Phase Feeding of Urea after Feeding Soybean Meal to Dairy Cows

Urea-free control, medium-, and high-urea concentrates containing 0, 1.6, and 2.3% urea, respectively, were applied as main treatments, each to a group of nine lactating cows during three 8-wk periods. Split plot treatments consisted of feeding each concentrate normally or the urea portion in phase 2 or 4 h after feeding the soybean meal component. Dry matter intake, milk yield, milk lipid composition of butyric through capric acids were decreased, but milk linoleic acid was increased with high-urea rather than medium-urea or control concentrate. Ammonia in blood serum was reduced with 2-h phase feeding and urea was reduced with 2- or 4-h phase feeding as compared to normal feeding. Ammonia was unaffected by normal or phase feeding of the control concentrate. Normal feeding of high-urea concentrate increased ammonia in serum, but phase feeding reverted concentration comparable to the control group (160 to 122 μ/100 ml). Ammonia was nearly the same with normal or phase feeding of medium-urea concentrate.     

Effect of Masonex and Forms of Cottonseed Hulls on Dairy Cows

Thirty-six lactating Holstein cows were in a 5 × 3 factorial partially balanced incomplete block design with three missing categories to study effects of different forms of cottonseed hulls and liquid supplements on milk production and composition. Roughages were regular cottonseed hulls, pelleted cottonseed hulls, pelleted cottonseed hulls with 9% fat, pelleted undelinted cottonseed hulls, and pelleted undelinted cottonseed hulls with 9% fat. Liquid supplements were 8% Masonex² (hemicellulose extract) and 8% cane molasses. Control had no supplement. All rations were adjusted to contain 30% cottonseed hulls. Roughages with added fat gave total rations of 2.5% added fat (air dry).Least square means for daily intake of dry matter, milk yield, and fat percent were regular cottonseed hulls 21.6 kg, 20.3 kg, 3.37%; pelleted cottonseed hulls 20.3 kg, 21.4 kg, 3.06%; pelleted cottonseed hulls plus fat 20.1 kg, 21.2 kg, 2.51%; pelleted undelinted cottonseed plus fat 19.4 kg, 20.9 kg, 2.73%. Pelleted cottonseed hulls increased milk yield, decreased dry matter intake and milk fat percent, but did not affect milk fat yields. Rations with pelleted undelinted cottonseed hulls resulted in higher milk fat percent and body weight than pelleted cottonseed hulls. Added fat decreased milk fat percent and yield because of high degree of unsaturation. Liquid treatments produced no detectable effects on dry matter intake, milk yield, or fat percent.     

Protected Methionine and Heat-Treated Soybean Meal for High Producing Dairy Cows

Twenty-four high producing Holstein cows (14 primiparous and 10 multiparous) were fed concentrate mix containing heat-treated soybean meal without or with 15 g of added DL-methionine daily provided as 50 g of ruminally protected methionine product during wk 4 through 16 postpartum. The 15% crude protein mixed diets contained 30% (dry matter basis) corn silage, 15% alfalfa hay, and 55% concentrate mix. Covariant adjusted yields of milk (34.6 and 33.1 kg/d), 4% fat-corrected milk (28.4 and 27.6 kg/d), and solids-corrected milk (29.0 and 28.5 kg/d) were not increased by feeding supplemental methionine. Percentages of fat (2.81 and 2.92) and protein (2.88 and 2.92) were similar, whereas total solids (11.49 and 12.69) and solids-not-fat (8.68 and 8.77) were higher with supplemental methionine. Dry matter intakes (20.2 and 21.0 kg/d) were higher when cows were fed supplemental methionine. Ruminal pH, volatile fatty acids, and ammonia as well as blood serum urea and glucose were generally unaffected by methionine supplementation. Concentrations of methionine in arterial and venous plasma were elevated slightly when additional methionine was fed. The first-limiting amino acid for milk production, methionine, was calculated by several methods and was not changed by feeding supplemental ruminally protected methionine.     

