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1.
The effect of using Propionibacterium acnes, (EqStim®)a as an adjunct to conventional therapy in the treatment horses with Equine Respiratory Disease Complex (ERDC) was evaluated. Of the 45 horses entering the study, 25 received EqStim® and conventional therapy while 20 horses (negative controls) received a carrier solution of 12.5% ethanol-saline and conventional therapy. At the end of the 14 day test period, 96% (24/25) of the horses treated with EqStim® and conventional therapy showed clinical improvement or complete recovery as compared to the control group in which 35% (7/20) of the horses (treated with conventional therapy and carrier) showed clinical improvement or complete recovery.  相似文献   

2.
Orally administered ivermectinawas 100% effective against experimentally induced 11-day-old infections of Parascaris equorum (L3) in 2 trials. In 4 additional trials there was 98% efficacy of ivermectin treatment against induced 28-day-old infections of P. equorum (L4). In 2 trials with natural infections of ascarids, invermectin paste had 93% efficacy against immature P. equorum and 100% efficacy against the adult. One of the latter 2 trials also emphasized the potential problem of reinfection.  相似文献   

3.
基因组选择(genomic setection,GS)是继标记辅助选择(marker-assisted selection,MAS)之后发展起来的新一代畜禽遗传评估的新方法.近年来,不少学者从各方面对GS在畜禽育种中的运用进行了研究,结果发现,与其他方法相比,GS优势明显,是当前畜禽遗传育种领域的研究热点.作者系统地阐述了GS估计染色体片段效应的方法及其准确性比较,详细介绍了影响GS准确性的因素、GS的经济效益,以及世界各国学者研究GS在实际育种中的应用情况,最后简述了中国畜禽育种开展GS策略所面临的挑战及其展望.  相似文献   

4.
家禽的生物学特性和经济学特性(如繁殖率高、繁殖周期短、单位成本低、育种材料易于携带和运输以及经济节约型规模化养殖)使家禽业成为畜牧业中最先进的行业。在所有动物物种中,家禽的育种程度最高。所有牲畜品种中,家禽具有最高的饲料转化率,且无论在发展中国家还是发达国家,禽肉的消费比率逐年增长。据世界粮农组织动物生产及卫生司预测,发展中国家禽肉消费年增长率将由目前的25%增加到2030年的34%。另一方面,家禽产业结构的快速调整已成为威胁家禽遗传资源的重要因素。目前,全世界已有30%的家禽品种濒临灭绝,9%的家禽品种已经灭绝。此外,遗传多样性丢失、消费涉及的动物福利以及环境问题也对家禽资源产生威胁。因此,家禽业是政府决策过程中权衡各种因素的理想案例,如食品安全与农业生物多样性、公共投资与私人投资、规模化养殖与小规模养殖、创造就业机会与自谋职业、标准和食品安全与食物多样性等。本文重点关注家禽遗传多样性、家禽育种、家禽研究的公共投资和私人投资以及食品安全等方面的问题。  相似文献   

5.
富集型鸡笼的发展和应用   总被引:1,自引:0,他引:1  
为了改善笼养蛋鸡的福利状况,富集型鸡笼产生并被广泛应用。作者介绍了富集型鸡笼的产生和发展概况,并对富集型鸡笼在生产实践中对蛋鸡的影响进行了探讨,评价了未来富集型鸡笼在中国的应用前景。  相似文献   

