猫尾草引种对比试验

对岷山猫尾草和引进的日本猫尾草、百万猫尾草、百丽莎猫尾草等8种猫尾草在海拔2500m的岷县寺沟乡奔直寺进行栽培试验，结果表明：8种猫尾草鲜草产量差异不显著（p〉0．05），但Goliatl猫尾草、日本猫尾草和岷山猫尾草产草量、鲜干比、植株高度均表现较好，可在高寒阴湿地区大力推广。     

岷县猫尾草新品种引种试验

为了筛选出最适合岷县高寒阴湿山区生境条件的优质高产猫尾草品种,引进普麦斯、骏马两个猫尾草新品种与当地岷山猫尾草进行了对比试验。结果表明:供试的3种猫尾草适应性强、抗寒耐湿、抗病虫害、生长期较长,都能在岷县高寒阴湿地区良好生长,但岷山猫尾草具有早熟、高产、抗寒性更好等优点,适宜在岷县及同类地区大面积推广,新引进的两个品种草产量相对较低、比较晚熟,还需要一个驯化和适应的过程。     

猫尾草不同品种的最佳刈割时期

通过测定猫尾草不同品种在孕穗——初穗期、抽穗期、盛花期、乳熟期、完熟期的蛋白质产量，确定了备品种的最佳刈割时期。结果表明，不同猫尾草品种，在不同生育时期刈割，草产量和营养价值不同；同一品种在不同时期刈割，草产量和营养价值亦不同。7个参试品种的最佳刈割时期分别为：岷山猫尾草和Climax为乳熟期；日本猫尾草，Baliza，Goliatl和Commonl为孕穗——初穗期；Richmand为完熟期。     

猫尾草不同品种的种子产量和适应性评价

测定了8个猫尾草品种在各试点的物候期、种子产量等指标.运用多点区域试验的方差分析法,分析了品种间、试点间、品种×试点互作间差异显著性;用通径分析法分析了种子产量各构成因素对种子产量的贡献大小.结果表明,Climax 和Coonl最适应于榆中,种子产量分别为543.76和476.95 kg/hm2;岷山、日本、Richmond 最适应于岷县点,种子产量分别为280.90, 156.51和150.34 kg/hm2;Barwa最适应于景泰点,种子产量达867.86 kg/hm2.在种子产量各构成因素中,单穗粒重对种子产量的影响最大.     

猫尾草新品系在甘肃省中部地区的生产性能和营养价值研究

为研究猫尾草新品系(T)在甘肃省中部地区的生产性能和营养价值,以川西猫尾草(CK1)和岷山猫尾草(CK2)为对照,对试验猫尾草材料3个生长年的株高、枝条数、草产量、粗蛋白(CP)含量、纤维含量等进行测定.结果 表明:(1)不同品系而言,新品系(T)生长3年的平均枝条数、鲜、干草产量、CP和粗脂肪(EE)含量均显著高于两...     

猫尾草营养价值及栽培利用研究进展

猫尾草是一种优良的长纤维牧草,日本、加拿大、美国对其研究和利用较多,国内种植面积也在逐年增加。对猫尾草的营养价值,栽培管理技术,不同熟期猫尾草品种产量和质量的表现,温度对猫尾草产量和质量的影响及加工贮藏等方面进行了综述。     

甘肃省中部地区猫尾草新品系的抗寒性研究

本试验以甘肃农业大学培育的猫尾草(Phleum pratense)新品系(T)为试验材料,'川西'猫尾草品种(CK1)和'岷山'猫尾草品种(CK2)为对照,研究3个材料在低温胁迫(0℃,—10℃,—20℃,—30℃)下生理生化指标的变化,明晰其抗寒性强弱,为培育高产优质、抗性强的猫尾草新品系打下基础.结果表明:不同低温...     

猫尾草的利用价值及在河西地区的种子生产

猫尾草（Common timothg）是禾本科猫尾草属，多年生长寿牧草，在我国东北、华北和西北地区均有栽培。猫尾草生育期为160～180天。播种当年每亩（667平方米）可收鲜草1500千克左右。第2年以后，草田每亩可收草3000千克左右，种子田每亩的种子产量为20～25千克。孕穗期猫尾草株高为60厘米左右，花期为100厘米左右，鲜干比为3．5：1。其叶量丰富，在始花期测定，叶量能占到鲜重的50％以上。     

行距、播量和施肥对岷山猫尾草种子产量的影响

在岷县闾井开展以行距、播量和施肥量3处理、3水平、2重复的正交试验,研究岷山猫尾草种子生产过程中合理的栽培管理措施。结果表明:施肥、播量对猫尾草种子产量有显著影响,在其它条件一致的情况下,岷山猫尾草合理的栽培管理措施组合为:播种量7.5 kg/hm2,氮肥150 kg/hm2,行距40 cm。     

