5种不同牧草在奶牛瘤胃中降解特性的研究

本试验旨在研究苜蓿、燕麦草、羊草、稻草和玉米青贮共5种牧场常用的粗饲料瘤胃降解特性.试验选用体重为(650±25) kg的3头装有永久性瘤胃瘘管的泌乳中期荷斯坦牛,采用尼龙袋法评定其DM、OM、CP、NDF和ADF的瘤胃降解特性和有效降解率.结果表明:①5种粗饲料中苜蓿的DM、OM、CP有效降解率显著高于其他粗饲料,均在50％以上;稻草这3个指标的瘤胃有效降解率均最低;②玉米青贮的NDF、ADF的瘤胃有效降解率均最高,苜蓿均为最低.综合考虑,苜蓿的瘤胃降解特性最好,奶牛饲喂价值最高,玉米青贮和燕麦草次之,而稻草最差.     

绵羊常用蛋白质饲料在瘤胃的降解特性

通过尼龙袋法测定了１０种常用蛋白质饲料在绵羊瘤胃内干物质和蛋白质降解率。结果表明：在所测的１０种饲料中，豆粕、花生饼和苜蓿草粉的干物质和蛋白质降解率最高；菜籽饼、棉籽饼、芝麻饼和胡麻饼居中；葵花饼、鱼粉和玉米蛋白粉的干物质和蛋白质降解率最低。饲料的蛋白质降解率（Ｙ）与其干物质降解率（Ｘ）表现出密切相关：Ｙ＝０．８１Ｘ＋１２．２５（ｒ＝０．８５，Ｐ〈０．０５）。根据饲料降解特性，对降解率高的饼粕类应     

常规与非常规粗饲料在奶牛瘤胃中的降解特性研究

旨在探讨非常规粗饲料(玉米芯、毛豆荚壳)与奶牛常用粗饲料(苜蓿干草、玉米青贮)在奶牛瘤胃中的降解规律,试验选用3只装有永久性瘤胃瘘管的荷斯坦奶牛,采用尼龙袋法测定4种粗饲料的干物质(DM)、粗蛋白(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃降解规律。结果表明:1)苜蓿干草和毛豆荚壳的CP含量分别为17.55%和11.10%,且苜蓿干草显著高于毛豆荚壳(P<0.05);玉米芯和玉米青贮的CP含量分别为2.97%和8.41%,且玉米芯显著低于玉米青贮(P<0.05);玉米芯的NDF和ADF含量显著高于其他3种粗饲料(P<0.05),达到79.98%和43.35%。2)苜蓿干草的DM有效降解率最高(P<0.05),由高到低依次为苜蓿干草、毛豆荚壳、玉米青贮和玉米芯。毛豆荚壳的CP有效降解率显著高于其他3种粗饲料(P<0.05),由高到低依次为毛豆荚壳、苜蓿干草、玉米青贮和玉米芯。苜蓿干草的NDF有效降解率显著高于毛豆荚壳(P<0.05),玉米青贮和毛豆荚壳无显著差异(P>0.05);玉米芯的ADF有效降解率最高(P<0.05),苜蓿干草、玉米青贮和毛豆荚壳无显著差异(P>0.05)。综上所述,玉米芯和毛豆荚壳可作为非常规粗饲料资源加以开发利用。     

