The nutrition of ruminants grazing native and improved pastures. II.* Responses of grazing cattle to molasses and urea supplementation

1978 ◽  
Vol 29 (4) ◽  
pp. 875 ◽  
Author(s):  
JP Langlands ◽  
GE Donald
Keyword(s):  
White Clover ◽  
Cattle Grazing ◽  
Ammonia Nitrogen ◽  
Curvilinear Relationship ◽  
Nitrogen Levels ◽  
Grazing Cattle ◽  
Native Pasture ◽  
Digestible Organic Matter ◽  
Ad Libitum ◽  
Rumen Ammonia Nitrogen

Hereford heifers grazing native and fertilized phalaris pastures were supplemented with ureamolasses mixtures for 2 years. The liveweight of heifers grazing phalaris pastures did not respond to supplementation, but the liveweight gain of heifers grazing native pasture increased significantly by 6 g/day/g nitrogen consumed as urea during July, August and September and by 0.16 g/day/g digestible organic matter consumed as molasses at other times of year. Supplement consumption varied between animals, with a coefficient of variation of ±37%. Urea–molasses supplementation increased the rumen ammonia nitrogen levels of cattle grazing native pasture from 6.7 to 16.1 mg/100 ml. The application of superphosphate and introduction of white clover increased rumen ammonia nitrogen to 15.7 mg/100 ml. The effects of supplementation on liveweight gain were small relative to the changes which could be induced by pasture improvement. There was a curvilinear relationship between the digestibility of the diet and liveweight gain when pasture availability was not limiting intake. It was calculated from this relationship that the annual liveweight gains of cattle grazing native pasture, native pasture dressed with superphosphate and oversown with white clover, and two phalaris pastures were 223 498, 726 and 763 g/day respectively when forage was available ad libitum. ____________________ *Part I, Aust. J. Agric. Res., 29: 863 (1978).

Corrigendum - The effect of formaldehyde treatment of a casein supplement on urea excretion and on digesta composition in sheep

1974 ◽  
Vol 25 (4) ◽  
pp. 599
Author(s):  
GJ Faichney
Keyword(s):  
Nitrogen Retention ◽  
Ammonia Nitrogen ◽  
Nitrogen Excretion ◽  
Plasma Urea ◽  
Urea Excretion ◽  
Nitrogen Levels ◽  
Formaldehyde Treatment ◽  
The Relationship ◽  
Filtered Load ◽  
Rumen Ammonia Nitrogen

The urinary excretion of urea, the fate of an intravenous dose of urea, overall nitrogen metabolism and the composition of rurnen and abomasal samples were studied in crossbred sheep given a basal roughage diet to which supplements of starch, casein or formaldehyde-treated casein were added. Urea excretion was closely related to plasma urea level (r = 0.935) and to the filtered load of urea (r = 0.957). The amount of urea reabsorbed by the kidney increased as'the amount filtered increased; the relationship was improved when values obtained at urine flow rates less than 1 rnl/rnin were omitted. When sheep were given the starch and treated casein diets, the rate at which they cleared a small dose of urea from their plasma was greater than the renal clearance rate; only 75% of a large dose was recovered in the urine. The capacity to dispose of exogenous urea by extra-renal pathways was apparent only when rumen ammonia nitrogen levels were less than about 200 mg/l. Formaldehyde treatment reduced nitrogen digestibility but reduced urine nitrogen excretion to a greater extent so that nitrogen retention increased. Treatment was associated with reduced plasma urea levels, reduced rumen and abomasal ammonia levels, reduced total VFA levels, increased proportions of acetic acid and decreased proportions of isobutyric, isovaleric and n-valeric acids, and more protein in abomasal contents.

