Breeding of rutabaga (Brassica napus var. napobrassica L. Reichenb.) based on biomarker selection for root maggot resistance (Delia radicum L.)     

Ivan Malchev  Ron Fletcher  Laima Kott 《Euphytica》2010,175(2):191-205

Cabbage root maggot (Delia radicum) is the most devastating and persistent pest for rutabaga (Brassica napus var. napobrassica) in all production areas in Canada. With the deregistration of terbufos (Counter^?) to combat maggot attack, only chlorpyrifos (Lorsban^?), an organophosphorous pesticide, remains and extensive use could lead to insecticide resistance. An unprotected crop would lead to serious domestic and export losses. Root maggot resistance from canola, that originated from the weedy crucifer, Sinapis alba, was transferred to rutabaga by standard hand crossing. A population of doubled haploids was developed from the F1s and screened in a high pressure root maggot rutabaga production field. Resistant and susceptible isolines were identified from different crossing groups and these isoline pairs were used to develop a biochemical selection protocol based on HPLC profiles where glucosinolates can be present as an aid to resistance breeding. Fourteen peaks in the HPLC profile were identified as markers and predictably varied between the more resistant and more susceptible lines. The 3–4 leaf stage was identified as the ideal stage for tissue extraction for profiling which is close to the stage when gravid female maggot flies seek host plants for oviposition utilizing olfactory signals from the host. Olfactory signals for Delia commonly are isothiocyanates which are volatile break down products of glucosinolates. The peaks in the HPLC profiles identified as markers for resistance contain glucosinolates and may be partially responsible for the plant-insect interaction. A predictive model is proposed as an aid to breeders for the development of root maggot resistant rutabaga lines.  相似文献   

Participation of Opioid Peptides in Sucking‐induced Oxytocin and Prolactin Secretions in Lactating Goats     

FA Bruna  EG De Di Nasso  M Soaje  RP Deis  RW Carón 《Reproduction in domestic animals》2010,45(5):796-802

The role of opioid peptides in the secretion of oxytocin (OT) and prolactin (PRL) induced by sucking was studied in goats. Seven goats were isolated with their kids (four singletons and three twins) in individual corrals 3–4 weeks after parturition. On day 1 of the experiment, the kids were separated from the does for 7 h and were weighed before and 15 min after being reunited with their mothers to assess the amount of milk obtained by sucking. The does were blood‐sampled 10 min before and at the end of the sucking period. On day 2, a similar protocol was followed, but naloxone was given immediately after the first blood sample. On day 3, the protocol was repeated but saline vehicle was injected instead of naloxone. On day 5, the naloxone experiment was repeated as on day 2. Milk ejection was evaluated as the difference in the weight of the kids before and after sucking for 15 min, and the maternal serum levels of OT and PRL were measured by radioimmunoassay. A significant decrease in the weight gain of the kids was obtained when the mothers were treated with naloxone on day 2. Consistently, serum levels of OT and PRL induced by sucking were significantly reduced; indicating that sucking‐induced OT secretion for milk ejection in lactating goats is facilitated by opioid peptides. In a second experiment performed in the same animals 10 days later, the administration of OT, immediately after naloxone administration, prevented the decrease in the weight gain induced by naloxone, suggesting that the effect of the opioid antagonist on milk ejection in goats is a result of a reduced OT secretion. The results of this study confirm the importance of sucking‐induced OT secretion for milk ejection in lactating goats, and indicate that OT and PRL secretion are regulated by opioid peptides in this species.  相似文献   

Spotted Knapweed Utilization by Sequential Cattle and Sheep Grazing     

Stacee L. Henderson  Tracy K. Mosley  Jeffrey C. Mosley  Rodney W. Kott 《Strength and Conditioning Journal》2012,65(3):286-291

Prescribed (or targeted) sheep grazing can effectively suppress the invasive perennial forb spotted knapweed (Centaurea stoebe L. ssp. micranthos [Gugler] Hayek). Some ranchers and other natural resource managers, however, resist using this weed management tool over concerns that sheep may consume too much of the graminoid standing crop, thereby decreasing its availability to cattle and wildlife and possibly harming graminoids with excessive defoliation. One potential approach to address these concerns is to graze spotted knapweed infestations first with cattle, immediately followed by sheep. We evaluated this sequential grazing strategy on foothill rangeland in western Montana, comparing sequential grazing at a moderate stocking rate in mid June (spotted knapweed in bolting stage) vs. mid July (spotted knapweed in late-bud/early flowering stage). Pastures (0.81 ha) were grazed with three yearling cattle for 7 d, immediately followed with 7 d of grazing by seven yearling sheep. Combined relative (i.e., utilization) of graminoids by cattle and sheep averaged 40% in June and July, safely within sustainable grazing use levels recommended for the site. Combined relative use of spotted knapweed by cattle and sheep also did not differ between June and July, averaging 62%. Previous research indicates that this degree of use is sufficient to suppress spotted knapweed. Our results indicate that prescribed sheep grazing can be applied immediately following cattle grazing in either June or July to suppress spotted knapweed without overusing desirable graminoids. Cattle and sheep will eat less graminoids and more spotted knapweed if cattle and sheep graze sequentially when spotted knapweed is in its late-bud/early flowering stage (mid July) rather than its bolting stage (mid June).  相似文献   

