Journal of Dairy Science back issues from February 2007:
NEWS AND ANNOUNCEMENTS
Feb 01, 2007; ... ADSA Member News ... ADSA Announces Search for Director, DISCOVER Conferences After successfully launching the DISCOVER Conferences Series in 1997, and then directing each of the next 11 conferences, Bill Baumgardt has decided that the time has come to pass the reins. Accordingly, ...
Bovine [alpha]-Lactalbumin Stimulates Mucus Metabolism in Gastric Mucosa
Feb 01, 2007; ... ABSTRACT Bovine α-lactalbumin (α-LA), a major milk protein, exerts strong gastroprotective activity against rat experimental gastric ulcers induced by ethanol or stress. To elucidate the mechanisms underlying this activity, the influence of α-LA on gastric mucus metabolism ...
Antioxidant Nature of Bovine Milk [beta]-Lactoglobulin
Feb 01, 2007; ... ABSTRACT Heating is necessary for processing milk in the dairy industry, which evidently produces a conformational change in β-lactoglobulin (β-LG). β-Lactoglobulin, a major protein that accounts for approximately 10 to 15% of total milk proteins, is a globular protein ...
Binding of Aflatoxin M^sub 1^ to Different Protein Fractions in Ovine and Caprine Milk
Feb 01, 2007; ... ABSTRACT The affinity of aflatoxin M^sub 1^ toward the main milk protein fractions in ewe and goat milk was investigated by using an ELISA. This study took into account the possible effects of common dairy processes such as ultrafiltration, acidic or rennet curding, and production of ...
Study on the Influence of Pasture on Volatile Fraction of Ewes' Dairy Products by Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry
Feb 01, 2007; ... ABSTRACT The detection of markers of identification of the geographical origin of food is an attractive challenge and, as far as dairy products are concerned, this paper represents a contribution to this field. In this research the influence of feed on the volatile compound composition ...
Solvent Type Affects the Number, Distribution, and Relative Quantities of Volatile Compounds Found in Sweet Whey Powder
Feb 01, 2007; ... ABSTRACT This study compares the performance of diethyl ether, methylene chloride, methyl formate, and pentane in the analysis of volatile flavor components in sweet whey powder. Extracts were prepared from sweet whey powder using each solvent. Volatile components were isolated by ...
Effect of [beta]-Lactoglobulin A and B Whey Protein Variants on the Rennet-Induced Gelation of Skim Milk Gels in a Model Reconstituted Skim Milk System
Feb 01, 2007; ... ABSTRACT The effect of fortifying reconstituted skim milk with increasing levels of the β-lactoglobulin (β-LG) genetic variants A, B, and an A-B mixture on rennet-induced gelation was studied by small deformation-sensitive rheology. Free-zone capillary electrophoresis and ...
Valuation of Milk Composition and Genotype in Cheddar Cheese Production Using an Optimization Model of Cheese and Whey Production
Feb 01, 2007; ... ABSTRACT A mass balance optimization model was developed to determine the value of the κ-casein genotype and milk composition in Cheddar cheese and whey production. Inputs were milk, nonfat dry milk, cream, condensed skim milk, and starter and salt. The products produced were ...
Dairy Powder Rehydration: Influence of Protein State, Incorporation Mode, and Agglomeration
Feb 01, 2007; ... ABSTRACT A simplified method to study rehydration was used on different dairy powders. The method involved dispersing powder in a stirred vessel equipped with a turbidity sensor. The changes of turbidity occurring during powder rehydration highlighted the rehydration stage, and the ...
Enzymatic Interesterification of Tripalmitin with Vegetable Oil Blends for Formulation of Caprine Milk Infant Formula Analogs
Feb 01, 2007; ... ABSTRACT The structure of triacylglycerols in vegetable oil blends was enzymatically modified, and the blends were incorporated into skim caprine milk to produce goat milk-based infant formula analogs, homologous to human milk. A modified lipid containing palmitic, oleic, and linoleic ...
Relationships Among Milk Production, Energy Balance, Plasma Analytes, and Reproduction in Holstein-Friesian Cows
Feb 01, 2007; ... ABSTRACT Associations were examined between components and indicators of early lactation energy balance (EB) and measures of fertility in Holstein cows. Milk production, dry matter intake (DMI), body condition score (BCS), and endocrine and metabolite data from 96 cows were analyzed ...