The effect of formaldehyde treatment of a casein supplement on urea excretion and on digesta composition in sheep

1974 ◽  
Vol 25 (4) ◽  
pp. 599
Author(s):  
GJ Faichney
Keyword(s):  
Nitrogen Retention ◽  
Ammonia Nitrogen ◽  
Nitrogen Excretion ◽  
Plasma Urea ◽  
Urea Excretion ◽  
Nitrogen Levels ◽  
Formaldehyde Treatment ◽  
The Relationship ◽  
Filtered Load ◽  
Rumen Ammonia Nitrogen

The urinary excretion of urea, the fate of an intravenous dose of urea, overall nitrogen metabolism and the composition of rurnen and abomasal samples were studied in crossbred sheep given a basal roughage diet to which supplements of starch, casein or formaldehyde-treated casein were added. Urea excretion was closely related to plasma urea level (r = 0.935) and to the filtered load of urea (r = 0.957). The amount of urea reabsorbed by the kidney increased as'the amount filtered increased; the relationship was improved when values obtained at urine flow rates less than 1 rnl/rnin were omitted. When sheep were given the starch and treated casein diets, the rate at which they cleared a small dose of urea from their plasma was greater than the renal clearance rate; only 75% of a large dose was recovered in the urine. The capacity to dispose of exogenous urea by extra-renal pathways was apparent only when rumen ammonia nitrogen levels were less than about 200 mg/l. Formaldehyde treatment reduced nitrogen digestibility but reduced urine nitrogen excretion to a greater extent so that nitrogen retention increased. Treatment was associated with reduced plasma urea levels, reduced rumen and abomasal ammonia levels, reduced total VFA levels, increased proportions of acetic acid and decreased proportions of isobutyric, isovaleric and n-valeric acids, and more protein in abomasal contents.

Liveweight response following sodium chloride supplementation of beef cows and their calves grazing native pasture

1973 ◽  
Vol 13 (63) ◽  
pp. 369 ◽  
Author(s):  
GM Murphy ◽  
AW Plasto
Keyword(s):  
Sodium Chloride ◽  
Cattle Grazing ◽  
Beef Cows ◽  
Common Salt ◽  
Hereford Cattle ◽  
Native Pasture ◽  
Urinary Levels ◽  
Ad Libitum ◽  
Native Pastures

Hereford cattle grazing native pastures on the eastern Darling Downs, Queensland, were deemed sodium (Na) deficient on the basis of salivary Na and potassium (K) levels. Common salt (NaCl) was offered ad libitum to one half of the animals. Cows receiving the supplement had significantly better rates of liveweight increase (0.35 v. 0.14 kg head-1 day-1, P < 0.01) than unsupplemented cows. Calves of supplemented cows grew significantly faster than calves of unsupplemented cows (0.77 v. 0.62 kg head-1 day-1, P < 0.01). After 21 days of Na supplementation, cows in the supplemented group had mean saliva values of 139.1 m-equiv l-1 Na and 7.4 m-equiv l-1 K; these values are considered normal. Corresponding values in the unsupplemented group were 60.2 m-equiv l-1 Na and 71.7 m-equiv l-1 K, which are indicative of severe Na deficiency. Levels of this magnitude remained throughout the duration of the experiment. Blood and milk concentrations of Na and K were not affected by Na intake. Urinary levels of Na and K were attered by Na intake but were extremely variable.

The nutrition of ruminants grazing native and improved pastures. III.* Mineral composition of bones and selected organs from grazing cattle

1978 ◽  
Vol 29 (6) ◽  
pp. 1301 ◽  
Author(s):  
JP Langlands ◽  
RDH Cohen
Keyword(s):  
White Clover ◽  
Dry Matter ◽  
Soft Tissues ◽  
Long Bones ◽  
Selenium Content ◽  
Grazing Cattle ◽  
Native Pasture ◽  
Calcium Phosphorus ◽  
Liver And Kidney ◽  
Copper Zinc

