The effect of the plane of energy nutrition of the cow on the secretion in milk of the constituents of the solids-not-fat fraction and on the concentrations of certain blood-plasma constituents

Rook, J. A. F.

doi:10.1079/bjn19610012

Cited by 86 publications

(28 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Changes in concentrations of free amino acids in plasma have been used by Rook & Line (1961) as an index for predicting the adequacy of the diet. They observed that increases in a-amino N levels in plasma were associated with plane of nutrition and milk protein yields.…”

Section: Discussionmentioning

confidence: 99%

Silage and dairy cow production

Rogers

Bryant

McLeay

1979

New Zealand Journal of Agricultural Research

View full text Add to dashboard Cite

Cows were offered constant amounts of unwilted pasture silage or pasture in 5 experiments. The milk yield and milk protein concentration of cows offered silage were increased by abomasal infusions of casein in all experiments. Infusions of 300 gj day casein raised milk and protein by an average of 1.1 kgj day and 0.19% respectively. Methionine (12 gjday) gave a similar response to casein. Isocaloric infusion of glucose did not alter milk yield or milk protein above the controls on the silage ration. Abomasal infusions of casein increased milk yield of cows offered pasture but responses were significantly less than obtained with silage. The studies demonstrate that the amount of protein entering the duodenum of cows fed high moisture pasture silage limited milk production and that methionine was a major amino acid limiting the synthesis of milk and its constituents.

show abstract

Section: Discussionmentioning

confidence: 99%

Silage and dairy cow production

Rogers

Bryant

McLeay

1979

New Zealand Journal of Agricultural Research

View full text Add to dashboard Cite

show abstract

“…The observation that content of milk fat was low during glucose infusion is consistent with enhanced lipogenesis in adipose tissue, at the expense of milk fat production, under the influence of elevated levels of plasma insulin (see Annison and McDowell 1980). The higher levels of solids-not-fat in milk of glucose-infused ewes may be explained by increased synthesis of milk protein as a result of the increase in energy supply (Rook and Line 1961).…”

Section: Glucose Biokineticsmentioning

confidence: 99%

The Importance of Glucose Supply at the Initiation of Artificial Lactation in the Ewe

Leenanuruksa¹,

McDowell²

1982

Aust. Jnl. Of Bio. Sci.

View full text Add to dashboard Cite

Ewes induced to lactate artificially were given continuous intravenous infusions of either saline or glucose in saline during the first 5 days of lactation. Glucose-infused ewes secreted significantly greater (P < 0·05) amounts of milk than control ewes during the first 10 days of lactation. On the tenth day of lactation glucose-infused ewes secreted approximately twice as much milk as control ewes (c. 320 v. 160 g/day). Plasma concentrations of glucose and insulin were significantly higher (P < O· 05) on the first 2 days of lactation for glucose-infused than control ewes.The results suggest that glucose supply to the mammary gland at lactogenesis may be rate-limiting for milk production during early lactation.

show abstract

“…Dale, Vik-Mo andFjellheim 1979;Espinasse and Ruckebush 1976;Parker 1976) while during reserve storing the NEFA concentrations are lower (Holmes and Lambourne 1970). The practical application of NEFA levels in the blood plasma as the indicator of the energy intake adequacy has, however, been questioned on the basis of homeostatic mechanisms (Rook and Line 1961), the variability of their relationships (Fisher et aI. 1975) and also on the basis of short-term daily fluctuations in NEFA which decrease after feeding and increase with fattening and with mild excitement (Holmes and Lambourne 1970).…”

mentioning

confidence: 99%

Influence of Energy-yielding Nutrients in Summer and Winter Feed Rations on the Levels of Non-esterified Fatty Acids in the Blood Plasma of Cows in Various Lactation Phases

Lebeda¹,

Prikrylová²

1981

Acta Vet. Brno

View full text Add to dashboard Cite

Lebeda M., Pfikrylova J.: Influence of Energy-yielding Nutrients in Summer and Winter Feed Rations on the Levels of Non-esterified Fatty Acids in the Blood Plasma of Cows in Various Lactation Phases. Acta vet. Bmo, 50, 1981: 179 -189. The NEFA concentration in the blood plasma of 552 cows held at large-scale production units was determined and the degree of requirement coverage of digestible nitrogen substances (DNS) and of energy (starch equivalent SE) and their ratio according to the Czechoslovak Standard CSN 46 7070 was found. Ten feed rations and 178 cows were included into the period of green food, 21 feed rations and 374 cows in the winter feeding period. The sets of 18 cows were divided into groups containing six animals each and were examined: 1. in the 1st-2nd month of lactation, 2. in the 4th-6th month of lactation and 3. in the 8th-9.5 month of pregnancy, in the dry period.The NEFA concentrations in the whole cow popUlation were found to be significantly (P < 0.01) higher if summer feed rations were used (0.165 mmol .1-1 ± ± 0.138) with a marked average surplus of DNS and SE when compared with winter feed rations (0.131 mmol .1-1 ± 0.153) with a mild average deficiency of DNS and small surplus of SE. The difference of summer and winter NEFA levels in the whole cow population is caused first of all by significantly (P < 0.001) higher NEFA values in cows in the first lactation phase (0.23 mmol . 1-1 ± 0.19 in summer; 0.145 mmol .1-1 ± 0.161 in winter) which have in average a slight DNS deficiency and higher SE deficiency in summer and higher deficit of DNS and SE within the level of the standard in winter. The NEFA concentrations of cows in the first lactation phase and of late-pregnant cows (0.168 mmol .1-1 ± 0.142 in summer; 0.145 mmol.I-1 ± 0.1428 in winter) were found to be both in summer and winter significantly (P < 0.001) higher than of those in the second lactation phase (0.086 mmol .1-1 ± 0.0767 in summer; 0.078 mmol .1-1 ± 0.0635 in winter).The NEFA concentration of cows in the first lactation phase and late-pregnant cows was found to differ significantly neither in summer nor in winter although there is a substantial difference in the coverage of energy nutrient requirement. The reasons of different NEFA concentrations in individual phases of a reproduction cycle from the point of view of found saturation of energy nutrient requirements and of the influence of other factors, the applicability of plasma NEFA determination as an indicator of adequacy of cow nutrition have been discussed.Cows, digestible nitrogen substances, starch equivalent, calorie-protein ratio, plasma NEFA, first and second lactation phases, late pregnancy.Non-esterified fatty acids (NEFA) present in blood plasma are loosely bound to albumin. They are released from this bond during oxidation or during the reserve deposition, the source of NEF A being the hydrolysis of triglycerides from food. This takes partly place in the intestine and to a greater extent in liver. Another source of NEFA is seen in the hydrolys...

show abstract

The effect of the plane of energy nutrition of the cow on the secretion in milk of the constituents of the solids-not-fat fraction and on the concentrations of certain blood-plasma constituents

Cited by 86 publications

References 11 publications

Silage and dairy cow production

Silage and dairy cow production

The Importance of Glucose Supply at the Initiation of Artificial Lactation in the Ewe

Influence of Energy-yielding Nutrients in Summer and Winter Feed Rations on the Levels of Non-esterified Fatty Acids in the Blood Plasma of Cows in Various Lactation Phases

Contact Info

Product

Resources

About