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We studied the effect of maternal stress evoked by a severe stressor from the cues of predation risk during gestation on the growth of offspring in root volesMicrotus oeconomus Pallas, 1776. Body mass of both male and female offspring was significantly reduced in the period from birth to weaning. Females showed compensatory growth after weaning, whereas males maintained low body mass at weaning into adulthood. Maternal stress led to an elevated plasma corticosterone level in male offspring, but did not affect that of female offspring. Corticosterone levels remained elevated in males from stressed dams into adulthood. Increased levels of plasma corticosterone may have led to the inhibition of pituitary growth hormone and a chronically abnormal energy mobilization, considering the greater energy and metabolic requirements of male offspring, this may account for the sex-specific differences in compensatory growth. We suggest that in the high stress situation, endocrine-based sex-biased effects of maternal stress as a primary factor can lead to long-term physical and ecological consequences for male offspring.
The effect of L-carnitine supplementation during gestation and lactation on the performance parameters of sows was studied. The trial comprised a total of 73 sows that were divided into the control and treated groups; each was fed diets with and without supplemental L-carnitine during pregnancy (0 vs. 125 mg L-carnitine daily/sow) and lactation (0 vs. 250 mg L-carnitine daily/sow). L-carnitine supplementation resulted in the numerical increase of sow body weight at weaning (215.2±5.4 vs. 205.0±5.0, LSM±Se, p≥0.05), with a significantly expressed effect on sows born in 1998 (227.1±8.4 vs. 193.6±9.2, LSM±Se, p=0.01). There was a numerical increase in average number of total born and viable piglets per litter in treated sows (11.0±2.0 vs. 10.7±1.9, LSM±Se, p≥0.05; 10.8±2.1 vs. 10.4±1.9, LSM±Se, p≥0.05 respectively), although the tendency towards increasing the same parameters was determined in sows born in 1998 (11.00±0.54 vs. 9.82±0.59, LSM±Se, p=0.14; 10.9±0.6 vs. 9.5±0.6, LSM±Se, p=0.09). The total number of piglets which were smaller than 800g at birth tended to be lower (0.9±1.2 vs. 1.4±1.6, LSM±Se, p=0.08) and significantly different in sows born in 1998 (0.9±0.4 vs. 2.5±0.4, LSM±Se, p=0.01). The number of piglets fit for rearing was influenced by L-carnitine supplementation only in the sows born in 1998 (10.8±0.5 vs. 9.1±0.6, LSM±Se, p=0.03). The litter weight was not influenced by L-carnitine supplementation.
Home range size and activity pattern were evaluated by radiotracking for seven red fox Vulpes vulpes (Linnaeus, 1758) breeding females, in the Doñana Biological Reserve, SW Spain. Mean home range size was 218 ha (SD = 76, n = 7). A home range for one of the seven females was 1129 ha for one nearly complete year and only 253 ha for the same female during the breeding season. We suggest that this size reduction could be a result of energetical and behavioral shifts due to the breeding condition. Activity was slightly increased during nights with long resting periods during light hours. Total mean travelling distances was 6686 m in 24-hour cycles. Daytime and nighttime mean distance covered were 2101 and 4585 m, respectively.
Isopropylantipyrine (IPA, propyphenazone) is a pyrazolone derivative, widely used as an antipyretic and analgesic drug. The aim of the study was to evaluate the influence of propyphenazone on rat development. IPA was administered to pregnant rats from day 8 to day 14 of pregnancy once a day, orally by a stomach tube at doses of 2.10 (R1), 21.0 (R2), and 210.0 mg/kg/day (R3). The dams were sacrificed on day 21 of gestation and corpora luteum, implants, resorptions, and live foetuses were counted. The weight of foetuses and placentas, the length of foetuses and their tails were checked. The foetuses were fixed in alcohol and skeletons were stained with alizarin. There was a statistical difference in body length in R1, R2 and numbers of subcutaneous ecchymose in R1. External and skeletal examination of the foetuses revealed no evidence of teratogenesis. It can be concluded that IPA has no harmful effects on the prenatal development of the rat offspring at doses used in the present study.
Neospora caninum is transmitted from a cow to its foetus by vertical transmission and the timing of infection in gestation is an important factor in determining the disease outcome. Few studies have explored the role of the placenta in the outcome of N. caninum infection during pregnancy. Here, we described the N. caninum presence, parasite load, local immune response, and histopathological lesions at the materno-foetal interface after infection of BALB/c mice at early and late stages of gestation. In mice infected at early gestation, N. caninum DNA was detected in foetoplacentary units 7 days post-infection (PI) and in the placenta, but not in viable foetuses on day 14 PI, indicating that the parasite was multiplying primarily in the placental tissues without reaching the foetus. Moreover, parasite DNA was detected in resorptions, suggesting that foetal death could be a consequence of infection. An increase in IFN-γ, TNF-α and IL-10 expression was observed in N. caninum PCR-positive placentas, which could favour N. caninum foetal transmission and be harmful to both the placenta and the foetus. Histopathological analysis revealed necrosis affecting both the maternal and foetal sides of the placenta. At late gestation, transmission occurred rapidly following infection (day 3 PI), but parasite were rarely found. In addition, an increase in cytokine expression was observed in spleen and placental tissues from infected animals, while a downregulation in IL-4 expression was only observed in the spleen. Finally, necrosis in the placenta was limited to the maternal side, suggesting that the parasite is mainly multiplying in the placental tissue at this stage. Thus, the results of the present study indicate that the placenta may be actively involved in N. caninum pathogenesis.
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