Evaluation of warm season annual forages for forage yield and quality in the north-central United States.

Grazing-based dairy operations require productive, high-quality forages capable of supporting the nutritional needs of mid-lactation dairy cows. Our objectives were to evaluate primary and regrowth harvests of two cultivars of sudangrass (SU), sorghum-sudangrass (S×SU), and pearl millet (PM) forages for growth and nutritive characteristics within the specific context of suitability for grazing by dairy cows. Three harvest cycles, including primary and regrowth cycles in 2016, and a single harvest cycle of primary growth in 2017, were evaluated at two locations (Prairie du Sac and Marshfield, WI).

Brisket Disease Is Associated with Lower Volatile Fatty Acid Production and Altered Rumen Microbiome in Holstein Heifers.

Brisket disease is heritable but is also associated with non-genetic risk factors and effects of the disease on the rumen microbiome are unknown. Ten Holstein heifers were exposed to the plateau environment for three months and divided into two groups according to the index of brisket disease, the mean pulmonary arterial pressure (mPAP): brisket disease group (BD, n = 5, mPAP > 63 mmHg) and healthy heifer group (HH, n = 5, mPAP < 41 mmHg). Rumen fluid was collected for analysis of the concentrations of volatile fatty acids (VFAs).

Validating the Use of Bovine Buccal Sampling as a Proxy for the Rumen Microbiota by Using a Time Course and Random Forest Classification Approach.

Analysis of the cow microbiome, as well as host genetic influences on the establishment and colonization of the rumen microbiota, is critical for development of strategies to manipulate ruminal function toward more efficient and environmentally friendly milk production. To this end, the development and validation of noninvasive methods to sample the rumen microbiota at a large scale are required. In this study, we further optimized the analysis of buccal swab samples as a proxy for direct bacterial samples of the rumen of dairy cows.

Changes in the host transcriptome and microbial metatranscriptome of the ileum of dairy calves subjected to artificial dosing of exogenous rumen contents.

Development of a properly functioning gastrointestinal tract (GIT) at an early age is critical for the wellbeing and lifetime productivity of dairy cattle. The role of early microbial colonization on GIT development in neonatal cattle and the associated molecular changes remain largely unknown, particularly for the small intestine. In this study, we performed artificial dosing of exogenous rumen fluid during the early life of the calf, starting at birth through the weaning transition at 8 wk.

Effects of feedbunk restrictions and push-up frequency on the growth performance of Holstein dairy heifers offered a forage-based diet with a limit-feeding strategy.

Conceptually, there are 2 feeding strategies for avoiding over-conditioning, which can be problematic for gravid dairy heifers that have reduced dietary energy density requirements relative to younger animals: (1) diluting the ad libitum-fed diet with low-energy forages; or (2) offering a diet of greater nutrient density but intentionally restricting the DM available for consumption (limit-feeding). Our objectives for this study were to evaluate the effects of feedbunk restriction and feed push-up frequency on the growth performance of gravid Holstein dairy heifers. A total of 128 Holstein heifers (434 ± 46.

Symposium review: Advances in sequencing technology herald a new frontier in cattle genomics and genome-enabled selection.

The cattle reference genome assembly has underpinned major innovations in beef and dairy genetics through genome-enabled selection, including removal of deleterious recessive variants and selection for favorable alleles affecting quantitative production traits. The initial reference assemblies, up to and including UMD3.1 and Btau4.

Bacterial community composition of vermicompost-treated tomato rhizospheres.

Vermicompost application has been shown to promote plant growth, alter the rhizosphere microbiome, and suppress plant pathogens. These beneficial properties are often attributed to the activity of vermicompost-associated microorganisms. However, little is known about the microbial shifts that occur in the rhizosphere after vermicompost application.

Symposium review: Strategies to improve the efficiency and profitability of heifer raising.

Regional Research Project NC-2042 has a main objective to study calf and heifer nutrition. Within this objective, feeding the postweaned heifer is considered a major priority to improve the profitability and sustainability of US dairy farms. Through optimizing nutrient utilization by precision feeding, using alternative feeds, high-fiber diets, and feed additives, this research group has worked to enhance dairy heifer nutrition.

Nutrient Intake, Excretion and Use Efficiency of Grazing Lactating Herds on Commercial Dairy Farms.

Estimating excreted nutrients is important for farm nutrient management, but seldom occurs on commercial grazing system farms due to difficulties in quantifying pasture intake. Nitrogen (N), phosphorus (P), potassium (K), sulphur (S), calcium (Ca) and magnesium (Mg) intake, excretion and use efficiency of 43 commercial dairy herds grazing pasture were calculated to understand the range in nutrient intake and excretion in these systems. Milk production, feed (grazed and supplement), as well as farm and herd management data were collected quarterly on representative farms located in temperate, arid, subtropical and tropical regions of Australia.

Development of feed composition tables using a statistical screening procedure.

Millions of feed composition records generated annually by testing laboratories are valuable assets that can be used to benefit the animal nutrition community. However, it is challenging to manage, handle, and process feed composition data that originate from multiple sources, lack standardized feed names, and contain outliers. Efficient methods that consolidate and screen such data are needed to develop feed composition databases with accurate means and standard deviations (SD).

The bovine epimural microbiota displays compositional and structural heterogeneity across different ruminal locations.

Dairy cattle are globally important agricultural animals. Central to their biology is the rumen, which houses an essential microbial community, or microbiome, important for providing nutrition from otherwise host-inaccessible dietary components. The rumen environment is noted for its substantial spatial heterogeneity, as illustrated by the stratification into ruminal solid and liquid phases.

