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Circadian disruption increased insulin resistance and decreased mammary development in late gestation, nonlactating (dry) cows. The objective was to measure the effect of circadian disruption on transcriptomes of the liver and mammary gland. At 35 days before expected calving (BEC), multiparous dry cows were assigned to either control (CON) or phase-shifted treatments (PS). CON was exposed to 16-h light and 8-h dark. PS was exposed to 16-h light to 8-h dark, but phase of the light-dark cycle was shifted 6 h every 3 days. On day 21 BEC, liver and mammary were biopsied. RNA was isolated ( n = 6 CON, n = 6 PS per tissue), and libraries were prepared and sequenced using paired-end reads. Reads mapping to bovine genome averaged 27 ± 2 million and aligned to 14,222 protein-coding genes in liver and 15,480 in mammary analysis. In the liver, 834 genes, and in the mammary gland, 862 genes were different (nominal P < 0.05) between PS and CON. In the liver, genes upregulated in PS functioned in cholesterol biosynthesis, endoplasmic reticulum stress, wound healing, and inflammation. Genes downregulated in liver function in cholesterol efflux. In the mammary gland, genes upregulated functioned in mRNA processing and transcription and downregulated genes encoded extracellular matrix proteins and proteases, cathepsins and lysosomal proteases, lipid transporters, and regulated oxidative phosphorylation. Increased cholesterol synthesis and decreased efflux suggest that circadian disruption potentially increases the risk of fatty liver in cows. Decreased remodeling and lipid transport in mammary may decrease milk production capacity during lactation.

Metabolizable protein supply is a limiting factor for milk production in dairy cows, and the availability of AA is a function of the quantity of the metabolizable protein available and of hepatic AA catabolism. This study aimed to evaluate the effect of postruminal protein infusion on key genes for ureagenesis and AA catabolism. Six multiparous Holstein cows in early lactation were used in a replicated crossover design. Cows were fed a TMR and infused postruminally with either 0 or 600 g/d of milk protein isolate. Periods were 21 d long, consisting of 14 d of adjustment to surroundings, followed by 7 d of protein infusion. On the last day of each infusion, liver samples were collected for mRNA analysis and explant culture, milk samples were collected for mRNA analysis, and blood samples were collected for plasma metabolite analysis. Postruminal infusion of protein increased milk yield by 10.5%, milk fat yield by 12.5%, milk protein yield by 20%, milk lactose yield by 11%, and total solids yield by 15.5%. Postruminal infusion of protein increased milk urea N by 23.5%, blood urea N by 18.6%, and the abundance of hepatic ornithine transcarbamoylase mRNA by 52.8%. Postruminal infusion of protein did not alter the mRNA abundance of hepatic argininosuccinate synthase, α-aminoadipate semialdehyde synthase, cysteine sulfinic acid decarboxylase, or cystathionase. The abundance of RNA for milk proteins was unchanged with postruminal protein infusion. Metabolism of l -[U 14C] Lys to CO2 was increased by 127% (0.143 vs. 0.063 ± 0.04 nmol product·mg tissue−1·h−1), and the metabolism of l -[U 14C] Ala to CO2 increased by 40.5% (0.52 vs. 0.37 ± 0.06 nmol product·mg tissue−1·h−1) with postruminal protein infusion. The rate of l -[1-14C] Met oxidation did not differ. These data indicate increased ureagenesis matched by upregulation of nonessential AA catabolism and a disproportional increase in Lys oxidation in response to increased postruminal protein infusion.

This study's aim is to evaluate the substitution of soybean meal with a yeast-derived protein (YDP) in the diet of F1 Holstein (Bos Taurus) x Gyr (Bos indicus) dairy cows under rotational grazing (Guinea Grass, Panicum maximum cv. Mombaca) and to analyze the effects on milk yield, milk solids percentage, blood parameters, and feed efficiency (FE). Sixteen Holstein X Gyr (F1) multiparous cows with an average of 30 ± 1.8 kg/d (Mean ± SD) of milk, 489 ± 22 kg of body weight, and 62 ± 26 days in milk (DIM), at the beginning of the study, were assigned to four squares based on their DIM, milk yield, and parity. The experimental diets were based on the substitution of soybean meal with a YDP in equal proportions: treatment YDP0 (without a YDP), treatment YDP150 (substitution of 150 g of soybean meal with a YDP), treatment YDP300 (substitution of 300 g of soybean meal with a YDP), and treatment YDP450 (substitution of 450 g of soybean meal with a YDP). The substitution of soybean meal with a YDP in the diets of dairy cows under rotational grazing linearly decreased milk and solids production and affected the neutral detergent fiber (NDF) intake, without affecting the total feed intake. No difference was found in the microbial protein synthesis between treatments. FE tended to be lower at high inclusions of the YDP.

