A longitudinal study of oestrous characteristics and conception in tie-stalled and loose-housed Swedish dairy cows     

S. Nyman  S. E. Malm  H. Gustafsson  B. Berglund 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2016,66(3):135-144

The presence and importance of visual oestrous symptoms and the relation to conception, breed, housing system and milk yield were studied. Data were collected from a Swedish research herd during a 16-year period. Local, secondary and primary oestrous symptoms and an overall oestrus intensity score (OI) were studied. Decreasing trends in oestrous expression and conception rates (CR), and an increase in CR with more intensive oestrus, from 24% at OI score one (very week) to 54% at OI score five (very strong) were observed. The mean interval from first to last observed oestrus symptom was long with a large variation (54?±?SD?=?32?h). Generally, irrespectively of housing system, Swedish Red cows had higher CR, more intensive oestruses and longer oestrus durations compared to Swedish Holstein cows. Local oestrous symptoms, with CR of 24–28%, were most frequently detected, which is why more attention should be paid to local oestrous symptoms.  相似文献   

Differences between primiparous and multiparous dairy cows in the inter-relationships between metabolic traits, milk yield and body condition score in the periparturient period     

Wathes DC  Cheng Z  Bourne N  Taylor VJ  Coffey MP  Brotherstone S 《Domestic animal endocrinology》2007,33(2):203-225

During the early postpartum period dairy cows mobilize fat and muscle to support lactation. This is associated with alterations in blood metabolite and hormone profiles which in turn influence milk yield and fertility. This study developed models to determine how metabolic traits, milk yield and body condition score were inter-related at different times in the periparturient period and to compare these relationships in primiparous (PP, n=188) and multiparous (MP, n=312) cows. Data from four previous studies which included information on blood metabolic parameters, parity, milk yield, body condition score and diet were collated into a single dataset. Coefficients of polynomial equations were calculated for each trait between -1 week pre-calving and week +7 postpartum using residual maximum likelihood modelling. The completed dataset was used in a multiple correlation model to determine how the best fit curves were related to each other over time. PP cows had higher concentrations of insulin-like growth factor-I and lower beta-hydroxybutyrate concentrations throughout, higher leptin concentrations pre-partum and both the peak in non-esterified fatty acids and the nadir in urea concentration occurred earlier after calving. These differences were associated with significantly lower milk production. Leptin concentrations fell at calving and were related to body condition score. Insulin was negatively correlated with yield in MP cows only. In MP cows the relationship between insulin-like growth factor-I and yield switched from negative to positive between weeks +4 and +7. Both beta-hydroxybutyrate and urea were positively related to yield in PP cows. In contrast, in MP cows beta-hydroxybutyrate was negatively correlated with yield and urea was strongly related to body condition score but not yield. These results suggest that there are differences in the control of tissue mobilization between PP and MP cows which may promote nutrient partitioning into growth as well as milk during the first lactation.  相似文献   

The association of hoof lesions at claw trimming with test-day milk yield in Danish Holsteins     

Ettema JF  Capion N  Hill AE 《Preventive veterinary medicine》2007,79(2-4):224-243

In a cross-sectional study, performed between October 2002 and April 2003 on 55 Danish dairy herds with 6161 predominantly Holstein Friesian cows the prevalence of 9 hoof lesions was determined.

All test-day yields (TDY) of kg energy corrected milk (ECM) in the lactation of diagnosis were recorded. For the purpose of including hoof lesions in a decision support model an attempt was made to aggregate the lesions into digital dermatitis (DD), other interdigital diseases (OID, infectious diseases other than DD) and hoof horn diseases (HHD, related to metabolic disorders and trauma). A division was made based on the stage of lactation in which the lesions were diagnosed; during the first 100 days in milk, between days 101 and 200 and between days 201 and 305. Associations between the presence of hoof lesions at trimming and milk production were analyzed by linear mixed modeling at the cow level, clustered within herd. The data of primiparous cows was analyzed separately from the multiparous cows.

