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31.
The presence of benzimidazole-resistant strains of equine small strongyles was confirmed in horses at two properties in north west England by a series of faecal egg counts and larval cultures after treatment with mebendazole. A trail formulation of mebendazole in combination with piperazine citrate gave greater reductions in faecal egg counts than mebendazole alone but was much less effective than pyrantel embonate or dichlorvos. 相似文献
32.
A total of 35 worm-free lambs were infected with a strain of Ostertagia circumcincta isolated earlier from sheep in Cheshire, England, and found to be resistant to thiabendazole (TBZ). When patency was established the sheep were divided into groups of six, and dosed orally with either TBZ (44 mg kg-1, 88 mg kg-1), fenbendazole (FBZ; 5 mg kg-1) or levamisole (7.5 mg kg-1) or not treated. Three of the remaining five animals were dosed with FBZ at 10 mg kg-1. Egg hatch tests, post-dosing faecal egg counts and post-mortem worm counts confirmed resistance to TBZ, and a degree of side-resistance to FBZ was also revealed. Only levamisole gave the clearance expected of modern anthelmintics. 相似文献
33.
Two experiments were conducted to determine the minimal effective dose during lactation and site of action of N-methyl-d,l-aspartic acid (NMA) for elicitation of release of luteinizing hormone (LH) in female pigs. In the first experiment, three doses of NMA were given to lactating primiparous sows in which endogenous LH was suppressed by suckling of litters. In the second experiment, ovariectomized gilts were pretreated with estradiol benzoate or porcine antisera against GnRH to suppress LH and then given NMA to determine if it elicited secretion of LH directly at the anterior pituitary or through release of GnRH. In experiment 1, 3 lactating sows (17 +/- 1.5 d postpartum) were each given three doses of NMA (1.5, 3.0 and 5.0 mg/kg body weight [BW]; IV) on 3 consecutive days in a Latin Square design. Blood samples were collected every 10 min from -1 to 1 hr from injection of NMA. NMA at 1.5 and 3.0 mg/kg did not affect (p greater than .5) secretion of LH; however, 5 mg NMA/kg elicited a 114% increase (p less than .001) in circulating levels of LH during 1 hr after treatment. In experiment 2, 8 ovariectomized gilts were given either estradiol benzoate (EB; 10 micrograms/kg BW; IM n = 4) to suppress release of GnRH or porcine antiserum against GnRH (GnRH-Ab; titer 1:8,000; 1 ml/kg BW; IV; n = 4) to neutralize endogenous GnRH. Gilts infused with GnRH-Ab were given a second dose of antiserum 24 hr after the first. Gilts were then given NMA (10 mg/kg BW; IV) 33 hr after EB or initial GnRH-Ab. Blood samples were drawn every 6 hr from -12 to 24 hr from EB or GnRH-Ab treatments, and every 10 min from -2 to 2 hr from NMA. Serum LH declined (p less than .001) after EB (from 1.87 +/- .2 ng/ml at 12 hr before EB to 0.46 +/- .02 ng/ml during 24 hr after EB) and GnRH-Ab (from 1.97 +/- .1 to 0.59 +/- .02 ng/ml). In gilts treated with EB, the area under the curve (AUC) for the LH response (ng.ml-1.min) 1 hr after NMA (38.7 +/- 3) was significantly greater (p less than .01) than the 1 hr prior to NMA (21.3 +/- 1.5). Treatment with NMA had no effect (p greater than .5) on secretion of LH in gilts infused with GnRH-Ab.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
34.
Jocelyn R Holt Lina Bernaola Kadie E Britt Chirs McCullough Morgan Roth Jennie Wagner Max Ragozzino Leslie Aviles Zhilin Li Forest Huval Manoj Pandey Benjamin W Lee Megan Asche Abigail Hayes Abigail Cohen Adrian Marshall Hannah E Quellhorst Rachel V Wilkins Valerie Nguyen Jacqueline Maille Rachel K Skinner John J Ternest Sarah Anderson Scott W Gula Kayleigh Hauri Julius Eason Megan Mulcahy Scott Lee James Michael Villegas Patricia Shorter 《Journal of insect science (Online)》2020,20(5)
Every year, the Student Debates Subcommittee (SDS) of the Student Affairs Committee (SAC) for the annual Entomological Society of America (ESA) meeting organizes the Student Debates. This year, the SAC selected topics based on their synergistic effect or ability to ignite exponential positive change when addressed as a whole. For the 2019 Student Debates, the SAC SDS identified these topic areas for teams to debate and unbiased introduction speakers to address: 1) how to better communicate science to engage the public, particularly in the area of integrated pest management (IPM), 2) the influential impacts of climate change on agriculturally and medically relevant insect pests, and 3) sustainable agriculture techniques that promote the use of IPM to promote food security. Three unbiased introduction speakers gave a foundation for our audience to understand each debate topic, while each of six debate teams provided a strong case to support their stance or perspective on a topic. Debate teams submitted for a competitive spot for the annual ESA Student Debates and trained for the better part of a year to showcase their talents in presenting logical arguments for a particular topic. Both the debate teams and unbiased introduction speakers provided their insight toward a better understanding of the complexities of each topic and established a foundation to delve further into the topics of science advocacy and communication, climate change, and the many facets of integrated pest management. 相似文献
35.
