Chromosome structural change has long been considered important in the evolution of post-zygotic reproductive isolation. The premise that karyotypic variation can serve as a possible barrier to gene flow is founded on the expectation that heterozygotes for structurally distinct chromosomal forms would be partially sterile (negatively heterotic) or show reduced recombination. We report the outcome of a detailed comparative molecular cytogenetic study of three antelope species, genus Raphicerus, that have undergone a rapid radiation. The species are largely conserved with respect to their euchromatic regions but the X chromosomes, in marked contrast, show distinct patterns of heterochromatic amplification and localization of repeats that have occurred independently in each lineage. We argue a novel hypothesis that postulates that the expansion of heterochromatic blocks in the homogametic sex can, with certain conditions, contribute to post-zygotic isolation. i.e., female hybrid incompatibility, the converse of Haldane's rule. This is based on the expectation that hybrids incur a selective disadvantage due to impaired meiosis resulting from the meiotic checkpoint network's surveillance of the asymmetric expansions of heterochromatic blocks in the homogametic sex. Asynapsis of these heterochromatic regions would result in meiotic silencing of unsynapsed chromatin and, if this persists, germline apoptosis and female infertility.

• MeSH
• antilopy klasifikace   genetika   MeSH
• chromozom X ultrastruktura   MeSH
• heterozygot MeSH
• hybridizace genetická MeSH
• hybridizace in situ fluorescenční MeSH
• karyotyp * MeSH
• meióza MeSH
• modely genetické * MeSH
• rekombinace genetická MeSH
• reprodukční izolace * MeSH
• sexuální faktory MeSH
• tok genů MeSH
• vznik druhů (genetika) * MeSH
• ženská infertilita genetika   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Afrika MeSH

Although rabies incidence has fallen sharply over the past decades in Europe, the disease is still present in Eastern Europe. Oral rabies immunization of wild animal rabies has been shown to be the most effective method for the control and elimination of rabies. All rabies vaccines used in Europe are modified live virus vaccines based on the Street Alabama Dufferin (SAD) strain isolated from a naturally-infected dog in 1935. Because of the potential safety risk of a live virus which could revert to virulence, the genetic composition of three commercial attenuated live rabies vaccines was investigated in two independent laboratories using next genome sequencing. This study is the first one reporting on the diversity of variants in oral rabies vaccines as well as the presence of a mix of at least two different variants in all tested batches. The results demonstrate the need for vaccine producers to use new robust methodologies in the context of their routine vaccine quality controls prior to market release.

• MeSH
• atenuované vakcíny * MeSH
• divoká zvířata * MeSH
• genetická variace MeSH
• genom virový MeSH
• nemoci zvířat prevence a kontrola   MeSH
• rabies veterinární   MeSH
• RNA virová MeSH
• vakcína proti vzteklině genetika   imunologie   MeSH
• vakcinace veterinární   MeSH
• virus rabies genetika   imunologie   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• atenuované vakcíny * MeSH
• RNA virová MeSH
• vakcína proti vzteklině MeSH

Mycobacterium avium subsp. paratuberculosis (MAP) has a high degree of resistance to chemical and physical procedures frequently used for the elimination of other bacteria. Recently, a method for the determination of viability by exposure of MAP to propidium monoazide (PMA) and subsequent real time quantitative PCR (qPCR) was established and found to be comparable with culture. The aim of this study was to apply the PMA qPCR method to determine the impact of increasing concentration or time and repeated cycles of the application of selected disinfectants on MAP viability. Different MAP isolates responded to the same type of stress in different ways. The laboratory strain CAPM 6381 had the highest tolerance, while the 8819 low-passage field isolate was the most sensitive. Ultraviolet exposure caused only a partial reduction in MAP viability; all MAP isolates were relatively resistant to chlorine. Only the application of peracetic acid led to the total elimination of MAP. Repeated application of the treatments resulted in more significant decreases in MAP viability compared to single increases in the concentration or time of exposure to the disinfectant.

• Klíčová slova
• Disinfection, Mycobacterium avium subsp. paratuberculosis, Propidium monoazide quantitative PCR, Viability,
• MeSH
• azidy * MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• chlor farmakologie   MeSH
• dezinficiencia farmakologie   MeSH
• kvantitativní polymerázová řetězová reakce veterinární   MeSH
• kyselina peroctová farmakologie   MeSH
• mikrobiální viabilita účinky léků   MeSH
• Mycobacterium avium subsp. paratuberculosis účinky léků   MeSH
• propidium analogy a deriváty   MeSH
• ultrafialové záření MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• azidy * MeSH
• bakteriální proteiny MeSH
• chlor MeSH
• dezinficiencia MeSH
• kyselina peroctová MeSH
• propidium monoazide MeSH Prohlížeč
• propidium MeSH

The significance of maternal immunity against non-typhoid Salmonella spp. acquired by piglets via colostrum and milk was evaluated in a Salmonella enterica serovar Typhimurium challenge experiment. Piglets from sows vaccinated with an experimental inactivated vaccine exhibited high levels of serum immunoglobulins G and A against S. Typhimurium 4 days after birth, just prior to experimental oral challenge. The S. Typhimurium load in the ileal and caecal wall of piglets 3 days after experimental inoculation was lower by a 2-log magnitude compared to unvaccinated controls. Such a vaccine, delivering colostral/lactogenic immunity to piglets thus has the potential to reduce the prevalence non-typhoid Salmonella spp. infection.