Hereford heifers grazed native pasture, native pasture which had been dressed with superphosphate, native pasture which had been dressed with superphosphate and oversown with white clover and native pasture which had been dressed with superphosphate and oversown with white clover and lotononis. The heifers were slaughtered after 12 months and the livers and kidneys were analysed for copper, zinc, molybdenum and manganese, the hearts for copper, zinc and manganese, and the livers for selenium. Samples of the spine, skull and tail, ribs, pelvis and scapula, long bones and soft tissues were analysed separately for nitrogen, fat, ash, calcium, phosphorus, magnesium, zinc and sodium. There were significant increases in the copper, zinc, and manganese contents of the kidneys when pastures were improved, but these differences were not evident in the liver or heart or in the molybdenum contents of the liver and kidney. Selenium content of the liver declined. The concentrations of phosphorus, calcium and magnesium in the fat-free dry matter of the spine, skull and tail, and ribs were less for cattle grazing native than for those grazing the other pastures. Differences in the composition of the pelvis and scapula, and long bones were not significant. _________________ *Part 11, Aust. J. Agric. Res., 29: 875 (1978).

The feed intake of grazing cattle. II. The influence of size of animal on feed intake

1961 ◽  
Vol 3 (03) ◽  
pp. 251-260 ◽  
Author(s):  
W. Holmes ◽  
J. G. W. Jones ◽  
R. M. Drake-Brockman
Keyword(s):  
Organic Matter ◽  
White Clover ◽  
Feed Intake ◽  
Live Weight ◽  
Chromic Oxide ◽  
Grazing Cattle ◽  
Continuous Grazing ◽  
Digestible Organic Matter ◽  
Faecal Nitrogen

1. Two experiments each with 3 dry cows, 3 heifers and 3 calves were carried out in 1959 and 1960 under uniform continuous grazing conditions on a ryegrass-white clover sward to measure individual feed intake by the chromic oxide-faecal nitrogen method.2. Estimates of digestibility were high (70–82% in organic matter) and there was evidence that calves selected a diet of higher digestibility than cows.3. Mean daily estimates of organic matter intake were for cows (1300 lb. live-weight) 23·5 lb., for heifers (790 lb. live-weight) 20·8 lb. and for calves (450 lb. live-weight) 14·3 lb. Corresponding digestible organic matter intakes were 17·4, 15·3 and 11·0 lb.4. Relationships between digestible organic matter intake and liveweight were calculated and the merits of the exponents 0·62 and 0·73 of liveweight discussed.5. The results were compared with accepted cow equivalent standards and, regardless of the exponent chosen, agreed with the system which adopts higher values for young grazing cattle.

UTILIZATION OF ENSILED OR ACID-TREATED HIGH-MOISTURE SHELLED CORN BY CATTLE

1973 ◽  
Vol 53 (3) ◽  
pp. 491-496 ◽  
Author(s):  
D. R. McKNIGHT ◽  
G. K. MACLEOD ◽  
J. G. BUCHANAN-SMITH ◽  
D. N. MOWAT
Keyword(s):  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Rumen Fluid ◽  
Latin Square ◽  
Ammonia Nitrogen ◽  
Starch Digestibility ◽  
High Moisture ◽  
Nitrogen Levels ◽  
Matter Basis ◽  
Rumen Ammonia Nitrogen

Shelled corn of approximately 25% moisture was artificially dried (DC), ensiled (HMEC), or preserved either with 1.25% of a 60:40 mixture of acetic and propionic acids (HMAP) or with 1.00% propionic acid (HMP), and was examined for chemical and physical differences. Diets consisting of 66% corn (dry matter basis) were fed in a 4 × 4 latin square arrangement of treatments to four rumen and abomasal fistulated yearling heifers. High-moisture (HM) corn diets were more (P < 0.05) digestible in dry matter (77.4 vs. 74.2%) and energy (75.4 vs. 72.4%) than was the DC diet. Acid-treated corn diets had higher (P < 0.05) starch digestibility (95.6 vs. 91.7%) than DC diets. HMP diet was superior (P < 0.05) in starch digestibility to HMEC and significantly (P < 0.05) higher in nitrogen digestibility than was DC. Rumen ammonia nitrogen levels were higher (P < 0.05) on HMEC than on HMAP diet. Significantly (P < 0.05) higher total quantities of propionic and butyric acids in rumen fluid were observed on HMP diet and the quantity of total rumen volatile fatty acids tended to be higher on HMP than on other diets. Results suggest that HM corn diets move through the reticulorumen more slowly and experience greater digestion in this area than does DC diet.

