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1. Effects of monensin on glucose metabolism in transition dairy cows

Author:
Varga, G.A.,   et al.   ; Markantonatos, X.;     Show all 2 Author
Source:
Journal of dairy science 2017 v.100 no.11 pp. 9020-9035
ISSN:
0022-0302
Subject:
Holstein; blood glucose; computer software; dairy cows; diet; energy; experimental design; gluconeogenesis; glucose; jugular vein; models; monensin; oxidation; parturition; propionic acid; rumen; stable isotopes; tissues
Abstract:
... Eight multiparous periparturient Holstein cows fitted with ruminal cannula were used in a split plot design to evaluate the effects of monensin on plasma glucose metabolism. Diets were top-dressed daily with 0 mg/cow of monensin (control) or 300 mg/cow of monensin (MON) both pre- and postpartum. Plasma glucose kinetic parameters on d −13 ± 2.0 and 19 ± 1.6 relative to parturition were determined b ...
DOI:
10.3168/jds.2016-12007

2. Effect of dietary protein level and rumen-protected amino acid supplementation on amino acid utilization for milk protein in lactating dairy cows

Author:
Varga, G.A.,   et al.   ; Lee, C.; Giallongo, F.; Hristov, A.N.; Lapierre, H.; Cassidy, T.W.; Heyler, K.S.; Parys, C.;     Show all 8 Authors
Source:
Journal of dairy science 2015 v.98 no.3 pp. 1885-1902
ISSN:
0022-0302
Subject:
Holstein; adenosine monophosphate; amino acids; ammonia; blood plasma; cannulas; dairy cows; dairy protein; digestibility; excretion; milk composition; milk production; protein synthesis
Abstract:
... This study investigated the effect of metabolizable protein (MP) supply and rumen-protected (RP) Lys and Met supplementation on productivity, nutrient digestibility, urinary N losses, apparent total-tract digestibility of dietary AA, and the efficiency of AA utilization for milk protein synthesis in dairy cows. The experiment was conducted with 8 ruminally cannulated Holstein cows in a replicated ...
DOI:
10.3168/jds.2014-8496

3. Effect of Origanum vulgare L. leaves on rumen fermentation, production, and milk fatty acid composition in lactating dairy cows

Author:
Varga, G.A.,   et al.   ; Hristov, A.N.; Lee, C.; Cassidy, T.; Heyler, K.; Tekippe, J.A.; Corl, B.; Brandt, R.C.;     Show all 8 Authors
Source:
Journal of dairy science 2013 v.96 no.2 pp. 1189-1202
ISSN:
0022-0302
Subject:
Holstein; Origanum vulgare; ammonia; dairy cows; dietary supplements; digestibility; dry matter intake; experimental design; fatty acid composition; feed conversion; fungi; lactation; leaves; methane; methane production; methanogens; milk; milk composition; milk yield; neutral detergent fiber; nutrients; odors; oregano; pH; protein synthesis; rumen; rumen bacteria; rumen fermentation; urea nitrogen; urine; volatile fatty acids
Abstract:
... This experiment investigated the effects of dietary supplementation of Origanum vulgare L. leaf material (OR) on rumen fermentation, production, and milk fatty acid composition in dairy cows. The experimental design was a replicated 4×4 Latin square with 8 rumen-cannulated Holstein cows and 20-d experimental periods. Treatments were control (no OR supplementation), 250g/cow per day OR (LOR), 500g/ ...
DOI:
10.3168/jds.2012-5975
PubMed:
23245964

