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201.
A crossbreeding program was conducted to evaluate the resistance status to Haemonchus contortus in reciprocal crossbred (F(1)) lambs and their Merino Land sheep (Ml) and Rhoen sheep (Rh) purebred counterparts. A total of 406 lambs were included in the study. Faecal egg counts (FEC) and haematocrit values (Hc) of all the lambs were collected 4 and 8 weeks after an artificial infection with H. contortus. FAMACHA scores were given at the same time. Worm counts of all lambs were obtained after slaughtering at 21 weeks of age. The Ml group consistently showed the highest body weights, daily weight gains and best carcass performances, whereas the Rh group showed the lowest results. Most of the body weight parameters in the F(1) group fell intermediately between the Ml and Rh groups, though the heterosis analysis of body weight and carcass parameters showed a tendency to favour the crossbreeding group Rh x Ml. The Rh group showed, on average, the highest FEC and the lowest Hc values compared to the Ml. However, the nematode counts were not significantly different between the pure breeds. In comparison, the worm counts of the Rh x Ml crosses were significantly different from those in the Ml x Rh crosses. A heterosis analysis showed that FEC, Hc and the worm count in the F(1) group favoured the crossbreeding group Rh x Ml. These results suggested that crossbreeding Rh to Ml sheep may be a suitable way of producing lambs with improved resistance to H. contortus infection without any negative effects on production traits. 相似文献
202.
Hetz C Bernasconi P Fisher J Lee AH Bassik MC Antonsson B Brandt GS Iwakoshi NN Schinzel A Glimcher LH Korsmeyer SJ 《Science (New York, N.Y.)》2006,312(5773):572-576
Accumulation of misfolded protein in the endoplasmic reticulum (ER) triggers an adaptive stress response-termed the unfolded protein response (UPR)-mediated by the ER transmembrane protein kinase and endoribonuclease inositol-requiring enzyme-1alpha (IRE1alpha). We investigated UPR signaling events in mice in the absence of the proapoptotic BCL-2 family members BAX and BAK [double knockout (DKO)]. DKO mice responded abnormally to tunicamycin-induced ER stress in the liver, with extensive tissue damage and decreased expression of the IRE1 substrate X-box-binding protein 1 and its target genes. ER-stressed DKO cells showed deficient IRE1alpha signaling. BAX and BAK formed a protein complex with the cytosolic domain of IRE1alpha that was essential for IRE1alpha activation. Thus, BAX and BAK function at the ER membrane to activate IRE1alpha signaling and to provide a physical link between members of the core apoptotic pathway and the UPR. 相似文献
203.
204.
Castiñeira Gómez Mdel M Brandt R Jakubowski N Andersson JT 《Journal of agricultural and food chemistry》2004,52(10):2953-2961
Elemental patterns are often used for the classification or identification of the origin of wines. A prerequisite is that the concentration of the elements is not strongly influenced by the addition of different substances such as yeast and fining products during the winemaking process. Inductively coupled plasma-mass spectrometry (ICP-MS) has been used in this study to determine in total 63 elements (including some nonmetals and the rare earth elements) in five German white wines from five regions of origin. The whole winemaking process was studied, from the must to the ready wine. Microwave acid digestion was used for sample preparation, and indium was added as internal standard for a semiquantitative analysis. Two winemaking processes were compared: with the addition of clarifying agents (bentonites) before and after the fermentation. The concentration of only a few elements such as Li, B, Mg, Ca, Rb, Cs, and Pb seems to be constant throughout the whole winemaking process (changes of <+/-50%) and are independent of the time of addition of the bentonites. When bentonites are added before fermentation, the concentration of other elements, such as V, Co, and Fe, remains constant. If bentonites are added after fermentation, the concentration of some other elements such as Sr, Zn, and Mn is nearly unaffected. These elements are therefore robust elements for origin studies in German white wines. 相似文献
205.