不同来源蛋白质饲料瘤胃降解特性研究

文章旨在研究豆粕、牡丹籽粕、棉籽粕、棕榈粕、啤酒糟、豆渣、味精渣、玉米酒精糟（DDGS）、芝麻饼粕和葵花饼共10种蛋白质饲料原料的瘤胃降解特性。试验选用3头装有永久性瘤胃瘘管的鲁西牛×利木赞杂交牛为试验动物,采用尼龙袋法测定10种蛋白质饲料的干物质（DM）、粗蛋白质（CP）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）瘤胃降解率。结果表明：味精渣DM有效降解率最高,芝麻饼粕最低,各原料间差异显著（P <0.05）;CP有效降解率为棉籽粕>牡丹籽粕>豆粕>味精渣>豆渣> DDGS>葵花粕>啤酒糟>棕榈粕>芝麻饼粕,各原料间显著差异（P <0.05）;味精渣、棉籽粕和豆粕的NDF有效降解率较高,棕榈粕、啤酒糟和芝麻饼粕较低,各原料间差异显著（P <0.05）;味精渣ADF有效降解率最高,其次为豆粕、棉籽粕和牡丹籽粕,均显著高于其他原料（P <0.05）。综上所述,不同来源蛋白质饲料具有不同的瘤胃降解特性,采用隶属函数进行综合营养评价,排序为味精渣>豆粕>棉籽粕> DDGS>牡丹籽粕>...     

构树不同部位与奶牛常用粗饲料瘤胃降解特性对比研究

本试验旨在研究构树不同部位(构树叶、构树枝叶、构树枝)与奶牛常用粗饲料(苜蓿干草、燕麦草)的瘤胃降解特性。选用3只装有永久性瘤胃瘘管的中国荷斯坦奶牛,采用尼龙袋法测定5种饲料的干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)瘤胃降解规律。结果表明:1)构树叶的CP含量显著高于苜蓿干草(P<0.05),NDF含量显著低于苜蓿干草(P<0.05);构树枝叶的CP含量与苜蓿干草差异不显著(P>0.05),NDF含量显著低于苜蓿干草(P<0.05);构树枝的CP含量与燕麦草差异不显著(P>0.05),NDF含量显著高于燕麦草(P<0.05)。2)5种饲料的DM有效降解率差异显著(P<0.05),由高到低依次为构树叶、构树枝叶、苜蓿干草、燕麦草和构树枝。5种饲料的CP有效降解率差异显著(P<0.05),由高到低依次为苜蓿干草、构树叶、构树枝叶、燕麦草和构树枝。构树叶的NDF有效降解率最高,显著高于其他4种饲料(P<0.05),其中构树枝叶与燕麦草差异不显著(P>0.05)。5种饲料的ADF有效降解率差异显著(P<0.05),由高到低依次为构树叶、燕麦草、苜蓿干草、构树枝叶和构树枝。综上所述,构树不同部位具有作为奶牛非常规饲料资源的潜力。     

不同淀粉源饲料的瘤胃降解特性研究初探

通过尼龙袋法测定了5种淀粉源饲料在瘤胃的降解率。结果显示,玉米和荞麦在瘤胃的有效降解率(60.0%和61.6%)低于燕麦、小麦和大麦(78.9%、75.4%、69.8%)(P<0.05);燕麦的可溶性淀粉含量比较高,大麦和小麦表现出在9h内已经达到大部分被降解。     

4种非常规饲料在肉牛瘤胃内降解特性的研究

试验旨在研究全株甘蔗青贮、木薯茎叶、香蕉茎叶青贮和白酒糟等4种非常规粗饲料在肉牛瘤胃中的降解特性。试验采用尼龙袋法,以3头装有永久瘘管的肉牛（云岭牛）为试验对象,每头牛做3个平行。4种非常规粗饲料通过瘤胃瘘管送至瘤胃腹囊中,分别在6、12、24、36、48、72 h取出,测定4种非常规粗饲料在不同时间点消化后的干物质（DM）、粗灰分（Ash）、粗蛋白质（CP）、中性洗涤纤维（NDF）、酸性洗涤纤维（ADF）、粗脂肪（EE）含量。结果显示：白酒糟的DM、CP含量显著高于其他3组（P<0.05）。香蕉茎叶青贮的Ash、NDF和ADF含量显著高于其他3种粗饲料（P<0.05）。木薯茎叶和白酒糟的EE含量均显著高于其他2种粗饲料（P<0.05）。DM、有机物（OM）、CP有效降解率均为白酒糟>全株甘蔗青贮>木薯茎叶>香蕉茎叶青贮。NDF有效降解率排序为香蕉茎叶青贮>木薯茎叶>白酒糟>全株甘蔗青贮。香蕉茎叶青贮和木薯茎叶的ADF有效降解率显著高于白酒糟和全株甘蔗青贮（P<0.05）。研究表明,4种粗饲料均表现出良好的饲喂效果,以白酒糟和...     