Short Communication: Ability of Cultured Mammary Epithelial Cells in a Bicameral System to Secrete Milk Fat
Feb 01, 2007; ... ABSTRACT Mammary epithelial cells from lactating cows were cultured onto inserts coated with type I collagen. Every second day, the rates of fatty acid synthesis and secretion were determined by measuring the amount of [^sup 14^C]-labeled sodium acetate incorporated into lipids over a ...
Production Effects of Pathogens Causing Bovine Leukosis, Bovine Viral Diarrhea, Paratuberculosis, and Neosporosis
Feb 01, 2007; ... ABSTRACT The primary purpose of this research was to determine associations among seropositivity for bovine leukemia virus (BLV), bovine viral diarrhea virus (BVDV), Mycobacterium avium ssp. paratuberculosis (MAP), and Neospora caninum (NC) and each of 3 outcome variables (305-d milk, ...
Effect of Somatic Cell Count on Prato Cheese Composition
Feb 01, 2007; ... ABSTRACT The objective of this research was to evaluate the effect of 2 levels of somatic cell counts (SCC) in raw milk on Prato cheese composition, protein and fat recovery, cheese yield, and ripening. A 2 × 6 factorial design with 3 replications was performed in this study: 2 levels of ...
Associations Among Body Condition Score, Body Weight, Somatic Cell Count, and Clinical Mastitis in Seasonally Calving Dairy Cattle
Feb 01, 2007; ... ABSTRACT The objective of this study was to determine if an association existed among body condition score (BCS), body weight (BW), and udder health, as indicated by somatic cell score (SCS) and cases of clinical mastitis (CM). The data consisted of 2,635 lactations from ...
Lipolysis and Proteolysis of Modified and Producer Milks Used for Calibration of Mid-Infrared Milk Analyzers1
Feb 01, 2007; ... ABSTRACT Our objective was to determine if lipolysis or proteolysis of calibration sets during shelf life influenced the mid-infrared (MIR) readings or calibration slopes and intercepts. The lipolytic and proteolytic deterioration was measured for 3 modified milk and 3 producer milk ...
Effect of Photoperiod in the Third Trimester of Gestation on Milk Production and Circulating Hormones in Dairy Goats
Feb 01, 2007; ... ABSTRACT Multiparous Israeli Saanen goats (n = 8) were blocked at dry off (approximately 45 d prepartum) into 2 treatments of 4 goats each based on body weight (BW), previous milk production, and the number of detected embryos in utero. Treatments consisted of long-day (16 h light:8 h ...
Effects of a Supplement Containing Trans-10, Cis-12 Conjugated Linoleic Acid on Bioenergetic and Milk Production Parameters in Grazing Dairy Cows Offered Ad Libitum or Restricted Pasture
Feb 01, 2007; ... ABSTRACT Conjugated linoleic acid (CLA) reduces milk fat synthesis in grazing dairy cows and may improve calculated net energy balance (EBAL). Study objectives were to determine whether CLA-induced milk fat depression could be utilized during times of feed restriction to improve ...
Incontinentia Lactis: Physiology and Anatomy Conducive to Milk Leakage in Dairy Cows
Feb 01, 2007; ... ABSTRACT Incontinentia lactis is a possible predisposing factor for an elevated level of intramammary infection. The goal of the present study was to investigate possible causes of incontinentia lactis in dairy cows. Two farms that differed in breed composition, but that had similar ...
Gait Pattern of Heifers Before and After Claw Trimming: A High-Speed Cinematographic Study on a Treadmill
Feb 01, 2007; ... ABSTRACT The manner in which the claws contacted the ground at the walk was evaluated in 18 healthy heifers. The animals were filmed before and after claw trimming while walking on a treadmill using high-speed cinematography (500 frames/s). For each limb, 4 consecutive steps were ...
Bovine Claw and Limb Disorders at Claw Trimming Related to Milk Yield
Feb 01, 2007; ... ABSTRACT As part of a cross-sectional study of Norwegian Red Cattle, associations of lameness, lesions at the tarsus, claw shapes, claw lesions, and claw trimming with milk yield were examined. Fifty-five tie-stall herds and 57 free-stall herds were sampled by computerized systematic ...
