Development of an estrus synchronization protocol for beef cattle with short-term feeding of melengestrol acetate: 7-11 synch     

Kojima FN  Salfen BE  Bader JF  Ricke WA  Lucy MC  Smith MF  Patterson DJ 《Journal of animal science》2000,78(8):2186-2191

An estrus synchronization protocol (7-11 Synch) was developed to synchronize the first follicular wave and timing of ovulation in postpartum beef cows. In Exp. 1, follicular development and timing of ovulation in response to the following protocol were evaluated. Beef heifers (n = 12) and cows (n = 6), at random stages of the estrous cycle, were fed melengestrol acetate (MGA; .5 mg x animal(-1) x d(-1)) for 7 d and injected with PGF2alpha (PG; 25 mg) on the last day of MGA. A second injection of PG was administered 11 d after cessation of MGA. After the second injection of PG, estrus was synchronized in 6/12 heifers and 3/6 cows. The interval to estrus in heifers and cows was 54 and 64 h, respectively (P > .10). All animals exhibiting estrus ovulated first-wave follicles. Animals that failed to respond to the second injection of PG were in estrus later than 6 d after cessation of MGA and had corpora lutea that were unresponsive to the injection of PG. Based on the variation in interval to estrus following the first PG injection on the last day of MGA feeding in Exp. 1, an injection of GnRH (100 microg) was added to the protocol 4 d after the cessation of MGA to ensure ovulation or luteinization of dominant follicles and synchronization of first-wave follicular development. This revised protocol was termed "7-11 Synch." In Exp. 2, two estrus synchronization protocols were compared. Multiparous beef cows were stratified by breed and postpartum interval and randomly assigned to the 7-11 Synch (n = 44) or Select Synch protocols (GnRH injection followed by PG injection 7 d later; n = 45). Timing of estrus after the last PG injection (0 h) ranged from 42 to 102 h in the 7-11 Synch group and -30 to 114 h in the Select Synch group. Eight cows (18%) in the Select Synch group exhibited estrus 30 h before to 18 h after PG. Synchronized estrus peaked between 42 and 66 h after the last PG injection, and a maximum number of cows were in estrus at 54 h for both treatment groups. Synchrony of estrus from 42 to 66 h was greater (P < .05) in 7-11 Synch (91%: 41/44) than in Select Synch cows (69%: 31/45). Artificial insemination pregnancy rate from 42 to 66 h was greater (P < .05) in the 7-11 Synch group (66%: 29/44) than in the Select Synch group (40%: 18/45). In summary, the 7-11 Synch protocol improved synchrony of estrus without reducing fertility. This protocol has potential future application for fixed-time AI in beef cattle production systems.  相似文献   

Plesiomonas shigelloides--an uncommon cause of diarrhoea in cats?     

Foster G  Patterson T  Pennycott T  Cheasty T 《The Veterinary record》2000,146(14):411

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The effect of quality of grass and maize silage on the intake and performance of beef cattle     

R.M. Kirkland  D.C. Patterson 《Livestock Science》2006,100(2-3):179-188

A study was undertaken to evaluate the effects of incorporating high (HMS) and low (LMS) maturity maize silages into diets based on low (LGS) and high (HGS) feed value grass silages offered to beef cattle. Seventy-two continental cross-bred steers were used in a 14-week continuous design, randomised block experiment. The six treatments were arranged as a 2 × 3 factorial design incorporating the LGS and HGS offered as the sole forage, along with each of the two grass silages offered in a 60:40 ratio (DM basis) with the HMS and LMS. All diets were supplemented with 3 kg/head/day concentrates. Total daily DM and metabolisable energy intakes were higher (P < 0.001) for diets based on HGS compared to those based on LGS. Intakes were similar (P > 0.05) between diets containing LMS and HMS, both of which were higher (P < 0.001) than diets containing grass silage as the sole forage. Highest DM intakes were recorded with a mixture of HGS and HMS (P < 0.05 or greater). Cattle offered diets containing HGS had higher live-weight gain (P < 0.05), final live weight, carcass gain and carcass weight (P < 0.001) than those offered diets containing LGS. Feed conversion efficiency, assessed on a carcass gain basis, was poorer (P < 0.05) with diets containing LGS compared with those containing HGS, though differences between diets containing either LMS or HMS and GS as the sole forage were not significant (P > 0.05).  相似文献   

INTERNATIONAL CHEMISTRY     

Patterson AM 《Science (New York, N.Y.)》1929,69(1795):531-536

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Antibodies to Borrelia burgdorferi in New England horses: serologic survey   总被引：5，自引：0，他引：5  

L C Marcus  M M Patterson  R E Gilfillan  P H Urband 《American journal of veterinary research》1985,46(12):2570-2571