绵羊常用蛋白质饲料在瘤胃的降解特性

通过尼龙袋法测定了１０ 种蛋白质饲料在绵羊瘤胃内的干物质和蛋白质降解率。结果表明：在所测的１０ 种饲料中,豆粕、花生饼和苜蓿干草的干物质和蛋白质降解率最高,菜籽饼、棉籽饼、芝麻饼和胡麻饼居中,葵花饼、鱼粉和玉米蛋白粉的干物质和蛋白质降解率最低。饲料的蛋白质降解率（Ｙ） 与其干物质降解率（Ｘ）表现出密切相关：Ｙ＝ ０－８１Ｘ＋ １２ ．２５（ｒ＝ ０．８５ ,Ｐ＜ ０ ．０５） 根据降解特性,对降解率高的饼粕类应考虑进行理化保护以减少其在瘤胃内的降解     

生姜茎叶在肉羊瘤胃中的降解特性研究

本研究旨在分析生姜茎叶在肉羊瘤胃中降解特性,探索生姜茎叶在肉羊饲料中的应用潜力.以3只安装永久性瘤胃瘘管的肉羊为试验动物,采用尼龙袋法测定生姜茎叶主要营养成分在肉羊瘤胃内的降解率和降解参数.结果表明:生姜茎叶干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)在肉羊瘤胃中的降解率差异较大,D...     

瘤胃尼龙袋法测定常用饲料过瘤胃淀粉量及淀粉瘤胃降解率

以9头装有永久性瘤胃瘘管的内蒙古半细毛羯羊为试验动物,采用尼龙袋法对玉米淀粉、玉米、麸皮、豆粕、麻粕、棉籽粕、苜蓿干草、羊草、肋麦野豌豆、玉米秸等10种常用饲料的过瘤胃淀粉量及淀粉瘤胃降解率进行了比较研究。结果表明,各种饲料的过瘤胃淀粉量(g/kg)依次为417.85、404.84、226.31、62.04、110.56、108.61、73.50、50.87、47.55、24.43;其淀粉瘤胃降解率%依次为60.95、50.47、61.70、80.19、65.57、61.01、53.15、64.23、70.40、73.65。     

Signals for identifying cows at risk of subacute ruminal acidosis in dairy veterinary practice

Controlling rumen disorders is critical to ensure successful dairy herd health management. Lactation diets of dairy cows are commonly rich in concentrates and low in physically effective fibre. Feeding of these diets increases the risk of rumen disorders with far‐reaching consequences for cattle health, welfare and sustainability of dairy production. The term subacute ruminal acidosis or SARA is often used as a synonym for poor rumen health. Being subclinical, SARA lacks of clear symptoms and is therefore difficult to diagnose and to control in the practice. This review article summarises common and identifies new direct and indirect cow signals related to SARA. We have performed a scientific evaluation and interpretation of each of these cow signals by highlighting their advantages and disadvantages from the practitioner's point of view. The gold standard of SARA cow signals still remains direct measurement of ruminal pH. However, continuous pH monitoring is cost‐intensive and often biased by sensor drift. Single‐point ruminal pH measurements by oral stomach tubing or rumenocentesis have strong limitations. Therefore, there is a need for reliable and robust markers of SARA that are easily accessible and inexpensive. Such indirect parameters are the observation of chewing and feeding activities, as well as the monitoring of milk, faecal, urine and blood variables. Also, novel technologies that allow rapid and non‐invasive measurement of the rumen mucosa thickness and ruminal motility patterns might provide advantages in SARA diagnosis. Due to several constraints of these indirect diagnostic tools, such as limited specificity and sensitivity, we strongly recommend using a combination of the signals to reliably identify cows at risk of SARA in a dairy herd.     

