Journal of Dairy Science back issues from January 2006:
Invited Review: Methods to Determine Body Fat Reserves in the Dairy Cow with Special Regard to Ultrasonographic Measurement of Backfat Thickness
Jan 01, 2006; ... ABSTRACT As the dairy cow uses body energy reserves in early lactation, body condition scoring has become an integral part of dairy herd management. Several methods based on visual and tactile evaluation have been developed. Problems caused by the subjectivity of these techniques have ...
Effect of Trisodium Citrate Concentration and Cooking Time on the Physicochemical Properties of Pasteurized Process Cheese
Jan 01, 2006; ... ABSTRACT The effects of the concentration of trisodium citrate (TSC) emulsifying salt (0.25 to 2.75%) and holding time (O to 20 min) on the textural, rheological, and microstructural properties of pasteurized process Cheddar cheese were studied using a central composite rotatable design ....
Proteolysis and Microstructure of Piacentinu Ennese Cheese Made Using Different Farm Technologies1
Jan 01, 2006; ... ABSTRACT The aim of this study was to provide the biochemical and structural characterization of Piacentinu Ennese cheese and to evaluate the impact of different farm technologies on cheese proteolysis and microstructure. Fifteen cheeses were manufactured according to traditional ...
Use of the Foodtexture Puff Device to Monitor Milk Coagulation
Jan 01, 2006; ... ABSTRACT The further automation of cheese-making on an industrial level requires the development of sensor devices to monitor the gelation process and especially the firming phase. In this paper, the Foodtexture Puff Device (FPD) is tested for its ability to monitor the gelation process ...
Ice Recrystallization Inhibition in Ice Cream as Affected by Ice Structuring Proteins from Winter Wheat Grass
Jan 01, 2006; ... ABSTRACT Ice recrystallization in quiescently frozen sucrose solutions that contained some of the ingredients commonly found in ice cream and in ice cream manufactured under commercial conditions, with or without ice structuring proteins (ISP) from cold-acclimated winter wheat grass ...
Fluorescent Labeling Study of Plasminogen Concentration and Location in Simulated Bovine Milk Systems
Jan 01, 2006; ... ABSTRACT A fluorescent labeling method was developed to study plasminogen (PG) concentration and location in simulated bovine milk. Activity and stability of PG labeled with Alexa Fluor 594 (PG-594) were comparable to those of native PG. The fluorescent signal of PG-594 exhibited pH, ...
Indirect Chiral HPLC Determination and Fluorimetric Detection of D-Amino Acids in Milk and Oyster Samples
Jan 01, 2006; ... ABSTRACT The indirect chiral method, based on the o-phthaldialdehyde reaction using the chiral N-acetyl-L-cysteine reagent, has been optimized to determine o-amino acids in milk and oyster samples. Both the derivatization reaction and the HPLC separation have been improved, and simple ...
Technical Note: Improved Extraction Method with Hexane for Gas Chromatographic Analysis of Conjugated Linoleic Acids
Jan 01, 2006; ... ABSTRACT Extraction properties of different solvents (chloroform/methanol, hexane/isopropanol, and hexane) were studied for the gas chromatographic analysis of conjugated linoleic acids (CLA) from probiotic bacteria grown in de Man, Rogosa, and Sharpe medium. As compared with ...
Stocking Density and Feed Barrier Design Affect the Feeding and Social Behavior of Dairy Cattle
Jan 01, 2006; ... ABSTRACT The objectives of this study were to: 1) evaluate how stocking density at the feed bunk affects feeding and social behavior of dairy cows; and 2) determine if this effect is further influenced by the type of feed barrier used. Thirty-six lactating Holstein cows, allotted to 4 ...
Properties of Whey Protein Isolates Extruded under Acidic and Alkaline Conditions1
Jan 01, 2006; ... ABSTRACT Whey proteins have wide acceptance and use in many products due to their beneficial nutritional properties. To further increase the amount of whey protein isolates (WPI) that may be added to products such as extruded snacks and meats, texturization of WPI is necessary ....