6.
Maternal recognition of pregnancy refers to the requirement for the conceptus(embryo and its associated extraembryonic membranes) to produce a hormone that acts on the uterus and/or corpus luteum(CL) to ensure maintenance of a functional CL for production of progesterone;the hormone required for pregnancy in most mammals.The pregnancy recognition signal in primates is chorionic gonadotrophin which acts directly on the CL via luteinizing hormone receptors to ensure maintenance of functional CL during pregnancy.In ruminants,interferon tau(IFNT) is the pregnancy recognition signal.IFNT is secreted during the peri-implantation period of pregnancy and acts on uterine epithelia to silence expression of estrogen receptor alpha and oxytocin receptor which abrogates the oxytocin-dependent release of luteolytic pulses of prostaglandin F2-alpha(PGF) by uterine epithelia;therefore,the CL continues to produce progesterone required for pregnancy.Pig conceptuses secrete interferon delta and interferon gamma during the peri-implantation period of pregnancy,but there is no evidence that they are involved in pregnancy recognition signaling.Rather,pig conceptuses secrete abundant amounts of estrogens between Days 11 to 15 of pregnancy required for maternal recognition of pregnancy.Estrogen,likely in concert with prolactin,prevents secretion of PGF into the uterine venous drainage(endocrine secretion),but maintains secretion of PGF into the uterine lumen(exocrine secretion) where it is metabolized to a form that is not luteolytic.Since PGF is sequestered within the uterine lumen and unavailable to induce luteolysis,functional CL are maintained for production of progesterone.In addition to effects of chorionic gonadotrophin,IFNT and estrogens to signal pregnancy recognition,these hormones act on uterine epithelia to enhance expression of genes critical for growth and development of the conceptus.  相似文献   

7.
8.
Workouts of 980 unraced 2-year-old Thoroughbred racehorses at major U.S. auctions were videotaped using digital high-speed video equipment (ie, slow motion) and studied for signs of extraneous foreleg motion.a Extraneous foreleg motion included, but was not limited to: 1) hyper rotation of the cannon bone on an axis parallel to the plane of the running surface (ie, moving in sagittal plane; hoof hitting an elbow in extreme cases) and perpendicular to the direction of the racetrack longitudinally; and 2) foreleg flight patterns not symmetrical and/or not parallel to the vector of the forward momentum of the horse's center of gravity (eg, winging, paddling, and/or wobbling at joints). Experienced Thorough bred racehorse industry videographers and gait analysis researchers were trained and used as film reviewers who rated foreleg motion on a scale of 1 to 5, with 1 indicating little or no extraneous motion, 3.5 indicating average extraneous motion (relative to the other unraced 2-year-olds at these auctions and to more than 20,000 similar horses at similar auctions over the past 10 years), and 5 indicating extreme extraneous motion (ie, at least 1 standard deviation or more from the mean). Because these were subjective ratings, only the more extreme rankings were used for comparison purposes in this study—that is, a minority (15.3%) of the overall study population.

A group of 73 horses with “good” foreleg motion had ratings from 1 to 3. A group of 77 horses with “bad” foreleg motion had ratings from 4 to 5. The subsequent North American racing performance of horses with good and bad foreleg motion was compared. Both groups had similar average velocity and similar distribution patterns of the velocities of the workouts, so the differences between the groups that are discussed in this study were not caused by different overall workout velocities.

Extraneous foreleg motion was shown to be related to subsequent racing earnings and the level of racing competition achieved. Horses with good foreleg motion (as defined herein) earned more and had greater stakes-level success than horses with bad foreleg motion. For example, the median earnings per start of horses with good foreleg motion was 83% higher than those of horses with bad foreleg motion, and horses with good foreleg motion were 58% more likely to win a top race (ie, one designated as a “graded” stakes) than horses with bad foreleg motion. However, the “good movers” raced less overall than the “bad movers.”

A secondary finding of this study is that although there is a widely held industry belief that horses with high action or bad foreleg motion are more suited to turf racing, horses with good foreleg motion were more likely than horses with bad foreleg motion to race at least once on turf, and, among horses to race on turf, horses with good foreleg motion were more likely than horses with bad foreleg motion to win and to finish “in the money” (ie, at least third).  相似文献   


