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Ameloblastoma is a locally aggressive odontogenic tumour that occurs in humans and dogs. Most ameloblastomas (AM) in humans harbour mutually‐exclusive driving mutations in BRAF, HRAS, KRAS, NRAS or FGFR2 that activate MAPK signalling, and in SMO that activates Hedgehog signalling. The remarkable clinical and histological similarities between canine acanthomatous ameloblastoma (CAA) and AM suggest they may harbour similar driving mutations. In this study, aimed at characterizing the mutational status of SMO, BRAF, HRAS, KRAS, NRAS and FGFR2 in CAA, we used RNA sequencing, Sanger sequencing and restriction fragment length polymorphism assays to demonstrate that 94% of CAA (n = 16) harbour a somatic HRAS p.Q61R mutation. The similarities in MAPK‐activating mutational profiles between CAA and AM implicate conserved molecular mechanisms of tumorigenesis, thus, qualifying the dog as a potentially useful model of disease. Given the relevance of RAS mutations in the pathogenesis of odontogenic tumours and other types of cancer, the results of this study are of comparative, translational, and veterinary value.  相似文献   
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Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h?1·kg?1) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry.  相似文献   
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A biological attack on livestock or poultry could result in the loss of valuable animals, costs related to the containment of outbreaks and the disposal of carcasses, lost trade and other economic effects involving suppliers, transporters, distributors and restaurants; however, it is not possible to secure all livestock, and livestock are much less well guarded than human targets. Thus, the vulnerability of the livestock industry to the introduction of biological agents varies for the following reasons: (i) the majority of lethal and contagious biological agents are environmentally resilient, endemic in foreign countries and harmless to humans, making it easier for terrorists to acquire, handle and deploy these pathogens, (ii) with animals concentrated in fewer production facilities and frequently transported between these facilities, a single pathogen introduction could cause widespread infection and (iii) the extent of human travel around the globe makes it difficult to exclude exotic animal diseases as possible biological agents. Historically, many governments have developed and planned to use biological agents for direct attacks on livestock or poultry. In the past, developed nations have actively developed biological weapons to target animals. The potential spectrum of bioterrorism ranges from isolated acts against individuals by individuals to tactical and strategic military attacks and state‐sponsored international terrorism intended to cause mass casualties in animals, humans or both. This review provides an overview of the past development and use of biological weapons and describes potential future attacks.  相似文献   
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Cross‐sucking and intersucking are considered abnormal behaviours in cattle and constitute a common problem in dairy farming. Cross‐sucking in calves is defined as sucking any body parts of another calf whereas intersucking in heifers and cows is defined as sucking the udder or udder area. The aim of this study was to determine the genetic variability for abnormal sucking behaviour by estimating genetic parameters and examining individual differences between sires with large progeny groups. By means of a questionnaire, cattle breeders in the federal state Lower Austria were requested to identify all currently kept animals which are known of either inter‐ or cross‐sucking (both defined as the same binary trait ‘sucking’ with 0 and 1 referring to the absence and presence of this abnormal behaviour) or allowing sucking (also treated as a binary trait, scored as 1 if an animal was known of allowing herd mates to suck and 0 otherwise). Records of 1222 farms and 13 332 dual purpose Simmental females aged between 21 and 700 days were investigated applying a linear animal model with fixed herd × year × season and random genetic animal effect and a threshold sire model with the herd × year × season effect being treated as random. In total, 8.6% and 4.1% of all calves/heifers were observed sucking and allowing sucking, respectively. Heritabilities of 0.040 ± 0.014 and 0.007 ± 0.006 (linear animal model) and 0.116 ± 0.041 and 0.026 ± 0.024 (threshold model) were found for the traits sucking and allowing sucking, respectively. Breeding values were estimated applying the same models for the trait sucking. Taking all 254 sires into account, the Pearson and Spearman correlation coefficients between breeding values estimated by linear animal and sire threshold model were 0.86 and 0.80. Thus, little difference was observed between the two methods.  相似文献   
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This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers.  相似文献   
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Objective : The purpose of this study was to investigate whether implantable loop recorders could be used in the diagnosis of unexplained collapse in dogs. Methods : The medical records of six dogs presented to the University of Liverpool Small Animal Teaching Hospital between May 2003 and October 2006 for further evaluation of intermittent syncopal episodes, collapse or episodic weakness, were reviewed. All these dogs underwent standard investigations and had implantable loop recorders placed. Results : A provisional diagnosis of supraventricular tachycardia was made in one dog, and diagnoses of exclusion of arrhythmogenic right ventricular cardiomyopathy and idiopathic epilepsy was made in two dogs. One dog suffered no further syncopal episodes, a diagnosis was not reached in another dog and the final dog was lost to follow‐up. Clinical Significance : The implantable loop recorder can be used successfully for the diagnosis of unexplained collapse in dogs.  相似文献   
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