Inferring spatial structure from population genetics and spatial synchrony in demography of Baltic Sea fishes: implications for management 下载免费PDF全文
Örjan Östman Jens Olsson Johan Dannewitz Stefan Palm Ann‐Britt Florin 《Fish and Fisheries》2017,18(2):324-339
The spatial structure of species is important for their dynamics and evolution, but also for management and conservation. There are numerous ways of inferring spatial structures, and information from multiple methods is becoming more common to examine how different processes shape the spatial structures of species to improve fish management. Here, we investigate the spatial structure of a suite of Baltic Sea fish species based on the following: (i) spatial (presumably neutral) genetic differentiation, reviewed from the literature, and (ii) spatial synchrony in abundance changes from time series of fishery‐independent surveys, which we currently find to be underused given the amount of data available. For each of these two methods, species were classified as having a distinct, continuous or no/weak spatial structure. In addition, based on each source of information, we estimated the spatial scale of management units for species. The results show that only among species confined to the coastal zone the two sources of information yielded a congruence of the spatial structure (displaying a continuous spatial structure). In contrast, offshore species show weak spatial genetic structure but stronger spatial structure of synchrony in abundance. Based on this, we suggest that population genetic structure and synchrony in abundance should be used as complementary information as they reflect different spatial processes and suggest that management actions should differ with respect to scale depending on the management targets applied. We propose similar analysis should be applied to areas outside the Baltic Sea, and other stock identification methods, to improve management of fish resources. 相似文献
36.
Hormones within the somatotropin cascade influence several physiological traits, including growth and reproduction. Active immunization against growth hormone-releasing factor (GRFi) initiated at 3 or 6 mo of age decreased weight gain, increased deposition of fat, and delayed puberty in heifers. Two experiments were conducted to investigate the effects of GRFi on puberty and subsequent ovulation rate in gilts. Crossbred gilts were actively immunized against GRF-(1-29)-(Gly)2-Cys-NH2 conjugated to human serum albumin (GRFi) or against human serum albumin alone (HSAi). In Exp. 1, gilts were immunized against GRF (n = 12) or HSA (n = 12) at 92 +/- 1 d of age. At 191 d of age, antibody titers against GRF were greater (P < .05) in GRFi (55.5 +/- 1.3%) than in HSAi (.4 +/- 2%) gilts. The GRFi decreased (P < .05) BW (86 +/- 3 vs 104 +/- 3 kg) by 181 d of age and increased (P < .05) backfat depth (15.7 +/- .4 vs 14.8 +/- .4 mm) by 130 d of age. At 181 d of age, GRFi reduced the frequency of ST release (1.0 +/- .5 vs 5.0 +/- .5, peaks/24 h; P < .0001) and decreased (P < .01) ST (1.1 +/- .06 vs 1.7 +/- .06 ng/mL), IGF-I (29 +/- 2 vs 107 +/- 2 ng/mL), and insulin concentrations (3.5 +/- .2 vs 6.3 +/- .2 ng/mL). The GRFi decreased (P < .05) feed conversion efficiency but did not alter age at puberty (GRFi = 199 +/- 5 d vs HSAi = 202 +/- 5 d) or ovulation rate after second estrus (GRFi = 10.7 +/- .4 vs HSAi = 11.8 +/- .5). In Exp. 2, gilts were immunized against GRF (n = 35) or HSA (n = 35) at 35 +/- 1 d of age. The GRFi at 35 d of age did not alter the number of surface follicles or uterine weight between 93 and 102 d of age, but GRFi decreased (P < .05) ovarian weight (.41 +/- .08 vs 1.58 +/- .4 g) and uterine length (17.2 +/- 1.1 vs 25.3 +/- 2.3 cm). Immunization against GRF reduced (P < .05) serum IGF-I (GRFi = 50 +/- 4 vs HSAi = 137 +/- 4 ng/mL) and BW (GRFi = 71 +/- 3 vs HSAi = 105 +/- 3 kg) and increased (P < .05) backfat depth (GRFi = .38 +/- .03 vs HSAi = .25 +/- .02 mm/kg). Age at puberty was similar in GRFi and HSAi gilts, but ovulation rate was lower (P < .05) after third estrus in GRFi (11.3 +/- .8) than in HSAi (13.8 +/- .8) gilts. Thus, GRFi at 92 or 35 d of age decreased serum ST, IGF-I, and BW in prepubertal gilts without altering age of puberty. However, GRFi at 35 d of age, but not 92 d of age, decreased ovulation rate. These results indicate that alterations in the somatotropic axis at 1 mo of age can influence reproductive development in pubertal gilts. 相似文献
37.