9.
Background: Creep feeding is used to stimulate piglet post-weaning feed consumption.L-Glutamine(GLN) is an important source of fuel for intestinal epithelial cells.The objective of this study was to determine the impact of creep feeding and adding GLN or AminoGut(AG;containing glutamine + glutamate) to pre-and post-weaning diets on pig performance and intestinal health.Litters(N = 120) were allotted to four treatments during 14–21 d of lactation: 1) No creep feed(NC,n = 45);2) creep fed control diet(CFCD,n = 45);3) creep fed 1% GLN(CFGLN,n = 15);4) creep fed.88% AG(CFAG,n = 15).After weaning,the NC and CFCD groups were sub-divided into three groups(n = 15 each),receiving either a control nursery diet(NC-CD,CFCD-CD) or a diet supplemented with either GLN(NC-GLN,CFCD-GLN) or with AG(NC-AG,CFCD-AG).Litters that were creep fed with diets containing GLN or AG also were supplemented with those amino acids in the nursery diets(CFGLN-GLN,CFAG-AG).Glutamine was added at 1% in all three post-weaning diet phases and AG was added at.88% in phase 1 and 2 and at.66% in phase 3.Results: Feed conversion(feed/gain) showed means among treatment means close to significance(P = 0.056) and Tukey's test for pairwise mean comparisons showed that Pigs in the CFGLN-GLN group had the best feed conversion(feed/gain) in the first three-week period post-weaning,exceeding(P = 0.044) controls(CFCD-CD) by 34%.The NC-AG group had(P = 0.02) the greatest feed intake in the last three week of the study,exceeding controls(CFCD-CD) by 12%.CFGLN-GLN,CFCD-GLN and sow reared(SR) pigs had the greatest(P = 0.049) villi height exceeding the CFCD-AG group by 18%,20% and 19% respectively.The CFAG-AG group had the deepest(P = 0.001) crypts among all treatments.CFGLN-GLN,CFCD-GLN and SR groups had the greatest(P = 0.001) number of cells proliferating(PCNA) exceeding those in the NC-CD group by 43%,54% and 63% respectively.Sow reared pigs showed the greatest(P = 0.001) intestinal absorption capacity for xylose and mannitol.Conclusion: Supplementation of creep feed and nursery diets with GLN and/or AminoGut in the first three week improved feed conversion possibly due to improved intestinal health.  相似文献   

10.
Improving efficiency of sow productivity: nutrition and health   总被引:2,自引:0,他引:2  
This reviews research focused to understand the nutrient requirement and balance to meet the needs of fetal growth,mammary growth,and milk production.This summary will handle how feeding strategies can be adjusted according to the nutrient needs for a sow to enhance productivity and health.Most research data used in this summary are based on the studies conducted by the authors between 1996 and 2013.Nutrient requirements of sows are affected by stage of gestation and parity of sows.Dietary antioxidant concentrations need to be re-evaluated for its sufficiency in sow diets especially to prevent excessive oxidative stress during late gestation and lactation.When feeding sows,consideration of phase feeding of gestating sows and parity feeding of lactating sows could enhances production longevity and health of sows.Use of selected nutrients and additives seems to help productivity and health of sows.  相似文献   

11.
To test whether mineral recommendations for horses are likely to guarantee adequate mineral provision for tapirs (Tapirus spp.), we investigated the apparent absorption (aA) of macro and micro‐minerals in 18 tapirs from five zoological institutions in a total of 24 feeding trials with total faecal collection. Samples of feeds and faeces were analysed for Ca, P, Mg, Na, K, Fe, Cu and Zn. The resulting aA coefficients and the linear relationships of apparently absorbable dietary mineral content to total dietary mineral content (per 100 g dry matter) were compared with data for domestic horses. While there were no apparent differences in the absorption patterns for P, K, Na, Fe, Cu or Zn, the absorption of both Ca and Mg was distinctively higher in tapirs than in horses. Tapirs are browsers that are adapted to a diet of higher Ca content and higher Ca:P ratio than equids, and high absorptive efficiency for Ca might have evolved to ensure that high dietary Ca concentrations do not lead to the binding of dietary P in the intestine, making it unavailable for hindgut microbes. Similar to other hindgut fermenters, in tapirs, absorption coefficients for Ca increased with dietary Ca:P ratio, and urinary Ca:creatinine ratios increased with dietary Ca. Several zoo diets used were deficient in one or more minerals. When compared with faeces of free‐ranging animals, faeces of zoo animals had higher concentrations of most minerals, probably indicating a lesser diluting effect of indigestible fibre in zoo animals.  相似文献   