Effect of an Intramammary Teat Seal and Dry Cow Antibiotic in Relation to Dry Period Length on Postpartum Mastitis
Feb 01, 2007; ... ABSTRACT Infusion of either a long-acting antibiotic preparation (cefalonium) or the same antibiotic preparation combined with an internal teat sealant (bismuth subnitrite) were compared for the effect on new intramammary infections at calving and clinical mastitis in the first 100 d of ...
Effects of Dietary Vitamin C on Neutrophil Function and Responses to Intramammary Infusion of Lipopolysaccharide in Periparturient Dairy Cows
Feb 01, 2007; ... ABSTRACT Neutrophil function and the severity and incidence of mastitis in dairy cows is related to the intake of many antioxidant nutrients. Because vitamin C is the major water-soluble antioxidant in mammals, we examined the effect of dietary vitamin C on neutrophil function and ...
Factors Affecting the Concentration of Sphingomyelin in Bovine Milk1
Feb 01, 2007; ... ABSTRACT Sphingomyelin is a phospholipid located in the outer leaflet of the plasma membrane of most cells and is a component of the milk fat globule membrane. Sphingomyelin and its digestion products participate in several antiproliferative pathways that may suppress oncogenesis ....
Influence of Estrus of Dairy Goats on Somatic Cell Count, Milk Traits, and Sex Steroid Receptors in the Mammary Gland
Feb 01, 2007; ... ABSTRACT Two experiments were conducted to study the effect of the stage of a spontaneous estrus cycle on milk yield and constituents [somatic cell count (SCC), fat, protein, caseins, lactose, and urea content] and on estrogen receptor-α (ERα) and progesterone receptor (PR) ...
The Milk Yield Response to Frequent Milking in Early Lactation of Dairy Cows Is Locally Regulated
Feb 01, 2007; ... ABSTRACT Frequent milking during early lactation of dairy cows increases milk production throughout lactation; however, whether this response is regulated systemically via lactogenic hormones, locally in the mammary gland, or both is unknown. We hypothesized that the effects of frequent ...
Timed Artificial Insemination of Two Consecutive Services in Dairy Cows Using Prostaglandin F^sub 2[alpha]^ and Gonadotropin-Releasing Hormone
Feb 01, 2007; ... ABSTRACT Timed artificial insemination (TAI) protocols use PGF^sub 2α^ and GnRH injections to synchronize ovulation. The objective was to evaluate the PGPG protocol (d 0, PGF^sub 2α^; d 3, GnRH; d 11, PGF^sub 2α^; d 13, GnRH and TAI) for first TAI and also examine methods ...
Milk from Forage as Affected by Rumen Degradable Protein and Corn Grinding When Feeding Corn- and Alfalfa Silage-Based Diets
Feb 01, 2007; ... ABSTRACT To increase the production of milk from forage (MF), a previous experiment with alfalfa silage showed the importance of a complementary combination of concentrates and forages offered. When corn silage is fed with alfalfa, increasing the rumen degradable protein (RDP) content in ...
Ruminal Lipopolysaccharide Concentration and Inflammatory Response During Grain-Induced Subacute Ruminal Acidosis in Dairy Cows
Feb 01, 2007; ... ABSTRACT The effects of grain-induced subacute ruminal acidosis (SARA) in lactating dairy cows on free ruminal lipopolysaccharide (LPS) and indicators of inflammation were determined. Four mid lactation dairy cows were divided into 2 groups of 2 cows and used in a repeated switchover ...
Assessment of Ruminal Bacterial Populations and Protozoal Generation Time in Cows Fed Different Methionine Sources1
Feb 01, 2007; ... ABSTRACT Methionine supplemented as 2-hydroxy-4-(methylthio)-butanoic acid (HMB) has been suggested to alter bacterial or protozoal populations in the rumen. Our objective was to determine if source of Met would change microbial populations in the rumen and to compare those results to ...
Parenteral Treatment of Clinical Mastitis with Tylosin Base or Penethamate Hydriodide in Dairy Cattle
Feb 01, 2007; ... ABSTRACT The objective of this study was to compare the clinical and bacteriological cure rates of cows with clinical mastitis following treatment with either tylosin base (5 g injected 3 times at 24-h intervals; n = 306) or penethamate hydriodide (5 g injected 3 times at 24-h intervals; ...
