MEASUREMENT OF DUODENAL FLOW IN DAIRY COWS BY EITHER TOTAL COLLECTION OR SPOT SAMPLING, USING A SPECIAL CANNULA

1984 ◽  
Vol 64 (5) ◽  
pp. 116-117 ◽  
Author(s):  
K. ROHR ◽  
M. BRANDT ◽  
P. LEBZIEN ◽  
H. SCHAFFT
Keyword(s):  
Organic Matter ◽  
Dairy Cows ◽  
Key Words ◽  
Dry Matter ◽  
Sampling Technique ◽  
Sampling Procedure ◽  
Single Marker ◽  
The Mean ◽  
Special Cannula ◽  
Friesian Cows

Duodenal flow as derived from total collection and spot sampling was compared in three Friesian cows, using a re-entrant cannula without transecting the intestine. Cr2O3 was used as a single marker. Small differences in flow of dry matter, organic matter and nitrogen indicate that the spot sampling procedure may render valid results. The mean recovery of Cr2O3 was 96.7%. Key words: Cattle, duodenal flow, sampling technique, marker

Evaluation of techniques for estimating the yield of irrigated pastures intensively grazed by dairy cows. 1. Visual assessment

1984 ◽  
Vol 24 (126) ◽  
pp. 300 ◽  
Author(s):  
CR Stockdale
Keyword(s):  
Dairy Cows ◽  
Dairy Cow ◽  
Dry Matter ◽  
Sampling Technique ◽  
Visual Assessment ◽  
Sampling Procedure ◽  
Double Sampling ◽  
Assessment Technique ◽  
Coefficients Of Variation ◽  
The Mean

A visual assessment technique was evaluated for estimating pre- and post-grazing pasture yields in experiments in which dairy cows rotationally graze irrigated pastures. Visual assessment, when associated with the harvesting of standard quadrats, accounted for 62.3 and 68.4% of the variability in pre- and post-grazing yield, respectively. The mean residual standard deviations associated with the pre- and post-grazing regressions were 490 and 395 kg dry matter/ha and, when the variable yields were taken into account, these represented coefficients of variation of 15.6 and 19.0%, respectively. By using the coefficient of variation as the criterion for precision, pre-grazing regressions were significantly more precise than post-grazing regressions. In practice, visual assessment by a double sampling procedure can be used to estimate pre- and post-grazing yields in dairy cow grazing experiments where herbage intakes and growth rates are required, provided sufficient readings are taken to allow an acceptable level of precision. It is suggested that about ten standards are required to formulate a calibration regression regardless of whether or not the pasture to be assessed has been grazed. Although the double sampling technique may be suitable for research purposes, it has been demonstrated that the completely subjective eye appraisal, often used by farmers and their advisers for feed budgeting, can result in many incorrect assessments. A more objective technique needs to be developed for this purpose.

A note on supplements for dairy cows offered silage of high digestibility

1977 ◽  
Vol 25 (3) ◽  
pp. 397-400 ◽  
Author(s):  
M. E. Castle ◽  
W. C. Retter ◽  
J. D. Metcalfe
Keyword(s):  
Organic Matter ◽  
Dairy Cows ◽  
Crude Protein ◽  
Dry Matter ◽  
Matter Content ◽  
Dry Matter Content ◽  
Grass Silage ◽  
Lactating Dairy Cows ◽  
Digestible Organic Matter ◽  
The Mean

SUMMARYGrass silage with a dry-matter content of 20·7%, and containing 18·9% crude protein and 67·0% digestible organic matter in the dry matter was self-fed to 20 lactating dairy cows for 18 weeks. In addition, 9 kg of brewers' grains with a dry-matter content of 28·8% was offered to each cow daily. The two supplement treatments were a barley mix and a groundnut cube containing 11·9 and 33·5% crude protein in the dry matter respectively. The barley was given at the rate of 4 kg/10 kg milk, and the groundnut at 1·5 kg/10 kg milk. The mean daily yields of milk were 18·9 and 19·4 kg/cow on the barley and groundnut treatments respectively and did not differ significantly.