12.
The intestine and the gut-associated lymphoid tissue(GALT) are essential components of whole body immune defense,protecting the body from foreign antigens and pathogens,while allowing tolerance to commensal bacteria and dietary antigens.The requirement for protein to support the immune system is well established.Less is known regarding the immune modifying properties of individual amino acids,particularly on the GALT.Both oral and parenteral feeding studies have established convincing evidence that not only the total protein intake,but the availability of specific dietary amino acids(in particular glutamine,glutamate,and arginine,and perhaps methionine,cysteine and threonine) are essential to optimizing the immune functions of the intestine and the proximal resident immune cells.These amino acids each have unique properties that include,maintaining the integrity,growth and function of the intestine,as well as normalizing inflammatory cytokine secretion and improving T-lymphocyte numbers,specific T cell functions,and the secretion of IgA by lamina propria cells.Our understanding of this area has come from studies that have supplemented single amino acids to a mixed protein diet and measuring the effect on specific immune parameters.Future studies should be designed using amino acid mixtures that target a number of specific functions of GALT in order to optimize immune function in domestic animals and humans during critical periods of development and various disease states.  相似文献   

13.
This article presents a comprehensive review on the achievements obtained in the past a few decades and the prospects in aquaculture and aquafeed industry in China. The total production of aquaculture in China increased from 2.38 million tons in 1978 to 36 million tons in 2008, growing 15 times in 30 years.  相似文献   

14.
Background: Integration of behavioral observations with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems.Brahman-influenced(BR;n = 64) and Gelbvieh × Angus(GA;n = 64) heifers consumed either toxic endophyte-infected tall fescue(E+) or one of two nontoxic endophyte-infected tall fescue(NT) cultivars during two yr.Heifers were weighed at midpoint and termination of grazing.Grazing behavior(grazing,resting in the shade,lying,or standing without grazing) was recorded(n = 13 visual observations per yr in June and July) for each pasture.During yr 2,exit velocity(EV) and serum prolactin(PRL) were determined.Results: Grazing behavior was influenced(P 0.05) by an interaction between fescue cultivar and breed type.Gelbvieh × Angus heifers assigned to E+ pastures had the lowest percentage of animals grazing and the largest percentage of animals resting in the shade.Brahman-influenced heifers had faster EV(P 0.001) than GA heifers(0.52 vs.0.74 ± 0.04 s/m,respectively).Body weight(BW) was affected(P 0.01) by an interaction of tall fescue cultivar and d,and an interaction of tall fescue cultivar and breed type.Heifers grazing NT pastures were heavier(P 0.01) than heifers grazing E+ pastures at midpoint and termination.Gelbvieh × Angus heifers grazing NT pastures were heavier(P 0.01) than GA and BR heifers grazing E+ and BR heifers grazing NT pastures.An interaction of forage cultivar and breed type occurred on serum PRL(P 0.01).Conclusion: Collectively fescue cultivar,EV,and concentrations of serum PRL were associated with grazing behavior.Heifers grazing NT pastures were observed to be grazing more than heifers assigned to E+ pastures,regardless of breed type,which may have contributed to changes in BW and average daily gain(ADG) in heifers.Integration of behavioral observations along with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems.  相似文献   

15.
The availability of local feed resources in various seasons can contribute as essential sources of carbohydrate and protein which significantly impact rumen fermentation and the subsequent productivity of the ruminant.Recent developments,based on enriching protein in cassava chips,have yielded yeast fermented cassava chip protein(YEFECAP) providing up to 47.5% crude protein(CP),which can be used to replace soybean meal.The use of fodder trees has been developed through the process of pelleting;Leucaena leucocephala leaf pellets(LLP),mulberry leaf pellets(MUP) and mangosteen peel and/or garlic pellets,can be used as good sources of protein to supplement ruminant feeding.Apart from producing volatile fatty acids and microbial proteins,greenhouse gases such as methane are also produced in the rumen.Several methods have been used to reduce rumen methane.However,among many approaches,nutritional manipulation using feed formulation and feeding management,especially the use of plant extracts or plants containing secondary compounds(condensed tannins and saponins) and plant oils,has been reported.This approach could help todecrease rumen protozoa and methanogens and thus mitigate the production of methane.At present,more research concerning this burning issue-the role of livestock in global warming-warrants undertaking further research with regard to economic viability and practical feasibility.  相似文献   

