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81.
Colour‐Doppler ultrasound imaging as a laparoscopy substitute to count corpora lutea in superovulated sheep
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PHN Pinto GM Bragança MFA Balaro EKN Arashiro GB dos Santos GN de Souza JMG Souza‐Fabjan JF Da Fonseca FZ Brandão 《Reproduction in domestic animals》2018,53(1):266-269
This study evaluated colour‐Doppler ultrasound imaging (UI) as a substitute for laparoscopy to count the corpora lutea (CL) in superovulated sheep. Twenty‐five Santa Ines ewes were superovulated three times at 21‐day intervals. Corpora lutea were counted by colour‐Doppler UI (CLDOPPLER) 6 days after each superovulation and confirmed by laparoscopy (CLLAP) 12 hr later. The mean number of CL was similar for both techniques (2.1 ± 2.5 vs. 2.1 ± 2.7 for CLDOPPLER and CLLAP, respectively) with a significant positive correlation (r = .94; r2=.89). Colour‐Doppler UI effectively evaluated the ovarian response in superovulated ewes and efficiently identified animals that did not respond to superovulation. 相似文献
82.
MFA Balaro FZ Brandão ALRS Maia JMG Souza‐Fabjan MI Cueto AE Gibbons JF Fonseca 《Reproduction in domestic animals》2016,51(3):386-391
The aim of the study was to evaluate the feasibility of pre‐selection of high or low responder does prior to the superovulatory protocols. Twenty Saanen does received 800 IU of equine chorionic gonadotropin (eCG) at the end of long‐term progestogen treatment. Fourteen days later, a second progestogen protocol associated with a multiple‐dose follicle stimulation hormone (FSH) treatment (5 IU/kg of FSH, in six decreasing doses between days 4 to 6 of the protocol) was administered. Transrectal ultrasound was used to assess the follicular status at the beginning of superovulatory treatments, at the oestrous onset and on the seventh day of the oestrous cycle for counting corpora lutea (CL). A significant lower number of CL was obtained in eCG‐treated in comparision with FSH‐treated does (p < 0.05). A quartic regression was able to explain the relationship between the number of CL in response to both treatments (r2=0.50; p < 0.05). Seventy per cent (14 of 20) of does maintained the same ovulatory response (high or low) after treatments. The Kappa (κ = 0.40; p < 0.05) and Spearman (rs = 0.39; p = 0.08) coefficients were able to show a relationship between treatments. Regarding the follicular status, there is a significant relationship between the number of small follicles (r = 0.71; r2=0.47; p < 0.01) and total follicles (r = 0.60; p < 0.01) at eCG and first FSH dose with the number of CL. Moreover, it was found a negative relationship between the presence of large follicles and the number of CL in response to eCG treatment (r = ?0.44; p < 0.05), but not from FSH (p > 0.05). In conclusion, the screening test with eCG has the potential to identify Saanen does that will better respond to the superovulatory protocol with FSH. In addition, it highlighted the importance of an ultrasound evaluation prior to the beginning of superovulatory treatments with FSH to characterize the follicular status and identify the potential donors of high ovulatory response in MOET programmes in goats. 相似文献
83.
Thiry E Zicola A Addie D Egberink H Hartmann K Lutz H Poulet H Horzinek MC 《Veterinary microbiology》2007,122(1-2):25-31
The Asian lineage highly pathogenic avian influenza (HPAI) H5N1 virus is a known pathogen of birds. Only recently, the virus has been reported to cause sporadic fatal disease in carnivores, and its zoonotic potential has been dominating the popular media. Attention to felids was drawn by two outbreaks with high mortality in tigers, leopards and other exotic felids in Thailand. Subsequently, domestic cats were found naturally infected and experimentally susceptible to H5N1 virus. A high susceptibility of the dog to H3N8 equine influenza A virus had been reported earlier, and recently also HPAI H5N1 virus has been identified as a canine pathogen. The ferret, hamster and mouse are suitable as experimental animals; importantly, these species are also kept as pets. Experimental intratracheal and oral infection of cats with an HPAI H5N1 virus isolate from a human case resulted in lethal disease; furthermore, cats have been infected by the feeding of infected chickens. Spread of the infection from experimentally infected to in-contact cats has been reported. The epidemiological role of the cat and other pet animal species in transmitting HPAI H5N1 virus to humans needs continuous consideration and attention. 相似文献
84.