We aimed to determine the effects of partially replacing conventional solvent-extracted soybean meal by amino resin-treated soybean meal in the concentrate supplement of lactating dairy cows grazing Guinea grass (Panicum maximum cv. Mombaca) on dry matter intake, milk production and composition, feed and nitrogen use efficiency, and nutrient digestibility. Eighteen Holstein x Gyr crossbred multiparous cows (79 ± 38 days in milk and 37.4 ± 4.69 kg/d of milk yield) were used in a replicated 3 × 3 Latin square design study with three experimental periods of 21 d The solvent extract soybean meal of the control diet (CON) was replaced by 1.0 (TSBM1.0) and 1.5 (TSBM1.5) kg as-fed basis of amino resin-treated soybean meal (29 and 43% as dry-matter basis, respectively) in the treatment diets. Dry matter intake, milk casein, protein, and fat contents, feed efficiency, nitrogen use efficiency, and nutrient digestibility did not differ among treatments (P > 0.05). The metabolizable protein was not increased by the treatments; however, cows fed with TSBM1.5 tended to produce 1.2 kg/d more milk (P = 0.09) and 64.3 g/d more lactose (P = 0.06) than CON cows. Although the supply of metabolizable protein was not affected by treatments, increasing rumen undegradable protein supply by 43% by replacing conventional solvent-extracted soybean meal with amino resin-treated soybean meal tended to increase milk production of high producing grazing cows.

The objective for this study was to determine the effect of glucose dose and days following peak milk yield on plasma glucose, serum insulin, and plasma nonesterified fatty acids (NEFA) kinetics during an intravenous glucose tolerance test (IVGTT) in lactating dairy cattle. Six lactating Holstein dairy cows (3 primiparous and 3 multiparous) were assigned to 2 squares and received 0.092, 0.15, or 0.3 g of glucose/kg of body weight (BW) during an IVGTT at 74 and 221 d in milk (DIM), representing early (post-peak) lactation and mid lactation, respectively. Treatments were applied in a replicated Latin square design using contiguous 7-d periods within each stage of lactation. Milk production and dry matter intake were determined daily during the first 6 d of each period. The IVGTT was performed on d 7. For the IVGTT, cows were prepared with indwelling catheters in each jugular vein, and blood samples were collected at −15, −10, 5, 10, 15, 20, 30, 45, 60, 90, and 120 min relative to the glucose infusion. Samples were analyzed for plasma glucose, serum insulin, and plasma NEFA concentrations. Increasing the glucose dose during the IVGTT increased plasma glucose area under the curve (AUC), decreased glucose half-life, and increased maximal plasma glucose concentrations in plasma during the IVGTT. Greater glucose dose during the IVGTT elevated serum insulin AUC and increased nadir NEFA concentrations. Maximal plasma glucose concentration during the IVGTT was lower, whereas maximum NEFA concentration, NEFA AUC, and NEFA clearance rate were greater at 74 than at 221 DIM. Only glucose half-life was responsive to stage of lactation × glucose dose effects during the IVGTT, and the decrease in glucose half-life with increasing glucose dose was greater at 74 than at 221 DIM. Glucose AUC was greater and NEFA AUC lower for cows at 74 than at 221 DIM. For the doses tested, a glucose dose greater than 0.092 g/kg of BW resulted in peak blood glucose concentration that exceeded the previously reported renal glucose excretion threshold of 8.3 mM. There is a need for accompanying data to determine if this is the case for the glucose doses evaluated in this experiment. Based on maximal peak glucose concentrations and effects on glucose half-life, we identify 0.092 g of glucose/kg of BW (0.46 g/kg of metabolic body weight) as the preferred dose for the IVGTT for cows at 74 and 221 DIM in this study.