Soybean Hulls as an Iron Source for Bread Enrichment

Soybean hulls, a concentrated source of iron, may have potential as a source of iron fortification in baked products. Retention of ⁵⁹Fe in rats from white bread containing intrinsically labeled soybean hulls did not differ significantly (p<0.05) from extrinsically labeled white bread fortified with bakery grade ferrous sulfate (70.4 and 63.1%, respectively). Physical and sensory evaluations of bread containing up to 5% soybean hulls did not differ from white bread in loaf volume, cross-sectional area, tenderness or overall acceptance. These results suggest that soybean hulls are a good source of available iron and may be added to bakery products without deleterious effects in baking performance and sensory acceptability.     

大豆分离蛋白在乳制品中的应用

阐述了大豆分离蛋白在乳制品中应用的可行性,介绍了大豆分离蛋白在奶粉、酸奶、冰淇淋、液态奶和乳饮料等产品中应用的现状,提出大豆分离蛋白在奶粉中添加可以与糖混合加入,添加量为1%～5%,同时介绍了分离蛋白在其他乳制品中的应用方法,目前国内外有一些大豆分离蛋白的相关报道,但总体上分离蛋白产品还不够成熟,需要进一步的完善。     

Cubed Complete Rations for Lactating Dairy Cows

Production by cows fed cubed complete rations as compared to the same ration components fed separately as long hay and concentrate was determined in two experiments. The cubed rations reduced milk fat percentages in both experiments and total fat production in one experiment. Solids-not-fat was increased slightly by cubed rations. Lower efficiency of feed utilization for the production of 4% fat-corrected milk was evident for cows fed cubed rations. Losses of body weight following parturition were reduced, and subsequent weight recoveries were more rapid in cows fed cubed rations. Also, molar ratios of acetic/propionic acids in the rumen were reduced. Effects of rations on milk composition, changes in body weight, and ratios of volatile fatty acids appear to be related to differences in coarseness or texture of the roughage components of cubed and baled hay rations. The results of these feeding experiments indicate complete rations prepared by cubing chopped alfalfa hay and concentrates in conventional hay cubing equipment have limitations as the sole rations for high producing dairy cows.     

Effects of Body Condition and Protein on Milk Fat Depression in Early Lactation Dairy Cows

Twenty multiparous and 16 primiparous Holstein cows were fed either a high energy or low energy diet during the dry period to achieve different degrees of body condition. Three weeks postpartum, cows were randomly assigned to either a high protein (23% CP) or a low protein (14.5% CP) diet. The diet contained 21% ADF during wk 3 through 6 postpartum and lowered to 9% ADF during wk 7 through 14 postpartum to depress fat test. Cows fed the low energy prepartum diet had less fat depression when fed the high protein postpartum diet compared with the low protein diet. Milk fat depression was more severe for all cows fed the high energy prepartum diet. Depression in milk fat percentage for multiparous cows was 30.8, 10.2, 34.5, and 26.0% for high energy-high protein, low energy-high protein, high energy-low protein, and low energy-low protein groups, respectively. For primiparous cows, milk fat depression was 37.3, 24.1, 37.0, and 34.6%. After the fiber change, depression in acetate to propionate ratio was less for multiparous cows fed high protein than for those fed low protein. Prepartum energy did not influence acetate to propionate ratio depression that resulted from the fiber change.     