4. Effects of feeding dry propylene glycol to early postpartum Holstein dairy cows on production and blood parameters

Author:
Varga, G.A.,   et al.   ; Chung, Y.H.; Girard, I.D.;     Show all 3 Authors
Source:
Animal 2009 v.3 no.10 pp. 1368-1377
ISSN:
1751-7311
Subject:
dairy cows; Holstein; cow feeding; feed rations; postpartum period; temporal variation; feed additives; propylene glycol; dry matter intake; milk yield; milk composition; blood chemistry; insulin; metabolites; ketones; urine; ketosis; lactation
Abstract:
... In all, 18 multiparous and 19 primiparous Holstein dairy cows were used in a completely randomized design with restrictions to evaluate the effects of feeding propylene glycol (PG) as a dry product, via two delivery methods, on production and blood parameters. PG treatments were administered from parturition through 21 days postpartum. Treatments were: (i) control, no PG; (ii) top dress, 162.5 g P ...
DOI:
10.1017/S1751731109990292
PubMed:
22444931

5. Use of compartmental analysis to study ruminal volatile fatty acid metabolism under steady state conditions in Holstein heifers

Author:
Varga, G.A.,   et al.   ; Markantonatos, X.; Green, M.H.;     Show all 3 Authors
Source:
Animal feed science and technology 2008 v.143 no.1-4 pp. 70-88
ISSN:
0377-8401
Subject:
mathematical models; ruminant nutrition; volatile fatty acids; heifers; rumen; isotope labeling; butyrates; data analysis; Holstein; propionates; lipid metabolism
Abstract:
... Four rumen-cannulated Holstein heifers were used to quantify volatile fatty acid (VFA) kinetics in the rumen using ¹³C stable isotopes. Heifers were fed either a low (L) or high (H) concentrate diet with level of concentrate of 250 or 700g/kg dry matter, respectively. Isotopic tracers, Na-1-¹³C-acetate (Ac), -propionate (Pr), or -butyrate (Bu) were infused as a bolus into the rumen. Three days pri ...
DOI:
10.1016/j.anifeedsci.2007.05.005

6. Effects of metabolizable protein supply and amino acid supplementation on nitrogen utilization, milk production, and ammonia emissions from manure in dairy cows

Author:
Varga, G.A.,   et al.   ; Lee, C.; Hristov, A.N.; Heyler, K.S.; Cassidy, T.W.; Lapierre, H.; Parys, C.;     Show all 7 Authors
Source:
Journal of dairy science 2012 v.95 no.9 pp. 5253-5268
ISSN:
0022-0302
Subject:
Holstein; ammonia; corn; dairy cows; dairy manure; dairy protein; digestibility; dry matter intake; emissions; methionine; milk; milk fat percentage; milk protein yield; models; nitrogen; protein content; urea nitrogen
Abstract:
... Two experiments were conducted with the objective of investigating the effects of rumen-protected methionine (RPMet) supplementation of metabolizable protein (MP)-deficient or MP-adequate but Met-deficient diets on dairy cow performance. Experiment (Exp.) 1 utilized 36 Holstein dairy cows blocked in 12 blocks of 3 cows each. Cows within block were assigned to one of the following dietary treatment ...
DOI:
10.3168/jds.2012-5366
PubMed:
22916930

7. Effects of partially replacing dietary starch with dry glycerol in a lactating cow diet on ruminal fermentation during continuous culture

Author:
Varga, G.A.,   et al.   ; Rico, D.E.; Chung, Y.-H.; Martinez, C.M.; Cassidy, T.W.; Heyler, K.S.;     Show all 6 Authors
Source:
Journal of dairy science 2012 v.95 no.6 pp. 3310-3317
ISSN:
0022-0302
Subject:
acetates; bacterial proteins; cannulas; corn starch; cows; crude protein; digesta; digestibility; experimental diets; fermentation; fermenters; glycerol; lactation; neutral detergent fiber; propionic acid; protein synthesis; rumen fermentation; starch; total mixed rations
Abstract:
... The effects of dry glycerol as a partial replacement for dietary starch in a lactating cow diet on ruminal fermentation and bacterial protein synthesis were evaluated using 4 single-flow, continuous-culture fermentors (ranging from 1,015 to 1,040mL in volume). The basal lactating cow diet was formulated to have partial contents of dietary starch provided from a corn starch supplement [at 12.37% di ...
DOI:
10.3168/jds.2011-5059
PubMed:
22612964