The development of rumen function in the lamb.

1961 ◽  
Vol 12 (4) ◽  
pp. 661 ◽  
Author(s):  
ID Wardrop ◽  
JB Coombe
Keyword(s):  
Crude Protein ◽  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Ammonia Nitrogen ◽  
Dry Matter Intake ◽  
Crude Fibre ◽  
Rumen Development ◽  
Series Of Experiments ◽  
Ad Libitum ◽  
Rumen Ammonia Nitrogen

A series of experiments is presented, describing the development of the rumen function in grazing lambs and the effects of' diet on the rumen development of artificially reared lambs. In grazing lambs the volume of the abomasum contents showed little change with age. The volume of the rumen contents increased with age, and the rate of' this increase was most marked from 3 weeks of age onwards. The volume of the rumen contents, relative to both the liveweight and the volume of the abomasum contents, was constant from 8 weeks of age onwards. The rumen volatile fatty acids (V.F.A.) concentrations in grazing lambs increased from birth and reached adult levels at 8 weeks of age. The total quantity of V.F.A. present in the rumen at a given time, relative to liveweight, increased up to 8 weeks of age but from this age onwards was approximately constant. The rumen ammonia nitrogen (N) concentrations in grazing lambs were high for the first few weeks after birth, but showed a continuous fall, reaching adult levels at 5 weeks of age. The quantity of ammonia N present in the rumen at a given time, relative to liveweight, increased up to 8 weeks of age and then remained approximately constant. The rumen volumes, V.F.A., and ammonia N concentrations were normal only in lambs that had been fed roughage. When lucerne chaff was fed to young lambs, the digestibilities of the dry matter, crude protein, and crude fibre were high, irrespective of whether the previous diet had been milk or chaff. The ad libitum dry matter intake from roughage, relative to the liveweight, increased up to 8 weeks of age and then remained approximately constant. When roughage was fed to lambs which had been reared on 'milk' (a preparation from dried cows' milk) only from birth to 9 weeks of age, the rumen V.F.A. concentrations rose immediately and levelled off at adult levels within 1 week.

Some experimental observation on the toxicity of urea to sheep

1960 ◽  
Vol 11 (2) ◽  
pp. 247 ◽  
Author(s):  
JB Coombe ◽  
DE Tribe ◽  
JWC Morrison
Keyword(s):  
Experimental Observation ◽  
Daily Intake ◽  
Ammonia Nitrogen ◽  
Theoretical Explanation ◽  
Nitrogen Levels ◽  
Rumen Ph ◽  
Ammonia Absorption ◽  
Ph Level ◽  
Rumen Ammonia Nitrogen

The rumen pH and ammonia nitrogen levels were recorded in sheep fed on different amounts of urea in different ways. It was found that when the urea was sprayed onto the daily intake of roughage these levels remained low, even when intakes of 100 g urea were obtained, compared with the levels recorded when lower levels of urea (25 g) were given as a drench. As the rumen pH level rose to 7.0 and above, the periods of time spent ruminating declined until at about a pH of 7.3 complete rumen stasis occurred. The stasis did not occur at higher levels of rumen ammonia nitrogen provided that the pH level was kept down. Sheep readily consumed large amounts (up to 100 g) of urea per day provided that the concentration of urea in the ration did not exceed 6 per cent.; when this happened the food intakes were markedly reduced. A theoretical explanation is offered of the influence of the rumen pH level on the rate of ammonia absorption from the rumen.

