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The role of dietary fibre in pig production,with a particular emphasis on reproduction 被引量:17
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作者 Selene jarrett Cheryl j.ashworth 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第4期783-793,共11页
Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high f... Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems,particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production.Of particular potential value is the opportunity to use crude fibre concentrates as ’functional’ feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates. 展开更多
关键词 FIBRE PIG PREGNANCY Production REPRODUCTION
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日粮纤维在繁殖母猪生产中的重要作用 被引量:3
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作者 刘文峰(译) 潘雪男(审) +1 位作者 Selene jarrett Cheryl j.ashworth 《国外畜牧学(猪与禽)》 2020年第8期17-20,共4页
各种来源的纤维是猪日粮中的一种常见成分。纤维可以为养猪生产者提供一种利用本地生产的植物性原料(来自食品行业或饮料行业的副产品)的方法。含高水平纤维的日粮能够使动物产生饱腹感的价值早已得到公认。然而,向日粮中添加纤维可能... 各种来源的纤维是猪日粮中的一种常见成分。纤维可以为养猪生产者提供一种利用本地生产的植物性原料(来自食品行业或饮料行业的副产品)的方法。含高水平纤维的日粮能够使动物产生饱腹感的价值早已得到公认。然而,向日粮中添加纤维可能会降低猪的采食量,对正处于对营养需求有较高要求的生产阶段(如仔猪的生长期和母猪的哺乳期)的猪而言这显然是不利的。最近,人们发现纤维能给养猪生产带来鲜为人知的益处,特别是考虑到世界各地要求养猪业减少抗生素的使用量、对采用限饲的猪的福利关注以及需要确保此类生产系统对环境友好。例如,在日粮中添加纤维能够以一种可能会降低抗生素需求量的方式改变动物肠道中微生物菌群组成,受控制地添加某些种类的纤维可以减少在养猪生产过程中向环境排放的氮的数量,从而降低环境成本。具有特殊潜在价值的粗纤维浓缩物(crude fibre concentrates)有可能会被用作提高仔猪生长速度或改善其福利的“功能性”饲料添加剂。也许使用含高水平纤维的日粮最有可能提高母猪繁殖率。配种前提高日粮中纤维的含量可提高卵母细胞的成熟度、胚胎存活率和窝产仔数,为养猪生产者创造一种消费者可以接受的能够提高每头母猪可销售猪肉产量的方法,但产生这些益处的机制尚不明确。然而,血浆和卵泡液中关键激素和代谢产物的浓度的改变以及下丘脑饱腹感中枢对促性腺激素的分泌和表观遗传学的影响是主要影响因素。 展开更多
关键词 纤维 妊娠 生产 繁殖
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黏多糖增多症的眼部特征
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作者 ashworth j.L. Biswas S. +3 位作者 Wraith E. Lloyd I.C. j.ashworth 曹绪胜 《世界核心医学期刊文摘(眼科学分册)》 2006年第10期23-24,共2页
Aims:The mucopolysaccharidoses(MPS)are a heterogeneous group of rare disorders characterised by accumulation of glycosaminoglycans within multiple organ systems.This study aimed to determine the prevalence and severit... Aims:The mucopolysaccharidoses(MPS)are a heterogeneous group of rare disorders characterised by accumulation of glycosaminoglycans within multiple organ systems.This study aimed to determine the prevalence and severity of ocular complications in patients with MPS.Methods:Clinical ophthalmic features and electrodiagnostic results of 50 patients with a diagnosis of MPS were retrospectively reviewed.Results:A total of 79% of MPS IH patients had a visual acuity of less than 6/12 equivalent in their better eye,compared to 44% of MPS IH/S and 25% of MPS VI patients.In total,16% of MPS IH and 25% of MPS IH/S had severe corneal opacification,compared to 38% of MPS VI patients.16% of MPS IH patients had optic atrophy;21% of MPS VI patients had mild disc swelling,29% had markedly swollen discs,and 14% had optic atrophy.One patient with MPS IH,one with MPS IH/S and six with MPS VI had ocular hypertension.One MPS VI patient had glaucoma that required topical therapy.Nine patients with MPS IH had electrodiagnostic evidence of retinopathy,as did one MPS VI patient.Conclusions:Ocular complications causing significant reduction in vision are common in MPS.The majority of MPS I and MPS VI patients have corneal opacification,which can lead to difficulties in diagnosis and monitoring of glaucoma,optic disc changes,and retinopathy. 展开更多
关键词 黏多糖 视神经萎缩 眼部并发症 高眼压症 角膜混浊 视网膜病变 电生理检查 氨基葡萄糖 机体功能
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日粮纤维在繁殖母猪生产中的重要作用(续1)
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作者 刘文峰(译) 杨洋(译) +2 位作者 潘雪男(审) Selene jarrett Cheryl j.ashworth 《国外畜牧学(猪与禽)》 2020年第9期15-18,共4页
日粮纤维对母猪的行为、动物福利、免疫状态、氮排放量和繁殖性能具有一定的的影响。在母猪生产周期的不同阶段,如妊娠期、哺乳期,给其饲喂不同来源的纤维,会对母猪繁殖性能和所产仔猪的生产性能产生不同的影响,如果处理得当,猪场可从... 日粮纤维对母猪的行为、动物福利、免疫状态、氮排放量和繁殖性能具有一定的的影响。在母猪生产周期的不同阶段,如妊娠期、哺乳期,给其饲喂不同来源的纤维,会对母猪繁殖性能和所产仔猪的生产性能产生不同的影响,如果处理得当,猪场可从中获益。 展开更多
关键词 日粮纤维 卵母细胞 囊胚 母猪
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Associations between maternal vitamin D status and porcine litter characteristics throughout gestation
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作者 Claire Stenhouse Emma Hurst +1 位作者 Richard j.Mellanby Cheryl j.ashworth 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第2期806-813,共8页
Emerging evidence suggests an important role of vitamin D in the establishment and maintenance of pregnancy,and the regulation of foetal growth across mammalian species.However,the temporal changes in maternal vitamin... Emerging evidence suggests an important role of vitamin D in the establishment and maintenance of pregnancy,and the regulation of foetal growth across mammalian species.However,the temporal changes in maternal vitamin D sta-tus throughout gestation in the pig and the relationship between maternal vitamin D status and litter characteristics of interest across gestation remain poorly understood and under-investigated.The abundance of 25(OH)D in maternal plasma was quantified by HPLC–MS/MS at gestational days(GD)18,30,45,60 and 90(n=5–11 gilts/GD).Maternal plasma 25(OH)D concentrations significantly increased between GD18 and GD30(P<0.05).The relationship between maternal vitamin D metabolite concentrations and litter characteristics of interest including gilt weight,ovulation rate,mean litter weight,number of live foetuses,percentage prenatal survival,and sex ratio of the litter was assessed.Maternal 