8. Short communication: Interactions of milk, fat, and protein yield genotypes with herd feeding characteristics

Author:
Varga, G.A.,   et al.   ; Dekleva, M.W.; Dechow, C.D.; Daubert, J.M.; Liu, W.S.; Bauck, S.; Woodward, B.W.;     Show all 7 Authors
Source:
Journal of dairy science 2012 v.95 no.3 pp. 1559-1564
ISSN:
0022-0302
Subject:
Holstein; animal models; body condition; body weight; breeding value; cows; crude protein; diet; genetic correlation; genotype; herds; milk; nutrient intake; sires; Pennsylvania
Abstract:
... Data from 879 Holstein cows from 11 tie-stall herds in Pennsylvania were analyzed to determine the effects of nutritional management practices on the level of genetic expression for milk, fat, and protein yields. Environments were defined according to the amount of dry matter refusals at the end of 24h for the average cow (DMR), diet crude protein percentage (CP), and diet NEL concentration. Sire ...
DOI:
10.3168/jds.2011-4758
PubMed:
22365236

9. Effect of essential oils on ruminal fermentation and lactation performance of dairy cows

Author:
Varga, G.A.,   et al.   ; Tekippe, J.A.; Tacoma, R.; Hristov, A.N.; Lee, C.; Oh, J.; Heyler, K.S.; Cassidy, T.W.; Bravo, D.;     Show all 9 Authors
Source:
Journal of dairy science 2013 v.96 no.12 pp. 7892-7903
ISSN:
0022-0302
Subject:
Holstein; ammonia; blood plasma; cannulas; dairy cows; diet; digestibility; dry matter intake; essential oils; eugenol; excretion; feed conversion; gas emissions; lactation; lactose; methane; milk; milk fat; milk yield; neutral detergent fiber; nutrients; rumen; rumen fermentation; urea nitrogen; Switzerland
Abstract:
... Three experiments (Exp.) were conducted to study the effects of dietary addition of an essential oil product (EO) based on eugenol and cinnamaldehyde (0, control, or 525mg/d of Xtract 6965; Pancosma SA, Geneva, Switzerland) on ruminal fermentation, total-tract digestibility, manure gas emissions, N losses, and dairy cow performance. In Exp. 1 and 3, the EO supplement was added to the vitamin-miner ...
DOI:
10.3168/jds.2013-7128
PubMed:
24119814

10. Short communication: Feed utilization and its associations with fertility and productive life in 11 commercial Pennsylvania tie-stall herds

Author:
Varga, G.A.,   et al.   ; Vallimont, J.E.; Dechow, C.D.; Daubert, J.M.; Dekleva, M.W.; Blum, J.W.; Liu, W.; Heinrichs, A.J.; Baumrucker, C.R.;     Show all 9 Authors
Source:
Journal of dairy science 2013 v.96 no.2 pp. 1251-1254
ISSN:
0022-0302
Subject:
animal models; body condition; body weight; breeding value; cows; crude protein; days open; dry matter intake; feed conversion; genetic correlation; herds; lactation; milk; protein intake; sires; Pennsylvania
Abstract:
... The objectives of this study were to quantify the relationships of various definitions of feed utilization with both fertility and productive life. Intake and body measurement data were collected monthly on 970 cows in 11 tie-stall herds for 6 consecutive months. Measures of feed utilization for this study were dry matter intake (DMI), dry matter intake efficiency (DME, defined as 305-d fat-correc ...
DOI:
10.3168/jds.2012-5712
PubMed:
23219114
CHORUS:
10.3168/jds.2012-5712

