The Utilization of Urea Nitrogen by Young Dairy Calves1

Brown, L.D.; Lassiter, C. A.; Everett, J.P.; Rust, J. W.

doi:10.2527/jas1956.1541125x

Cited by 20 publications

(8 citation statements)

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“…The finding that the digestibility of the diet declined as the level of crude protein was reduced, is in agreement with the results of Brown et al (1956);Brown, Lassiter, Everett, Seath and Rust (1958) and Whitelaw, Preston and Ndumbe (1961). The results also confirm the findings of Loosli and McCay (1943) and Brown et al (1956), that the digestibility coefficients of the various fractions were increased when urea was added to the diet to raise the level of crude protein.…”

Section: Discussionsupporting

confidence: 90%

“…The results also confirm the findings of Loosli and McCay (1943) and Brown et al (1956), that the digestibility coefficients of the various fractions were increased when urea was added to the diet to raise the level of crude protein. Although the low digestibility coefficients for crude fibre are comparable to values obtained by Stobo et al (1966) in calves given a high-protein concentrate diet, the slight, though non-significant, increase in digestibility of crude fibre that occurred when urea was added to the lowprotein concentrate, may reflect an increase in cellulose digestion, which has been shown to occur in vitro (Arias, Burroughs, Gerlaugh and Bethke, 1951) and in vivo (Brown et al, 1956). The observation that the digestibility of crude fibre remained considerably below the level found in calves given the high-protein concentrate, is in agreement with the findings of Brown et al (1956) and suggests that the concentration of non-structural carbohydrates was sufficiently high to prevent the urea from increasing cellulose digestion.…”

Section: Discussionsupporting

confidence: 88%

“…Although the low digestibility coefficients for crude fibre are comparable to values obtained by Stobo et al (1966) in calves given a high-protein concentrate diet, the slight, though non-significant, increase in digestibility of crude fibre that occurred when urea was added to the lowprotein concentrate, may reflect an increase in cellulose digestion, which has been shown to occur in vitro (Arias, Burroughs, Gerlaugh and Bethke, 1951) and in vivo (Brown et al, 1956). The observation that the digestibility of crude fibre remained considerably below the level found in calves given the high-protein concentrate, is in agreement with the findings of Brown et al (1956) and suggests that the concentration of non-structural carbohydrates was sufficiently high to prevent the urea from increasing cellulose digestion. Despite the lower value for apparent digestibility of dietary nitrogen in calves given the low-protein diet (treatment 18), the efficiency of utilisation of dietary nitrogen was significantly greater in these calves than in those given either of the other two diets.…”

Section: Discussionsupporting

confidence: 77%

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The protein requirement of the ruminant calf. III. The ability of the calf weaned at five weeks of age to utilise urea given as a supplement to a low-protein concentrate

Stobo¹,

Roy²,

Gaston³

1967

Anim. Sci.

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(1) Forty-five Ayrshire and Shorthorn bull calves were used in an experiment to study the ability of the calf weaned at 5 weeks on to concentrates, hay and water, to utilise urea added to a low-protein concentrate.(2) Calves given the concentrate containing 20% crude protein gained weight significantly faster from 3 to 12 weeks than those given concentrates containing either 12% crude protein, or 18% crude protein of which 33% was in the form of urea. There was a tendency for calves given the urea supplement to gain weight at a slightly faster rate to 8 weeks than those given the low-protein diet, but this tendency was reversed between 8 and 12 weeks of age.(3) At 15 weeks, the coefficients of apparent digestibility of dry matter, crude protein, crude fibre and nitrogen-free extract were significantly greater when an all-concentrate diet containing 19·6% crude protein was given, than with a concentrate containing 12·2% crude protein. When the lowprotein concentrate supplemented with urea was given (18·5% crude protein) the apparent digestibility of dry matter, crude protein and ether extract was significantly greater than on the low-protein concentrate. The digestibility of crude fibre in the urea-supplemented diet was intermediate between the values obtained on the high- and low-protein diets.(4) Despite marked differences between treatments in the intakes of apparently digested nitrogen, similar amounts of nitrogen were retained, because of large differences in the amounts of nitrogen excreted in the urine. However, the amount of nitrogen stored per unit of body-weight gain was 27% higher in calves given the concentrate containing 19·6% crude protein than in those given either the low-protein concentrate or the urea-supplemented diet.