Effect of intraruminal infusion of urea on the response in voluntary food intake by sheep

1985 ◽  
Vol 36 (3) ◽  
pp. 483 ◽  
Author(s):  
JK Egan ◽  
PT Doyle
Keyword(s):  
Organic Matter ◽  
Food Intake ◽  
Dry Matter ◽  
Block Design ◽  
Ammonia Nitrogen ◽  
Dry Matter Intake ◽  
Plant Cell Walls ◽  
Randomized Block Design ◽  
Ad Libitum ◽  
Ad Libitum Intake

Six mature Merino sheep received three treatments in a randomized block design experiment. The treatments were: chopped oaten hay diet at 90% of ad libitum intake without urea (L); the ciet offered at the same level as for L with urea infused into the rumen at 11.5 g kg-1 dry matter intake (LU); and the diet offered at 90% of the ad libitum intake achieved with urea infused at 11.5 g kg-1 dry matter intake (HU). Sheep given HU consumed 37% more (P < 0.01) organic matter (OM) than those fed L or LU, but the apparent digestibility of OM did not vary (59.2-61.8%) between treatments. The addit onal food consumption was associated with c. 20% increase (P < 0.05) in the weight of OM in the reticulorumen and significantly higher (by 10-35%; P < 0.05) fractional outflow rates of most dietary and microbial constituents of digesta. The fractional digestion rate of potentially digestible plant cell walls was not affected by urea, but the flow of microbial non-ammonia nitrogen from the abomasum was enhanced (L, 7.0; LU, 8.2; HU, 12.5 g day-1; P < 0.05). The results of this study suggest that the stimulatory effect of urea upon food intake was associated with the provision of additional microbial protein for digestion in the intestines, rather than changes in the rate or extent of organic matter fermentation in the reticulorumen.

Milk production from diets of silage and dried forage. 1. Effects of methods of processing dried grass and of including barley in the supplementation of grass silage given ad libitum

1976 ◽  
Vol 23 (2) ◽  
pp. 197-209 ◽  
Author(s):  
J. C. Tayler ◽  
K. Aston
Keyword(s):  
Energy Content ◽  
Live Weight ◽  
Experimental Period ◽  
Milk Composition ◽  
Weight Changes ◽  
Treatment Groups ◽  
Grass Silage ◽  
Digestible Organic Matter ◽  
Ad Libitum ◽  
Female Cattle

SUMMARY1. Young adult and adult British Friesian female cattle (heifers and cows) which were lactating were individually fed on diets of grass silage ad libitum with supplements of dried grass, dried grass/barley or barley/groundnut in two randomized block experiments.2. In Experiment I, equal quantities of dry matter (DM) as dried grass in the form of a wafer (W), cob (C) or pellet (P) were given with the silage during weeks 8 to 18 of lactation, to three groups of 12 heifers. Silage DM intakes were respectively 14·2, 14·3 and 15·8 ± 0·43 g/kg live weight per day (P<0·05). Milk yields were 14·0, 15·6, 16·7 ± 0·35 kg/day (P< 0·001). Milk composition and live-weight change did not differ significantly.3. In Experiment II, five treatment groups of heifers and cows were offered silage with equal amounts of a supplement of either dried grass pellets (treatment 1) or dried grass/barley in the ratios of 2: 1 (treatment 2), 1: 2 (treatment 3), or a barley/groundnut supplement (treatment 4). In treatment 5 the cattle received the same supplement as in treatment 4, but at a 10% higher level. Silage DM intakes for treatments 1 to 5 during lactation weeks 6 to 22 were 8·64, 8·94, 7·96, 6·96, 7·63 kg/day (1, 2>4, P<0·01; 2>5, P<0·05). The intake of digestible organic matter, milk yields and live-weight changes over the whole experimental period were not influenced significantly by treatments 1 to 4, but in treatment 5 the milk was significantly higher in fat, protein and energy content than in treatments 1 to 4. Blood composition was normal and did not differ markedly between treatments.

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