Introduction Meat consumption has been steadily increasing since the 1960s1. As living standards and income levels rise, more people include meat into their diet. Although an important source of nutrients, livestock production has a negative influence on greenhouse gas emissions, water consumption, water pollution, and more, with cattle being the main culprits2. However, while farming practices have improved over the last 60 years resulting in improved efficiencies in water, land, and crop use, studies suggest that cattle farmers can do more to reduce their overall environmental impact towards more sustainable production of animal protein3. The primary value of ruminants in the food chain is their ability to convert non-protein nitrogen, cellulose-rich carbohydrates, and other precursors to a digestible form of protein for human consumption. This is achieved through bacterial fermentation in the rumen that converts nitrogen (ammonia) to bacterial protein, which provides the animal with an essential protein supply to support growth and thereby meat and milk production for human consumption. Too little ammonia in the rumen limits bacterial protein synthesis. However, excess ammonia is converted to urea, which is excreted urine, and is an environmental burden. Excess nitrogen in manure is released to the atmosphere and is part of the issue with nitrogen runoff4. Our group is currently developing robotic technologies, termed RUMENS (Rumen Understanding through Millipede-Engineered Navigation and Sensing), to enable live, in vivo mapping of the ruminal environment, based on a suite of commercial and custom built sensors, of various compounds present in rumen5. Here, we propose a miniature, rapid update zinc oxide (ZnO) film-based sensor for real-time liquid ammonia detection in the rumen. Method Zinc acetate (ZnAc) and 2-methoxyethanol (2ME) were purchased from VWR, ethanolamine and ammonium hydroxide solution (28%) were purchased from Sigma Aldrich. All chemicals were used as received without any purification. Planar electrodes (inset of Figure 1), with dimensions of 1-mm-long and 2.54-mm-wide, were obtained from thermally evaporated Cr and Au on cleaned glass substrate, with the thicknesses of 3 nm and 50 nm, respectively. For ZnO layer deposition, 140 mg of ZnAc was dissolved in 1 mL of 2ME and 45 μL of ethanolamine at 60 °C for about 8 hours. The solution was spin cast at 600 rpm for 60 seconds. After manually patterning between two adjacent devices (to avoid crosstalk), the sample was then placed on a hot plate set to 300 °C in air for 10 minutes. After removal and cooling, the samples were rinsed consecutively in deionized H2O, acetone, ethanol, and IPA for 10 seconds each and then dried on a hotplate in air for 10 minutes at 200 °C6. An impedance measurement, using RLC meter (NF ZM 2372), was used to test the resistance with different ammonium concentrations. Ammonia of 10-1, 10-2, 10-3 and 10-4 M were prepared by diluting a known amount of ammonium hydroxide solution in DI water. A 3 μL of analyte was dropped onto the ZnO layer, directly between two planar gold electrodes. Devices were thoroughly (5 minutes) washed in DI water between measurements. Results and Conclusions Figure 1 shows the relationship between channel impedance (Z’) and concentration of ammonia at different scan frequencies, ranging from 1 to 100 kHz. The measurements reveal that at a fixed frequency, the impedance decreases with increased ammonia concentration. Also, at a single concentration, at low frequencies ( A possible sensing mechanism is the nitrification of NH4 + into nitrate ions, NO3 -, with nitrification reaction: NH4 + + 2O2 → NO3 - + H2O + 2H+. The energy released during oxidation should be sufficient for electrons to jump to the conduction band, resulting in decreasing of resistivity proportional to concentration of ammonia7. These results indicate a suitable device for aqueous ammonia detection in rumen. References Gerten, D.; Heck, V.; Jägermeyr, J.; Bodirsky, B. L.; Fetzer, I.; Jalava, M.; Kummu, M.; Lucht, W.; Rockström, J.; Schaphoff, S.; Schellnhuber, H. J., Feeding ten billion people is possible within four terrestrial planetary boundaries. Nature Sustainability 2020, 3 (3), 200-208. Gerber, P. J.; Steinfeld, H.; Henderson, B.; Mottet, A.; Opio, C.; Dijkman, J.; Falcucci, A.; Tempio, G. Tackling Climate Change Through Livestock - A Global Assessment of Emissions And Mitigation Opportunities; Food and Agriculture Organization of the United Nations: Rome, 2013. González, N.; Marquès, M.; Nadal, M.; Domingo, J. L., Meat consumption: Which are the current global risks? A review of recent (2010–2020) evidences. Food Research International 2020, 137, 109341. Schwab, C. G.; Broderick, G. A., A 100-Year Review: Protein and amino acid nutrition in dairy cows. Journal of Dairy Science 2017, 100 (12), 10094-10112. Balakuntala, M. V.; Ayad, M.; Voyles, R. M.; White, R.; Nawrocki, R.; Sundaram, S.; Priya, S.; Chiu, G.; Donkin, S.; Min, B.-C.; Daniels, K., Global Sustainability through Closed-Loop Precision Animal Agriculture. Mechanical Engineering 2018, 140 (06), S19-S23. Nawrocki, R. A.; Galiger, E. M.; Ostrowski, D. P.; Bailey, B. A.; Jiang, X.; Voyles, R. M.; Kopidakis, N.; Olson, D. C.; Shaheen, S. E., An inverted, organic WORM device based on PEDOT:PSS with very low turn-on voltage. Organic Electronics 2014, 15 (8), 1791-1798. Franco, F. F.; Manjakkal, L.; Shakthivel, D.; Dahiya, R. In ZnO based Screen Printed Aqueous Ammonia Sensor for Water Quality Monitoring, 2019 IEEE Sensors, 2019; pp 1-4. Fig 1. Impedance vs frequency of ammonia sensor as characterized for different concentrations. Figure 1