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Section: Discussionsupporting

confidence: 90%

Section: Discussionsupporting

confidence: 88%

Section: Discussionsupporting

confidence: 77%

See 1 more Smart Citation

The protein requirement of the ruminant calf. III. The ability of the calf weaned at five weeks of age to utilise urea given as a supplement to a low-protein concentrate

Stobo¹,

Roy²,

Gaston³

1967

Anim. Sci.

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“…However, studies with milk replacer in dairy calves suggest that increasing protein increases calf BW and protein deposition, although protein may only be beneficial if energy supply is adequate (Bartlett et al, 2006). A portion of nitrogen requirements for nursing calves can be met by urea as early as 6 weeks of age (Brown et al, 1956), thus increased MUN in DDGS fed cows may have been responsible for increased growth rates of progeny. Changes in milk fat content and milk fatty acid composition may be responsible for enhanced calf growth as well.…”

Section: Milkmentioning

confidence: 99%

Feeding dried distillers grains with solubles to lactating beef cows: impact of excess protein and fat on cow performance, milk production and pre-weaning progeny growth

Shee

Lemenager

Schoonmaker

2016

Animal

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Multiparous Angus × Simmental cows (n = 54, 5.22 ± 2.51 years) with male progeny were fed one of two diets supplemented with either dried distillers grains with solubles (DDGS) or soybean meal (CON), from calving until day 129 postpartum (PP) to determine effects of excess protein and fat on cow performance, milk composition and calf growth. Diets were formulated to be isocaloric and consisted of rye hay and DDGS (19.4% CP; 8.76% fat), or corn silage, rye hay and soybean meal (11.7% CP; 2.06% fat). Cow-calf pairs were allotted by cow and calf age, BW and breed. Cow BW and body condition score (BCS; P ⩾ 0.13) were similar throughout the experiment. A weigh-suckle-weigh was performed on day 64 and day 110 ± 10 PP to determine milk production. Milk was collected on day 68 and day 116 ± 10 PP for analysis of milk components. Milk production was unaffected ( P ⩾ 0.75) by dietary treatments. Milk urea nitrogen was increased at both time points in DDGS compared with CON cows ( P < 0.01). Protein was decreased ( P = 0.01) and fat was increased ( P = 0.01) in milk from DDGS compared with CON cows on day 68 PP. Compared to CON, DDGS decreased medium chain FA ( P < 0.01) and increased long chain FA ( P < 0.01) at both time points. Saturated FA content of milk was decreased ( P < 0.01) at both time-points in DDGS compared with CON cows, which resulted in an increase ( P < 0.01) in monounsaturated and polyunsaturated FA, including cis-9, trans-11 conjugated linoleic acid. Daily gain of the DDGS calves was increased ( P = 0.01) compared with CON calves, resulting in heavier BW on day 129 ( P = 0.01). Heavier BW of DDGS calves was maintained through weaning ( P = 0.01). Timed-artificial insemination (TAI) rates were greater for cows fed DDGS compared with cows fed CON ( P < 0.02), but dietary treatment had no effect on overall pregnancy rates ( P = 0.64). In summary, feeding DDGS to lactating beef cows did not change cow BW or BCS, but did improve TAI rates and altered milk composition compared with CON. As a result, male progeny from cows fed DDGS during lactation had greater average daily gain and were heavier at day 129 and at weaning compared with male progeny from cows fed a control diet.

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“…This result is similar to that observed by BROWN et al6) In contrast, STOBO et al 7) has reported that the addition of urea to the low-protein diet did not result in increased daily nitrogen retention. This could probably be due to the fact that the level (about 12%) of pre-contained protein in the diet to which urea was added was too high to obtain a response with urea supplementation, as stated by STOBO et al7) Incidentally, this is about 9% in this experiment and about 7% in the study by BROWN et al 6) BROWN et al 6) found that calves fed with urea retained slightly less nitrogen than those fed with linseed meal, but that this difference was not significant. LEIBHOLZ and NAYNOR8) reported that daily nitrogen retention of calves on a diet supplemented with urea was equal to that of those on a diet supplemented with meat meal.…”

Section: Discussionmentioning

confidence: 52%