Effects of Moringa oleifera silage on milk yield,nutrient digestibility and serum biochemical indexes of lactating dairy cows

This study investigated the effects of Moringa oleifera (MO) as a partial substitute of alfalfa hay on milk yield, nutrient apparent digestibility and serum biochemical indexes of dairy cows. MO was harvested at 120 days post‐seeding. Fresh MO was cut, mixed with chopped oat hay (425:575 on a DM basis), ensiled and stored for 60 days. Sixty healthy Holstein dairy cows were allocated to one of three groups: NM (no MO or control), LM (low MO; 25% alfalfa hay and 50% maize silage were replaced by MO silage) or HM (high MO; 50% alfalfa hay and 100% maize silage were replaced by MO silage). The feeding trial lasted 35 days. The LM and HM diets did not affect dry matter (DM) intake, milk yield or milk composition (lactose, milk fat, milk protein and somatic cell count). The apparent digestibility of DM and NDF was lower for HM group than NM group. Additionally, there were no significant differences in serum biochemical indexes between the LM and NM groups. The HM group had lower serum concentrations of total cholesterol, high‐density lipoprotein cholesterol, and low‐density lipoprotein cholesterol and higher serum concentrations of urea than the NM group. The partial replacement of alfalfa hay (≤50%) and maize silage with MO silage had no negative effects on milk yield, in vivo nutrient apparent digestibility or serum biochemical indexes of lactating cows.     

Effect of a non‐forage fiber of red bean hulls on ruminal mat characteristics,chewing activity and milk production in dairy cows

The evaluation of red bean hulls (RBH) as a non‐forage fiber source on ruminal mat formation, chewing activity and milk production was determined using two experiments. In experiment 1, four non‐lactating, rumen‐cannulated Holstein cows were offered a control diet of 60.1% forage, and an RBH diet of 51.6% forage and 9.4% RBH. Although the neutral detergent fiber (NDF) intake was higher with the RBH diet than the control diet, the physically effective NDF (peNDF) intake was lower. The rumination period tended to be longer with the RBH diet than with the control diet and the ruminal mat was formed even when the RBH diet was consumed. Ruminal fermentation parameters were not affected by treatment. In experiment 2, 40 lactating cows were fed a control diet of 53.4% forage or an RBH diet of 50.3% forage and 8.1% RBH. Dry matter intake, chewing activity and milk production were not affected by diet. Cows sorted against NDF in the control diet, but not in the RBH diet. It is concluded that normal ruminal function can be maintained because the ruminal mat was stratified and rumination activity was not reduced even when a low peNDF diet that contained RBH was given to dairy cows.     

壳聚糖在奶牛瘤胃中的降解率及其对瘤胃发酵的影响

试验旨在研究壳聚糖在奶牛瘤胃中的降解率及其对瘤胃发酵的影响。选择3头体况良好,年龄、体重、胎次、泌乳期相近,安装永久性瘤胃瘘管的荷斯坦泌乳牛作为供体牛。试验一采用尼龙袋法,分别在投入尼龙袋后2、4、8、12、24、36、72 h取样,测定壳聚糖在瘤胃内的实时降解率。试验二利用体外批次培养法,采用单因素完全随机试验设计依据壳聚糖在基础培养底物中的添加剂量分为6个处理组(0、0.02%、0.1%、0.5%、1%、2%)。其中,零剂量组为对照组,其余为壳聚糖组。分别于培养0、2、4、8、12、24 h时间点取样,研究不同添加水平的壳聚糖对奶牛瘤胃液体外发酵特性的影响。结果表明:壳聚糖在奶牛瘤胃内降解率很低,在72 h时的降解率仅有7.79%;添加不同水平的壳聚糖,对奶牛瘤胃体外发酵培养液的pH值、NH3-N浓度、菌体蛋白(BCP)含量、挥发性脂肪酸(VFA)含量、产气量均无显著的影响(P>0.05)。     