Brandt S Schoster A Tober R Kainzbauer C Burgstaller JP Haralambus R Steinborn R Hinterhofer C Stanek C 《Equine veterinary journal》2011,43(2):202-209
Reasons for performing the study: Equine hoof canker is a chronic proliferative pododermatitis of as yet unknown aetiology. Like equine sarcoid disease, canker is a therapy‐resistant disorder characterised by hyperkeratosis, acanthosis and a marked tendency to recur. Hypothesis: There is an association of sarcoid‐inducing bovine papillomaviruses of types 1 and 2 (BPV‐1, BPV‐2) with hoof canker disease. Methods: Using PCR‐based techniques, we assessed canker tissue, intact skin and/or peripheral blood mononuclear cells (PBMCs) of 25 canker‐affected horses for the presence of sarcoid‐associated BPV‐1 and ‐2. Results: Conventional PCR revealed BPV‐1/‐2 DNA in 24/24 canker, 12/13 skin and 10/11 PBMC DNA isolates. Using inverse PCR, full‐length BPV episomes were detected in 1/5 canker specimens. Sequencing of viral early and late genes amplified from canker, intact skin and PBMC DNA of 2 cases revealed an overall identity of 98% to BPV‐1. Viral DNA loads amounted to ≤16 copies per cell in canker tissue and intact skin, and to ≤0.35 copies per PBMC, as determined by quantitative PCR. Using RT‐PCR, the viral major oncogene E5 was shown to be transcribed in 2/4 canker tissue specimens and 5/7 PBMC isolates. Immunocapture PCR from 7 canker and 6 skin extract supernatants revealed capsomere‐associated viral DNA in one canker and one skin sample. Hoof tissue, skin and PBMCs collected from 13 individuals with no signs of canker or BPV‐related malignancies scored negative throughout the experiments. Conclusion: These findings suggest that the observed presence of BPV‐1/‐2 in canker‐affected horses is not coincidental but indicative of an active contribution to hoof canker disease. Potential relevance: The use of antivirals and/or immune modulators may help improving canker therapy. 相似文献
206.
Assessing the usefulness of B‐mode and colour Doppler sonography,and measurements of circulating progesterone concentrations for determining ovarian responses in superovulated ewes 下载免费PDF全文
MEF Oliveira IF Ribeiro MGK Rodriguez GS Maciel JF Fonseca FZ Brandão PM Bartlewski 《Reproduction in domestic animals》2018,53(3):742-750
The main goal of this study was to assess the usefulness of two imaging modalities, namely the B‐mode and colour Doppler sonography, and serum progesterone (P4) concentrations for determining the ovarian response in superovulated ewes. Twenty‐four sexually mature Santa Inês ewes underwent the superovulatory treatment consisting of eight injections of porcine FSH (total dose of 200 or 133 or 100 mg; n = 8 ewes/total dose) given at 12‐hr intervals and initiated 48 hr before CIDR ® (Pfizer Inc., Auckland, New Zealand) removal. Six days after natural mating, the ovaries of all donor ewes were visualized and examined with transrectal ultrasonography and then with videolaparoscopy to identify and enumerate corpora lutea (CL ) and luteinized unovulated follicles (LUF s). Jugular blood samples were collected just prior to ovarian examinations. The total number of CL (r = .78 and 0.83, p < .0001) and LUF s (r = .74 and 0.90, p < .0001) enumerated using the B‐mode and colour Doppler ultrasonographic technique, respectively, were correlated with that ascertained by videolaparoscopy. Circulating concentrations of P4 were related directly to the number of healthy CL (r = .73, p = .0002) and inversely to the number of prematurely regressing CL (r = ?.46, p = .03), but the accuracy of predicting the number of short‐lived CL with serum P4 concentrations was very poor. The present results indicate that ultrasonographic imaging and serum P4 measurements on the day of embryo recovery are useful indicators of total/normal CL numbers and both ultrasonographic techniques can be used to quantify LUF s in superovulated ewes. 相似文献
207.
Steven A. Barben Bryan G. Hopkins Von D. Jolley Bruce L. Webb Brandt A. Nichols Emily A. Buxton 《Journal of plant nutrition》2013,36(8):1144-1163
Three hydroponic experiments were conducted with Russet Burbank potato to elucidate zinc (Zn) and manganese (Mn) relationships and associated interactions with other nutrients at different levels of phosphorus (P). Except when P was optimal, root Mn concentration was reduced at optimal solution Zn relative to deficient or excessive Zn levels. Shoot Mn generally increased with augmented solution Zn. As solution Zn increased, root P declined while shoot P and copper (Cu) and root iron (Fe) and Cu increased. Increasing solution Mn generally decreased Zn in all plant tissues—especially in roots. The Mn influence on plant P, Cu, and Fe concentrations was nearly opposite the Zn impact, indicating that Zn and Mn have counter effects. Partitioning between root and shoot micronutrient concentrations occurred when available P was either deficient or excessive, which may also help explain poor plant health and adverse micronutrient relationships in potato when available P is not optimally maintained. 相似文献
208.
