A meta-analysis of milk production responses to increased net energy intake in Scandinavian dairy cows

2015 ◽  
Vol 175 ◽  
pp. 59-69 ◽  
Author(s):  
Charlotte Jensen ◽  
Søren Østergaard ◽  
Ingunn Schei ◽  
Jan Bertilsson ◽  
Martin Riis Weisbjerg
Keyword(s):  
Dairy Cows ◽  
Energy Intake ◽  
Milk Production ◽  
Meta Analysis ◽  
Net Energy ◽  
Net Energy Intake

Meta-analysis on the effects of lipid supplementation on methane production in lactating dairy cows

2008 ◽  
Vol 88 (2) ◽  
pp. 331-337 ◽  
Author(s):  
M. Eugène ◽  
D. Massé ◽  
J. Chiquette ◽  
C. Benchaar
Keyword(s):  
Dairy Cows ◽  
Energy Intake ◽  
Milk Production ◽  
Meta Analysis ◽  
Milk Composition ◽  
Metabolizable Energy ◽  
Scientific Publications ◽  
Lactating Dairy Cows ◽  
Gross Energy ◽  
Lipid Supplementation

A meta-analysis was conducted to statistically determine the effects of lipid supplementation on methane (CH4) production, milk production, and milk composition of lactating dairy cows. For this purpose, a data base was built using seven scientific publications (25 diets) available in the literature and reporting the effects of lipid supplementation on CH4 production, milk production, and milk composition. Lipid supplementation decreased (P < 0.05) dry matter intake (DMI) by 6.4% compared with control diets, whereas production of milk and 4% FCM and milk composition were not changed (P > 0.05). Lipid supplementation decreased (P < 0.05) CH4 production by 9%, either expressed as MJ d-1 or as a percentage of gross energy intake (GEI), digestible energy intake (DEI), or metabolizable energy intake (MEI). This reduction was mainly a consequence of a decreased DMI. Key words: Meta-analysis, lipid supplementation, methane, dairy cows, lactating

Responses in live weight change to net energy intake in dairy cows

2015 ◽  
Vol 181 ◽  
pp. 163-170 ◽  
Author(s):  
Charlotte Jensen ◽  
Søren Østergaard ◽  
Jan Bertilsson ◽  
Martin Riis Weisbjerg
Keyword(s):  
Dairy Cows ◽  
Energy Intake ◽  
Weight Change ◽  
Live Weight ◽  
Net Energy ◽  
Net Energy Intake

EFFECTS OF CORRECTING FOR FEEDING LEVELS ON ESTIMATES OF GENETIC PARAMETERS OF MILK YIELD AND COMPOSITION

1976 ◽  
Vol 56 (3) ◽  
pp. 523-529 ◽  
Author(s):  
A. K. W. TONG ◽  
B. W. KENNEDY ◽  
J. E. MOXLEY
Keyword(s):  
Energy Intake ◽  
Milk Fat ◽  
Genetic Parameters ◽  
Genetic Relationships ◽  
Protein Yield ◽  
Net Energy ◽  
Yield Traits ◽  
Genetic And Phenotypic Correlations ◽  
Net Energy Intake ◽  
Quadratic Effects

A total of 13,561 Holstein 305-day lactation records were studied to examine the effects of correcting records for linear and quadratic effects of 305-day net energy intake from silage, hay, pasture and meal feeding on estimates of genetic parameters of milk, fat and protein yield and fat and protein percent. Correcting records for net energy intake reduced variances of yield traits, but had little effect on composition trait variances. When expressed as a percentage of the total variance, the relative importance of sire and sire–herd components were unchanged using corrected records, and heritabilities, except for that of protein yield, were unaltered. Cow components of yield traits were reduced relative to other components after records were corrected for feeding levels. Consequently, repeatabilities were reduced as well, suggesting that a large portion of the permanent environmental effects on yield traits may be of nutritional origin. Genetic and phenotypic correlations between yield traits were also reduced appreciably after records were corrected for feed intake. Genetic relationships between milk, fat and protein yield may not be as great as commonly believed.

