Home About us Contact | |||
Parental Male (parental + male)
Selected AbstractsTwo-generation reproductive toxicity study of inhaled tertiary amyl methyl ether (TAME) vapor in CD® ratsJOURNAL OF APPLIED TOXICOLOGY, Issue 6 2003R. W. Tyl Abstract Under Of,ce of Prevention, Pesticides and Toxic Substances draft guidelines, CD® weanling F0 rats (30 of each gender per group) inhaled tertiary amyl methyl ether vapor at 0, 250, 1500 or 3000 ppm 5 days a week and 6 h a day for 10 weeks, with vaginal cytology evaluated for weeks 8,10. The F0 animals then produced F1 offspring, with exposure 7 days a week from mating through to lactation. During the F1 prebreed exposure period, vaginal patency, preputial separation (PPS) and vaginal cytology were evaluated. The F1 animals were mated, with F2 anogenital distance measured on postnatal day zero. At F2 weaning 30 of each gender per group were selected for postwean retention, with no exposures, through vaginal patency and PPS. Body weights, feed consumption and clinical signs were recorded throughout the study. Adult F0 and F1 systemic toxicity was present at 1500 and 3000 ppm. Minor adult male reproductive toxicity was present at 3000 ppm. There were no adult effects on vaginal cyclicity, estrous cycle length, mating, fertility, pregnancy, gestational length or ovarian and uterine weights. There were no treatment-related gross or histopathologic ,ndings in parental male or female systemic or reproductive organs. The F1 and F2 offspring toxicity was present at 1500 and 3000 ppm. The no-observable-adverse-effect level for adult systemic and offspring toxicity was 250 ppm and 1500 ppm for male reproductive toxicity (females at >3000 ppm). Copyright © 2003 John Wiley & Sons, Ltd. [source] Genetic life history effects on juvenile survival in bluegillJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2007B. D. NEFF Abstract Foraging behaviour under the risk of predation has important consequences on an individual's survivorship and fitness. In bluegill (Lepomis macrochirus), we have recently shown that offspring sired by males of alternative life histories differ in their foraging behaviour. Specifically, offspring sired by ,cuckolder' males take fewer risks during foraging than do offspring sired by ,parental' males. This behavioural difference can have important consequences on the fitness of the two life histories and thus the underlying evolutionary mechanism. Here, we examine the consequences of this behavioural variation on growth rate, condition and survivorship during early development of juveniles. We used split in vitro fertilization to generate maternal half-sibs that differed in sire life history. The resulting 18 455 larvae from 50 families were released into a microcosm with safe and risky foraging areas for approximately 2 months. A total of 262 juveniles (1.4%) survived of which parentage was unambiguously determined using microsatellite genetic markers for 254 (97%). Although we found significant dam effects, there was no difference in apparent growth rate or condition of juveniles sired by males of the two life histories. Of the 25 paired half-sib families, 15 had higher survivorship when sired by a cuckolder male, seven had higher survivorship when sired by a parental male and three had no surviving offspring from either sire. Thus, although growth was similar between the two offspring types, survivorship was not. Combining the differential survivorship estimate with paternity data from natural nests and the frequency of males adopting each life history, we calculated that the cuckolder life history has 1.87 times higher fitness than the parental life history. As such, the life histories likely are not governed by a genetic polymorphism. [source] Gamma radiation sensitivity of the eggs, larvae and pupae of Indian meal moth Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 5 2008Abdurrahman Ayvaz Abstract BACKGROUND: This study focused on determining the minimal effective gamma radiation dose that prevents commodity damage caused by the Indian meal moth Plodia interpunctella (Hübner). The study was also designed to assess the effect of releasing either partially sterilized males alone or both partially sterilized males and females on the reproductive potential of P. interpunctella populations. RESULTS: The dose of radiation required to prevent larval emergence from irradiated eggs was 350 Gy, and the same dose was also required to prevent adult emergence from mature larvae. A dose of 300 Gy was not able to prevent adult emergence from irradiated pupae. The dose at which 100% sterility was achieved in treated females mated to treated males was 300 Gy for the parental generation of irradiated pupae. Fertility of the parental males from irradiated pupae was 48.17% at 300 Gy in treated males crossed with untreated females, but male progeny of irradiated male parents had a residual fertility of 11.06% at the same dose. CONCLUSION: F1 males from irradiated pupae were more sterile than parental males. To prevent larval emergence from irradiated eggs, a dose of 350 Gy is required. The same dose is required to prevent the larvae from reaching the adult stage. Copyright © 2008 Society of Chemical Industry [source] Genetic life history effects on juvenile survival in bluegillJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2007B. D. NEFF Abstract Foraging behaviour under the risk of predation has important consequences on an individual's survivorship and fitness. In bluegill (Lepomis macrochirus), we have recently shown that offspring sired by males of alternative life histories differ in their foraging behaviour. Specifically, offspring sired by ,cuckolder' males take fewer risks during foraging than do offspring sired by ,parental' males. This behavioural difference can have important consequences on the fitness of the two life histories and thus the underlying evolutionary mechanism. Here, we examine the consequences of this behavioural variation on growth rate, condition and survivorship during early development of juveniles. We used split in vitro fertilization to generate maternal half-sibs that differed in sire life history. The resulting 18 455 larvae from 50 families were released into a microcosm with safe and risky foraging areas for approximately 2 months. A total of 262 juveniles (1.4%) survived of which parentage was unambiguously determined using microsatellite genetic markers for 254 (97%). Although we found significant dam effects, there was no difference in apparent growth rate or condition of juveniles sired by males of the two life histories. Of the 25 paired half-sib families, 15 had higher survivorship when sired by a cuckolder male, seven had higher survivorship when sired by a parental male and three had no surviving offspring from either sire. Thus, although growth was similar between the two offspring types, survivorship was not. Combining the differential survivorship estimate with paternity data from natural nests and the frequency of males adopting each life history, we calculated that the cuckolder life history has 1.87 times higher fitness than the parental life history. As such, the life histories likely are not governed by a genetic polymorphism. [source] |