Short communication: Variability in milk urea nitrogen and dairy total mixed ration composition in the northeastern United States

The main objective of this survey was to examine variability in milk urea nitrogen (MUN) for Dairy Herd Improvement Association (DHIA) herds in the northeastern United States (the Northeast), examine trends in dairy cow diet composition, and determine potential relationships for MUN and diet composition. Trends in milk fat and protein concentrations, milk yield, days in milk on test day, and lactation number of the cows were also evaluated. The data set for the survey included 10,839,461 DHIA dairy cow records from 2004 to 2015 for 13 states (CT, DE, MA, MD, ME, NH, NJ, NY, PA, RI, VA, VT, and WV) and was retrieved from Dairy Records Management Systems (Raleigh, NC). Average (across states and years) milk yield, milk fat, and milk protein were 31.6 ± 0.24 kg/d, 3.85 ± 0.021%, and 3.13 ± 0.013%, respectively. No obvious trends were observed for milk fat or protein content, but milk yield steadily increased during the survey period. Milk urea N concentration averaged 13.3 ± 0.13 mg/dL, with no obvious or consistent trends. Examination of variability in dairy feed cost and all milk price for the Northeast indicated that high MUN generally coincided with high feed cost and high milk price. For the diet composition survey, 9,707 records of total mixed ration (TMR) analyses, unrelated to the milk composition data set, from the Cumberland Valley Analytical Service (Maugansville, MD) database were examined. Concentration of TMR crude protein (CP) decreased from 17.1% in 2007 to 16.4% in 2015, but there was not an obvious trend in soluble protein concentration. Concentration of TMR neutral detergent fiber (NDF) and 24-h in vitro NDF degradability declined steadily during the survey period and was accompanied by a steady increase in TMR starch concentration. Examination of these unrelated data sets revealed lack of correlation between MUN and diet chemical composition. Thus, we conclude that individual cow MUN in Northeast dairy herds fluctuated between 2004 and 2015. It appeared that MUN followed variability in feed cost; however, ration feed ingredient data were not available to better define the reasons for the variations in MUN.     

Short communication: Increased somatic cell count is associated with milk loss and reduced feed efficiency in lactating dairy cows

The objective was to evaluate the relationship of somatic cell count (SCC; cells/mL) with milk yield, energy-corrected milk yield (ECM; kg/d), dry matter intake (DMI; kg/d), feed efficiency for milk (FE_MY; kg of milk/kg of DMI), and feed efficiency for ECM (FE_ECM; kg of ECM/kg of DMI) in lactating dairy cows. We analyzed an SCC database consisting of 7 experiments, which were conducted at The Pennsylvania State University's Dairy Teaching and Research Center between 2009 and 2015. The experiments included in the SCC database were randomized block designs and investigated dietary effects on cow performance over 6 to 11 wk. Each experiment took repeated measurements of SCC, milk yield, milk composition, and DMI. After exclusion of records from cows without lactation number, days in milk, and only 1 measurement, the database comprised 1,094 observations of 254 cows for estimating the effect of SCC on milk yield, DMI, and FE_MY and 1,079 observations of 250 cows for estimating the effect of SCC on ECM and FE_ECM. Data were analyzed in R using a linear mixed model with natural logarithm of SCC, lactation number (1, 2, and ≥3), days in milk, and the interactions of the linear predictors as fixed effects and cow within block and experiment as random effect. Natural logarithm of SCC was negatively correlated with milk yield, ECM, DMI, FE_MY, and FE_ECM. Our results suggest that a cow with relatively high SCC (250,000 cells/mL) compared with a cow with a relatively low SCC (50,000 cells/mL) produces, on average, 1.6 kg/d less milk, consumes 0.3 kg/d less DMI, produces 0.04 kg less milk per kg of DMI, and produces 0.03 less ECM per kg of DMI. The observed decrease of feed efficiency with increased SCC adds to previously known economic losses and environmental impacts associated with mastitis, which should provide a further incentive to control mastitis in dairy cows.     

A Hybrid Fast Multipole Pseudo-Spectral Time Domain Method

The major computation cost of pseudo-spectral method comes from the evaluation of differentiation matrix multiplication. In the past, uniform or Chebyshev collocation points are used for sampling. The differentiation matrix multiplication was evaluated by fast Fourier transform (FFT) or fast cosine transform (FCT), in order to reduce the computation complexity from O(N²) to O(N log(N)). However, the intrinsic properties of FFT or FCT may cause the wraparound effect and Gibbs phenomenon. Moreover, FFT or FCT is not applicable to other collocation points such as Legendre and Hermite. In order to improve the accuracy and applicability of the pseudo-spectral method, the fast multipole method (FMM) is exploited to substitute the FFT or FCT. By making use of the similarity of the N-body problem and the collocation problem, a new FMM-based pseudo-spectral time domain method is developed in this paper.     

New One-Generator Quasi-cyclic Codes over GF(7)

Let [n,k,d] _q codes be linear codes of length n, dimension k, and minimum Hamming distance d over GF(q). In this paper, seventeen new codes are constructed, which improve the known lower bounds on minimum distance.     