16.
Nutritional factors influence regulation of growth hormone (GH), insulin-like growth factor-Ⅰ (IGF-Ⅰ) and insulin (INS) in fish. But so far there are no published studies describing how single indispensable amino acids and different carbohydrate to lipid ratios influence those systems. Therefore, the present study aimed to evaluate whether arginine (Arg) intake and carbohydrate to lipid ratios would affect expression of GH, IGF-Ⅰ and INS in largemouth bass.  相似文献   

17.
Background: Post-production fractionation of wheat distillers grains with solubles(DDGS) increases their crude protein content and reduces their fiber content.This experiment was conducted to determine the effects of fractionation of wheat DDGS on apparent total tract digestibility(ATTD) and performance when fed to broiler chicks(0–21 d).Methods: A total of 150,day-old,male broiler chicks(Ross-308 line;Lilydale Hatchery,Wynyard,Saskatchewan) weighing an average of 49.6 ± 0.8 g were assigned to one of five dietary treatments in a completely randomized design.The control diet was based on wheat and soybean meal and contained 20% regular wheat DDGS.The experimental diets contained 5,10,15 or 20% fractionated wheat DDGS added at the expense of regular wheat DDGS.Results: The ATTD of dry matter and gross energy were linearly increased(P 0.01) as the level of fractionated wheat DDGS in the diet increased.Nitrogen retention was unaffected by level of fractionated wheat DDGS(P 0.05).Weight gain increased linearly(P = 0.05) as the level of fractionated wheat DDGS in the diet increased.Feed intake,feed conversion and mortality were unaffected by level of fractionated wheat DDGS in the diet(P 0.05).Conclusions: Post-production fractionation of wheat DDGS improves their nutritional value by lowering their fiber content and increasing their content of crude protein and energy.These changes in chemical composition supported increased weight gain of broilers fed wheat DDGS.  相似文献   

18.
Humans and animals are in regular and at times close contact in modern intensive farming systems.The quality of human-animal interactions can have a profound impact on the productivity and welfare of farm animals.Interactions by humans may be neutral,positive or negative in nature.Regular pleasant contact with humans may result in desirable alterations in the physiology,behaviour,health and productivity of farm animals.On the contrary,animals that were subjected to aversive human contact were highly fearful of humans and their growth and reproductive performance could be compromised.Farm animals are particularly sensitive to human stimulation that occurs early in life,while many systems of the animals are still developing.This may have long-lasting impact and could possibly modify their genetic potential.The question as to how human contact can have a positive impact on responses to stressors,and productivity is not well understood.Recent work in our laboratory suggested that pleasant human contact may alter ability to tolerate various stressors through enhanced heat shock protein(hsp) 70 expression.The induction of hsp is often associated with increased tolerance to environmental stressors and disease resistance in animals.The attitude and consequent behaviour of stockpeople affect the animals' fear of human which eventually influence animals' productivity and welfare.Other than attitude and behaviour,technical skills,knowledge,job motivation,commitment and job satisfaction are prerequisites for high job performance.  相似文献   

19.
Four experimental diets were fed to turbet to examine the effect of fish bydrolyside and ultra filtered fish hydrolysafe on growth performate feed utilization and growth regulation using diets low in dietary fish meal inclusion. Diets A, B contained 3.7%,1.2% fish hydrolysate to replace fish meal respectively and the fish hydrolysate in two diets was ultra filtered to keep low molecular weight compounds. The diets A,  相似文献   

20.
A six-week growth trial was conducted to compare the effects of different feeding strate- gies of dietary immunostimulants on the growth and immunity of white shrimp Litopenaeus vannamei (4.70 ±0.20g). Shrimps were fed with diet containing glycyrrhizin continuously, containing β -glucan continuously, discontinuously (seven days with diet containing β -gluseven days with diet without -glucan; two days with diet containing β-glucan following five days with diet without -glucan),  相似文献   

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