11. Effects of monensin on volatile fatty acid metabolism in periparturient dairy cows using compartmental analysis

Author:
Varga, G.A.,   et al.   ; Markantonatos, X.; Aharoni, Y.; Richardson, L.F.;     Show all 4 Authors
Source:
Animal feed science and technology 2009 v.153 no.1-2 pp. 11-27
ISSN:
0377-8401
Subject:
isotope labeling; dietary energy sources; dietary carbohydrate; butyric acid; propionic acid; dietary supplements; dairy cows; volatile fatty acids; prepartum period; uptake mechanisms; animal performance; feed additives; nutrient utilization; pregnancy; rumen fermentation; postpartum period; lipid metabolism; monensin; acetic acid; kinetics
Abstract:
... Eight multiparous periparturient Holstein cows fitted with ruminal cannulas were used in a split plot design to evaluate effects of monensin on ruminal volatile fatty acid (VFA) metabolism. Diets were supplemented with 300mg/day of monensin, or no monensin, both prepartum and postpartum. Isotopic tracers, Na-1-¹³C-acetate (Ac), Na-1-¹³C-propionate (Pr), or Na-1-¹³C-butyrate (Bu) were used as marke ...
DOI:
10.1016/j.anifeedsci.2009.05.007

12. Rumen fermentation and production effects of Origanum vulgare L. leaves in lactating dairy cows

Author:
Varga, G.A.,   et al.   ; Tekippe, J.A.; Hristov, A.N.; Heyler, K.S.; Cassidy, T.W.; Zheljazkov, V.D.; Ferreira, J.F.S.; Karnati, S.K.;     Show all 8 Authors
Source:
Journal of dairy science 2011 v.94 no.10 pp. 5065-5079
ISSN:
0022-0302
Subject:
Holstein; Origanum vulgare; ammonia; ammonium nitrogen; cannulas; cross-over studies; dairy cows; dairy protein; digestibility; dry matter intake; energy; feed conversion; gas emissions; lactation; lactose; leaves; lipid content; metabolism; methane; methane production; milk; milk fat; milk yield; nutrients; oregano; pH; rumen; rumen fermentation; total mixed rations; urea nitrogen; volatile fatty acids
Abstract:
... A lactating cow trial was conducted to study the effects of dietary addition of oregano leaf material (Origanum vulgare L.; OV; 0, control vs. 500g/d) on ruminal fermentation, methane production, total tract digestibility, manure gas emissions, N metabolism, organoleptic characteristics of milk, and dairy cow performance. Eight primiparous and multiparous Holstein cows (6 of which were ruminally c ...
DOI:
10.3168/jds.2010-4095
PubMed:
21943758

13. Multiple-Chamber Instrumentation Development for Comparing Gas Fluxes from Biological Materials

Author:
Varga, G.A.,   et al.   ; Wheeler, E.F.; Topper, P.A.; Brandt, R.C.; Brown, N.E.; Adviento-Borbe, A.A.; Thomas, R.S.;     Show all 7 Authors
Source:
Applied engineering in agriculture 2011 v.27 no.6 pp. 1049-1060
ISSN:
0883-8542
Subject:
air; air flow; ammonia; computer software; dairy cows; dairy manure; data collection; feces; flowmeters; fluorescence; headspace analysis; hydrogen sulfide; instrumentation; monitoring; odors; olfactometry; urine
Abstract:
... The complex and often confounding factors that influence gas emission from biological materials require a measurement procedure that is precise, accurate, repeatable, and reliable. A multiple-chamber instrumentation system was developed to rapidly and precisely measure gas emission potential from multiple sources, such as manure and biosolids, to compare gas emission reduction potential of various ...