Departments of animal science were established in agricultural colleges of public universities just over 100 yr ago, shortly before the founding of today's American Society of Animal Science. These departments and colleges have been remarkably resilient, changing little structurally. Yet, the future portends significant changes in these departments and colleges in response to shifts in how public higher education is financed and how society views the roles of animals in providing food and companionship. Funding for public higher education will continue to decline as a percentage of government appropriations. Public universities will garner more funding from gifts, endowments, grants, contracts, and tuition but will be held more accountable than today by public officials. Departments of animal science will retain strong constituencies and will be major units of most agricultural colleges; however, their students and faculty will be more diverse. Departments of animal science will focus on more species of animals and on a greater role of animals in society. Disciplines of faculty members in departments of animal science will become broader, and research projects will be more complex and have longer horizons, ultimately focused more on sustainability. Departments will share more resources across state and national boundaries, and there will be less duplication of effort regionally. Departments of animal science will continue to be important academic units of universities into the 22nd century. 相似文献
38.
Investigation showed that the common causes of death in North Ronaldsay lambs were trauma due to behavioural patterns and starvation/hypothermia due in part to poor condition of the ewes. 相似文献
39.
During the summer and fall of 1987, sows from eight herds in three states were assigned randomly to receive either a combination of 400 IU of pregnant mare's serum gonadotropin with 200 IU of hCG (P.G. 600) or no treatment at weaning. A treatment x parity interaction was observed for days to first estrus after treatment and percentage anestrus (percentage of sows not achieving estrus within 10 d after weaning). Relative to primiparous control sows, primiparous sows given P.G. 600 expressed estrus sooner (P less than .02) after weaning (6.0 vs 7.8 +/- .6 d) and exhibited less (P less than .02) postweaning anestrus (15.6 vs 29.2 +/- 4.0%). Second parity sows that received P.G. 600 showed estrus sooner (P less than .06) than second-parity control sows (4.7 vs 6.4 +/- .7 d). Days to first estrus after treatment did not differ between groups for parity-three and older sows, and percentage anestrus was not different between treatments for parity-two and older sows. The herd X treatment interaction was significant for percentage recycled (percentage of successfully mated sows that returned to estrus), subsequent farrowing rate, and subsequent number of pigs born dead. Number of pigs born alive was lower for sows treated with P.G. 600 than for control sows (10.55 vs 10.10 +/- .18; P less than .02). In summary, treatment of sows weaned in the summer and fall with P.G. 600 had decreased days to postweaning estrus in parity-one and -two sows and reduced frequency of postweaning anestrus in primiparous sows. 相似文献
40.
Summary Examination by culture of single faecal samples from 120 domestic dogs in the Vom area of Nigeria showed 22 (18 per cent) of the animals to be excreting Salmonella organisms. One of the dogs yielded two and another three different serotypes. The total number of Salmonella serotypes isolated in the survey was 21. Dogs may be important in Nigeria as agents for the transmission of salmonellosis to man and domestic livestock.
Aislamiento De Salmonelas De Perros En Vom, Nordeste De Nigeria
Resumen Se cultivaron materias fecales de 120 perros domésticos en el área de Vom, nordeste de Nigéria. Los exámenes dieron como resultado el aislamiento de salmonelas del 18 por ciento de animales examinados. En uno de los perros se identificaron dos serotipos distintos y en otro tres. El número total de serotipos aislados fue de 21. Se concluye, que los perros de Nigéria podrian ser importantes como agentes transmisores de salmonelosis a humanos y otros animales domésticos.
Salmonelles Chez Les Chiens, A Vom, En Nigeria
Résumé L'examen par culture d'échantillons de matières fécales de 120 chiens domestiques de la région de Vom, en Nigéria, a montré que 22 d'entre eux, soit 18 p. 100, excrétaient des Salmonelles.Un des chiens hébergeait deux sérotypes et un autre trois sérotypes différents. Le nombre total des sérotypes isolés a été de 21. Les chiens peuvent donc constituer au Niger un facteur de transmission des Salmonelloses aux hommes et aux animaux domestiques.相似文献