Effects of Essential Oils on Digestion, Ruminal Fermentation, Rumen Microbial Populations, Milk Production, and Milk Composition in Dairy Cows Fed Alfalfa Silage or Corn Silage1
Feb 01, 2007; ... ABSTRACT Four Holstein cows fitted with ruminai cannulas were used in a 4 × 4 Latin square design (28-d periods) with a 2 × 2 factorial arrangement of treatments to investigate the effects of addition of a specific mixture of essential oil compounds (MEO; 0 vs. 750 mg/d) and silage ...
Occurrence of Selenoprotein Enzyme Activities and mRNA in Bovine Mammary Tissue
Feb 01, 2007; ... ABSTRACT To elucidate the possible role of selenoproteins for milk formation and mammary gland physiology, the activities of selenoprotein enzymes and the expression of selenoprotein genes were studied in the bovine mammary gland. Messenger RNA was demonstrated for selenoprotein P, ...
Effect of Heat and High-Pressure Treatments on Microbiological Quality and Immunoglobulin G Stability of Caprine Colostrum
Feb 01, 2007; ... ABSTRACT Caprine colostrums (6 batches) were subjected to heat (56°C for 60 min and 63°C for 30 min) and high-pressure (400 and 500 MPa for 10 min at 20°C) treatments at laboratory scale, and analyses of the main microbial groups and the extent of IgG denaturation (determined by ...
Streptococcus dysgalactiae Isolates at Calving and Lactation Performance Within the Same Lactation
Feb 01, 2007; ... ABSTRACT The objective of the study was to investigate the association between early lactation Streptococcus dysgalactiae isolates and milk yield, somatic cell count (SCC), clinical mastitis, and culling in the same lactation. The 178 commercial dairy herds were randomly placed into 3 ...
Ruminal Degradability and Intestinal Digestibility of Protein and Amino Acids in Treated Soybean Meal Products
Feb 01, 2007; ... ABSTRACT Four lactating dairy cows equipped with ruminal and duodenal cannulas were used to determine the impact of different methods of treating soybean meal (SBM) on the ruminal degradability and intestinal digestibility of crude protein and AA. Solvent-extracted SBM (SE), expeller SBM ...
Expression and Localization of Extracellular Matrix-Degrading Proteinases and Their Inhibitors in the Bovine Mammary Gland During Development, Function, and Involution
Feb 01, 2007; ... ABSTRACT In degrading the extracellular matrix, matrix metalloproteinases (MMP) and the plasminogen activator (PA) system may play a critical role in extensive remodeling that occurs in the bovine mammary gland during development, lactation, and involution. Therefore, the aim of our ...
Limit Feeding of Gravid Holstein Heifers: Effect on Growth, Manure Nutrient Excretion, and Subsequent Early Lactation Performance
Feb 01, 2007; ... ABSTRACT A study was conducted to evaluate the effect of limit feeding on growth, feed efficiency, and manure excretion in Holstein heifers and subsequent milk production. Fifty-four gravid Holstein heifers were randomly assigned to replicate pens and fed 1 of 3 experimental diets for ...
Effects of Dietary Cation-Anion Difference and Potassium to Sodium Ratio on Lactating Dairy Cows in Hot Weather
Feb 01, 2007; ... ABSTRACT Forty-two lactating Holstein cows 188 ± 59 d in milk were used in an 8-wk randomized complete block trial with a 2 × 3 factorial arrangement of treatments. The objective was to determine the effects of high dietary cation-anion difference (DCAD) and K:Na ratio on milk yield and ...
Effects of Two Different Feeding Strategies During Dry-off on Certain Health Aspects of Dairy Cows
Feb 01, 2007; ... ABSTRACT With increasing milk production and short calving intervals, high daily milk yields at dry-off are rather common, making the dry-off procedure difficult and increasing the risk for health problems during the dry-off period. The objective of the following study was to compare the ...
Pre- and Postweaning Performance of Holstein Female Calves Fed Milk Through Step-Down and Conventional Methods
Feb 01, 2007; ... ABSTRACT Milk consumption, dry feed intake, body weight (BW) gain, occurrence of diarrhea, and selected blood metabolites were studied in female Holstein calves fed milk either through conventional or step-down (STEP) methods. In conventional method, the calves (n = 20) were fed ...