J Gonzalez G Passantino A Esnal N Cuesta JA García Vera L Mechelli A Saez JF García Marín M Tempesta 《Reproduction in domestic animals》2017,52(6):1093-1096
An abortion outbreak occurred in a goat herd of Murciano‐Granadina breed in Almeria Region in Spain where 80 pregnant females aborted. All bacteriological and parasitological examinations resulted negative, whereas virological investigations and real‐time PCR assay showed the presence of Caprine alphaherpesvirus 1 DNA in the pathological specimens from aborted foetuses. Nucleotide sequence analysis revealed that the DNA was highly close related to the Swiss strain E‐CH (99.7%) and a little less extent to the Italian BA.1 strain (99.4%). Histopathological examination revealed multifocal, well‐circumscribed, 50‐ to 200‐μm‐diameter foci of coagulative necrosis in the liver, lungs and kidneys of three foetuses. In the periphery of the necrosis, there were frequently epithelial cells with the chromatin emarginated by large, round, amphophilic intranuclear viral inclusion bodies. The source of the infection in the herd could not clearly find out even some hypothesis were formulated. This seems to be the first report of an abortion outbreak due to Caprine alphaherpesvirus 1 in a goat herd in Spain. 相似文献
85.
86.
Adam Burriss Andrew JF Edmunds Daniel Emery Roger G Hall Olivier Jacob Jürgen Schaetzer 《Pest management science》2018,74(6):1228-1238
The pyridine ring, substituted by a trifluoromethyl substituent has been successfully incorporated into molecules with useful biological properties. During the period 1990 to September 2017, 14 crop protection products bearing a trifluoromethyl pyridine have been commercialized or proposed for an ISO common name, covering fungicides, herbicides, insecticides and nematicides. Chemical processes have been developed to provide trifluoromethyl pyridine intermediates, from non‐fluorinated pyridine starting materials, at scale and with affordable costs of goods. These attractive starting materials were readily adopted by research chemists, and elaborated through simple chemical modifications into new active ingredients. In a second approach, substituted trifluoromethyl pyridine rings have been constructed from acyclic, trifluoromethyl starting materials, which again has served to identify new active ingredients. Molecular matched pair analysis reveals subtle, yet important differences in physicochemical and agronomic properties of trifluoromethyl pyridines compared with the phenyl analogues. This review focuses on the past 27 years, seeking to identify reasons behind the success of such research programmes, and inspire the search for new crop protection chemicals containing the trifluoromethyl pyridine ring. © 2017 Society of Chemical Industry 相似文献
87.
To obviate the destructive interaction of highly reactive metallocene catalysts with classical silica-based supports while retaining the advantage of supported catalysts, a noninteracting polystyrene support was developed. Supported catalysts for the polymerization of alpha-olefins are prepared by treating lightly cross-linked, chloromethylated polystyrene beads consecutively with a secondary amine, an ammonium salt of a weakly coordinating anion, and a neutral dialkylmetallocene. Catalytic sites are distributed homogeneously throughout the support particle, and the polymerization occurs within the bead, in contrast to traditional surface-supported metallocene catalysts. The copolymerization of ethylene and 1-hexene at 40 degreesC affords discrete spherical polyolefin beads with a size (0.3 to 1.4 millimeters) that varies according to the polymerization time. 相似文献
88.