25(OH)D(P=0.059)concentrations tended to be positively associated with percentage prenatal survival on GD60.On GD90,maternal 25(OH)D(P<0.05)concentrations were inversely associated with gilt weight.Maternal plasma 25(OH)D concentrations were inversely associated with the percentage of male foetuses in the litter on GD90(P<0.05).This study has provided novel insights into temporal changes in maternal vitamin D status throughout ges-tation and the relationship between maternal vitamin D status and the economically important litter characteristics of gilt weight,percentage prenatal survival and percentage of male foetuses in the litter.Improving the understanding of the role of vitamin D across important developmental timepoints in relation to foetal growth is essential to improve reproductive success in livestock species. 展开更多
关键词 PORCINE PREGNANCY Vitamin D
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White (<i>Trifolium repens</i>L.) and Arrowleaf (<i>Trifolium vesiculosum</i>Savi) Clover Emergence in Varying Loblolly Pine (<i>Pinus taeda</i>L.) Tree Alley Spacings 被引量:1
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作者 Taylor C.Adams Dirk Philipp +6 位作者 David M.Burner john jennings Becky Mc Peake Amanda j.ashworth Daniel H.Pote joan M.Burke Robert Rhein 《American Journal of Plant Sciences》 2019年第4期659-669,共11页
Agroforestry systems have the potential to provide year-long income opportunities via the integrated forage or crop, timber, and livestock. Legumes are an attractive alternative option during the growing season when m... Agroforestry systems have the potential to provide year-long income opportunities via the integrated forage or crop, timber, and livestock. Legumes are an attractive alternative option during the growing season when more traditional forages may not be as productive. The objective of this study was to test the establishment of arrowleaf and white clover grown under varying pine tree alley widths. In 2011, existing forage was removed in 15-yr old loblolly pine tree row alleys of different widths (3.7, 4.9, 7.3, and 9.8 m), including an open area. Arrowleaf, as an annual, was replanted in 2012. Seedlings were counted twice/year, while dry matter was measured three times/year. Photosynthetically active radiation (PAR) was measured in all alley widths to compare light penetration through the canopy. Hot and dry conditions occurred throughout 2012, affecting results. In 2012 and 2013, the greatest PAR for most treatments was observed in June. Seedling counts for all treatments were greatest immediately after establishment, and gradually declined throughout the course of the study. Dry matter yields increased throughout the growing season, and were greatest in arrowleaf clover in the open area on all measurement dates;however, increased weed pressure and repeated flooding affected yields. This study demonstrated that clover establishment in shady wooded areas is possible, but only under suitable environmental conditions. 展开更多
关键词 WHITE CLOVER Arrowleaf CLOVER Dry Matter Yield Seedling Count Agroforestry
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Associations between testicular development and fetal size in the pig
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作者 Claire Stenhouse Yennifer Cortes-Araya +1 位作者 F.Xavier Donadeu Cheryl j.ashworth 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2022年第5期1340-1350,共11页
Background:Impaired reproductive performance is the largest contributing factor for the removal of boars from commercial systems.Intrauterine growth restricted piglets represent 25%of the total number of piglets born ... Background:Impaired reproductive performance is the largest contributing factor for the removal of boars from commercial systems.Intrauterine growth restricted piglets represent 25%of the total number of piglets born and have impaired reproductive performance.This study aimed to improve the understanding of temporal changes in testicular gene expression during testes development in fetuses of different size.The lightest and closest to mean litter weight(CTMLW)male Large White×Landrace littermates were collected at gestational days(GD)45,60 and 90(n=5-6 litters/GD).Results:Testes weight and testes weight as a percentage of fetal weight were not associated with fetal size at GD60 or 90.Fetal plasma testosterone was not associated with fetal size at GD90.There was no association between fetal size and seminiferous tubule area and number,number of germ or Sertoli cells per tubule.The lightest fetuses tended to have wider seminiferous tubules compared to the CTMLW fetuses at GD90(P=0.077).The testicular expression of KI67(P≤0.01)and BAX:BCL2 ratio(P=0.058)mRNAs decreased as gestation progressed.Greater SPP1 mRNA expression was observed at GD60 when compared with GD45 and 90(P≤0.05).Lower expression of DMRT1 and SPP1(P<0.01)mRNAs was observed in testes associated with the lightest fetuses compared to the CTMLW fetuses at GD90.Conclusions:These findings provide novel insights into the expression profiles of genes associated with testicular development and function.Further,these data suggest that programming of reproductive potential in IUGR boars occurs late in gestation,providing a platform for further mechanistic investigation. 展开更多
关键词 Fetal growth Intrauterine growth restriction(IUGR) PORCINE PREGNANCY TESTES
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