Twelve of 50 randomly selected horses from areas endemic for Borrelia burgdorferi had indirect fluorescent antibody titers of 1:8 to 1:2,048 against B burgdorferi. One of 50 horses from nonendemic areas had a titer of 1:8. This difference in the number of horses seropositive for B burgdorferi (P less than 0.002) and our finding that seropositive horses did not have agglutinating antibodies against potentially cross-reacting Leptospira spp indicated that horses in endemic areas were exposed to B burgdorferi and that the spirochete induced an antibody response in the horses.  相似文献   

PHYSICS AT THE DETROIT MEETING OF THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE     

Patterson GW 《Science (New York, N.Y.)》1897,6(148):649-655

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The relationship between site factors and white ash (Fraxinus americana L.) decline in Massachusetts     

H. Woodcock  W.A. Patterson III  K.M. Davies Jr. 《Forest Ecology and Management》1993,60(3-4):271-290

Forest inventory records incorporating individual tree data are an important source of information about the extent and severity of past rates of forest decline, thus providing a temporal perspective for contemporary observations. We demonstrate the potential of this approach by using continuous forest inventory (CFI) data to reconstruct the extent, severity, pattern of development and site-factor associations for white ash decline in Massachusetts. White ash (Fraxinus americana L.) increased in basal area on Massachusetts CFI plots at about 1.5% per year from 1962 to 1979. Ash decline is, however, locally severe. Plot decline status was estimated, based on vigor rating, and growth and mortality rates of white ash. Plots with a mean change in basal area per year of −0.5% and/or with a mean vigor rating of 2.0 (on a scale of 0–4) were classified as ‘decline’. Using these criteria, 20% of the 82 CFI plots with 10% total basal area of white ash in 1962 were classified as ‘decline’ in both 1979 and 1991. These results suggest that statewide there has been no net loss of ash basal area since 1962. The total forest area affected by ash decline has not increased in the past decade.

Analyses of the CFI data indicate that decline was most prevalent on mesic sites, high on the landscape and/or on steep slopes. Such sites are potentially subject to large fluctuations in soil moisture availability during drought periods. Relationships identified between the prevalence of ash decline and site factors were further evaluated within a 2 ha intensived study site in the center of a 13 ha white ash stand affected by ash decline in 1990. Decline was heterogeneously distributed within the stand, with declining trees most frequent on the ‘decline-prone’ site-type identified through CFI plot analyses.  相似文献   

Ex vivo Biomechanical Comparison of V‐Loc 180® Absorbable Wound Closure Device and Standard Polyglyconate Suture for Diaphragmatic Herniorrhaphy in a Canine Model          下载免费PDF全文

Megan M. Templeton DVM  Alexander I. Krebs DVM  Diplomate ACVS  Karl H. Kraus DVM  MS  Diplomate ACVS  Cheryl S. Hedlund DVM  MS  Diplomate ACVS 《Veterinary surgery : VS》2015,44(1):65-69

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Reporting standards for biofilter performance studies   总被引：1，自引：0，他引：1  

John Colt  Jonathan Lamoureux  Richard Patterson  Gary Rogers   《Aquacultural Engineering》2006,34(3):377-388

The development of standardized rating and design procedures for biological filters will require that filter performance be evaluated and reported in a standardized manner. This article recommends draft reporting standards for biofilter performance studies. It is important that critical parameters are defined and reported in a standard manner, both in terms of definition, variable names, and units. Depending on the type and scale of an experiment, reporting of certain parameters will be either mandatory or optional. Basic principles of experimental design, statistical analysis, and randomization must be followed. Experimental protocols are recommended to ensure the accuracy of measured or computed parameters. The development of this reporting standard is being organized through the Standards and Reporting Committee of the Aquaculture Engineering Society (AES). It is anticipated that a revised version of these standards will be incorporated into the Guide to Authors for Aquacultural Engineering.  相似文献   

Tricyclic Guanidine Alkaloids from the Marine Sponge Acanthella cavernosa that Stabilize the Tumor Suppressor PDCD4     

Tanja Grkovic  Johanna S. Blees  Magdalena M. Bayer  Nancy H. Colburn  Cheryl L. Thomas  Curtis J. Henrich  Megan L. Peach  James B. McMahon  Tobias Schmid  Kirk R. Gustafson 《Marine drugs》2014,12(8):4593-4601

A cell-based high-throughput screen that assessed the cellular stability of a tumor suppressor protein PDCD4 (Programmed cell death 4) was used to identify a new guanidine-containing marine alkaloid mirabilin K (3), as well as the known compounds mirabilin G (1) and netamine M (2). The structures of these tricyclic guanidine alkaloids were established from extensive spectroscopic analyses. Compounds 1 and 2 inhibited cellular degradation of PDCD4 with EC₅₀ values of 1.8 μg/mL and 2.8 μg/mL, respectively. Mirabilin G (1) and netamine M (2) are the first marine natural products reported to stabilize PDCD4 under tumor promoting conditions.  相似文献