猫尾草栽培与利用

猫尾草，属禾本科猫尾草属多年生草本植物，又名梯牧草。猫尾草属于喜冷凉、潮湿环境的冷地型牧草，原产于欧亚大陆的温带地区，遍及温带、寒温带和近北极气候区，主要分布在北纬40～50度寒冷湿润地区，我国新疆等地有野生种，是美国、俄罗斯、法国、日本等国家广泛栽培的主要牧草之一，我国东北、华北和西北均有栽培。     

Nutritional value of timothy haylage in Icelandic horses

Four mature Icelandic geldings were used in a balance trial to investigate the effect of stage of maturity of timothy (Pleum pratence L.) haylage fed at maintenance level on coefficients of total tract apparent digestibility (CTTAD), and nitrogen and energy metabolism in a 4 × 4 change-over arrangement of treatments. The content of fibre increased and crude protein content decreased with advancing stage of maturity. Very high CTTAD values were found for DM, OM, CP, CF, NDF and ADF in the first two cuts. Overall, there was a negative relationship between stage of maturity (p < 0.05) and the CTTAD of all measured dietary components. Nitrogen (N) intake, N losses in urine and N balance were affected (p < 0.05) by stage of maturity, while the N losses in the faeces were unaffected. There was a strong correlation (r² = 0.95) between N balance and water intake. Gross energy intake and losses in urine (as % of digestible energy intake) were unaffected by stage of maturity, while the energy balance was affected (p < 0.05). The digestible energy content of the timothy haylage studied ranged from 14.1 to 9.0 MJ/kg DM.

In conclusion, early-cut timothy haylage (stem elongation to flowering) has the energy content required to form the basis of diets for high-performing horses. Late-cut timothy haylage (seeding to late seeding), on the other hand, can be used to fulfil the energy and protein needs of maintenance-fed Icelandic horses.     

Protein quality and utilization of timothy, oat-supplemented timothy, and alfalfa at differing harvest maturities in exercised Arabian horses

To evaluate the protein quality and postgut N utilization of full-bloom timothy hay, oat-supplemented timothy-hay diets, and alfalfa hay harvested at different maturities, apparent whole tract N digestibility, urinary N excretion, and serum AA profiles were determined in light to moderately exercised Arabian horses. Six Arabian geldings (16.0 ± 0.3 yr; 467 ± 11 kg of BW) were randomly allocated to a 6 × 6 Latin square design. Diets included full-bloom timothy grass hay (G), G + 0.2% BW oat (G1), G + 0.4% BW oat (G2), mid-bloom alfalfa (A1), early-bloom alfalfa (A2), and early-bud alfalfa hay (A3). Forages were fed at 1.6% of the BW of the horse (as-fed). Each period consisted of an 11-d adaptation period followed by total collection of feces and urine for 3 d. Blood samples were taken on d 11 for analysis of serum AA concentrations. During the 3-d collection period, urine and feces were collected every 8 h and measured and weighed, respectively. Approximately 10% of the total urine volume and fecal weight per period was retained for N analyses. Fecal DM output was less (P < 0.05) in A1, A2, or A3 compared with G, G1, or G2. Apparent whole tract N digestibility was greater (P < 0.01) in A1, A2, and A3 compared with G, G1, or G2, and was greater (P < 0.05) in G1 and G2 compared with G. Nitrogen retention was not different from zero, and there were no differences (P > 0.05) in N retention among diets. Urinary N excretion and total N excretion were greater (P < 0.05) in A1, A2, and A3 compared with G, G1, or G2. Plasma concentrations for the majority of AA increased curvilinearly in response to feeding G, A1, A2, and A3 (quadratic, P < 0.05), with values appearing to maximize 2-h postfeeding. Although alfalfa N digestibility increased with decreasing harvest maturity, N retention did not differ and urinary volume and N excretion increased, indicating that postabsorptive N utilization decreased. In contrast, inclusion of oats at either 0.2 or 0.4% of the BW of the horse to timothy hay markedly enhanced N digestibility without increasing N excretion, indicating improvement in postgut N utilization. These findings indicate that feeding oat-supplemented timothy hay is more environmentally sustainable than feeding alfalfa to the horse at maintenance or under light to moderate exercise.     

Voluntary intake and digestibility of reed canarygrass and timothy hay fed to horses