14. Rumen-protected lysine, methionine, and histidine increase milk protein yield in dairy cows fed a metabolizable protein-deficient diet

Author:
Varga, G.A.,   et al.   ; Lee, C.; Hristov, A.N.; Cassidy, T.W.; Heyler, K.S.; Lapierre, H.; de Veth, M.J.; Patton, R.A.; Parys, C.;     Show all 9 Authors
Source:
Journal of dairy science 2012 v.95 no.10 pp. 6042-6056
ISSN:
0022-0302
Subject:
alfalfa; corn; corn silage; crude protein; dairy cows; diet; digestibility; dry matter intake; essential amino acids; excretion; haylage; histidine; industry; lysine; methionine; milk; milk fat; milk protein yield; nutrients; secretion; true protein; urea nitrogen; Germany
Abstract:
... The objective of this experiment was to evaluate the effect of supplementing a metabolizable protein (MP)-deficient diet with rumen-protected (RP) Lys, Met, and specifically His on dairy cow performance. The experiment was conducted for 12wk with 48Holstein cows. Following a 2-wk covariate period, cows were blocked by DIM and milk yield and randomly assigned to 1 of 4 diets, based on corn silage a ...
DOI:
10.3168/jds.2012-5581
PubMed:
22863104

15. Effect on Production of Replacing Dietary Starch with Sucrose in Lactating Dairy Cows

Author:
Varga, G.A.,   et al.   ; Broderick, G.A.; Luchini, N.D.; Reynal, S.M.; Ishler, V.A.;     Show all 5 Authors
Source:
Journal of dairy science 2008 v.91 no.12 pp. 4801
ISSN:
0022-0302
Subject:
dairy cows; lactation; dietary carbohydrate; starch; sucrose; milk yield; cow feeding; alfalfa silage; lactation stage; dry matter intake; milk fat percentage; milk composition; ammonia; volatile fatty acids; urine; excretion; urea; nitrogen; intestinal microorganisms; microbial activity; rumen fermentation; nitrogen metabolism
Abstract:
... Replacing dietary starch with sugar has been reported to improve production in dairy cows. Two sets of 24 Holstein cows averaging 41 kg/d of milk were fed a covariate diet, blocked by days in milk, and randomly assigned in 2 phases to 4 groups of 6 cows each. Cows were fed experimental diets containing [dry matter (DM) basis]: 39% alfalfa silage, 21% corn silage, 21% rolled high-moisture shelled c ...
Handle:
10113/23477
DOI:
10.3168/jds.2008-1480
PubMed:
19038955

16. Heritability of Electronically Recorded Daily Body Weight and Correlations with Yield, Dry Matter Intake, and Body Condition Score

Author:
Varga, G.A.,   et al.   ; Toshniwal, J.K.; Dechow, C.D.; Cassell, B.G.; Appuhamy, J.A.D.R.N.;     Show all 5 Authors
Source:
Journal of dairy science 2008 v.91 no.8 pp. 3201-3210
ISSN:
0022-0302
Subject:
dairy cows; milk protein yield; temporal variation; body weight; body condition; genetic correlation; lactation; milk fat yield; heritability; dry matter intake; Pennsylvania; Virginia
Abstract:
... The objectives of this study were to estimate heritability for daily body weight (BW) and genetic correlations of daily BW with daily milk yield (MY), body condition score (BCS), dry matter intake, fat yield, and protein yield. The Afiweigh cow body weighing system records BW of every cow exiting the milking parlor. The Afiweigh system was installed at the Pennsylvania State University dairy herd ...
DOI:
10.3168/jds.2007-0627
PubMed:
18650298

17. Effects of Prepartum Dietary Carbohydrate Source and Monensin on Periparturient Metabolism and Lactation in Multiparous Cows

Author:
Varga, G.A.,   et al.   ; Chung, Y.-H.; Pickett, M.M.; Cassidy, T.W.;     Show all 4 Authors
Source:
Journal of dairy science 2008 v.91 no.7 pp. 2744-2758
ISSN:
0022-0302
Subject:
cow feeding; dietary carbohydrate; dairy cows; parity (reproduction); forage; prepartum period; soybean hulls; dietary fiber; blood lipids; body weight; calving; blood glucose; triacylglycerols; insulin; dry matter intake; monensin; milk yield; medicated feeds; milk composition; lactation; cottonseed hulls
Abstract:
... Eighty-five multiparous Holstein cows were used in a completely randomized design with restrictions to evaluate the effects of prepartum carbohydrate (CHO) source and monensin on periparturient dry matter intake (DMI), blood parameters, and lactation performance of dairy cows. Dietary treatments were arranged in a 2 x 2 factorial arrangement with a conventional (CONV) dry cow diet and a nonforage ...
DOI:
10.3168/jds.2007-0781
PubMed:
18565933

