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981.

Background

Bovine brucellosis remains one of the most prevalent zoonotic infections affecting dairy cattle in developing countries where the applied control programs often fail. We analyzed the epidemiologic pattern of bovine brucellosis in a dairy cattle herd that showed several cases of abortions after regular vaccination with RB51 (B. abortus vaccine). In 2013 thirty dairy cows, from a Holstein-Friesian dairy herd with a population of 600 cattle, aborted five months post vaccination by a regular RB51 vaccine. Blood samples were drawn from milking cows and growing heifers, as well as heifers and cows pregnant up to 6 months. These samples were collected in June 2013 (n?=?257) and May 2014 (n?=?263) and were tested by real time (rt)-PCR as well as serological tests, in particular Rose Bengal Test (RBT), Enzyme-Linked Immunosorbent Assays (ELISA) and Fluorescence Polarization Assay. Tissue specimens were also collected from an aborted fetus and cultured. Isolates were subjected to bacteriological typing tests at the genus and species levels.

Results

Five months post vaccination with RB51 vaccine, Brucella (B.) DNA was detected in blood samples of cows by rt-PCR. The serological tests also revealed the spread of Brucella field strains within the herd in 2013. Four Brucella isolates were recovered from specimens collected from the aborted fetus. These isolates were typed as follows: one B. abortus RB51 vaccine strain and three isolates of B. abortus field strain. The seropositive cows with positive rt-PCR might indicate an infection by the Brucella field strain; while the positive rt-PCR results from seronegative animals may either be due to circulating RB51 vaccine DNA in vaccinated animals or to circulating field strain in infected animals before seroconversion.