By-Product Feeds for Lactating Dairy Cows: Effects of Cottonseed Hulls,Sunflower Hulls,Corrugated Paper,Peanut Hulls,Sugarcane Bagasse,and Whole Cottonseed with Additives of Fat,Sodium Bicarbonate,and Aspergillus oryzae Product on Milk Production

In Experiment 1, Holstein cows (32) fed diets in three 28-day periods were used to evaluate a 3 × 2 × 2 factorial arrangement of fiber sources (sunflower hulls, pelleted cottonseed hulls, and pelleted undelinted cottonseed hulls at 35% of dry matter), fat (0 or 2.5%). and sodium bicarbonate (0 or 1.0%). Sixteen cows also received Aspergillus oryzae product (56.7 g/day) continuously. Sunflower hulls decreased daily intake (19.4 versus 25.1 kg), milk (23.3 versus 26.5 kg), milk protein (2.85 versus 2.95%), and body weight change (?.08 versus .90 kg), but milk fat percent was higher (3.54 versus 3.32%). Sunflower hulls depressed digestibility of dry matter, organic matter, and acid detergent fiber. Added fat reduced milk fat and protein percents. Experiment 2 evaluated fiber sources (20% ground corrugated cardboard boxes, combination of 10% cardboard and 10% peanut hulls, or 30% cottonseed hulls), animal fat (0 or 2.5%), sodium bicarbonate (0 or .75%), and condensed molasses solubles by-product from rum distilling (0 or 10%). Corrugated boxes effected lowest intake (18.0 kg/day), cottonseed hulls highest intake (23.5 kg/day), and combination intermediate (20.2 kg/day). Added fat depressed fat percent. Condensed molasses solubles lowered milk yield but increased milk fat percent (3.76 versus 3.30), molar percent of acetic acid, and ratio of acetic to propionic. In two other experiments whole cottonseed (12.5 or 15% of dry matter) with corn silage, pelleted steam pressure treated sugarcane bagasse, or cottonseed hulls increased milk yield but decreased milk fat percent, especially with pelleted bagasse.     

A Naturally Occurring Mineral as a Buffer in the Diet of Lactating Dairy Cows

In Experiment 1, 24 cows were used to compare the acceptance of concentrate mixtures containing 1) no buffer, 2) 1.5% sodium bicarbonate, or 3) 1.5% Alkaten (a naturally occurring mineral containing primarily sodium carbonate and sodium bicarbonate). During the 1st wk the cows fed Alkaten had sharply reduced concentrate intakes. By the 3rd wk, concentrate intakes were nearly equal among groups. Total feed consumption was equal by the 2nd wk because cows compensated by eating more forage.In Experiment 2, 27 cows were assigned at 1 d postpartum for 7 wk to one of three complete rations of 15% whole cottonseed, 30% corn silage, and 55% concentrate with buffers as in Experiment 1. Feed intakes of 3.04, 3.08, and 3.31 kg/100 kg of body weight, respectively, were not different for the 7 wk, but cows fed Alkaten ate more feed wk 4 through 7. There was no depression in feed intake in wk 1, suggesting that blending the concentrate with forage resolved the initial depression seen in Experiment 1.Rumen pH, rumen volatile fatty acid molar percentages and ratios, and urine pH means suggest that Alkaten is similar to sodium bicarbonate in buffering or neutralizing action.     

以水解大豆蛋白为主要壁材的β-胡萝卜素微胶囊化

水解大豆蛋白分别与糊精（ＳＰＨ＋ＭＤ）以及蔗糖（ＳＰＨ＋Ｓ）复配为壁材微胶囊化β－胡萝卜素，研究结果表明，ＳＨＰ＋Ｓ壁材体系的微胶囊化产品的效率明显优于ＳＰＨ＋ＭＤ壁材体系产品，产率无显著差异。相应的较优工艺参数为：壁材中蛋白质与蔗糖比例为６∶１４，体系壁材浓度２０％，黄原胶浓度０．５％，乳化时均质压力４０Ｍｐａ（乳化温度７０℃），喷雾干燥进风温度１９５℃（出风温度８０～９０℃）。     

Alfalfa Silage or Hay Versus Corn Silage as the Sole Forage for Lactating Dairy Cows

