Chemistry of butter and butter making IV. The relationships among the cream acidity, the churning loss and the churning time

1. The influence of acidity, developed in cream that had been pasteurized while sweet and subsequently ripened, was studied over a pH range (in the buttermilk) from 4.5 to 7.0. 2. Three series of creams, viz., 20, 30 and 37.5 percent fat, were investigated. 3. The losses (calculated as percentage of the total fat) for all three series varied little in the pH range 7.0 to 5.5. In this region the least variation was encountered with 30 percent cream; such tendency in loss changes as was exhibited by 30 percent cream was toward a decreasing loss with decreasing pH, while the 37.5 percent cream losses tended to pass through a. minimum at pH 6.3 to 6.4. From pH 5.5 to pH 4.8 or 4.9 the losses rose to maxima (at 4.8 to 4.9) with 20 and 37.5 percent cream; a slight rise with no definite maximum at pH 4.8 to 4.9 occurred with 30 percent cream. With all three creams a marked change of function in the curves (loss vs. pH of buttermilk) occurred at pH 4.8 to 4.9; the loss dropped sharply and in practically linear fashion from that point to pH 4.5. 4. The above facts (especially the maximum at pH 4.8 to 4.9) were interpreted as indicating that casein plays an important role in the protection of the fat globules in cream, if the churning loss is taken as a measure of protective action. 5. The churning loss data correlated very well with electro-kinetic potentials of the fat globules, determined by Sommer and North and re-presented here. 6. Churning times show closer correlation with pH of buttermilk the lower the fat test of the cream. Other factors such as change in protein to fat ratio, increased viscosity, greater ease of whipping, lower specific gravity, etc., may be involved in affecting the churning times of the richer creams. 7. Churning time data in this and the third bulletin of this series indicate that, if the fat and serum in cream are in proper physical state and chemical equilibrium, no hard and fast rule can be drawn that long or short churning times must be associated with high losses. 8. Data show that the fat test of the buttermilk in low fat (18 to 20 percent), highly ripened creams (pH 4.5 to 4.6) is considerably lower than those for high fat (30 to 37.5 percent), sweet cream (pH 6.5). Calculated as the percentage of the total fat churned, however, the low fat, highly ripened cream losses are approximately equivalent to those for 30 percent sweet cream and are slightly higher than those for 37.5 percent sweet cream. This shows that the American, Australian and New Zealand churning losses compare very favorably with those obtained in Denmark, Germany and Holland. 9. Based on the data presented and others from the literature it was hypothecated that the protective action at the fat globule interface was caused by two types of protective materials- one labile and one non-labile. The latter is closely associated with the fat, presumably on the fat side of the interface, and consists of a protein-phospholipin complex. The former is oriented from the water side of the interface and is composed of all the surface tension lowering constituents of the serum. Of the serum constituents casein probably plays the most important protective role as indicated by certain dairy phenomena. 10. If the validity of the hypothesis presented is assumed, the following explanation of the churning process seems logical: Utilization of the labile protective materials, to stabilize foam interfaces, decreases their concentration at the fat-serum interface. When the labile to non-labile protective material ratio is sufficiently small that the fat globules are in an unstable state, they merge and lose their identity. This merger weakens the forces at the force centers of the fat globules to such an extent that the non-labile materials are released from the fat globule surfaces and are incorporated in the buttermilk, while the fat unites to form butter

A Survey of Dry Processed Corn Particle Size and Fecal Starch in Midwestern U.S. Feedlots

Optimizing grain processing practices in cattle feeding operations is critical to reaching maximum feed utilization efficiency. An increased degree of grain processing has consistently shown improved dry matter and starch digestibility; however, it exists with conflicting results on improving performance in finishing cattle. These inconsistencies are likely due to diet composition, such as roughage and co-product level, that could offset the effects of reduced particle size on rate of fermentation thus reducing the risk of digestive dysfunction. Finishing diets are commonly formulated with processed grain to increase utilization of starch and improve animal performance. Processing methods including steam-flaking, grinding, or dry-rolling improve total tract starch digestibility compared with that of whole grain. When dry-rolling corn for finishing cattle, recommendations often suggest that grain be coarsely processed, or cracked to prevent production of an excessive quantity of fine material that could potentially result in an increased rate of fermentation, reduced rumen pH, and digestive disturbances. However, previous research has reported that inclusion of dried distillers grains in finishing diets may influence optimal grain processing method. Grinding corn to a finer particle size when the grain is fed in combination with distillers grains may result in improved total tract starch utilization without causing reduced ruminal pH and digestive disturbances. The objective of this survey was to provide the feedlot industry with an indication of average particle size distribution from current manufacturing practices of dry processed corn, fecal starch content, and co-product and roughage inclusion levels in Midwestern feedlots