Impact of Buserelin Acetate or hCG Administration on the Day of First Artificial Insemination on Subsequent Luteal Profile and Conception Rate in Murrah Buffalo (Bubalus bubalis) 下载免费PDF全文
AK Pandey SPS Ghuman GS Dhaliwal SK Agarwal JB Phogat 《Reproduction in domestic animals》2016,51(4):478-484
This study was designed to investigate the impact of buserelin acetate (BA) or human chorionic gonadotropin (hCG) administration on the day of first artificial insemination (AI) on subsequent luteal profile (diameter of corpus luteum (CL) and plasma progesterone) and conception rate in Murrah buffalo. The present experiment was carried out at two locations in 117 buffalo that were oestrus‐synchronized using cloprostenol (500 μg) administered (i.m.) 11 days apart followed by AI during standing oestrus. Based on treatment (i.m.) at the time of AI, buffalo were randomly categorized (n = 39 in each group) into control (isotonic saline solution, 5 ml), dAI‐BA (buserelin acetate, 20 μg) and dAI‐hCG (hCG, 3000 IU) group. Out of these, 14 buffalo of each group were subjected to ovarian ultrasonography on the day of oestrus to monitor the preovulatory follicle and on days 5, 12, 16 and 21 post‐ovulation to monitor CL diameter. On the day of each sonography, jugular vein blood samples were collected for the estimation of progesterone concentrations. All the buffalo (n = 117) were confirmed for pregnancy on day 40 post‐ovulation. The conception rate was better (p < 0.05) in dAI‐BA (51.3%) and dAI‐hCG (66.7%) groups as compared to their control counterparts (30.8%). Furthermore, the buffalo of dAI‐hCG group had improved (p < 0.05) luteal profile, whereas the buffalo of dAI‐BA group failed (p > 0.05) to exhibit stimulatory impact of treatment on luteal profile when compared to control group. In brief, buserelin acetate or hCG treatment on the day of first AI leads to an increase in conception rate; however, an appreciable impact on post‐ovulation luteal profile was observed only in hCG‐treated Murrah buffalo. 相似文献
209.
Archaeological surveys in woodland have always been problematicand many woodlands contain an unrecorded archaeological resource.For other types of rural landscape, aerial photographs are oftenused to map archaeological features but woodland cover has alwaysimpeded such disclosure. Remote sensing methods are rapidlyevolving and are used both within forestry and archaeologicaldisciplines for a range of applications. This paper considersthe exciting application of the remote sensing technique ofairborne Light Detection and Ranging (LiDAR) to reveal archaeologicalevidence previously hidden below a woodland canopy. Our researchshows how different types of woodland canopy and understoreyvegetation greatly influence the effectiveness of the LiDARto perform these surveys. A simple, visual vegetation mappingassessment is tested and its ability to predict the potentialof the LiDAR considered. This work highlights the importanceof vegetation awareness when considering both a new LiDAR surveyfor a woodland, and when interpreting the data. Simple estimatesof LiDAR penetration of the woodland canopy and understoreyvegetation can be used to predict the effectiveness of a LiDARsurvey in disclosing archaeological evidence and aid the interpretationof results. 相似文献
210.
Fandamu P Marcotty T Brandt JR Duchateau L Speybroeck N Dolan TT Berkvens D 《The Onderstepoort journal of veterinary research》2007,74(1):37-43
A comparison of mean corpuscular volume (MCV) and packed cell volume (PCV) was made between cattle undergoing lethal and non-lethal reactions following experimental infections with the apicomplexan protozoa, Theileria parva Katete. This work confirmed that anaemia occurs in infected animals. However, the fall in PCV was steeper in lethal reactions compared to non-lethal reactions. Our results show that animals with initially lower MCV values are more prone to fatal reaction, despite having normal PCV profiles. The study also found that small red blood cells are more likely to be infected with T. parva. These findings suggest that animals with a higher proportion of small red blood cells in circulation will be more likely to succumb to T. parva infections. The potential for using MCV as a predictor of the outcome of infection challenge is discussed. 相似文献