• MeSH
• bakteriální nálož veterinární   MeSH
• bakteriální vakcíny imunologie   MeSH
• cékum mikrobiologie   MeSH
• ileum mikrobiologie   MeSH
• imunita získaná od matky * MeSH
• imunoglobulin A krev   MeSH
• imunoglobulin G krev   MeSH
• inaktivované vakcíny imunologie   MeSH
• kolostrum imunologie   MeSH
• mléko imunologie   MeSH
• nemoci prasat imunologie   mikrobiologie   MeSH
• novorozená zvířata MeSH
• prasata MeSH
• Salmonella typhimurium imunologie   MeSH
• salmonelová infekce u zvířat imunologie   mikrobiologie   MeSH
• slizniční imunita MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální vakcíny MeSH
• imunoglobulin A MeSH
• imunoglobulin G MeSH
• inaktivované vakcíny MeSH

Shiga-toxigenic E. coli (STEC) strains that produce Shiga toxin Stx2e cause oedema disease in weaned piglets. The purpose of the present study was to investigate the impact of Stx2e released in mesenteric lymph nodes on disease pathogenesis. Colistin and ampicillin were intramuscularly administered to piglets of the experimental group simultaneously challenged with STEC strain, type O139:F18ab, Stx2e+. Piglets of the control group were challenged with STEC only. The strain was naturally resistant to ampicillin and susceptible to colistin. After the challenge, colonisation of the intestines was observed in both antibiotic-treated piglets and control piglets without antibiotic treatment. Histochemistry and scanning electron microscopy revealed sporadic colonisation of the small intestine in the piglets. STEC was detected in the mesenteric lymph nodes of untreated piglets. The clinical manifestations of oedema disease were observed in both groups. In the antibiotic-treated group (11 piglets), oedema disease developed in 10 piglets, eight of which died or were euthanized ante finem. In the untreated group (11 piglets), oedema disease developed in five piglets, four of which died or were euthanized ante finem. We therefore propose that the STEC lysed by colistin suddenly released the toxin from bacterial cells immediately after their passage through the intestinal wall. That could explain a more severe course of oedema disease in the treated piglets. Even though high amounts of STEC were present in the lymph nodes of untreated piglets, the toxin was not released abruptly because the bacterial cells were not damaged.

• MeSH
• ampicilin aplikace a dávkování   farmakologie   MeSH
• antibakteriální látky aplikace a dávkování   farmakologie   MeSH
• časové faktory MeSH
• edémová nemoc u prasat farmakoterapie   mikrobiologie   mortalita   MeSH
• feces mikrobiologie   MeSH
• infekce vyvolané Escherichia coli farmakoterapie   mikrobiologie   mortalita   veterinární   MeSH
• injekce intramuskulární veterinární   MeSH
• kolistin aplikace a dávkování   farmakologie   MeSH
• lymfatické uzliny mikrobiologie   MeSH
• odstavení MeSH
• prasata MeSH
• rezistence na ampicilin MeSH
• shiga-toxigenní Escherichia coli účinky léků   růst a vývoj   patogenita   MeSH
• střeva mikrobiologie   MeSH
• studie případů a kontrol MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• ampicilin MeSH
• antibakteriální látky MeSH
• kolistin MeSH

From July to September 2005, 1075 wild birds of 37 species were mist-netted at a location in the north-eastern part of the Czech Republic. The birds were examined for the presence of avipoxvirus lesions. This was demonstrated by electron microscopy in skin lesions in nine of 244 blackcaps (Sylvia atricapilla) examined (4% prevalence). Blackcaps skin bioptates were processed using the ultrathin section method. In skin bioptates, avipoxviruses were demonstrated in intracytoplasmic inclusions where, in addition to mature viruses, lipids and filamentous structures concentrated into large circular formations were found. The so-called additional inclusions were also found. These did not contain any virus components, and they served as the precursor of A-type intracytoplasmic inclusions. Blackcap avipoxvirus was isolated by passage on the chorioallantoic membrane of 9-day-old chicken embryos. The virus was successfully adapted after 11 passages (each passage lasted 5 to 7 days), at which time a marked changes in the form of tiny nodules 2 to 3 mm in diameter were observed on the chorioallantoic membrane. Further identification of field isolates and of the cultured virus was carried out using polymerase chain reaction and sequencing. Sequences were compared with consensus sequences of both canarypoxviruses and fowlpoxviruses. Our sequence was found to be 98.8% identical to the canarypox consensus sequence, but only 63% identical to the fowlpox consensus sequence. Our avipoxvirus sequence was proven to be significantly more closely related to canarypoxviruses than to fowlpoxviruses also by phylogenetic analysis.

• MeSH
• Avipoxvirus izolace a purifikace   ultrastruktura   MeSH
• chorioalantoická membrána patologie   virologie   MeSH
• infekce vyvolané poxviry epidemiologie   veterinární   virologie   MeSH
• kuřecí embryo MeSH
• nemoci ptáků epidemiologie   virologie   MeSH
• Passeriformes virologie   MeSH
• prevalence MeSH
• zvířata MeSH
• Check Tag
• kuřecí embryo MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH