Factors Affecting Differences Between Milk Fat Tests Obtained in the Production Testing Programs and from Semimonthly Composited Samples

Milk producers in the UK are paid according to their production of milk fat, protein and lactose. The production quota system also includes an element restricting fat production. It is therefore important to be able to predict the changes in production of milk solids arising from changes in feed inputs. There are few published predictive models for this purpose (e.g. Sporndly 1989, Emery, 1978) and none under UK conditions. This is a preliminary study to identify and quantify some of the factors affecting yields of milk constituents as a first stage in the development of predictive models.

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Effect of duration and pattern of underfeeding in early lactation on milk production and reproduction of dairy cows

Australian Journal of Experimental Agriculture ◽

10.1071/ea9790395 ◽

1979 ◽

Vol 19 (99) ◽

pp. 395 ◽

Cited By ~ 19

Author(s):

C Grainger ◽

G Wilhelms

Keyword(s):

Milk Fat ◽

Dry Matter ◽

Post Partum ◽

Residual Effects ◽

Early Lactation ◽

Lactation Performance ◽

Factors Affecting ◽

Poor Understanding ◽

Moderate Condition ◽

Ad Libitum

Eighty cows of mixed breeds were fed so that they calved in moderate condition, and were then strip-grazed at different rates over the first ten weeks of lactation. Two levels of feeding were used factorially ; either ad libitum pasture intake (H) or an allowance of pasture which resulted in an intake of 7 kg of pasture dry matter cow-1 day-1 (L), for the first or second five-week period. After ten weeks, all cows were grazed as one group as well as seasonal conditions permitted. The effects of five-week periods of underfeeding on milk, milk fat and protein yield were equal and additive over the first ten weeks of lactation, HL and LH groups producing 11 kg and LL group 22 kg less milk fat than the HH group. Residual effects, however, from week 11 to the end of lactation differed markedly between treatments, the LH group producing the same as, but HL and LL groups producing 9 and 21 kg less than, the HH group. Residual effects of only 0.7 and 1.0 times the immediate effect were recorded for underfeeding in the first five and ten weeks of lactation, respectively. Cows underfed in early lactation gained more liveweight in later lactation at the expense of milk yield. An extra 10 kg pasture dry matter was required in early lactation to give an extra kilogram of milk fat over the lactation. The calving to conception interval in the LL group was 18 days longer than in the HH group (P < 0.05). The delay was associated with both a longer post-partum anoestrus and a higher number of services per conception. There was no effect of stage of underfeeding (HL vs LH) on reproductive performance. The poor understanding of factors affecting residual effects from underfeeding in early lactation is highlighted. As pattern of underfeeding has little effect on lactation performance, this gives the farmer considerable flexibility in allocating feed supplies in early lactation.

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Quantitative animal nutrition and metabolism: a general review

Australian Journal of Agricultural Research ◽

10.1071/ar9930333 ◽

1993 ◽

Vol 44 (3) ◽

pp. 333 ◽

Cited By ~ 1

Author(s):

DG Armstrong

Keyword(s):

Protein Synthesis ◽

Energy Metabolism ◽

Milk Fat ◽

Milk Protein ◽

Intestinal Wall ◽

Host Animal ◽

Rumen Microorganisms ◽

Factors Affecting ◽

Heat Increment ◽

Farm Livestock

Examples of increasing productivity of livestock enterprises over the last three to four decades, and the contribution to such advances, of scientific knowledge including that of the nutrition of farm livestock are referred to. Space limitations neccessitate restricting the review to consideration of ruminant livestock, with particular emphasis on ruminant digestive processes, on milk synthesis and on certain aspects of energy metabolism. Factors affecting the supply of amino acids to the host animal are referred to. The importance of synchronising N and energy supply to the rumen microorganisms to maximize microbial protein synthesis is emphasised and the need for knowledge of the extent to which particular feed proteins escape fermentation within the rumen. Concerning milk synthesis, the importance of an adequate supply of glucose or glucose precursors is mentioned as are the causes of the low milk fat syndrome. Limitations to existing knowledge of amino acid supply and milk protein synthesis are noted. Finally, aspects of ruminant energy metabolism studies are considered; particular stress is given to the importance of energy transactions in the intestinal wall as a major contributor to overall heat increment.

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Factors affecting the fat globule sizes during the homogenization of milk and cream

Journal of Dairy Research ◽

10.1017/s0022029900018100 ◽

1964 ◽

Vol 31 (2) ◽

pp. 195-200 ◽

Cited By ~ 36

Author(s):

J. D. S. Goulden ◽

L. W. Phipps

Keyword(s):

Flow Rate ◽

Milk Fat ◽

Empirical Equation ◽

Applied Pressure ◽

Homogenization Temperature ◽

Fat Content ◽

Factors Affecting ◽

Fat Globule ◽

The Mean

SummaryThe homogenization of milk and cream with a piston-type homogenizer has been studied. An examination has been made of the influences upon the mean fat globule diameters of changes in milk fat content, flow rate and homogenization temperature. The results are discussed in terms of the variations in the parameters q and P0 of the empirical equation d = (P0/P)q relating the globule diameter d to applied pressure P.