ABSTRACTConsumers perceive pasture-based systems of milk production as natural and therefore better for cow welfare than confinement systems. However both systems are heterogeneous and continually evolving, varying from total confinement to total pasture with many hybrid intermediaries. To compare the welfare of dairy cows in these various systems, we use the three spheres framework, comprising biological functioning, natural behaviour and affective states. Considering biological functioning, pasture-based cows are less at risk of subclinical and clinical mastitis, claw lesions, lameness, metritis, early embryonic mortality, culling and mortality, but at more risk of internal parasitism, malnutrition and delayed onset of oestrous activity postpartum than confined cows. Regarding natural behaviours, pasture-based cows exhibit less agonistic behaviour, better lying behaviour, more normal oestrous behaviours and better synchronicity of behaviours than confined cows. They also have the opportunity to graze, which is one of the main features of the behavioural repertoire of dairy cows, but, they may also experience long periods away from pasture in larger herds, and severe climatic stresses which will become increasingly important as the climate changes. Our current ability to assess the affective state of dairy cows is poor. For example, hunger is an important subjective state that cannot be measured directly. The growing focus on ensuring that animals have lives worth living, means that dairy cows should garner some positive emotions from their lives, and it seems clear that pasture access is essential for this. Clearly measurement of affective state is an important challenge for future dairy cow welfare research. At the extremes of management systems, there can be major differences in animal welfare but in hybrid systems, dairy cows experience elements of both confinement and pasture which may ameliorate the negative effects of each on cow welfare. Ultimately, the optimal system gives cows an element of choice between both environments. Moreover management of the system, whether it is confinement or pastured-based, may be as important as the system of management in ensuring good dairy cow welfare and addressing societal concerns.Abbreviations: BCS: Body condition score; TMR: Total mixed ration 相似文献
89.
Rodolphe E Gozlan Demetra Andreou Takashi Asaeda Kathleen Beyer Rachid Bouhadad Dean Burnard Nuno Caiola Predrag Cakic Vesna Djikanovic Hamid R Esmaeili Istvan Falka Duncan Golicher Akos Harka Galina Jeney Vladimír Kováč Jiří Musil Annamaria Nocita Meta Povz Nicolas Poulet Tomas Virbickas Christian Wolter A Serhan Tarkan Elena Tricarico Teodora Trichkova Hugo Verreycken Andrzej Witkowski Chun Guang Zhang Irene Zweimueller J Robert Britton 《Fish and Fisheries》2010,11(4):315-340
In recent years, policy‐makers have sought the development of appropriate tools to prevent and manage introductions of invasive species. However, these tools are not well suited for introductions of non‐target species that are unknowingly released alongside intentionally‐introduced species. The most compelling example of such invasion is arguably the topmouth gudgeon Pseudorasbora parva, a small cyprinid species originating from East Asia. A combination of sociological, economical and biological factors has fuelled their rapid invasion since the 1960s; 32 countries (from Central Asia to North Africa) have been invaded in less than 50 years. Based on a combination of monitoring surveys (2535 populations sampled) and literature reviews, this paper aims to quantify and characterise important invasion parameters, such as pathways of introduction, time between introduction and detection, lag phase and plasticity of life history traits. Every decade, five new countries have reported P. parva introduction, mainly resulting from the movement of Chinese carps for fish farming. The mean detection period after first introduction was 4 years, a duration insufficient to prevent their pan‐continental invasion. High phenotypic plasticity in fitness related traits such as growth, early maturity, fecundity, reproductive behaviour and the ability to cope with novel pathogens has predisposed P. parva to being a strong invader. The Pseudorasbora parva invasion has provided quantitative data for the development of 1) early warning systems across different spatial scales; 2) rapid eradication programmes prior to natural spread in open systems and 3) sound risk assessments with emphasis on plasticity of life history traits. 相似文献
90.
Distribution of thiobacillus ferrooxidans and leptospirillum ferrooxidans: implications for generation of acid mine drainage 总被引:1,自引:0,他引:1
MO Schrenk KJ Edwards RM Goodman RJ Hamers JF Banfield 《Science (New York, N.Y.)》1998,279(5356):1519-1522
Although Thiobacillus ferrooxidans and Leptospirillum ferrooxidans are widely considered to be the microorganisms that control the rate of generation of acid mine drainage, little is known about their natural distribution and abundance. Fluorescence in situ hybridization studies showed that at Iron Mountain, California, T. ferrooxidans occurs in peripheral slime-based communities (at pH over 1.3 and temperature under 30 degreesC) but not in important subsurface acid-forming environments (pH 0.3 to 0.7, temperature 30 degrees to 50 degreesC). Leptospirillum ferrooxidans is abundant in slimes and as a planktonic organism in environments with lower pH. Thiobacillus ferrooxidans affects the precipitation of ferric iron solids but plays a limited role in acid generation, and neither species controls direct catalysis at low pH at this site. 相似文献