Seasonal Variations in the Blood Plasma Carotene and Vitamin A of Adult Dairy Cattle

Six 9-month-old female Dutch Friesian cattle were given hay and pelleted concentrates with added 130 g CaCO3 or 100 g Na2HPO4 daily for periods of 50 days each. The supplements did not significantly influence growth or vitamin A, Cu or Mn in liver or blood plasma, although more P tended to retard growth. Liver vitamin A, Cu and Mn generally decreased significantly with time. Cu was more closely related to growth than vitamin A or Mn. A fall of Cu in blood plasma and liver was associated with a fall in the vitamin A in liver and with an increase of vitamin A in plasma.-V. J. B. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Seasonal variations in the availability of fodder resources and practices of dairy cattle feeding among the smallholder farmers in Western Usambara Highlands, Tanzania

Tropical Animal Health and Production ◽

10.1007/s11250-018-1609-4 ◽

2018 ◽

Vol 50 (7) ◽

pp. 1653-1664 ◽

Cited By ~ 2

Author(s):

David Maleko ◽

Wai-Tim Ng ◽

George Msalya ◽

Angello Mwilawa ◽

Liliane Pasape ◽

...

Keyword(s):

Dairy Cattle ◽

Seasonal Variations ◽

Smallholder Farmers ◽

Cattle Feeding

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Studies on the properties of New Zealand butterfat: VII. Effect of the stage of maturity of ryegrass fed to cows on the characteristics of butterfat and its carotene and vitamin A contents

Journal of Dairy Research ◽

10.1017/s0022029900011250 ◽

1963 ◽

Vol 30 (1) ◽

pp. 59-66 ◽

Cited By ~ 11

Author(s):

F. H. McDowall ◽

W. A. McGillivray

Keyword(s):

New Zealand ◽

Vitamin A ◽

Seasonal Variations ◽

Monozygotic Twin ◽

Early Summer ◽

Short Rotation ◽

Feeding Trials

SummaryIn two outdoor feeding trials with monozygotic twin cows during the spring and early summer months the effects of mature and immature H1 short rotation ryegrass on the composition of the butterfat produced and on the carotene and vitamin A contents of the butterfat and the blood were compared. In both trials the characteristics investigated were markedly affected by the stage of maturity of the grass. The butterfat from cows receiving immature ryegrass was more unsaturated and had higher carotene and vitamin A contents than that from cows receiving mature ryegrass. The blood of cows fed immature ryegrass also contained more carotene than the blood of cows fed mature ryegrass.It is suggested that variation in the stage of maturity of New Zealand dairy pastures throughout the year is an important factor contributing to the seasonal variations in the characteristics and the carotene and vitamin A contents of commercial butterfat. The influence of stage of maturity is probably associated with the quantity and nature of the pasture lipids.

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