Supplementation of grazing dairy cows with a brewers grains/treated straw mixture

1990 ◽  
Vol 1990 ◽  
pp. 46-46 ◽  
Author(s):  
J.D. Leaver ◽  
R.C. Campling
Keyword(s):  
Dairy Cows ◽  
Crude Protein ◽  
Dry Matter ◽  
Barley Straw ◽  
Severe Drought ◽  
Grass Silage ◽  
Metabolisable Energy ◽  
Grazing Dairy Cows ◽  
Similar Cost ◽  
Friesian Cows

Supplementary feeding of grazing dairy cows is often uneconomic, and whilst supplementation with silage (buffer feeding) can be worthwhile, this often leads to a depletion of winter forage stores. In this study, a mixture of brewers grains and treated straw was used as a supplement. Offered as a 1:1 mixture in the dry matter (DM), it is a purchased substitute for grass silage, having a similar cost, and similar metabolisable energy (ME) and crude protein (CP) contents. The high seasonality adjustments to milk price in mid-late season make supplementation potentially worthwhile.Experiments were carried out from April to September in 1988 and 1989, which had moderate and very low rainfall respectively. Each year 20 British Friesian cows which calved December to March (1988 experiment) and February-April (1989) were allocated at random to either treatment B or C. In B, the cows were offered a 1:1 mixture (DM basis) of brewers grains and NaOH treated chopped barley straw for 60 minutes after morning milking. In C, the cows received no supplement. Both groups were fed 1.0 kg/day of concentrates in the milking parlour. Due to the severe drought in 1989, concentrate feeding was increased to 5.0 kg/day for all cows during the last 4 weeks of the experiment. Also, urea-treated whole crop wheat was fed at a level of 2.5 kg DM/day during the last 7 days.

The effect of compound composition and silage characteristics on silage intake, feeding behaviour, production of milk and live-weight change in lactating dairy cows

1991 ◽  
Vol 52 (1) ◽  
pp. 11-19 ◽  
Author(s):  
D. A. Jackson ◽  
C. L. Johnson ◽  
J. M. Forbes
Keyword(s):  
Dairy Cows ◽  
Weight Change ◽  
Milk Fat ◽  
Feeding Behaviour ◽  
Dry Matter ◽  
Live Weight ◽  
Productive Performance ◽  
Lactating Dairy Cows ◽  
Principal Energy ◽  
Friesian Cows

ABSTRACTAn experiment was carried out to investigate the effects of compound composition and silage characteristics on silage intake, feeding behaviour and productive performance of dairy cows during the first 25 weeks of lactation. Over a period of 3 years, 36 lactating British Friesian cows (12 per year), in their third or later lactations, were divided into two groups. The cows in each group received either compound S, in which the principal energy source was cereal starch, or compound F containing a mixture of high quality digestible fibre. Cows given compound F ate 2·2 kg more silage dry matter per day (P < 0·05). The type of compound had no effect on the frequency of silage feeding and the time spent eating was significantly different only over weeks 10 to 25 of lactation (P < 0·05), with cows on compound F spending on average 20 min longer feeding per day. Cows on compound F produced 1·7 kg more milk per day than cows on compound S. Although there were no significant differences in the concentration of milk constituents, compound F was associated with higher yields of milk constituents. Significant differences were found between the years of experiment in the frequency of feeding (P < 0·05) and also in the concentration of milk protein and milk fat. There were no significant differences in the magnitude of live-weight change between treatments or year of experiment.

Wartime changes in the winter diet of dairy cows in the Eastern Counties of England

1946 ◽  
Vol 36 (3) ◽  
pp. 222-225
Author(s):  
G. H. N. Pettit
Keyword(s):  
Organic Matter ◽  
Sugar Beet ◽  
Dairy Cows ◽  
Dry Matter ◽  
Daily Ration ◽  
Important Place ◽  
Modest Increase ◽  
Winter Diet ◽  
Digestible Organic Matter ◽  
Wheat Products

The general characteristics of a group of thirtynine herds of dairy cows in the Eastern Counties of England, and the method of obtaining information about their diet during the winters 1938–9 to 1942–3 inclusive, are briefly described.The first three winters of the war show a continuous decline in starch equivalent and protein equivalent per cow, followed by a recovery during winter 1942–3.Comparing winter 1942–3 with winter 1938–9: Consumption per cow of concentrates declined by one-third, reductions in proprietary compounds and mixtures and in maize and wheat products being outstanding.The more important increases were in oats, straw and succulent foods, notably mangolds, sugar-beet tops and kale.Hay retained its important place with little overall change; a modest increase in silage was restricted to a few herds.The crude weight of the average daily ration increased from 44 to 61 lb., but its dry matter only from 21·0 to 22·6 lb.The residue: total dry matter less digestible organic matter—increased from 7·2 to 8·4 lb. per cow daily. Reference is made to changes in palatability.

scholarly journals The influence of the method of preservation of forages on the digestion in dairy cows. 1. Composition of the forages and digestibility of dry matter, organic matter and nitrogen.