Improvement of Texture and Structure of Reduced-Fat Cheddar Cheese by Exopolysaccharide-Producing Lactococci
Jan 01, 2006; ... ABSTRACT The objective of this study was to evaluate the effect of capsular and ropy exopolysaccharide (EPS)-producing strains of Lactococcus lactis ssp. cremoris on textural and microstructural attributes during ripening of 50%-reduced-fat Cheddar cheese. Cheeses were manufactured with ...
Effects of Feeding Propionibacteria to Dairy Cows on Milk Yield, Milk Components, and Reproduction1
Jan 01, 2006; ... ABSTRACT Two weeks before parturition, 38 Holstein primiparous and multiparous cows were assigned to 1 of 3 treatment groups: control animals (n = 13) received regular total mixed rations (TMR), the low-dose group (n = 14) received the control TMR plus 6 × 10^sup 10^ cfu/cow of ...
Effect of Hoof Pathologies on Subjective Assessments of Dairy Cow Gait
Jan 01, 2006; ... ABSTRACT To explore how hoof pathologies affect dairy cattle gait, we studied cows with sole hemorrhages (n = 14), sole ulcers (n = 7), and those with no visible injuries (n = 17). Overall gait assessments, scored from video using a 1 to 5 numerical rating system (1 = sound, 5 = severely ...
Short Communication: Feed Bunk Utilization in Dairy Cows Housed in Pens with Either Two or Three Rows of Free Stalls1
Jan 01, 2006; ... ABSTRACT The goal of this observational study was to determine whether there were significant differences in feed bunk utilization patterns of dairy cows in free-stall pens with either 2 or 3 rows of stalls. Previously recorded 24-h videos of the high-yielding, mature cow group in 5 ...
Slatted Floors and Solid Floors: Stress and Strain on the Bovine Hoof Capsule Analyzed in Finite Element Analysis
Jan 01, 2006; ... ABSTRACT An established finite element model of a bovine claw was used to compare mechanical stress levels in a loaded model claw on different types of flooring. The following situations were compared: a claw standing on a solid floor, a claw standing on the edge of a short tie stand, ...
Short Communication: The Nature of Heptadecenoic Acid in Ruminant Fats
Jan 01, 2006; ... ABSTRACT Heptadecenoic acid (17:1) is a minor constituent of ruminant fats and its isomeric definition remains undefined in most reports on ruminant milk and intramuscular fat. Samples of milk and intramuscular fat of bovine, ovine, and caprine origin were analyzed by gas chromatography ...
In Vitro Effects of Nonesterified Fatty Acids on Bovine Neutrophils Oxidative Burst and Viability1
Jan 01, 2006; ... ABSTRACT An in vitro study was conducted to examine the influence of nonesterified fatty acids (NEFA) on bovine polymorphonuclear leukocytes (PMN). Eight healthy, midlactating Holstein cows were used as blood donors. Blood PMN were isolated and incubated with a mixture of NEFA, ...
Technical Note: Improved Method for Rapid DNA Extraction of Mastitis Pathogens Directly from Milk
Jan 01, 2006; ... ABSTRACT Efficient control against bovine mastitis requires sensitive, rapid, and specific tests to detect and identify the main bacteria that cause heavy losses to the dairy industry. Molecular detection of pathogenic microorganisms is based on DNA amplification of the target pathogen ....
Lipid Metabolite Profiles and Milk Production for Holstein and Jersey Cows Fed Rumen-Protected Choline During the Periparturient Period1
Jan 01, 2006; ... ABSTRACT Choline is important for assembly of very low density lipoproteins to export triglyceride from liver; however, studies to assess the effect of rumen-protected choline (RPC) supplementation on blood lipid metabolites in periparturient dairy cows have not been conducted ....
Effects of Additional Milk Replacer Feeding on Calf Health, Growth, and Selected Blood Metabolites in Calves
Jan 01, 2006; ... ABSTRACT The objective of the experiment was to evaluate effects of increased milk replacer feeding on growth, intake, feed efficiency, and health parameters in stressed calves. Holstein bull calves (n = 120; approximately 3 to 8 d of age) were purchased from sale barns and dairy farms ...