In Trial 1, three rations were fed to 21 cows in a 3 × 3 Latin square: 60% alfalfa silage, 60% corn silage, and 79% corn silage (dry matter basis) with the balance from corn and soybean meal. Acid detergent fiber measures indicated alfalfa and corn silage were of excellent quality. Milk production was similar on 60% forage rations but lower on 79% corn silage. Milk fat was reduced on 60% corn silage. In Trial 2, four rations were fed to 16 cows in a 4 × 4 Latin square: 63% alfalfa silage, 60% alfalfa hay, 60% corn silage, and 76% corn silage. Alfalfa forages were higher in acid detergent fiber but corn silage was similar to Trial 1. Dry matter digestibility was highest on 60% corn silage, intermediate on 63% alfalfa silage and 76% corn silage, and lowest on 60% alfalfa hay. Milk production was similar on the diets containing 60 and 63% forage and lower on 76% corn silage. Milk protein concentration was reduced on the alfalfa diets. Highest protein secretion and feed conversion was supported by 60% corn silage. In both trials, potentially digestible neutral detergent fiber from alfalfa was more digestible than that from corn silage, and concentrations of urea in milk and blood were highly correlated. Results indicate high quality alfalfa silage is comparable to corn silage for milk production.     

Development of a One-Piece Reentrant Cannula for the Proximal Duodenum of Dairy Cows

A one-piece cannula was developed for reentry or spot collection of duodenal digesta in dairy cows. Progession through three cannula designs is described. Exteriorizing cannulae between the tenth and eleventh ribs produced stable preparations although ribs were deformed. A simple one-piece T cannula was suitable for spot sampling, but digesta blockage prevented its use for reentry collections. A double entry T cannula was unsuitable for reentry collections because of digesta blockages and inability to secure diversion gates in the cannula. A Y-shaped cannula allowed blockage-free reentry collections and easy spot sampling. Diversion gate design provided for a snug fit, and dualphase digesta marker recovery studies and necropsy findings suggested complete diversion in two of three cows. Post-mortem observations of rib distortion and intestinal tissue erosion from between the cannula and abdominal wall suggest inclusion of an inner restraining collar for future preparations. Several other modifications are discussed.     

Relative Efficiency of Selection Methods for Profit in Dairy Cows

Selection singly on milk yield and calculated profitability traits, selection indexes, and regression indexes were compared for the relative gains in expected profit to 72 mo of age or life time profit. Indexes consisted of five traits of the first lactation: milk, fat percent, days in milk, number of breedings, and age at first calving. The study was on 1806 Holstein cows sired by 404 bulls in 38 California herds. Genetic gain in total profit was 13 to 14% greater when selection was on estimated profit to 41 mo than on milk yield to 305 days in the first lactation. Selection on traits of estimated profit on three bases, to 305 days in first lactation, to end of first lactation, and to 41 mo of age was 2 to 14% more efficient for genetic gain in total profit than selection on corresponding traits of milk yield or selection indexes. Regression indexes were 3 to 19% more efficient than selection indexes for predicting subsequent cumulative profit. In contrast, selection indexes were 6 to 20% more efficient than regression indexes for genetic gain in total profit. Heritabilities for estimated profit and traits of milk yield in the first lactation ranged from .26 to .49 for cows with two or more calvings. Heritabilities for profit to end of first lactation and to 41 mo of age exceeded comparable milk yield traits by 15 to 27%. The economic value of a 1-mo decrease in age at first calving was equivalent to an increase of 138 kg milk yield to the end of the first lactation for gain in total profit to 72 mo of age. Similarly, the genetic effects, or relative selection value, of a 1-mo decrease in age at first calving is valued at approximately 471 kg milk.     