Effect of shade on animal welfare, growth performance, and carcass characteristics in large pens of beef cattle fed a beta agonist in a commercial feedlot

Citation: Hagenmaier, J. A., Reinhardt, C. D., Bartle, S. J., & Thomson, D. U. (2016). Effect of shade on animal welfare, growth performance, and carcass characteristics in large pens of beef cattle fed a beta agonist in a commercial feedlot. Journal of Animal Science, 94(12), 5064-5076. doi:10.2527/jas2016-0935Feedlot cattle (n = 1,395; BW = 568 +/- 43 kg) were used to evaluate the effects of shade on animal welfare, growth performance, and carcass quality during the summer of 2013 in a Kansas commercial feedlot. Seven lots of predominately black steers and heifers (4 and 3, respectively) visually determined to be approaching the final mo on feed were identified, randomly gate-sorted, and allocated to pens located across the feed alley from each other to receive 1 of 2 treatments: 1) Shade (mean shade area = 1.5 m(2)/animal) or 2) No shade. Shade was provided using a 13-ounce polyethylene fabric and pens were oriented northwest to southeast. The mean starting date was June 13 and the mean days on feed for lots while on the study was 38 d. Cattle were fed a 77.67% DM steam-flaked corn-based diet and had ad libitum access to water throughout the duration of the trial. Zilpaterol hydrochloride (ZIL) was included in the finishing ration at an inclusion rate of 8.3 mg/kg of DM for the last 20 d on feed with a 3 d withdrawal period. Pen floor temperatures (PFT) were measured using an infrared thermometer and prevalence of cattle open-mouth breathing (OMB) was recorded on a pen basis. In addition to shade treatment, the effect of temperature humidity index (THI) on PFT and OMB was analyzed by classifying days as either "Alert" (THI 79). On the day of slaughter, pens within a replicate were kept separate through all stages of the marketing channel from loading at the feedlot until stunning at the plant. Pen served as the experimental unit for all measurements. There was a THI x shade treatment interaction for PFT and OMB (P 0.05). Heat stress, a significant animal welfare concern and cause of reduced performance in feedlot cattle during the final phase of the feeding period, was alleviated in shaded cattle and illustrates the importance of shade provision as 1 tool to protect the welfare and increase feed consumption in large pens of feedlot cattle during hot summer months

Evaluating and modelling Hanabi-playing agents

Agent modelling involves considering how other agents will behave, in order to influence your own actions. In this paper, we explore the use of agent modelling in the hidden-information, collaborative card game Hanabi. We implement a number of rule-based agents, both from the literature and of our own devising, in addition to an Information Set-Monte Carlo Tree Search (IS-MCTS) agent. We observe poor results from IS-MCTS, so construct a new, predictor version that uses a model of the agents with which it is paired. We observe a significant improvement in game-playing strength from this agent in comparison to IS-MCTS, resulting from its consideration of what the other agents in a game would do. In addition, we create a flawed rule-based agent to highlight the predictor's capabilities with such an agent

Pathologies of acute interstitial pneumonia in feedlot cattle

Citation: Valles, J. A., Apley, M. D., Reinhardt, C. D., Bartle, S. J., & Thomson, D. U. (2016). Pathologies of acute interstitial pneumonia in feedlot cattle. American Journal of Animal and Veterinary Sciences, 11(1), 1-7. doi:10.3844/ajavsp.2016.1.7Acute Interstitial Pneumonia (AIP) is a costly issue that affects feedlot cattle. Research has yet to elucidate the etiology of AIP; therefore a case-control study was conducted to evaluate possible management and physiological factors that contribute to AIP in feedlot cattle. The experiment was conducted during the summer of 2011 in a commercial feedyard in Kansas. Animals exhibiting clinical signs of AIP and a control animal from the same pen were selected for ante-mortem examination. Post-mortem AIP cases were also selected for additional examination. Ante-mortem measurements included rumen gas cap hydrogen sulfide and pH, rectal temperature and body weight. Post-mortem examination added histological examination of lung tissue. Rectal temperature was greater in the AIP cattle (40.6±0.16°C) than controls (39.7±0.16°C; p0.10). Post-mortem rumen pH values were 6.3±0.4 and 5.7±0.6 for AIP and control cattle, respectively. Histological evaluation of lung samples showed that bronchiolitis was present in about 90% of the cattle affected with AIP. About 75% of the cattle with AIP also had bronchopneumonia. No relationships between feed intake patterns, or serum amylase or lipase levels were noted between treatments (p>0.20). This study generally confirms that AIP tends to occur more in heifers relative to steers, occurs in cattle at heavier weights or later in the feeding period and tends to be associated pathologically with bronchio’ litis and bronchopneumonia. The lack of differences in rumen measures and the feed intake data between AIP and control cattle suggest that feed intake patterns and rumen fermentation may not impact AIP in feedlot cattle and that it may be more directly related to bronchiolitis/bronchopneumonia due to chronic irritation or infection. © 2016 Jose A. Valles, Michael D. Apley, Chris D. Reinhardt, Steven J. Bartle and Daniel U. Thomson