Experimental Eperythrozoon ovis infection in goats   总被引：1，自引：0，他引：1  

RW MASON  A. CORBOULD  P. STATHAM 《Australian veterinary journal》1989,66(7):221-222

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The determination of the level of Eperythrozoon ovis parasitaemia in chronically infected sheep and its significance to the spread of infection   总被引：1，自引：0，他引：1  

RW MASON  P STATHAM 《Australian veterinary journal》1991,68(3):115-116

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Pride without prejudice     

RW GEE 《Australian veterinary journal》1994,71(1):1-2

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Serum alpha-tocopherol and immune function in yearling ewes supplemented with zinc and vitamin E     

Hatfield PG  Robinson BL  Minikhiem DL  Kott RW  Roth NI  Daniels JT  Swenson CK 《Journal of animal science》2002,80(5):1329-1334

Yearling Targhee ewes (n = 24; not pregnant or lactating) were used in a 2 x 2 factorial arrangement of treatments to determine the effects of supplemental vitamin E (0 IU [0vitE] vs 330 IU vitamin E x ewe(-1) x d(-1) [+vitE]) and Zn (0 mg [0Zn] vs 140 mg Zn x ewe(-1) x d(-1) [+Zn]) on serum alpha-tocopherol concentrations, antibodies to parainfluenza type 3 (PI3), ewe BW, Zn liver concentrations, and serum alkaline phosphatase activity. Ewes were managed as one group, grazed native pasture, and had ad libitum access to white salt and water. Ewes that received supplemental vitamin E were orally dosed every other day with 660 IU of DL-alpha-tocopherol acetate in a gelatin capsule beginning on d 1 and continuing to d 63 of the study. Ewes that received Zn supplement were orally dosed every other day with 280 mg of Availa-Zn 100 (Zinpro Corp., Eden Prairie, MN, IFN 6-32-054) in gelatin capsules for 63 d. All ewes were vaccinated with killed PI3 on d 22 and 42. No interactions were detected (P > 0.35); however, serum alpha-tocopherol concentrations and PI3 antibody titer dilutions changed (P = 0.001) over the length of the study. Ewe BW change, serum alkaline phosphatase activity, and liver Zn concentrations did not differ (P > 0.22) between 0Zn and +Zn or 0vitE and +vitE ewes. Serum a-tocopherol tended to be higher (P = 0.08) in +vitE than 0vitE ewes and was numerically higher (P = 0.16) in +Zn than 0Zn ewes. Antibody titer dilutions were higher (P = 0.06) in 0Zn than +Zn ewes and did not differ (P = 0.83) between 0vitE and +vitE ewes. These results indicate that high levels of supplemental Zn may have a tendency to improve serum alpha-tocopherol concentrations but may have negative impacts on humoral immune function.  相似文献   

Optic neuropathy and retinopathy in closantel toxicosis of sheep and goats     

PA GILL  RW COOK  JG BOULTON  WR KELLY  B VANSELOW  LA REDDACLIFF 《Australian veterinary journal》1999,77(4):259-261

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Analysis of marker expression in porcine cell lines derived from blastocysts produced in vitro and in vivo     

Vackova I  Novakova Z  Krylov V  Okada K  Kott T  Fulka H  Motlik J 《The Journal of reproduction and development》2011,57(5):594-603

The present study was designed to extensively characterize cell lines derived from porcine blastocysts by several methodical approaches, including morphological observation, cytogenetic analysis, estimation of alkaline phosphatase activity and detection of specific marker expression at the mRNA/protein level. A comparison was made between the properties of cell lines isolated from in vivo- and in vitro-obtained blastocysts. Our results showed that 57.1% of the in vivo-obtained blastocysts attached to the feeder layer and that 33.3% of them started to grow in a monolayer. The percentage of attached in vitro-produced blastocysts was lower (24.6%), and only 6.9% of them started to grow. Outgrowths from the in vitro-produced blastocysts formed mainly trophectoderm or epithelial-like monolayer, whereas the in vivo-obtained blastocysts formed heterogeneous outgrowths that also contained cells with embryonic stem (ES)-like morphology. Detailed analyses showed that the primary outgrowths with ES-like morphology expressed the pluripotency markers OCT-4 and NANOG and revealed intensive alkaline phosphatase staining, while they did not express markers of differentiation. The majority of passaged cells, including those with ES-like morphology, lacked OCT-4 protein and revealed expression of specific differentiation markers (cytokeratin 18, lamins A/C, transferrin, α-fetoprotein and GATA-4), although they still expressed NANOG and exhibited weak alkaline phosphatase activity. Moreover, these cells spontaneously differentiated into neural, fibroblast or epithelial-like cells, even in the presence of leukaemia inhibitory factor. Our results show that complex analysis of markers of pluripotency as well as differentiation markers is necessary for proper interpretation of data in porcine embryonic stem cell studies.  相似文献