Effect of timing of protein supplementation on the performance of lactating dairy cows

2005 ◽  
Vol 45 (4) ◽  
pp. 337
Author(s):  
B. C. Granzin
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Fat ◽  
Protein Supplementation ◽  
Net Energy ◽  
Maize Silage ◽  
Holstein Friesian ◽  
Grazing Dairy Cows ◽  
And Control ◽  
Friesian Cows

Two experiments were undertaken to determine the effect of timing of protein supplementation on performance of grazing, lactating Holstein–Friesian cows fed maize silage and grain-based concentrate. In experiment 1, 36 cows were fed 0.8 kg DM/day of solvent-extracted cottonseed meal (CSM) either as 1 meal at 1200 hours with maize silage (CSM 1200) or at 1530 hours with concentrate (CSM 1530), or in 2 meals at 0600 and 1530 hours with concentrate (CSM 600 + 1530). In experiment 2, 36 cows were either fed no CSM (control) or fed 1.0 kg DM/day as either CSM 1200 or CSM 600 + 1530. In experiment 1, daily yields of 4% fat-corrected milk (FCM) and milk fat for CSM 600 + 1530 were significantly higher than for CSM 1530 with respective means of 22.8 v. 20.7 L and 895 v. 804 g. Daily yields of FCM and milk fat for CSM 1200 were intermediate (21.7 L and 841 g/cow, respectively). A similar trend for daily protein yield per cow was noted (712, 695 and 666 g for CSM 600 + 1530, 1200 and 1530, respectively). In experiment 2, milk yield differed numerically between CSM 600 + 1530 and other treatments, with means (± s.e.d.) of 24.7 ± 0.78, 22.9 ± 0.78 and 22.9 ± 0.78 L/cow.day for CSM 600 + 1530, CSM 1200 and control, respectively. Mean (± s.e.d.) net energy requirements for milk production and liveweight change tended to be lower for the control (68 ± 3.6 MJ/cow.day) as opposed to CSM 600 + 1530 (79 ± 3.6 MJ/cow.day) and CSM 1200 (76 ± 3.6 MJ/cow.day). Cumulative time where rumen degradable nitrogen:rumen degradable dry matter was less than 22 g/kg were 2, 2 and 3 h for CSM 600 + 1530, CSM 1200 and CSM 1530, respectively, in experiment 1, and 6, 4 and 2 h for the control, 1200 and CSM 600 + 1530, respectively, in experiment 2. No differences in rumen ammonia-N concentrations were noted between treatments in experiment 1. In experiment 2, a significantly lower mean (± s.e.d.) rumen ammonia-N concentration was recorded for the control at 1530 hours (62 ± 14.1 mg/dL) in comparison to CSM 600 + 1530 (114 ± 14.1 mg/dL) and CSM 1200 (119 ± 14.1 mg/dL). These experiments show that for grazing dairy cows supplemented with maize silage and grain-based concentrate, feeding a daily aliquot of CSM as 2 meals at 0600 and 1530 hours rather than 1 meal at 1200 or 1530 hours improves milk production.

The effect of genetic merit and concentrate proportion in the diet on nutrient utilization by lactating dairy cows

1999 ◽  
Vol 132 (4) ◽  
pp. 483-490 ◽  
Author(s):  
C. P. FERRIS ◽  
F. J. GORDON ◽  
D. C. PATTERSON ◽  
M. G. PORTER ◽  
T. YAN
Keyword(s):  
Dairy Cows ◽  
Energy Intake ◽  
Milk Production ◽  
Milk Fat ◽  
Nutrient Utilization ◽  
Metabolizable Energy ◽  
Energy Utilization ◽  
Energy Output ◽  
Genetic Merit ◽  
Gross Energy

Sixty Holstein/Friesian dairy cows, 28 of high genetic merit and 32 of medium genetic merit, were used in a continuous design, 2 (cow genotypes)×4 (concentrate proportion in diet) factorial experiment. High and medium merit animals had Predicted Transmitting Abilities for milk fat plus protein yield, calculated using 1995 as the base year (PTA95 fat plus protein), of 43·3 kg and 1·0 kg respectively. Concentrate proportions in the diet were 0·37, 0·48, 0·59 and 0·70 of total dry matter (DM), with the remainder of the diet being grass silage. During this milk production trial, 24 of these animals, 12 from each genetic merit, representing three animals from each concentrate treatment, were subject to ration digestibility, and nitrogen and energy utilization studies. In addition, the efficiency of energy utilization during the milk production trial was calculated.There were no genotype×concentrate level interactions for any of the variables measured (P>0·05). Neither genetic merit nor concentrate proportion in the diet influenced the digestibility of either the DM or energy components of the ration (P>0·05). When expressed as a proportion of nitrogen intake, medium merit cows exhibited a higher urinary nitrogen output and a lower milk nitrogen output than the high merit cows. Methane energy output, when expressed as a proportion of gross energy intake, was higher for the medium than high merit cows (P<0·05), while urinary energy output tended to decrease with increasing proportion of concentrate in the diet (P<0·05). In the calorimetric studies, neither heat energy production, milk energy output and energy retained, when expressed as a proportion of metabolizable energy intake, nor the efficiency of lactation (kl), were affected by either cow genotype or concentrate proportion in the diet (P>0·05). However when kl was calculated using the production data from the milk production trial the high merit cows were found to have significantly higher kl values than the medium merit cows (0·64 v. 0·59, P<0·05) while k l tended to fall with increasing proportion of concentrate in the ration (P<0·05). However in view of the many assumptions which were used in these latter calculations, a cautious interpretation is required.

