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41.
This study describes the distribution of galanin (Gal) and galanin receptor 2 (GalR2) in the pre‐optic area (POA) of the female guinea pig. Frozen sections were undergone for a routine immunofluorescence labelling. Gal and GalR2 display immunoreactivity in all parts of the pre‐optic area. Gal shows reactivity both in perikarya and fibres, whereas GalR2 was observed only in perikarya. Gal‐ and GalR2‐immunoreactive (‐ir) perikarya were the most numerous in the medial pre‐optic area (MPA) with the highest reactivity in its dorsal part. In the median pre‐optic nucleus (MPN) and periventricular pre‐optic nucleus (PPN), only single Gal‐ and GalR2‐ir neurons were observed. The highest density of Gal‐ir fibres was revealed in the PPN and the lowest in the lateral pre‐optic area (LPA). The results of this study indicate that the distribution pattern of Gal containing neurons overlaps well with the distribution pattern of GalR2‐positive neurons, especially in the MPA. This may suggest GalR2‐dependent activity in this brain region.  相似文献   
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This case study describes the first genetically confirmed and clinically manifested autochthonous Ehrlichia canis infection in a 9‐year‐old female mixed‐breed dog from Romania. Health screening of the dog included clinical examination, evaluation of stained peripheral blood smear and hematologic variables, as well as serologic testing and molecular analysis. Clinical signs included fever, apathy, dehydration, pale mucous membranes, and weakness. The microscopic examination of the blood smear and immunologic assays for Borrelia burgdorferi, Anaplasma phagocytophilum, and E canis antibodies, and for Dirofilaria immitis antigen yielded negative results. Hematologic abnormalities included moderate nonregenerative anemia, leucopenia with neutropenia, and moderate thrombocytopenia. The biochemical abnormalities identified were hypoalbuminemia, and mildly increased serum enzyme activities of AST and ALT. In addition, increased urea and creatinine levels associated with low urine specific gravity and proteinuria were also present. Nested PCR amplification of the partial E canis 16S rRNA gene demonstrated the presence of this rickettsial pathogen in the dog's blood, which subsequently was confirmed through sequencing based on the 100% homology with GenBank deposited E canis isolates. After specific treatment with doxycycline (10 mg/kg, orally, SID) for one month, the proteinuria, and hematologic and serum biochemical abnormalities with the exception of mild azotemia resolved. This report supports the geographical expansion of canine ehrlichiosis caused by E canis in nonendemic regions of Europe.  相似文献   
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We found retardation of preimplantation embryo growth after exposure to maternal restraint stress during the preimplantation period in our previous study. In the present study, we evaluated the impact of preimplantation maternal restraint stress on the distribution of inner cell mass (ICM) and trophectoderm (TE) cells in mouse blastocysts, and its possible effect on physiological development of offspring. We exposed spontaneously ovulating female mice to restraint stress for 30 min three times a day during the preimplantation period, and this treatment caused a significant increase in blood serum corticosterone concentration. Microscopic evaluation of embryos showed that restraint stress significantly decreased cell counts per blastocyst. Comparing the effect of restraint stress on the two blastocyst cell lineages, we found that the reduction in TE cells was more substantial than the reduction in ICM cells, which resulted in an increased ICM/TE ratio in blastocysts isolated from stressed dams compared with controls. Restraint stress reduced the number of implantation sites in uteri, significantly delayed eye opening in delivered mice, and altered their behavior in terms of two parameters (scratching on the base of an open field test apparatus, time spent in central zone) as well. Moreover, prenatally stressed offspring had significantly lower body weights and in 5-week old females delivered from stressed dams, fat deposits were significantly lower. Our results indicate that exposure to stress during very early pregnancy can have a negative impact on embryonic development with consequences reaching into postnatal life.  相似文献   
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The aim of this study was to establish if pre-synchronization would enhance the number of animals cycling prior to conventional breeding at 45 days irrespective of the length of calf separation. Multiparous Bos indicus cows were allotted in four groups (n = 10). Control group (C) dams remained with their calves; groups G24, G48 and G72, which were partially weaned for 24, 48 and 72 h, respectively, were estrus synchronized using a controlled internal drug. These procedures were performed at 25 days and again at 45 days postpartum. The number of follicles, presence of a corpus luteum and back fat thickness (BFT) were determined by ultrasound. The proportion of cows with estrus and ovulation at day 25 postpartum was statistically different between the control and treated groups, with the values being 20, 60, 50 and 70 for the control, G24, G48 and G72 groups respectively (P < 0.05). At days 45 postpartum, the proportion of cows with estrus and ovulation was different in group G48 compared with the other groups (P <0.05). The average BFT and body condition score for the four experimental groups in the two periods were similar (P >0.05). Animals with a higher proportion of follicles from 17 to 21 mm, BFT values above 3.5 mm and a regular body condition were significantly different regardless of whether the dams remained with their calves or were separated, regardless of the length of this event. It can be concluded that (1) a pre-synchronization program at day 25 could trigger the onset of ovarian activity and facilitate a breeding program at day 50 and (2) temporary weaning enhances the effect of a pre-synchronization program.  相似文献   
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As clinical toxoplasmosis is not considered a problem in pigs, the main reason to implement a control strategy against Toxoplasma gondii (T. gondii) in this species is to reduce the establishment of T. gondii tissue cysts in pork, consequently reducing the risk of the parasite entering the human food chain. Consumption of T. gondii tissue cysts from raw or undercooked meat is one of the main sources of human infection, with infected pork being considered a high risk. This study incorporates a mouse bioassay with molecular detection of T. gondii DNA to study the effectiveness of vaccination (incomplete S48 strain) in its ability to reduce tissue cyst burden in pigs, following oocyst (M4 strain) challenge. Results from the mouse bioassay show that 100% of mice which had received porcine tissues from vaccinated and challenged pigs survived compared with 51.1% of mice which received tissues from non-vaccinated and challenged pigs. The presence (or absence) of T. gondii DNA from individual mouse brains also confirmed these results. This indicates a reduction in viable T. gondii tissue cysts within tissues from pigs which have been previously vaccinated with the S48 strain. In addition, the study demonstrated that the main predilection sites for the parasite were found to be brain and highly vascular muscles (such as tongue, diaphragm, heart and masseter) of pigs, while meat cuts used as human food such as chop, loin, left tricep and left semitendinosus, had a lower burden of T. gondii tissue cysts. These promising results highlight the potential of S48 strain tachyzoites for reducing the number of T. gondii tissues cysts in pork and thus improving food safety.  相似文献   
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