Conclusion

The results herein suggest that PCR can be a good supplementary tool in an outbreak situation, if an assay is available that can differentiate vaccine and field strains with a high analytical sensitivity. We recommend using RBT and ELISA in parallel in outbreak situations, to identify as many infected animals as possible during the initial screenings. This test procedure should be repeated for at least three successive negative tests, with one month interval.
  相似文献   
982.
An unusual case of an 11-month-old, black Limousin-cross heifer, with an 8-month history of episodic seizures and photosensitisation, was referred by a veterinary practitioner to the Farm Animal Section of the UCD Veterinary Hospital, School of Veterinary Medicine, University College Dublin, Ireland, in August 2014. Following an investigation, a diagnosis of Bovine Congenital Erythropoietic Protoporphyria (BCEPP) was made. To the authors’ knowledge this is the first report of such a case in Ireland. BCEPP should be considered as a differential diagnosis in young animals displaying periodic seizures and/or photosensitisation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13620-015-0044-3) contains supplementary material, which is available to authorized users.  相似文献   
983.
Canine melanoma is one of the most important diseases in small animal medicine. Protein phosphatase 2A (PP2A), a well conserved serine/threonine phosphatase, plays a critical role as a tumor suppressor. SET/I2PP2A is an endogenous inhibitor for PP2A, which directly binds to PP2A and suppresses its phosphatase activity. Elevated SET protein levels have been reported to exacerbate human tumor progression. The role of SET in canine melanoma, however, has not been understood. Here, we investigated the potential therapeutic role for SET inhibitors in canine melanoma. The expression of SET protein was observed in 6 canine melanoma cell lines. We used CMeC-1 cells (primary origin) and CMeC-2 cells (metastatic origin) to generate cell lines stably expressing SET-targeting shRNAs. Knockdown of SET expression in CMeC-2, but not in CMeC-1, leads to decreased cell proliferation, invasion and colony formation. Phosphorylation level of p70 S6 kinase was decreased by SET knockdown in CMeC-2, suggesting the involvement of mTOR (mammalian target of rapamycin)/p70 S6 kinase signaling. The SET inhibitors, OP449 and FTY720, more effectively killed CMeC-2 than CMeC-1. We observed PP2A activation in CMeC-2 treated with OP449 and FTY720. These results demonstrated the potential therapeutic application of SET inhibitors for canine melanoma.  相似文献   
984.
This report describes a dog that developed erythema multiforme in temporal association with administration of the sulphonamide‐based anticonvulsant drug zonisamide. Similar adverse drug reactions have been associated with sulphonamide antimicrobial drugs. Caution should be exercised when prescribing this medication for dogs with known hypersensitivity to sulphonamides.  相似文献   
985.
986.
Epigenetics provides a molecular mechanism of inheritance that is not solely dependent on DNA sequence and that can account for non-Mendelian inheritance patterns. Epigenetic changes underlie many normal developmental processes, and can lead to disease development as wel. While epigenetic effects have been studied in wel-characterized rodent models, less research has been done using agricultural y important domestic animal species. This review wil present the results of current epigenetic research using farm animal models(cattle, pigs, sheep and chickens). Much of the work has focused on the epigenetic effects that environmental exposures to toxicants, nutrients and infectious agents has on either the exposed animals themselves or on their direct offspring. Only one porcine study examined epigenetic transgenerational effects; namely the effect diet micronutrients fed to male pigs has on liver DNA methylation and muscle mass in grand-offspring(F2 generation). Healthy viable offspring are very important in the farm and husbandry industry and epigenetic differences can be associated with production traits. Therefore further epigenetic research into domestic animal health and how exposure to toxicants or nutritional changes affects future generations is imperative.  相似文献   
987.
Adelgids (Hemiptera) in the genus Pineus have been reported as introduced insect pests causing serious losses to Pinus plantations worldwide. In 2008, Pineus boerneri was recorded for the first time in Colombia, with infestations noted on Pinus kesiya, P. tecunumanii, P. maximinoi and P. oocarpa. The lack of information on this insect in Colombia prompted investigations of its life cycle and infestation levels as well as host susceptibility of the main Pinus species planted in Colombia. In addition, the possibility of using a Ceraeochrysa species, an already established predator of adelgids in Colombia, for biological control was considered. Results showed that Pineus boerneri in Colombia has an anholocyclic life cycle comprised of four instars with a complete duration of between 49 and 97 d. Infestations were higher in the middle and upper part of trees. Pinus kesiya and P. maximinoi had the highest levels of susceptibility in field as well as in greenhouse trials. A survey of naturally infested trees showed P. tecunumanii to be moderately susceptible, whereas P. patula and P. oocarpa had low levels of susceptibility in a greenhouse trial but were not susceptible in the field. Investigations considering the impact of predation of Ceraeochrysa species showed a high predation rate of up to 140 P. boerneri consumed per day by a single Ceraeochrysa individual. Other predators of P. boerneri were recorded but were not sufficiently common to warrant detailed study.  相似文献   
988.
989.
The antiatherogenic properties of a novel dietary formula (PS-CO) of plant sterol esters of fatty acids, produced by enzymatic interesterification of plant sterols with canola oil (CO), in a CO matrix containing 1,3-diacylglycerol, were evaluated in apolipoprotein E-deficient mice. PS-CO consumption strongly tended to lower total plasma cholesterol levels by 21%, compared to the placebo group. Blood triglycerides were reduced by 38% and 36% compared to CO and placebo-fed mice, respectively. Serum lipid peroxide levels were lowered following PS-CO administration by 62% and 63%, compared to CO and placebo administration, respectively. Unlike CO supplementation, PS-CO consumption preserved serum paraoxonase (PON1) activity. Mouse peritoneal macrophages from PS-CO-fed mice exhibited reduced cellular uptake of oxidized-LDL compared to those from placebo-fed mice and demonstrated a tendency toward a decreased capability to release superoxide anions. These findings indicate that PS-CO supplementation is beneficial in reducing serum lipid levels, and serum and macrophage oxidative stress, thus contributing to the reduction in atherogenic risk factors.  相似文献   
990.
Green tea, tara tannin, and tannic acid have been profiled for their contents of galloylquinic acids using LC-MS8. These procedures have provided evidence for the first observation of (i) 1-galloylquinic acid (11), 1,3,5-trigalloylquinic acid (22), 4-(digalloyl)quinic acid (28), 5-(digalloyl)quinic acid (29), and either 3-galloyl-5-(digalloyl)quinic acid (32) or 3-(digalloyl)-5-galloylquinic acid (33) from any source; (ii) 4-galloyl-5-(digalloyl)quinic acid (34), 5-galloyl-4-(digalloyl)quinic acid (35), 3-(digalloyl)-4,5-digalloylquinic acid (41), 4-(digalloyl)-3,5-digalloylquinic acid (40), 5-(digalloyl)-3,4-digalloylquinic acid (39), and 1,3,4-trigalloylquinic acid (21) from tara tannin; and (iii) 3-galloylquinic acid (12) and 4-galloylquinic acid (14) from green tea. The first mass spectrometric fragmentation data are reported for galloylquinic acids containing between five and eight gallic acid residues. For each of these mass ranges at least two isomers based on the 1,3,4,5-tetragalloylquinic acid core (25) and at least three based on the 3,4,5-trigalloylquinic acid core (24) were observed. Methanolysis of tara tannin yielded methyl gallate, methyl digallate, and methyl trigallate, demonstrating that some of these galloylquinic acids contained at least one side chain of up to four galloyl residues.  相似文献   
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