Particle Size of Dry-rolled Corn Affects Starch Digestibility but Not Feedlot Performance

Dry-rolling corn is a common practice in feedlots located in the Midwestern and Northern Plains regions of the United States. Optimizing total digestive tract starch utilization in diets containing dry-rolled corn is essential for maximizing efficiency. However, recommendations often suggest that grain be coarsely cracked to avoid producing an excessive amount of fine material that could potentially increase the rate of fermentation, reduce rumen pH, and cause digestive disturbances. Wet distillers byproducts may be effectively used as a protein and energy source for feedlot finishing cattle and can replace a portion of the dry-rolled corn in the diet. The average geometric mean particle size of dry-rolled corn across all feedyards (n = 31) was 0.179 ± 0.035 in. with a range of 0.085 to 0.269 in. The objective of this study was to evaluate the effects of dry-rolled corn particle size on animal performance, carcass traits, and starch digestibility in feedlot finishing diets containing 20% wet distillers grains on a dry matter basis

The Determination of Paramagnetic Susceptibilities by High-resolution Nuclear Magnetic Resonance

Existing high-resolution NMR techniques for th e determinat ion of the magnetic susceptibilities of paramagne tic materials in solu tion are reviewed critically and the underlying theory is discussed. Attempts t o measure th e effect of interaction between indicator protons and para m agnetic ions suggest that, in the cases examined, this is less imp orta nt than the change in field or frequency con sequent on the insertion of paramagnetic material in the probe of a field/frequency locked spectrometer. Several variants of the substitution method have been tested. Provid ed that the calibration factor appropriate to the combination of tube and probe has b een d e termined, a simple substitution method i s practicable but, on the whole, the internal/external ·reference method with spinning concentric cylindrical samples is to be preferred

Flake Density, Roll Diameter, and Flake Moisture All Influence Starch Availability of Steam-Flaked Corn

Steam-flaked corn is commonly fed in feedlot finishing diets because steam-flaking improves starch availability and nutrient utilization, thus improving the overall feeding value of corn. In most operations which utilize steam-flaked corn, grain is processed to a pre-determined flake density by setting the rolls to a specific separation distance and using tension to hold rolls together. Flaked grain is most often produced to a bulk density between 24 and 32 lb/bu, with a common recommendation of 27 lb/bu for corn; however, flake density among steam-flakers within a single mill and among feedlots can vary greatly. Flaking to a similar density using 2 flakers does not ensure similar starch availability. The degree of starch gelatinization or starch availability of steam-flaked corn can be estimated using analytical procedures such as enzymatic hydrolysis, gas production, and steam-flaked corn gelatinization methods. Routinely evaluating starch availability is used as a quality control method to standardize the steam-flaking process to ensure within-day and day-to-day manufacturing consistency. The concentration of readily available starch in steam-flaked corn is indicative of the rate of starch fermentation in the rumen. When starch is too readily available and is fermented at an excessively rapid rate, acid can accumulate in the rumen, reducing ruminal pH, and ultimately resulting in increased prevalence of digestive disturbances. Factors that contribute to variation between feedlot operations with respect to steamflaked corn quality include type and dimensions of flaking equipment, grain type, grain variety and moisture content, roll wear, and steam-flaking procedures. Sampling and handling procedures contribute to precision of results; therefore, sampling procedures need special attention, and consistency must be evaluated when attempting to determine starch availability of steam-flaked corn. The objective of this study was to evaluate starch availability of steam-flaked corn comparing roll dimensions and steam-flaked corn flake densities among flaking systems and feedyards and to provide information on the equipment utilized, steam-flaked corn flaking procedures, and to define current manufacturing practices of steam-flaking in commercial feedlot operations

Survey of Cattle Feedlot Facilities in the High Plains Region of the United States

Defining the appropriate dimensions and type of feeding facilities for feedlot cattle fed in outdoor pens is important because the characteristics of these facilities have a significant impact on the performance, welfare, and health of cattle housed in those facilities, as well as a considerable impact on the final cost of the project. Although multiple sources can be found in the literature that provide recommendations with regard to design of facilities to be used in outdoor feeding facilities for feedlot cattle, there are no published data that describe the dimensions and type of feeding facilities currently used by the feedlot industry in outdoor feeding operations. Thus, the objective of this survey was to obtain descriptive data regarding outdoor cattle feeding facilities currently used by feedlots in the High Plains region of the United States