scholarly journals Untreated and formaldehyde-treated urea as nitrogen sources for lactating dairy cows

1982 ◽  
Vol 54 (1) ◽  
pp. 43-52
Author(s):  
Jouko Setälä ◽  
Liisa Syrjälä-Qvist

An experiment was performed with 22 Friesian cows, using a double reversal design with two treatments and one similar sequence for the two groups. The lengths of the standardization period, adaptation periods, test period and post-test period were 4, 1, 8 and 4 weeks, respectively. During the standardization and post-test periods the cows received pre-wilted grass silage ad libitum and a small amount of field-dried baled hay. In the test period hay was given ad libitum and the amount of grass silage was restricted. A concentrate mixture (barley, oats, minerals) was given daily to each cow at the rate of 0.3 kg/kg 4 % milk. During the standardization and post-test periods the mixture contained one percent of untreated urea and during the test period 2.5 % of untreated or treated urea. The urea had been treated with 1.5 % formaldehyde on a weight basis. The concentrate mixture was fed individually to each cow, but group feeding was used for the roughage. Among the cows producing more than 15 kg of 4 % milk a day, those receiving formaldehyde-treated urea had a significantly (P< 0.01) higher milk yield, and the fat content of their milk was significantly (P< 0.05) lower than the group receiving untreated urea. Among the cows producing less than 15kg of 4 % milk/day, the group given treated urea had a significantly (P

Author(s):  
K. Aston ◽  
W.J. Fisher ◽  
A.B. McAllan

Recent trials with cows fed grass silage have shown significant increases in intake and in yields of milk and milk solids when the crude protein (CP) concentration in a supplementary concentrate was raised. Giving additional CP in the concentrate was a more effective strategy for improving yields of milk and milk protein than giving extra energy (Aston et al 1992). The objective of this trial was to examine the influence of changes to the amount and pattern of distribution of CP supplied in a fixed concentrate ration given with grass silage ad libitum.Fifty-five Holstein-Friesian cows in their second and subsequent lactations were given a standard diet for two weeks from calving and then were used in a continuous feeding trial from weeks 4 to 21. The cows received 5 kg of fresh concentrate daily containing 156 (LP), 245 (MP) or 338 (HP) g CP per kg dry matter (DM), MP comprised equal amounts of LP and HP. Concentrate carbohydrate sources were cereals and digestible fibre and CP was increased by a mixture of 3:1 soya:fish meals. Grass silage contained 253 g toluene DM/kg, 162 g CP/kg DM, D value in vivo 0.723, pH 3.7, fermentation acids 135 g/kg DM of which 0.85 was lactic acid and NH3-N 91 g/kg total N.


Author(s):  
A Reeve ◽  
R D Baker ◽  
R G Hodson

There has been much recent debate about the protein requirements of lactatinq dairy cows, and this issue has been heightened by a general reduction in concentrate feeding in response to the imposition of milk quotas. Furthermore, the value of silage as a source of protein has been questioned widely. The objective of the present trial was to determine the effect of increasing supplementary protein on the performance of cows with ad libitum access to high quality grass silage.The trial, using January/February calving British Frieslan cows in second or subsequent lactations, was performed at Ravenscroft Hall Farm, Middlewich, Cheshire. Four groups of 15 cows were offered either 3 or 6 kg/head/day of cereal/soya/fishmeal based compound feeds containing either 214 (L) or 403 (H) g CP/kg DM, and high quality grass silage ad libitum.


Author(s):  
J.R. Newbold ◽  
B.R. Cottrill ◽  
R.M. Mansbridge ◽  
J.S. Blake

Few data are available to evaluate the Metabolisable Protein (MP) System (AFRC, 1992) as an aid to ration formulation for dairy cows. Responses of lactating dairy cows to MP were evaluated in two experiments.In Experiment One, groups of 10 Holstein cows were offered grass silage ad libitum and 7kg DM/d of one of six (treatments 1-6) compound foods from 39d after calving, for eight weeks. All rations were isoenergetic, assuming silage intake of 11kg DM/d (typical for the herd). Ratios between MP supply (calculated from in situ protein degradability measurements) and requirement (calculated for a standard cow: 565kg live weight, 281 milk/d, 40g/kg butterfat, 33g/kg milk protein, liveweight change =0kg/d) were 1.00, 1.02, 1.06, 1.06, 1.1 and 1.17 for treatments 1-6, respectively.


Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 961
Author(s):  
Ignacio E. Beltran ◽  
Pablo Gregorini ◽  
José Daza ◽  
Oscar A. Balocchi ◽  
Alvaro Morales ◽  
...  

The objective of this work was to evaluate whether changes in time of herbage allocation and herbage mass (HM) (low (L) or medium (M)) modify the diurnal pattern of urinary nitrogen (N) concentration and ruminal ammonia (NH3) of lactating dairy cows. Four Holstein-Friesian cows fitted with rumen cannula were randomly allocated to one of four treatments: 1) low herbage mass in the morning (L-AM) (Access to new herbage allocation after morning milking with a herbage mass (HM) of 2000 kg DM/ha); 2) low herbage mass in the afternoon (L-PM) (Access to new herbage allocation after afternoon milking with a HM of 2000 kg DM/ha); 3) medium herbage mass in the morning (M-AM) (Access to new herbage allocation after morning milking with a HM of 3000 kg DM/ha); and 4) medium herbage mass in the afternoon (M-PM) (Access to new herbage allocation after afternoon milking with a HM of 3000 kg DM/ha). A four by four Latin Square design with four treatments, four cows, and four experimental periods was used to evaluate treatment effects. Rumen NH3 concentration was greater for L-AM compared to L-PM and M-PM at 13:00 and 16:00 h. Urine urea and N concentrations were lower for M-AM compared to L-AM. Urine N concentration was greater for L-AM than other treatments at 10:00 hours and greater for M-PM compared to M-AM at 16:00 hours. Results suggest that maintaining the cows in the holding pen at the milking parlor for two hours after morning grass silage supplementation for L-AM and for two hours after afternoon grass silage supplementation for M-PM, could allow collection of urine from cows at the holding pen and storage of urine in the slurry pit during the time of peak N concentration, returning cows to the pasture at a time of day when urinary N concentration is decreased.


