeys have been given in their diets 0.3, 1.5, and 25 ppm of a commercial polybrominated biphenyl (PBB) (as FireMaster FF-1). The seven adult female monkeys receiving 0.3 ppm PBB have been on the treatment regime for 15 months and have consumed over 22 mg of PBB. During the initial 6 months of exposure, they lost weight and 2 of the animals develop sterile abscesses. At 6 months, 4 of the 7 animals had flattened and lengthened serum progesterone peaks. This change was correlated with an increase in length of their menstrual cycles. After 6 months of PBB exposure, the animals were bred. Two of the 7 animals showed excessive and prolonged implantation bleeding. Two abortions and 5 live births were recorded. All of the experimental infants were smaller than the controls at birth. The animals receiving a diet containing 1.5 ppm PBB for 36 weeks (total intake 70 mg) have shown a moderate weight loss and decrease in serum cholesterol. Similar changes have also been recorded in the group given the 25 ppm PBB diet for 14 weeks (approximately 500 mg total intake). In addition, these animals have also developed a hyperplastic gastritis.

Animals↗