1975 ◽  
Vol 23 (1) ◽  
pp. 3-9
Author(s):  
S. Tamminga ◽  
C.J. van der Koelen
Keyword(s):  
Organic Matter ◽  
Formic Acid ◽  
Dairy Cows ◽  
Crude Protein ◽  
Dry Matter ◽  
Mixed Diet ◽  
Apparent Digestibility

1. Grass from the same sward was ensiled without additive, with 14.6 g formic acid/100 g crude protein or 10.8 g formic acid and 10.6 g formaldehyde/100 g crude protein. Similar grass was dried and pelleted. Drying or ensiling with the mixture reduced solubility of N in the preserved grass but formic acid increased it, and ensiling without additive increased it even more. Apparent digestibility of N in the rumen of cows tended to decrease with decrease in solubility. Digestibility in vitro of the mixed diet given to the cows, calculated from digestibility of the separate components, agreed well with the values in vivo for diets with silages, but was high for that with dried grass. (Abstract retrieved from CAB Abstracts by CABI’s permission)

CHROMIC OXIDE IN DIGESTIBILITY STUDIES WITH LACTATING DAIRY COWS

1969 ◽  
Vol 49 (3) ◽  
pp. 383-388
Author(s):  
A. L. Hoogendoorn ◽  
C. M. Grieve
Keyword(s):  
Dairy Cows ◽  
Conventional Method ◽  
Crude Protein ◽  
Dry Matter ◽  
Chromic Oxide ◽  
Daily Administration ◽  
Apparent Digestibility ◽  
Lactating Dairy Cows ◽  
Holstein Friesian ◽  
Friesian Cows

Chromic oxide (Cr2O3) in paper pellets was used as an indicator for digestibility studies with four Holstein-Friesian cows fed rations composed of different roughage to concentrate ratios. Cows A and B received one pellet, or 3.46 g of Cr2O3, whereas cows C and D received three pellets, or 10.38 g of Cr2O3, daily.Recovery of Cr2O3 in the feces varied from 84 to 103% for animals A and B and from 92 to 95% for animals C and D. The coefficients of apparent digestion of dry matter were lower (P < 0.01) when the Cr2O3 method was used instead of the conventional method. When samples were taken at 0500, 0900, 1300 and 1700 hours, the Cr2O3 method gave average estimates of digestibility for animal pairs A, B and C, D that were 94.2 and 97.5% of those obtained by the conventional method. Standard deviations for both the Cr2O3 and conventional methods were relatively high.Excretion patterns of Cr2O3 were not signicantly correlated with those of crude protein, phosphorus and calcium. The average concentrations of crude protein, phosphorus and calcium in compounded feces samples collected at 0500, 0900, 1300 and 1700 hours were 101.3, 100.6 and 96.7% of those in samples of the total excretions.The daily administration of 10.38 g of Cr2O3 at 0900 hours for eight days, and the collection of fecal grab samples at 0500, 0900, 1300 and 1700 hours daily during the last five days seemed satisfactory for estimating apparent digestibility of dry matter.

The production and composition of milk from dairy cows fed hay and supplemented with either brewers' grains or rolled barley grain

1982 ◽  
Vol 22 (116) ◽  
pp. 155 ◽  
Author(s):  
SC Valentine ◽  
RB Wickes
Keyword(s):  
Dairy Cows ◽  
Milk Fat ◽  
Dry Matter ◽  
Barley Grain ◽  
Metabolizable Energy ◽  
Energy Requirements ◽  
Price Ratio ◽  
Nutritive Values ◽  
Friesian Cows

Four groups of seven Friesian cows were offered 70% of their calculated metabolizable energy requirements as pasture hay and either 2.4, 4.8 or 7.2 kg/d of dry matter (DM) as wet brewers' grains or 3.9 kg DM/d as rolled barley. A further group of cows received no supplement. The quantities of brewers' grains offered were calculated from in vitro digestible DM content to provide lo%, 20% and 30%, respectively, of metabolizable energy requirements and the rolled barley 30% of metabolizable energy requirements. The cows consumed a mean of 2.2,4.3 and 6.1 kg DM/d, respectively, as brewers' grains and 3.9 kg DM/d as rolled barley. The daily yields of milk (litres), protein (kg) and solids not fat (kg), respectively, were greater (P < 0.05) for the cows offered brewers' grains at 4.8 kg DM/d (1 5.6,0.49, 1.36) and 7.2 kg DM/d (16.4, 0.54, 1.45) than for the cows offered rolled barley (13.3, 0.45, 1.21). Daily yields of milk fat from the cows offered either 4.8 or 7.2 kg DM/d of brewers' grains or rolled barley did not differ significantly. There were no significant differences between treatments in liveweight change. It was concluded that wet brewers' grains and rolled barley offered as supplements to dairy cows fed hay have similar nutritive values for milk production. It was calculated that for milk fat production the break even landed price ratio of brewers' grains to barley is 1:1.26.