Manipulation of Soluble and Rumen-Undegradable Protein in Diets Fed to Postpubertal Dairy Heifers1
Feb 01, 2007; ... ABSTRACT Eight postpubertal Holstein heifers (455 ± 4.0), fit with rumen cannulas, were used in 2 experiments to investigate the effects of altering dietary protein type on nutrient digestibility, rumen fermentation, and nitrogen utilization. Heifers were fed diets containing low or high ...
Effectiveness of Oils Rich in Linoleic and Linolenic Acids to Enhance Conjugated Linoleic Acid in Milk from Dairy Cows
Feb 01, 2007; ... ABSTRACT Forty Holstein dairy cows were used to determine the effectiveness of linoleic or linolenic-rich oils to enhance C^sub 18:2^ cis-9, trans-11 conjugated linoleic acid (CLA) and C^sub 18:1^ trans-11 (vaccenic acid; VA) in milk. The experimental design was a complete randomized ...
Concentrations of Butyric Acid Bacteria Spores in Silage and Relationships with Aerobic Deterioration
Feb 01, 2007; ... ABSTRACT Germination and growth of spores of butyric acid bacteria (BAB) may cause severe defects in semihard cheeses. Silage is the main source of BAB spores in cheese milk. The objectives of the study were to determine the significance of grass silages and corn silages as sources of ...
Measurement of Milk Intake in Suckling Llamas (Lama glama) Using Deuterium Oxide Dilution
Feb 01, 2007; ... ABSTRACT The objective of the study was to estimate daily milk intake in llama crias and relate nutrient intakes at peak lactation to growth data. Milk intake in 11 suckling llamas was estimated from water kinetics using deuterium oxide (D^sub 2^O) at d 17, 66, and 128 postpartum. Daily ...
Comparative Evaluation of Alternative Forages to Grass Silage in the Diet of Early Lactation Dairy Cows
Feb 01, 2007; ... ABSTRACT Fifty-six autumn-calving Holstein-Friesian cows, blocked on the basis of days in milk (27.6 ± 10.65 d), lactation number (3.1 ± 2.21), and preexperimental milk yield (28.4 ± 6.69 kg) were used to examine the effects of replacing 330 g/kg of dry matter (DM) of firstcut perennial ...
Analysis of the Sheep MUC1 Gene: Structure of the Repetitive Region and Polymorphism
Feb 01, 2007; ... ABSTRACT An investigation was undertaken with the aim of studying the repetitive region of the MUC1 gene and analyzing its polymorphisms in some Italian sheep breeds. Two primers previously used for the goat MUC1 gene analyses allowed for the amplification of 4 different alleles. The ...
Exploring the Use of Random Regression Models with Legendre Polynomials to Analyze Measures of Volume of Ejaculate in Holstein Bulls
Feb 01, 2007; ... ABSTRACT Artificial insemination centers routinely collect records of quantity and quality of semen of bulls throughout the animals' productive period. The goal of this paper was to explore the use of random regression models with orthogonal polynomials to analyze repeated measures of ...
Effect of Varying Levels of Fatty Acids from Palm Oil on Feed Intake and Milk Production in Holstein Cows
Feb 01, 2007; ... ABSTRACT To determine the optimum feeding level of fatty acids of palm oil (PALM; Energizer RP10; 86.6% palmitic acid) on milk production, lactating cows (n = 18) were randomly assigned to a treatment sequence in replicated 4 × 4 Latin squares. Animals were assigned to squares by parity ...
Effects of Prepartum Administration of a Monensin Controlled Release Capsule on Rumen pH, Feed Intake, and Milk Production of Transition Dairy Cows
Feb 01, 2007; ... ABSTRACT Effects of prepartum administration of a monensin controlled release capsule (CRC) on rumen pH, dry matter intake, and milk production during the transition period and early lactation were determined in 16 multiparous Holstein cows. Cows were divided into blocks of 2 depending ...
Development of a Mechanistic Model to Represent the Dynamics of Liquid Flow Out of the Rumen and to Predict the Rate of Passage of Liquid in Dairy Cattle
Feb 01, 2007; ... ABSTRACT A mechanistic and dynamic model was developed to represent the physiological aspects of liquid dynamics in the rumen and to quantitatively predict liquid flow out of the reticulorumen (RR). The model is composed of 2 inflows (water consumption and salivary secretion), one ...
