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131.
Effects of Growth Hormone on In Situ Culture of Bovine Preantral Follicles are Dose Dependent
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CR Jimenez JL de Azevedo RG Silveira J Penitente‐Filho EL Carrascal‐Triana AM Zolini VR Araújo CAA Torres 《Reproduction in domestic animals》2016,51(4):575-584
The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ. 相似文献
132.
Anthony R Palmer Igshaan Samuels Clement Cupido Andiswa Finca W Fransiska Kangombe Isa AM Yunusa 《African Journal of Range and Forage Science》2016,33(1):43-51
Following a field campaign to determine the species composition, canopy cover, aboveground annual production and leaf area index (LAI) of the semi-arid savanna of north-western Namibia, we present a production model that can be used by graziers to determine the livestock carrying capacity. The model predicts the annual aboveground net primary production (ANPP) from regression equations of canopy cover by annual production fraction for plant functional classes. We tested the output of the model against another fully independent net primary production (NPP) model, namely the MODIS NPP product. The mean MODIS NPP for the 29 sites was 343 ± 22?kg dry matter (DM) ha?1 y?1 as opposed to 285 ± 142?kg DM ha?1 y?1 for the fAP model that used the regression method (p < 0.01). As a proof of concept, these landscape-scale ANPP values are used to calculate a recommended livestock carrying capacity for the Ehirovipuka Communal Conservancy, a 1 980 km2 communal area with both wildlife and livestock populations. In addition, we also provide details of a field method for predicting landscape-scale LAI from line transect data. This approach can be used to ground reference the LAI values generated from the MODIS LAI product. 相似文献
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Paediatrician and Caregiver Awareness of Cryptosporidiosis and Giardiasis in Children: US Survey Responses
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F. M. Munoz E. Attias S. J. Czinn J. Black the Persistent Diarrhea Working Group 《Zoonoses and public health》2016,63(5):410-419
There appears to be no published information concerning the awareness and knowledge about diarrhoea caused by Cryptosporidium spp. or Giardia lamblia among US paediatricians and caregivers of young children. Two concurrent, separate surveys were conducted among paediatricians and caregivers (~1000 respondents in each survey) of children ages 1–12 years concerning their knowledge, perceptions and attitudes in the diagnosis and treatment of parasitic diarrhoea. Awareness of parasite‐induced diarrhoea was low for specific aspects among both paediatricians and caregivers. Educational efforts to improve awareness on the appropriate clinical presentation, management and treatment of cryptosporidiosis and giardiasis in children with persistent diarrhoea should be undertaken. 相似文献
136.
The investigation of five field cases of chronic copper poisoning in a group of 100 Angora kids is reported. Toxicity was confirmed by the demonstration of Heinz body anaemias, necrotizing liver disease, haemoglobinuric nephrosis and excessive levels of copper in blood, livers and kidneys. The dietary history of the kids is described. Tissue levels of copper and reported interactions between selenium, zinc and copper are discussed. Therapeutic and preventative measures are suggested. 相似文献
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Obtaining Wisent early blastocyst in vitro is a basic for protection and creation of biodiversity for this threatened species
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AM Duszewska P Gręda M Baraniewicz W Bielecki W Niżański A Partyka M Tracz Z Nowak A Chełmońska‐Soyta W Olech 《Reproduction in domestic animals》2018,53(3):818-821
Wisent, or European bison (Bison bonasus), is listed as “vulnerable” on the IUCN Red List of Threatened Species and is therefore protected by international law. For the first time, a Wisent embryo has been obtained in vitro. This procedure creates a new opportunity to protect and increase Wisent reproductive potential and thereby opens new possibilities for the establishment of a controlled and broad reserve of the gene pool. 相似文献
139.
Evidence of increased Hepatitis E virus exposure in Lao villagers with contact to ruminants
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Silvia E. Tritz Vilaysone Khounvisith Sisavath Pommasichan Khampasong Ninnasopha Amphone Keosengthong Vannaphone Phoutana Margot Camoin Judith M. Hübschen Antony P. Black Claude P. Muller Chantal J. Snoeck Maude Pauly 《Zoonoses and public health》2018,65(6):690-701
Although pigs are the main reservoir, ruminants have also been shown to be susceptible to hepatitis E virus (HEV). We investigated zoonotic transmission of HEV in rural settings of Lao People's Democratic Republic (Lao PDR) where humans are in close contacts with ruminants and where pigs are rare. Villagers with (n = 171, risk group) and without (n = 155, control group) cattle were recruited in seven villages in Vientiane Capital. Owners of pigs were excluded. Blood, as well as information on socio‐demographics, animal contact, dietary habits and awareness of zoonoses were collected to assess risk factors. Blood and rectal swabs were collected from cattle (n = 173) and other ruminants (27 goat, 5 buffaloes) to measure anti‐HEV antibody and virus prevalence. A similar anti‐HEV antibody seroprevalence was found in cattle (6.8%) and other ruminants (8%). HEV RNA was detected in none of the animal rectal swabs and human sera. Anti‐HEV IgG seroprevalence was higher in cattle farmers than in the control group (59.1% vs. 43.9%, p = 0.008) and increased significantly with age. Other risk factors included male gender, close contact with cattle and consumption of undercooked meat. We find that HEV is highly endemic in rural Laos and provide first evidence that HEV circulates in free‐roaming ruminants with open access to village water sources. Despite some awareness about hygiene, villagers are likely constantly exposed to zoonotic diseases by dietary and lifestyle habits. Cattle farmers had a higher risk of HEV infection than other villagers. Our study highlights the need to raise the awareness of the rural population about water‐ and food‐borne pathogens, and about the role of cattle as a possible source of infection. The knowledge gained on local risk factors and husbandry conditions should guide future awareness raising campaigns and promote appropriate hygienic measures including handwashing and the consumption of safe food and water. 相似文献
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