18. Ammonia and Greenhouse Gas Flux from Manure in Freestall Barn with Dairy Cows on Precision Fed Rations

Author:
Varga, G.A.,   et al.   ; Adviento-Borbe, M.A.A.; Wheeler, E.F.; Brown, N.E.; Topper, P.A.; Graves, R.E.; Ishler, V.A.;     Show all 7 Authors
Source:
Transactions of the ASABE 2010 v.53 no.4 pp. 1251-1266
ISSN:
2151-0032
Subject:
air; air temperature; alfalfa; ambient temperature; ammonia; barns; carbon dioxide; concrete; corn; correlation; crude protein; dairy cows; diet; drinking water; feces; free stalls; grasses; greenhouse gas emissions; greenhouse gases; hay; humidity; lactation; methane; microbial activity; nitrous oxide; particle size; silage; urine
Abstract:
... Two lactating cow trials were conducted to evaluate the impact of diets differing in silage source (alfalfa/maize vs. grass/maize or maize/hay) and maize grain particle size (fine vs. coarse) on ammonia (NH3), carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions from a freestall barn floor with two groups of 60 cows each. In addition, the effects of environment (temperature, humi ...

19. Effect of dietary carbohydrate and monensin on expression of gluconeogenic enzymes in liver of transition dairy cows

Author:
Varga, G.A.,   et al.   ; Karcher, E.L.; Pickett, M.M.; Donkin, S.S.;     Show all 4 Authors
Source:
Journal of animal science 2007 v.85 no.3 pp. 690-699
ISSN:
0021-8812
Subject:
cow feeding; gluconeogenesis; dietary carbohydrate; pyruvate carboxylase; dairy cows; gene expression; soybean hulls; dietary fiber; messenger RNA; calving; carboxy-lyases; rumen fermentation; dry matter intake; monensin; protein synthesis; liver; lactation; dosage; cottonseed hulls
Abstract:
... Thirty-four multiparous Holstein cows were used in a randomized block design to evaluate the effects of feeding nonforage fiber sources (NFFS), monensin, or their combination on expression of gluconeogenic enzymes in the liver during the transition to lactation. The addition of 0 or 300 mg/d of monensin to a conventional (CONV) or NFFS prepartum diet was evaluated in a 2 x 2 factorial arrangement ...
DOI:
10.2527/jas.2006-369
PubMed:
17296778

20. Short communication: Heritability of gross feed efficiency and associations with yield, intake, residual intake, body weight, and body condition score in 11 commercial Pennsylvania tie stalls

Author:
Varga, G.A.,   et al.   ; Vallimont, J.E.; Dechow, C.D.; Daubert, J.M.; Dekleva, M.W.; Blum, J.W.; Barlieb, C.M.; Liu, W.; Heinrichs, A.J.; Baumrucker, C.R.;     Show all 10 Authors
Source:
Journal of dairy science 2011 v.94 no.4 pp. 2108-2113
ISSN:
0022-0302
Subject:
animal models; body condition; body weight; cows; crude protein; dry matter intake; early lactation; economics; energy; feed conversion; herds; heritability; milk; somatic cells; tie stalls; true protein; urea nitrogen; Pennsylvania
Abstract:
... The objectives of this study were to calculate the heritability of feed efficiency and residual feed intake, and examine the relationships between feed efficiency and other traits of productive and economic importance. Intake and body measurement data were collected monthly on 970 cows in 11 tie-stall herds for 6 consecutive mo. Measures of efficiency for this study were: dry matter intake efficie ...
DOI:
10.3168/jds.2010-3888