Voluntary Waiting Period Management Practices in Dairy Herds Participating in a Progeny Test Program
Feb 01, 2007; ... ABSTRACT A survey was mailed to approximately 4,000 herds participating in a young sire progeny test program to estimate the percentage of herds that selectively alter the voluntary waiting period (VWP) for individual cows or groups of cows. Responses were received from 673 herds (17%; ...
Selection on Yield and Fitness Traits When Culling Holsteins During the First Three Lactations
Feb 01, 2007; ... ABSTRACT Emphasis by dairy producers on various yield and fitness traits when culling cows was documented for US Holstein calvings since 1982. Least squares differences between cows retained for additional parities and those culled were estimated for milk, fat, and protein yields; ...
Isolation of Bovine Immunoglobulins Resistant to Peptic Digestion: New Perspectives in the Prevention of Failure in Passive Immunization of Neonatal Calves
Feb 01, 2007; ... ABSTRACT In calves, neonatal mortality and disease susceptibility are greatly influenced by failure in passive immunization, normally provided by colostrum ingestion just after birth. Formulations projected to replace natural colostrum have not been successful, and one of the possible ...
The Effect of Solids Dilution Rate and Oil Source on Trans C18:1 and Conjugated Linoleic Acid Production by Ruminal Microbes in Continuous Culture
Feb 01, 2007; ... ABSTRACT The objective of this study was to evaluate the effect of solids dilution rate (SDR) and oil source [soybean oil (SBO) or linseed oil (LSO)] on the ruminai production of trans C18:1 and conjugated linoleic acid (CLA). A dual-flow continuous culture system consisting of 4 ...
Association of Bovine Leukocyte Antigen (BoLA) DRB3.2 with Immune Response, Mastitis, and Production and Type Traits in Canadian Holsteins
Feb 01, 2007; ... ABSTRACT Data collected from 328 Canadian Holsteins in a research herd at the University of Guelph were used to study associations among expression of bovine leukocyte antigen (BoLA) DRB3.2 alleles, immune response, mastitis resistance via somatic cell counts (SCC), and clinical ...
Short Communication: Genetic Evaluation of Milking Speed for Brown Swiss Dairy Cattle in the United States
Feb 01, 2007; ... ABSTRACT Genetic parameters and relative breeding values were estimated for milking speed of US Brown Swiss dairy cattle. Owner-recorded milking-speed scores on a scale of 1 (slow) to 8 (fast) were collected by the Brown Swiss Association as part of its linear type appraisal program ...
Short Communication: Identification of Diseased Calves by Use of Data from Automatic Milk Feeders
Feb 01, 2007; ... ABSTRACT Housing calves in large groups is associated with a higher risk of respiratory disease and with increased difficulties in identifying diseased animals compared with single housing. The aim of the present study was to investigate the effect of clinical disease on some behaviors ...
Bacterial Counts in Organic Materials Used as Free-Stall Bedding Following Treatment with a Commercial Conditioner1
Feb 01, 2007; ... ABSTRACT An acidic conditioner was tested in recycled manure and sawdust used as free-stall bedding to determine the effect on bacterial counts of common environmental mastitis pathogens. Free stalls were bedded with 10 kg of either kiln-dried sawdust or recycled manure per stall. All ...
Goat Acetyl-Coenzyme A Carboxylase [alpha]: Molecular Characterization, Polymorphism, and Association with Milk Traits
Feb 01, 2007; ... ABSTRACT Acetyl-coenzyme A carboxylase α (ACACA), the major regulatory enzyme of fatty acid biosynthesis, catalyzes the conversion of acetyl-CoA to malonyl-CoA. We have sequenced 5.5 kb of the goat ACACA cDNA in 18 individuals. The translated cDNA sequence encodes 1,832 AA and ...
The Effect of Formulation and Amount of Potassium Fertilizer on Macromineral Concentration and Cation-Anion Difference in Tall Fescue
Feb 01, 2007; ... ABSTRACT This study investigated the feasibility of altering the dietary cation-anion difference (DCAD) in grass by altering the grass variety and the amount and formulation of K fertilizer application. In experiment 1, treatments were combinations of 2 varieties (Barcel and HiMag) of ...