Addition of Soluble Soybean Polysaccharides to Dairy Products as a Source of Dietary Fiber

Abstract: Increasing consumption of dietary fiber in food leads to many important health benefits: for example, reduction in blood cholesterol, reduced risk of diabetes, and improved laxation. Water soluble soybean polysaccharide (SSPS) is a dietary fiber extracted and refined from okara, a byproduct of soy manufacturing. It was incorporated into 3 categories of dairy-based products, thickened milkshake-style beverages, puddings, and low-fat ice cream, to the maximum amount without over-texturing the food. Rheological measurements and sensory tests were used to develop desirable SSPS-fortified products. From the rheological data, 4% SSPS-fortified dairy beverages and 4% SSPS -fortified puddings were in the range of commercial products. From sensory analyses, 4% SSPS-fortified dairy beverage with 0.015%κ−carrageenan, 4% SSPS-fortified pudding with 0.1%κ−carrageenan, and 2% SSPS-fortified low-fat ice cream gained the highest scores in consumer hedonic rating. Panelists also indicated their willingness to consume those products if they were available commercially. Practical Application: Since the dietary fiber intake of many people is below their suggested adequate intake values, strategies to successfully fortify foods with fiber may help alleviate this gap. We have developed 3 dairy products, a beverage, a pudding, and a low-fat ice cream, that have been fortified with soluble soybean polysaccharide at levels of 4%, 4%, and 2%, respectively. These products were within acceptable ranges of rheological parameters and other physical stability measurements and were judged to be acceptable by sensory analyses.     

Palatability of Methionine Hydroxy Analog or DL-Methionine for Lactating Dairy Cows

A decrease in grain intake occurred initially after feeding supplemental methionine hydroxy analog (top-dressed or mixed with concentrate) but top-dressing DL-methionine did not affect intakes. After initial adjustment (1 to 3 d), cows generally returned to normal grain intakes on diets supplemented with methionine hydroxy analog. Intake patterns were similar at all methionine hydroxy analog levels, which attained three to four times that recommended for supplementation. Increases in plasma free methionine at methionine hydroxy analog intakes above 40 g/d suggest bypass of additive for intestinal absorption.     

A Blend of Essential Plant Oils Used as an Additive to Alter Silage Fermentation or Used as a Feed Additive for Lactating Dairy Cows

A blend of essential plant oils was evaluated for its effects on silage fermentation and animal performance. In the first experiment, the blend of essential oils was mixed with freshly chopped whole-plant corn to achieve a concentration of 0, 40, or 80 mg of active product per kilogram of fresh forage weight. Whole-plant corn was also mixed with a buffered propionic acid-based product at 0.2% of fresh forage weight. The blend of essential oils did not affect the populations of yeasts, molds, lactic acid bacteria, or enterobacteria; the fermentation end products; or the aerobic stability of the corn silage. Addition of the buffered propionic acid additive moderately reduced the production of acids during fermentation and resulted in a small reduction in the numbers of yeasts after ensiling, but did not affect aerobic stability. In a second experiment, 30 Holstein cows (4 primiparous and 26 multiparous) averaging 118 ± 70 d in milk and producing 38 ± 16 kg of milk/d were fed a total mixed ration, once daily, that consisted of (on a DM basis) 25% corn silage, 15% alfalfa silage, 10% alfalfa hay, and 50% concentrate. One-half of the cows were fed a blend of essential oils that was mixed directly into their total mixed ration to provide 1.2 g/cow per d for 9 wk. Cows fed the essential oils ate 1.9 kg more dry matter/d and produced 2.7 kg more 3.5% fat-corrected milk/d than did cows fed the control diet. The percentages of milk fat and protein, the somatic cell count numbers, and the concentrations of milk urea nitrogen were unaffected by treatment. Feed efficiency, change in body weight, and change in body condition scoring were also similar between treatments. After 12 h of incubation, the addition of a moderate dose and a high dose of essential oils to in vitro ruminal fermentations had no effect on the concentration of total VFA compared with the control treatment. However, they decreased the molar proportions of acetic, butyric, and valeric acids and increased the proportion of propionic acid. The blend of essential oils evaluated in this study altered in vitro ruminal fermentation and improved animal performance when fed directly to cows, but it did not affect the fermentation or aerobic stability of corn silage.