The 5N neutral particle beamline of the U-70 accelerator (Institute for High Energy Physics)

The 5N neutral particle beamline at the U-70 accelerator (Institute for High Energy Physics), which has been designed to produce a high-intensity neutron beam with the highest possible energy, is described. The average neutron energy is ∼51 GeV, and the beam intensity is up to 10⁷ neutrons per spill. For several years, this beam has been used to investigate charmed particles and narrow baryon resonances in neutron-nucleus interactions and search for exotic multiquark states with the aid of the EXCHARM spectrometer. Original Russian Text A.N. Aleev, V.A. Arefiev, A.A. Aseev, Yu.G. Basha, V.P. Balandin, A.P. Bugorsky, T.S. Grigalashvili, B.N. Guskov, A.A. Zhuravlev, V.N. Zapolsky, A.I. Zinchenko, I.M. Ivanchenko, N.N. Karpenko, M.N. Kapishin, V.D. Kekelidze, D.A. Kirillov, I.G. Kosarev, N.A. Kuzmin, M.F. Likhachev, A.L. Ljubimov, D.T. Madigozhin, A.N. Maximov, N.A. Molokanova, A.N. Morozov, F.N. Novoskoltsev, Yu.K. Potrebenikov, Yu.P. Petukhov, V.E. Simonov, V.N. Spaskov, G.T. Tatishvili, P.Z. Hristov, I.P. Yudin (EXCHARM Collaboration), 2009, published in Pribory i Tekhnika Eksperimenta, 2009, No. 3, pp. 5–12.     

Effect of Saccharomyces cerevisiae fermentation product on ruminal fermentation and nutrient utilization in dairy cows

The goal of this experiment was to investigate the effect of yeast culture (Saccharomyces cerevisiae) on rumen fermentation, nutrient utilization, and ammonia and methane emission from manure in dairy cows. Eight ruminally cannulated Holstein cows were allocated to 2 dietary treatments in a crossover design. Treatments were control (no yeast culture) and XP (yeast culture, fed at 56 g/head per day; XP, Diamond V Mills Inc., Cedar Rapids, IA). Dry matter intake, milk yield, milk composition, and body weight were similar between treatments. Milk urea nitrogen concentration was also not affected by treatment. Rumen pH was similar between the control and XP treatments, but rumen ammonia concentration tended to be lower with XP than with the control. Treatment had no effect on concentrations of total or individual volatile fatty acids, protozoal counts, polysaccharide-degrading activities (except amylase activity that tended to be increased by XP), or methane production in the rumen. Urinary N losses did not differ significantly between treatments, but allantoin and total purine derivative excretions and the estimated microbial N outflow from the rumen tended to be increased by XP compared with the control treatment. Total-tract apparent digestibility of dietary nutrients was not affected by XP. Milk fatty acid composition was also not altered by XP supplementation. Cumulative (253 h) ammonia and methane emissions from manure, measured in a steady-state gas emission system, were slightly decreased by XP. Overall, the yeast culture tested had little effect on ruminal fermentation, digestibility, or N losses, but tended to reduce rumen ammonia concentration and increase microbial protein synthesis in the rumen, and decreased ammonia and methane emissions from manure.     

Effect of dietary carbohydrate composition and availability on utilization of ruminal ammonia nitrogen for milk protein synthesis in dairy cows

A trial with four ruminally and duodenally cannulated, late-lactation dairy cows was conducted to investigate the effect of dietary carbohydrate (CHO) composition and availability on ruminal ammonia N utilization and transfer into milk protein. Two diets were fed at 8-h intervals in a crossover design. The diets differed in CHO composition: the ruminally fermentable non-structural carbohydrates (RFSS) diet (barley and molasses) contained a larger proportion of ruminally available CHO in the nonstructural carbohydrate fractions and the ruminally fermentable fiber (RFNDF) diet (corn, beet pulp, and brewer's grains) contained a larger proportion of CHO in ruminally available fiber. Nitrogen-15 was used to label ruminal ammonia N and consequently microbial and milk N. Fermentation acids, enzyme activities, and microbial protein production in the rumen were not affected by diet. Ruminal ammonia concentration was lowered by RFNDF. Ruminal and total tract digestibility of nutrients did not differ between diets except that apparent ruminal degradability of crude protein was lower for RFNDF compared with RFSS. Partitioning of N losses between urine and feces was also not affected by diet. Milk yield and fat and protein content were not affected by treatment. Average concentration of milk urea N was lower for RFNDF than for RFSS. Proportion of milk protein N originating from ruminal microbial N (based on the areas under the 15N-enrichment curves) was higher for RFNDF than for RFSS. Cumulative recovery of 15N in milk protein was 13% higher for RFNDF than for RFSS indicating enhanced transfer of 15N-ammonia into milk protein with the former diet. The results suggested that, compared to diets containing higher levels of ruminally fermentable starch, diets providing higher concentration of ruminally fermentable fiber may enhance transfer of ruminal ammonia and microbial N into milk protein.     

Traffimatics — Intelligent Co-Operative Vehicle Highway Systems

This paper describes the vision of the Traffimatics project — the vision of the connected car. Traffimatics aims to develop the concept of intelligent co-operative vehicle highway systems, supporting a wide range of applications ranging from real-time traffic information and safety warnings to in-car entertainment and personal telematics. The project also investigates the possibilities of using vehicles to create a large-scale self-organising sensor and communications network enabling the intelligent co-operative vehicle highway systems vision. This paper looks into the state-of-the-art technologies that could enable the Traffimatics vision and also discusses market barriers and opportunities.