Fermentation characteristics and nutritive value of baled grass silages made from meadow fescue, tall fescue, or an orchardgrass cultivar exhibiting a unique nonflowering growth response.

Throughout central Wisconsin, many soils are poorly drained, and perennial cool-season grasses are often planted as monocultures or in mixed stands with alfalfa because of the poor persistence of alfalfa under these growing conditions. Our objectives were to compare the fermentation characteristics and nutritive value of perennial cool-season grasses {meadow fescue [Schedonorus pratensis (Huds.) P.

Symposium review: Nutrition strategies for improved health, production, and fertility during the transition period.

Dairy cow nutritional programs are a major determinant of the profitability of dairy farms. Despite this, the sustainability of the dairy enterprise is beyond just cow nutrition. For almost 50 yr, the NC-2042 project (Management Systems to Improve the Economic and Environmental Sustainability of Dairy Enterprises) has been addressing most of these components as individual research units and in integrated ways.

Comparison of Protein Precipitation Ability of Structurally Diverse Procyanidin-Rich Condensed Tannins in Two Buffer Systems.

The protein precipitation (PP) of bovine serum albumin (BSA), lysozyme (LYS), and alfalfa leaf protein (ALF) by four procyanidin-rich condensed tannin (CT) samples in both 2-[-morpholino]ethanesulfonic acid (MES) and a modified Goering-Van Soest (GVS) buffer is described. Purified CT samples examined included seed (mean degree of polymerization [mDP] 4.1, 16.

Physiological effects of starter-induced ruminal acidosis in calves before, during, and after weaning.

The objectives were to nutritionally induce or blunt ruminal acidosis in young calves and to compare indicators of rumen and systemic health. Ten bull calves (n = 5/diet) were ruminally cannulated at 3 wk of age and received milk replacer and 1 of 2 calf starter diets that were designed to cause (AC; pelleted, 42.7% starch, 15.

Effects of feeding a quebracho-chestnut tannin extract on lactating cow performance and nitrogen utilization efficiency.

The effects of feeding a quebracho-chestnut tannin extract mixture on performance and nitrogen (N) utilization were assessed with 36 multiparous lactating Holstein cows (mean ± standard deviation; 706 ± 59 kg of body weight; 126 ± 20 d in milk) randomly assigned to 3 dietary treatments in a randomized complete block design. Following a 2-wk covariate adjustment period, cows were fed their assigned treatment diets for 13 wk. Rice hulls were removed from a total mixed ration with a 54:46 forage:concentrate ratio (% of dry matter; DM), and a tannin extract mixture from quebracho and chestnut trees (2:1 ratio) was included at 0, 0.

Changes in meta-transcriptome of rumen epimural microbial community and liver transcriptome in young calves with feed induced acidosis.

The common management practices of dairy calves leads to increased starch concentration in feed, which subsequently may cause rumen acidosis while on milk and during weaning. Until recently, few attempts were undertaken to understand the health risks of prolonged ruminal acidosis in post weaning calves. Resultantly, the molecular changes in the digestive tracts in post-weaning calves with ruminal acidosis remain largely unexplored.

Identification of Single Nucleotide Polymorphism in Red Clover () Using Targeted Genomic Amplicon Sequencing and RNA-seq.

Red clover () is a diploid, naturally cross-pollinated, cool-season species. As a perennial forage legume, red clover is mostly cultivated in temperate regions worldwide. Being a non-model crop species, genomic resources for red clover have been underdeveloped.

Comparison of feeding diets diluted with sorghum-sudangrass silage or low-quality grass on nutrient intake and digestibility and growth performance of Holstein dairy heifers.

This study was carried out to evaluate the nutrient intakes and growth of dairy heifers offered an alfalfa silage-corn silage diet (CON; 14.3% crude protein, 61.1% total digestible nutrients, 47.

Performance of dairy cows fed diets formulated at 2 starch concentrations with either canola meal or soybean meal as the protein supplement.

This study was designed to evaluate the effects of substituting corn grain with nonforage fiber sources in diets containing soybean meal (SBM) or canola meal (CM) as the primary protein source. Sixteen Holstein cows were assigned to a replicated 4 × 4 Latin square design with 4 periods of 28 d each. Treatments were arranged as a 2 × 2 factorial with 2 protein sources (SBM and CM) and 2 dietary starch concentrations (21 and 27% dry matter, DM).

Ruminal fermentation, kinetics, and total-tract digestibility of lactating dairy cows fed distillers dried grains with solubles in low- and high-forage diets.

The objective of this study was to investigate the effects of concentrations of forages and corn distillers dried grains with solubles (DDGS) on ruminal fermentation, ruminal kinetics, and total-tract digestibility of nutrients in lactating dairy cows. Four lactating Holstein cows with ruminal cannulas were assigned to a 4 × 4 Latin square in a 2 × 2 factorial arrangement of treatments. Diets were formulated to contain low forage [LF; 17% forage neutral detergent fiber (NDF)] or high forage (HF; 24.

Effects of sample size on neutral detergent fiber digestibility of triticale forages using the Ankom Daisy Incubator system.

Accurate and precise determinations of fiber digestibility are essential for proper diet formulation for dairy cows. Our objectives were 3-fold: (1) regress in vitro neutral detergent fiber digestibility (NDFD) values from 48 triticale forages determined at multiple endpoints ranging from 12 to 240 h with Ankom Daisy Incubator system (Ankom Technology Corp., Macedon, NY) methods using 0.