Herbage intake and ruminal digestion of dairy cows grazed on perennial ryegrass pasture either in the morning or evening

This study aimed to clarify diurnal fluctuations of herbage intake, ruminal fermentation of herbage carbohydrates and proteins, and digesta particulate weight in the rumen of grazing dairy cows. Six ruminally cannulated, non‐lactating dairy cows were grazed on perennial ryegrass/white clover pasture either in the morning (04.00 to 08.00 hours) or the evening (16.00 to 20.00 hours). Cows grazed in the evening spent more time (P < 0.01) and consumed more herbage (P < 0.01) compared with cows grazed in the morning. Higher (P < 0.05) daily mean concentrations of total volatile fatty acid, propionate and n‐butyrate in rumen fluid were observed for cows grazed in the evening compared with cows grazed in the morning. Although cows grazed in the evening ingested more crude protein compared with cows grazed in the morning, no significant difference in NH₃‐N concentration in rumen fluid was observed between them. The ratio of purine‐derivative concentration to creatinine concentrations was higher (P < 0.01) in the urine of cows grazed in the evening than in cows grazed in the morning. These results clearly indicated that evening grazing was advantageous for dairy cows compared with morning grazing, in terms of ruminal fermentable energy intake and nitrogen utilization efficiency.     

我国北方地区奶牛常用饲料蛋白质组分及其降解规律的研究

本试验研究以NRC(2001)奶牛营养需要(第7版)采用的对粗蛋白质组分的分析方法为基础,对奶牛养殖中常用的部分饲料原料进行取样分析,利用尼龙袋法测定出这些常用饲料原料的各种蛋白质组分(A、B、C)和B组分的降解速率。结果表明,粗饲料的粗蛋白质中A组分和C组分的比例较高,A组分变异较大;B组分的比例相对较小,在瘤胃中的降解速率较低。精料的粗蛋白质中B组分的含量较高,而C组分的含量较低。因而,精料是反刍动物瘤胃降解蛋白质(RDP)和瘤胃非降解蛋白质(RUP)的主要来源。     

Faecal characteristics and milk production of dairy cows in early-lactation fed diets differing in forage types in commercial herds

Effects of grass–clover silage (GCS) alone or combined with whole-crop cereal silage, maize silage (MS) or ensiled pressed sugar beet pulp (EPSB) on faecal characteristics and performance of early-lactation dairy cows were studied in 26 herds. Data were analysed with herd as the experimental unit and correlation coefficients among the variables were estimated. Feeding MS combined with GCS resulted in faeces of a firmer consistency (P?P?r?=?0.83, P?r?=??0.54, P?r?=?0.63, P?相似文献   

Follicular cysts in dairy cows

Follicular cysts are the most critical reproductive disorder in dairy cows and disturb the normal ovarian cycle, resulting in a prolonged interval from calving to conception. Therefore, this condition causes significant economic losses to the dairy industry. Two direct causal factors for cysts are suggested in this review; ovulation disorder and the delay of regression. Ovulation disorder has been accepted to be a main etiology of cystic follicle. This seems to be caused by the deficiency of positive feedback of estrogen to the hypothalamus, leading to the lack of luteinizing hormone surge. On the other hand, if a large anovulatory follicle is regressed immediately after the failure of ovulation, its follicle does not continue to grow, resulting in no cystic follicle being formed. Therefore, it is proposed that another cause of a cystic follicle is the delay (or absence) of the degeneration system of the follicle. This review will introduce these two causes separately, referring to recent advances in understanding the follicular cyst in dairy cows.