EFFECT OF SELENIUM SUPPLEMENTATION ON COPPER METABOLISM IN DAIRY COWS

1986 ◽  
Vol 66 (4) ◽  
pp. 1009-1018 ◽  
Author(s):  
W. T. BUCKLEY ◽  
S. N. HUCKIN ◽  
L. J. FISHER ◽  
G. K. EIGENDORF
Keyword(s):  
Superoxide Dismutase ◽  
Stable Isotope ◽  
Dairy Cows ◽  
Key Words ◽  
Dry Matter ◽  
Copper Metabolism ◽  
Selenium Supplementation ◽  
Holstein Cows

Eight Holstein cows were fed a diet supplemented with selenium at a subtoxic level (2.37 mg kg−1 dry matter), or the same diet without selenium supplementation (0.31 mg kg−1 dry matter), for 276 d of lactation. Copper-65, a stable isotope, was administered intravenously after 14 d of adaptation to the diets, and samples of milk, blood and liver were obtained at intervals throughout the trial. The effect of selenium supplementation on copper metabolism of the cows was evaluated by determining concentrations of copper in plasma, milk and liver, by determining the activities of ferroxidase in plasma and superoxide dismutase in erythrocytes and by determining the pattern of dilution of the copper-65 tracer in plasma, milk and liver. No effect of selenium supplementation on any of the parameters of copper metabolism was observed. It was concluded that an interaction between copper and selenium did not occur under the conditions imposed in this study. Key words: Copper, selenium, interaction, dairy cows, copper stable isotope

The effects of raising post-oestrus progesterone concentrations on luteal activity in post-partum dairy cows

1999 ◽  
Vol 68 (3) ◽  
pp. 527-532 ◽  
Author(s):  
A. O. Darwash ◽  
G. L. Ward ◽  
G. E. Lamming ◽  
J. A. Woolliams
Keyword(s):  
Dairy Cows ◽  
Untreated Control ◽  
Luteal Phase ◽  
Post Partum ◽  
Milk Samples ◽  
Holstein Friesian ◽  
The Mean ◽  
And Control ◽  
Phase Length ◽  
Friesian Cows

AbstractIn order to investigate the rationale of manipulating post-ovulation progesterone (P4) concentrations, luteal activity was measured in 10 Holstein-Friesian cows treated with a progesterone-releasing device (CIDR, 1·9 g P4) inserted on the morning of day 2 post-oestrus for a period of 7 days and compared with 10 untreated control animals. Milk samples were collected daily during afternoon milking from 7 days pre- to 24 days post-oestrus and P4 concentrations were measured using enzyme-linked immuno-sorbent assay (ELISA). The milk P4 profiles were used to assess the effects of early post-oestrus P4 elevation on five intervals of the luteal phase. In the treated (T) and control (C) animals, the mean interval from oestrus to P4 rise (≥3 μg/l), was 2·38 (s.e. 0·18) and 4·90 (s.e. 0·28) days, respectively, (P < 0·01). The mean interval from oestrus to the attainment of peak P4 concentrations was not significantly different (P > 0·05) between the T (14·75 (s.e. 1-62) days) and С (14·30 (s.e. 0·70) days) animals, with cows in the T group showing a more variable (F7 9 = 4-30, P < 0·05) interval to the occurrence of the peak. The interval from peak P4 to corpus luteum (CL) regression (when P4 fell below ≥3 μg/l) was not significantly different between the T (4·13 (s.e. 1·30 days) and С (5·60 (s.e. 0·88) days) groups. Furthermore, CIDR insertion did not alter luteal phase length, number of days with P4 concentrations ≥3 μg/l (T = 16·50 (s.e. 0·80) v.C = 15·00 (s.e. 0·47) days) or the interval from oestrus to CL regression (T = 18·88 (s.e. 0·79) v.C = 19·90 (s.e. 0·41) days). We conclude that treatment with CIDR 2 days after oestrus successfully increased the availability of P4 to cows without significantly affecting luteal phase characteristics.

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