1960 ◽  
Vol 40 (2) ◽  
pp. 44-50 ◽  
Author(s):  
J. W. G. Nicholson ◽  
R. J. Curtis

Twenty Ayrshire and twenty Holstein-Friesian cows were used at the Experimental Farms, Charlottetown, Prince Edward Island, and Fredericton, New Brunswick, respectively, in an evaluation of the use of raw potatoes for feeding lactating dairy cows. The experiments were of the changeover design and were conducted in the period 1956–59. It was concluded that potatoes were equal to grass silage on a T.D.N. basis, provided that the protein content of the grain mixture fed with the potatoes was also increased. Better T.D.N. consumption was obtained when both silage and potatoes were fed than when silage was fed alone. Increasing the protein content of the grain mixture fed with potatoes resulted in increased production of F.C.M. and S.N.F., but not of butterfat.


Author(s):  
K. Aston ◽  
J.D. Sutton ◽  
R.D. Baker ◽  
W.J. Fisher

The response in yields of milk constituents to increases in the amounts of standard dairy concentrate (SC, 200 g crude protein (CP) per kg DM) given to cows consuming grass silage ad libitum were reported recently (Aston et al 1991; Baker et al 1991). A change of level however adjusts the supply of both energy and CP. Previous work also showed .linear responses in silage intake and milk and milk protein yields when CP was increased in a fixed ration of concentrate of constant energy value. In this trial energy and CP levels were varied Independently. The objective was to separate the effects of energy on the performance of lactating cows from those of CP.


1996 ◽  
Vol 1996 ◽  
pp. 85-85 ◽  
Author(s):  
R.J. Dewhurst ◽  
D.W.R. Davies ◽  
W.J. Fisher ◽  
K. Aston

Previous studies (Moorby et al, 1994) have shown increased yields of protein and lactose in the subsequent lactation as a consequence of feeding additional undegradable dietary protein (UDP) and restricting energy intake during the dry period. This experiment was undertaken to investigate the effect of supplementary UDP in the dry period diet of Holstein-Friesian cows given unrestricted access to grass silage and 1.5 kg of barley per day.Sixty-one cows received diets based on ad libitum access to grass silage with either (a) 1.5 kg barley / day or (b) 1.0 kg barley and 0.5 kg Maize Gluten Meal / day. After calving, cows had ad libitum access to grass silage (Metabolisable Energy (ME)=11.3 MJ/kg DM; crude protein (CP)=181 g/kg DM) and received 5 kg/day of concentrates (ME=13.0 MJ/kg DM; CP=250g/kg DM).


Author(s):  
J J Hyslop ◽  
D J Roberts

In a previous experiment outlined at last year's conference (Hyslop and Roberts, 1988), it was demonstrated that replacement of a proprietary pelleted concentrate with malt distillers grains (draff), should be limited to 15% of total dry matter intake (DMI) when draff is offered in two feeds per day. However there is little evidence to validate such a limitation when draff is used as a concentrate replacement in complete diets. This experiment examined the effect of replacing barley/soya with draff plus additional minerals in silage based complete diets.In a cyclic changeover design experiment consisting of 4 three week periods, fifteen British Friesian cows in early lactation were offered five treatments. Cows were given ad libitum access to one of five complete diets based on grass silage (69 “D”). Draff plus additional minerals gradually replaced barley/soya at increasing rates in diets 0-4 respectively.


Author(s):  
R.H. Phipps ◽  
J.D. Sutton ◽  
R.F. Weller

The “low milk fat” syndrome and “off feed” problems have long been associated with the use of rations incorporting a high proportion of starch based concentrate. These problems can be ameliorated by frequent feeding of concentrate, the use of out of parlour feeders or complete diets. Another approach has been to examine alternatives to cereal starch as the major energy source for concentrate supplements. Since few comparisons of concentrates containing a mixture of high quality fibre sources have been reported, the present trial was designed to compare concentrates based on cereal starch with those containing a mixture of high quality fibre sources when given with ad libitum grass silage from calving. An additional aim was to compare individual feeding through Calan Broadbent gates with groups fed forage at a self-feed clamp.


1996 ◽  
Vol 1996 ◽  
pp. 85-85
Author(s):  
R.J. Dewhurst ◽  
D.W.R. Davies ◽  
W.J. Fisher ◽  
K. Aston

Previous studies (Moorby et al, 1994) have shown increased yields of protein and lactose in the subsequent lactation as a consequence of feeding additional undegradable dietary protein (UDP) and restricting energy intake during the dry period. This experiment was undertaken to investigate the effect of supplementary UDP in the dry period diet of Holstein-Friesian cows given unrestricted access to grass silage and 1.5 kg of barley per day.Sixty-one cows received diets based on ad libitum access to grass silage with either (a) 1.5 kg barley / day or (b) 1.0 kg barley and 0.5 kg Maize Gluten Meal / day. After calving, cows had ad libitum access to grass silage (Metabolisable Energy (ME)=11.3 MJ/kg DM; crude protein (CP)=181 g/kg DM) and received 5 kg/day of concentrates (ME=13.0 MJ/kg DM; CP=250g/kg DM).


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