Position Choice by Drift-Feeding Salmonids: Model and Test for Arctic Grayling (Thymallus arcticus) in Subarctic Mountain Streams, Interior Alaska

1990 ◽  
Vol 47 (10) ◽  
pp. 2039-2048 ◽  
Author(s):  
Nicholas F. Hughes ◽  
Lawrence M. Dill
Keyword(s):  
Energy Intake ◽  
Water Depth ◽  
Focal Point ◽  
Water Velocity ◽  
Net Energy ◽  
Intake Rate ◽  
Arctic Grayling ◽  
Thymallus Arcticus ◽  
Net Energy Intake ◽  
Energy Intake Rate

We develop a model to predict position choice of drift-feeding stream salmonids, assuming a fish chooses the position that maximizes its net energy intake rate. The fish's habitat is represented as a series of stream cross-profiles, each divided into vertical strips characterized by water depth and velocity. The fish may select a focal point in any of these strips, and include several neighbouring strips in its foraging area. The number of prey the fish encounters depends on its reaction distance to prey, water depth, and water velocity; the proportion of detected prey the fish is able to capture declines with water velocity. The fish's net energy intake rate is its gross energy intake rate from feeding minus the swimming cost calculated by using water velocity at the fish's focal point. There was a close match between the positions predicted by this model and those chosen by solitary Arctic grayling (Thymallus arcticus) in the pools of a mountain stream in Alaska.

scholarly journals Alfalfa Protein Concentrate as a Less Ruminally Degradable Protein Source for High-Producing Dairy Cows

1997 ◽  
Vol 2 ◽  
pp. 31
Author(s):  
C.D. Lu ◽  
NA. Jorgensen
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Crude Protein ◽  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Ammonia Nitrogen ◽  
Neutral Detergent Fiber ◽  
Net Energy ◽  
Protein Concentrate ◽  
Dietary Nitrogen

Ten multiparous Holstein cows were used in a 105-day continuous feeding trial to compare soybean meal (SBM) and alfalfa protein concentrate (APC) as supplemental protein sources for high-producing dairy cows. Dairy cows with an average milk production of 35.2 kg/day were paired and randomly assigned to one of the treatments. A double reversal design was employed With 35 days per period. The comparison between treatments was made during the last 21 days of each period. Experimental diets, containing 60% corn silage and 10% alfalfa hay, were formulated to be isonitrogenous and isoenergetic (crude protein. 15.6%; net energy tor lactation, 1.60 Mcal/kg DM). Fifty percent of dietary nitrogen was provided by test proteins. Animals were fed four times daily. Chromie oxide boluses, 50 g/day were used to estimate digestion coefficients. Ruminal protein degradability in viva (%) and in situ(%)were 56.8, 68.3 and 47.3. 35.3 for SBM and APC, respectively. Dry matter intake (kg/day) was 19.1 and 18.6 for cows fed SBM and APC. respectively. Rummal parameters cows fed SBM vs APC were, pH. 6.6 vs 6.7, ammonia nitrogen(mg/dI) 10.8 vs 6.2(p less than 0.01); total volatile fatty acids (mM), 86.3 VS 84.6(P LESS THAN 0.05), acetate (%) , 50.8 vs 64.9 (p less than 0.01); propionate dry matter , 65.3 vs 61.8; crude protein . 67.6 vs 61.1 (P less than 0.05 ) neutral detergent fiber , 51.1 vs 52.5 ; acid detergent fiber, 47.7 vs 49.0 . A slightly higher (P more than 0.05 ) amount of milk was produced by cows fed APC(28.6+_ 3.5 vs 28.2+- 3.8 kg/day). Each additional gramof undergradable intake protein provided by APC continued to a 5- gram increase in 4% fat-corrected milk production.

scholarly journals Description and evaluation of a net energy intake model as a function of dietary chewing index

2016 ◽  
Vol 99 (11) ◽  
pp. 8699-8715 ◽  
Author(s):  
L.M. Jensen ◽  
B. Markussen ◽  
N.I. Nielsen ◽  
E. Nadeau ◽  
M.R. Weisbjerg ◽  
...  
Keyword(s):  
Energy Intake ◽  
Net Energy ◽  
Net Energy Intake
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