Effects of Mixing on Drinking and Competitive Behavior of Dairy Calves
Jan 01, 2006; ... ABSTRACT Group housing provides increased access to space and social interactions for calves while reducing labor costs for producers. However, group housing necessarily requires that calves be mixed and no research to date has addressed the effects of mixing on behavior of milk-fed ...
Computer-Controlled Milk Feeding of Group-Housed Calves: The Effect of Milk Allowance and Weaning Type
Jan 01, 2006; ... ABSTRACT Calves fed by computer-controlled milk feeders are often weaned gradually by reducing the size of the milk portions. However, reducing the number of milk portions instead may lower calves' occupation of the milk feeder and stimulate their concentrate intake, especially when they ...
Dietary Forage and Nonfiber Carbohydrate Contents Influence B-Vitamin Intake, Duodenal Flow, and Apparent Ruminal Synthesis in Lactating Dairy Cows
Jan 01, 2006; ... ABSTRACT The objective of this experiment was to quantify intakes, duodenal flows, and ruminal apparent synthesis (AS) of B-vitamins in lactating dairy cows fed diets varying in forage and nonfiber carbohydrate (NFC) contents. Eight (4 primiparous and 4 multiparous) ruminally and ...
Milk Production of Dairy Cows Fed Differing Concentrations of Rumen-Degraded Protein1
Jan 01, 2006; ... ABSTRACT Thirty-two multiparous and 16 primiparous Holstein cows in midlactation averaging 126 d in milk were used to determine the effects of rumen-degraded protein (RDP) concentration on lactation performance. Cows were assigned to diets in a repeated Latin square design with 3-wk ...
Feeding Lactose to Increase Ruminal Butyrate and the Metabolic Status of Transition Dairy Cows1
Jan 01, 2006; ... ABSTRACT Twenty-four multiparous Holstein cows (775 ± 24 kg body weight; 3.4 ± 0.11 body condition score) were used in a randomized complete block design experiment to determine the impact of increased ruminal butyrate from the fermentation of lactose on metabolism and lactation. Dietary ...
Milk from Forage as Affected by Carbohydrate Source and Degradability with Alfalfa Silage-Based Diets
Jan 01, 2006; ... ABSTRACT Milk from forage (MF) is an estimation of the milk produced solely from forage intake. It is calculated by subtracting milk production theoretically allowed by concentrates from total milk production, assuming that maintenance requirements are covered by the forage portion of ...
Effects of Physically Effective Fiber on Chewing Activity and Ruminal pH of Dairy Cows Fed Diets Based on Barley Silage1
Jan 01, 2006; ... ABSTRACT The objective of this study was to investigate the effects of physically effective neutral detergent fiber (peNDF) content of dairy cow diets containing barley silage as the sole forage source on feed intake, chewing activity, and ruminai pH. The experiment was designed as a ...
Milk and Cheese from Cows Fed Calcium Salts of Palm and Fish Oil Alone or in Combination with Soybean Products1
Jan 01, 2006; ... ABSTRACT Twenty cows were used in a randomized block design experiment for 6 wk to determine the influence of feeding partial ruminally inert Ca salts of palm and fish oil (Ca-PFO), alone or in combination with extruded full-fat soybeans or soybean oil, on milk fatty acid (FA) methyl ...
Effects of Inbreeding in the Dam on Dystocia and Stillbirths in US Holsteins
Jan 01, 2006; ... ABSTRACT Dystocia scores were recorded by producers on 120,434 Holsteins (218,213 records) from 1985 through 1996; dystocia scores 3 to 5 were coded as difficult births. Stillbirths were recorded for deaths within the first 48 h after birth. Data were restricted to registered cows for ...