Thousands of hectares of timothy (Phleum pretense L.) grown in the Mid-Atlantic region are infected by cereal rust mite (Abacarus hysterix) that causes discoloration and curling of leaves, decreased nutritional quality, and substantial decreases in yield. A decline in production of timothy hay can lower income for hay producers and cause horse owners to search for alternative hays. Low alkaloid reed canarygrass (Phalaris arundinacea L.) hay has potential as an alternative to timothy hay because it grows well in the Mid-Atlantic region, is believed to have a similar nutrient quality to timothy, and is not as susceptible to cereal rust mite. Eleven mature, stalled Thoroughbred geldings (549 +/- 12.1 kg) that were exercised daily were used to compare voluntary DMI and apparent nutrient DM digestibility of timothy and low-alkaloid Chiefton variety reed canarygrass hay. Horses were paired by age and BW and randomly assigned to timothy or reed canarygrass hay during a 14-d period to measure voluntary DMI followed by a 4-d period to measure apparent DM digestibility. Both hays met the minimum requirements for DE, CP, Ca, P, K, Fe, and Mn, but they did not meet the minimum requirements for Cu, Zn, and Na for horses at maintenance and averaging 550 kg of BW. Timothy hay seemed to have a lower CP concentration (14.4%) compared with reed canarygrass hay (17.1%) and a more desirable Ca:P ratio at 1.6:1 compared with 0.8:1 for reed canarygrass hay. Horses fed timothy consumed more hay (P <0.001) during the voluntary DMI period compared with horses fed reed canarygrass. Greater voluntary DMI of timothy occurred on d 1, 3, and 5 (P <0.05), but DMI was similar for other days. Apparent DM digestibility was greater in horses fed timothy hay by 9.6% compared with horses fed reed canarygrass hay (P <0.05). Horses fed timothy had greater DM digestibility of ADF (P = 0.001), NDF (P = 0.001), sugar (P = 0.05), and Ca (P = 0.001) but lower apparent DM digestibility of CP (P = 0.012) and crude fat (P = 0.004). Timothy hay was superior in voluntary DMI and apparent DM digestibility compared with low-alkaloid reed canarygrass hay fed to horses.     

The nutritive value for sheep of quackgrass and timothy hays harvested at two stages of growth

Thirty-two wethers were used to compare the nutritive value of Climax timothy (Phleum pratense L.) and quackgrass (Agropyron repens L. Beauv.) harvested at two stages of maturity, joint and early heading, and fed as hay. Crude protein was higher for quackgrass than for timothy (P less than .01). As maturity advanced, CP decreased (P less than .01), but NDF and ADL increased (P less than .01). Dry matter intake was similar between species but decreased by 8% with increasing maturity (P less than .01). Intake of NDF (g/kg.75) was similar for all hays. With increasing plant maturity, apparent digestibility decreased, the effect being more pronounced for quackgrass. Apparent digestibilities of DM and energy were slightly higher (P less than .06) for timothy, and those of CP and hemicellulose were higher for quackgrass (P less than .01). Apparent digestibilities of NDF, ADF, ADL, crude fiber and cellulose were similar between species. Dry matter intake and digestibility were correlated negatively with the ADL/ADF ratio of the hay (r = -.99, P less than .01), whereas CP intake and CP digestibility were correlated with CP of the hay (r = .99, P less than .01). The Lucas test estimated true protein digestibility at 88.1% and metabolic fecal protein at 29.4 g per kg of DM intake. During the growth trial, DM intake was similar between hays, but ADG of sheep was lower (P less than .01) for those fed hays at early heading vs those receiving hays at the joint stage of maturity. The feed to gain ratio was slightly lower for hays at joint (P less than .08). Under the climatic conditions of the 1988 growing season, the nutritive value of quackgrass was similar to that of Climax timothy.     

Energy expenditure for chewing in sheep fed timothy or sudangrass hay at the same intake level

In order to investigate the energy expended in chewing during eating and rumination in sheep fed timothy or sudangrass hay at the same intake level, the energy expenditure of the head was measured using the arterial-venous difference technique and that of the whole body was measured using an open-circuit, indirect respiration calorimeter. There was no difference in the per-chew energy expenditure between timothy hay and sudangrass hay during eating and rumination, but for both types of hay there was a difference in energy expenditure between eating (0.25 J per chew per kilogram body weight) and rumination (0.18 J per chew per kilogram body weight). There was no effect of time period after feeding on the energy expended in one chew during eating and rumination. On average, for a given type of hay, the energy expended in chewing during eating + rumination accounted for 4.9% of the daily energy expenditure of the whole body.     

Different responses in postprandial plasma ghrelin and GH levels induced by concentrate or timothy hay feeding in wethers

Ghrelin and growth hormone (GH) play a key role in regulating energy balance, metabolic hormone secretion and food intake. Ghrelin and GH responses to dietary compositions have not yet been fully clarified, although there may be significant relationships between dietary compositions and ghrelin and GH responses. In the present study, therefore, we assessed whether dietary compositions influence postprandial plasma ghrelin and GH levels in wethers. Four wethers were respectively fed concentrate (C) or timothy hay (R) for 14 days. The levels of total digestive nutrients (TDN) and crude protein (CP) were adjusted to be at the same level. The basal ghrelin in both groups was rapidly and significantly decreased after feeding. Although the decline of ghrelin levels in C was greater and shorter than that in R, no significant difference was observed in the area under the curve (AUC) or in the incremental area. The plasma GH levels were also rapidly and significantly decreased after feeding in both groups and a significant difference was observed between the two groups for AUC of GH. Interestingly, the circadian changes in the plasma ghrelin levels were close to those in the GH levels in C, but this was not the case in R. These data suggest that dietary compositions influence postprandial plasma ghrelin and GH levels, and that these differences may be caused by several factors, including nutrients and ruminal fermentation.