Based on the associations between TDY and the individual lesions aggregated into HHD, this aggregation as initially planned could not be justified and was therefore not maintained. For OID the value of early diagnosis was apparent; an early diagnosis and early treatment (<101 DIM) was associated with either a positive value or a value less negative compared to a diagnosis and treatment in late lactation (201–305 DIM). This pattern was not as clearly present for the other lesions.  相似文献   

Prevalence of antimicrobial resistance among Salmonella on midwest and northeast USA dairy farms     

Ray KA  Warnick LD  Mitchell RM  Kaneene JB  Ruegg PL  Wells SJ  Fossler CP  Halbert LW  May K 《Preventive veterinary medicine》2007,79(2-4):204-223

The objective of this study was to determine the prevalence of antimicrobial resistance among Salmonella isolated from dairy herds in New York, Minnesota, Michigan, and Wisconsin, USA. Serogroup and antimicrobial susceptibility characteristics were determined for Salmonella from cattle and environmental samples collected during August 2000–October 2001 as part of a longitudinal study where 129 herds were visited at 2-month intervals. Salmonella isolates were tested (using a broth microdilution method) for susceptibility to amoxicillin/clavulanic acid, ampicillin, ceftiofur, ceftriaxone, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim/sulfamethoxazole. Of the 1506 isolates tested for minimum inhibitory concentrations to these 14 antimicrobial agents, 81.2% were pan-susceptible and for most herds (81.6%) the predominant antimicrobial resistance pattern was pan-susceptible. At least 1 Salmonella isolate resistant to 5 or more antimicrobial agents was found on 23.6% of herds. This resistance phenotype was most common among serogroups B and E1 and among samples from calves and farmer-designated sick cows. Resistant samples most frequently exhibited resistance to tetracycline, streptomycin, and/or ampicillin. No samples were resistant to ceftriaxone (though 13 were in the intermediate range), and very few samples were resistant to ciprofloxacin (n = 1), nalidixic acid (n = 5), or trimethoprim/sulfamethoxazole (n = 7).  相似文献   

干旱区小麦多功能高分子植物生长调节剂增产和品质改善试验研究   总被引：3，自引：0，他引：3  

张松林  赵首彩  董庆士  田侠  房妮 《中国农学通报》2005,21(9):263-265

以观测记录和拍照方式研究多功能高分子植物生长调节剂对小麦生长和繁殖、品质的影响,分别用土壤含水量为试剂保水指标,小麦生长、结实和产量指标、小麦品质指标以及经济效益指标与对照比较以评定试验效果。结果显示,施用试剂能够提高土壤保水率,有利于小麦的营养和结实生长,使小麦产量提高12.30%。小麦粗蛋白、赖氨酸和湿面筋含量均有显著提升,不利于人体健康的灰分和粗脂肪含量显著降低;经济效益有所提高,仅仅考虑增产就净增产值734.25￣794.85元/hm2。  相似文献   

Research on Mapping Method of Customer Need Information in Product Family Improvement     

CHEN Feng  YE Shi-qin  JIANG Yan  DAN Bin 《保鲜与加工》2007,(9):144-147

Aiming at ensuring that product family improvement is based on customer needs while taking full advantage of enterprise history database, firstly, customer needs in the product family improvement are expressed. Then a method of realizing the mapping of customer needs to functional requirements is presented, which is based on quality function development and association rule mining. Finally, an example illustrates the good application of the method.  相似文献   

深圳市河道水环境综合治理的典型   总被引：1，自引：2，他引：1  

朱闻博  胡仁贵  洪忠 《中国农村水利水电》2006,(9):28-31

通过对深圳市新洲河生态景观改造工程设计，摸索出一条融合现代水利工程、城市规划、风景园林、生态、水污染治理等多学科多专业进行城市河道综合治理工程设计方法，为探索深圳市河道生态改造打开思路。通过对深圳市新洲河两岸景观改造，将新洲河融入城市公共空间，使其成为居民的滨水休闲廊道；在截污的基础上，通过补水、水质净化等一系列措施，使河道水质变清，达到规定的地表水Ⅴ类标准；通过对河道的生态改造，恢复河道生态功能，提高水体自净能力，成为深圳市的生态景观廊道，达到人与自然的和谐相处。  相似文献   

农机具选型推广的方法和手段     

黄礼明 《现代农业装备》2006,(6):68-70

本文阐述了农机推广的操作程序并提出了农机推广过程中有关农机具改进的一些思路。  相似文献   

NY190柴油机研究开发     

朱景建 《拖拉机与农用运输车》2005,(4):72-73

概要介绍了在NY185柴油机基础上扩缸变形而设计的NY190柴油机的技术规格、主要结构、主要零部件的特点。该机较原机价格低、功率大、启动性能好、燃油消耗率低、质量可靠。  相似文献   

河北花生品质改良浅析   总被引：1，自引：0，他引：1  

齐丽雅  臧殿高  何孟霞  肖家雄 《花生学报》2006,35(2):37-40

阐述了花生品质的含义,针对存在问题提出改良花生品质的途径如营养元素、水分、气候因子等因素,为进一步改良花生品质提供依据。  相似文献