Genetic Aspects of Growth of Holstein-Friesian Dairy Cows from Birth to Maturity
Jan 01, 2006; ... ABSTRACT In general, genetic selection is applied after first calving to traits that manifest themselves during the animal's productive life, mostly during the early part of productive life. This selection policy has had undesirable correlated responses in other economically important ...
Performance and Feeding Behavior of Primiparous Cows Loose Housed Alone or Together with Multiparous Cows
Jan 01, 2006; ... ABSTRACT Lactating Holstein cows (52 multiparous and 90 primiparous) were monitored over a period of 10 mo to observe effects of grouping primiparous cows (PPC) separately from multiparous cows (MPC) on performance, feeding behavior, feed intake, feed efficiency, and milk production of ...
Direct-Fed Microbial Supplementation on Ruminal Digestion, Health, and Performance of Pre- and Postpartum Dairy Cattle
Jan 01, 2006; ... ABSTRACT Effects of supplementing direct-fed microbial agents (DFM) to dairy cows during the transition period were evaluated. Forty-four Holstein cows were fed close-up and lactating diets that did or did not contain 2 g of DFM/cow per d. Direct-fed microbial supplementation contained ...
Supplementation with Extruded Linseed Cake Affects Concentrations of Conjugated Linoleic Acid and Vaccenic Acid in Goat Milk
Jan 01, 2006; ... ABSTRACT The aim of this research was to determine the effect of adding extruded linseed cake to the dry diet of goats on the concentrations of conjugated linoleic acid (CLA) and vaccenic acid (VA) in milk fat. Thirty crossbreed dairy goats were divided into 3 groups. Their diet was ...
Prediction and Evaluation of Urine and Urinary Nitrogen and Mineral Excretion from Dairy Cattle
Jan 01, 2006; ... ABSTRACT Urine excretion is a substantial factor in the amount of manure that needs to be managed, and urinary N can contribute to ammonia volatilization. Development and validation of prediction equations focusing on dietary factors to decrease urine and urinary nutrient excretion will ...
Development and Evaluation of Models to Predict the Feed Intake of Dairy Cows in Early Lactation
Jan 01, 2006; ... ABSTRACT Inaccurate prediction of dry matter intake (DMI) limits the ability of current models to anticipate the technical and economic consequences of adopting different strategies for production management on individual dairy farms. The objective of the present study was to develop an ...
Wrong and Missing Sire Information Affects Genetic Gain in the Angeln Dairy Cattle Population
Jan 01, 2006; ... ABSTRACT In the present study, molecular genetic markers were used to help estimate the degree of wrong sire information in the German Angeln dairy cattle population. Sixteen polymorphic microsatellite markers were genotyped on 5 different paternal half-sib families with a total of 805 ...
Genetic Analysis of Clinical Mastitis Data from On-Farm Management Software Using Threshold Models
Jan 01, 2006; ... ABSTRACT Producer-recorded clinical mastitis data from 77,791 cows in 418 herds were used to determine the potential for genetic improvement of mastitis resistance using data from on-farm management software programs. The following threshold sire models were applied: 1) a single-trait ...
Students' Perception of a Discussion-Driven Classroom Environment in an Upper-Level Ruminant Nutrition Course with Small Enrollment
Jan 01, 2006; ... ABSTRACT This 3-yr classroom research project studied students' perception of the learning environment when class time was reserved primarily for discussion of preassigned reading material as an alternative to a lecture in ruminant nutrition. A student-assessment-of-learning-gain ...
Trends in Calving Ages and Calving Intervals for Dairy Cattle Breeds in the United States
Jan 01, 2006; ... ABSTRACT Trends since 1980 for calving age and calving interval, 2 factors that influence herd life, were examined by parity for 5 breeds of US dairy cattle. Calving data were from cows with records that passed edits for USDA genetic evaluations and were in herds that remained on Dairy ...
NEWS AND EVENTS
Jan 01, 2006; ... Positions Available. . . The deadline for the submission of position announcements for publication in the Journal of Dairy Science is the 25th day of the month, two months preceding the month of issue. For example, ads submitted by May 25 will be printed in the July issue of the ...