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Some factors affecting hydrogenation of milk fat

Journal of the American Oil Chemists Society ◽

10.1007/bf02545209 ◽

1974 ◽

Vol 51 (2) ◽

pp. 26-30 ◽

Cited By ~ 3

Author(s):

Lloyd M. Smith ◽

Andres Vasconcellos

Keyword(s):

Milk Fat ◽

Factors Affecting

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Carotenoids, ergosterol and tocopherols in fresh and preserved herbage and their transfer to bovine milk fat and adipose tissues: A review

Journal of Agrobiology ◽

10.2478/v10146-012-0001-7 ◽

2012 ◽

Vol 29 (1) ◽

pp. 1-13 ◽

Cited By ~ 16

Author(s):

Pavel Kalač

Keyword(s):

Milk Fat ◽

Bovine Milk ◽

Alpha Tocopherol ◽

Maize Silage ◽

Forage Crops ◽

Adipose Tissues ◽

Factors Affecting ◽

Preservation Method ◽

Fat Soluble Vitamins ◽

Β Carotene

Abstract The requirements of cattle for the fat-soluble vitamins A, D and E, their provitamins and some carotenoids have increased under conditions of intensive husbandry with insufficient provision of fresh forage, their cheapest natural source. Moreover, bovine milk fat and adipose tissues participate in the intake of these micronutrients by humans. Four major carotenoids occurring in forage crops are lutein, all-trans-β-carotene, zeaxanthin and epilutein. Fresh forage is their richest source. Losses are significantly higher in hay as compared with silage, particularly if prepared from unwilted herbage. Maize silage is a poor source of carotenoids as compared with ensiled grasses and legumes. Ergosterol contents in forages increase under environmental conditions favourable for the growing of moulds, particularly at higher humidity and lower temperatures. Credible data on changes of ergosterol during herbage preservation, particularly drying and ensiling, have been lacking. Alpha-tocopherol is the most important among eight related compounds marked as vitamin E. It is vulnerable to oxidation and herbage ensiling is thus a safer preservation method than haymaking. As with carotenoids, maize silage is a poor source of α-tocopherol. Overall, information on factors affecting the content of ergosterol and tocopherols in fresh herbage, on changes during forage preservation and on transfer to bovine fats has been much more limited than data for β-carotene.

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Effect of Dietary Vegetable Sources Rich in Unsaturated Fatty Acids on Milk Production, Composition, and Cheese Fatty Acid Profile in Sheep: A Meta-Analysis

Frontiers in Veterinary Science ◽

10.3389/fvets.2021.641364 ◽

2021 ◽

Vol 8 ◽

Author(s):

Einar Vargas-Bello-Pérez ◽

Babak Darabighane ◽

Florencia E. Miccoli ◽

Pilar Gómez-Cortés ◽

Manuel Gonzalez-Ronquillo ◽

...

Keyword(s):

Effect Size ◽

Milk Fat ◽

Unsaturated Fatty Acids ◽

Meta Analysis ◽

Milk Composition ◽

Fat Percentage ◽

Factors Affecting ◽

Nutritional Strategy ◽

Meta Regression ◽

Effect Of Feeding

A meta-analysis was conducted to analyze the effects of different dietary vegetable sources rich in unsaturated FA (UFA) on sheep cheese FA profile. This study also quantified the overall effect of feeding sheep with vegetable sources rich in UFA (linseed, flaxseed, sunflower seed, canola, olive oil, bran oil, and olive cake), on milk yield (MY) and milk composition. A literature search was conducted to identify papers published from 2000 to 2019. Effect size for all parameters was calculated as standardized mean difference. Heterogeneity was determined using I2 statistic, while meta-regression was used to examine factors influencing heterogeneity. Effect size was not significant for MY, milk fat percentage (MFP), and milk protein percentage (MPP). Dietary inclusion of vegetable sources rich in UFA decreased the effect size for C12:0, C14:0, and C16:0 and increased the effect size for C18:0, C18:1 t-11, C18:1 c-9, C18:2 c-9, t-11, C18:2 n-6, and C18:3 n-3. Heterogeneity was significant for MY, MFP, MPP, and overall cheese FA profile. Meta-regression revealed days in milk as a contributing factor to the heterogeneity observed in MFP and MPP. Meta-regression showed that ripening time is one of the factors affecting cheese FA profile heterogeneity while the type of feeding system(preserved roughages vs. pasture) had no effect on heterogeneity. Overall, inclusion of dietary vegetable sources rich in UFA in sheep diets would be an effective nutritional strategy to decrease saturated FA and increase polyunsaturated FA contents in cheeses without detrimental effects on MY, MFF, and MPP.

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Environmental factors affecting milk, fat and protein yields in Jersey cattle in Zimbabwe

Tropical Animal Health and Production ◽

10.1007/s11250-010-9750-8 ◽

2010 ◽

Vol 43 (3) ◽

pp. 665-667 ◽

Cited By ~ 3

Author(s):

Edward Mtunduwatha Missanjo ◽

Venancio E. Imbayarwo-Chikosi ◽

Tinyiko E. Halimani

Keyword(s):

Environmental Factors ◽

Milk Fat ◽

Factors Affecting ◽

Jersey Cattle

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Factors affecting goat milk fat yield

Žemės ūkio mokslai ◽

10.6001/zemesukiomokslai.v24i3.3555 ◽

2017 ◽

Vol 24 (3) ◽

Cited By ~ 2

Author(s):

Evaldas Šlyžius ◽

Birutė Šlyžienė ◽

Vaida Lindžiūtė

Keyword(s):

Milk Fat ◽

Goat Milk ◽

Fat Content ◽

Dairy Goat ◽

Dairy Goats ◽

Factors Affecting ◽

Stage Of Lactation ◽

Goat Population ◽

Main Factors ◽

Fat Yield

The objective of the paper was to investigate the main factors determining the yield of fat in goat milk in the dairy goat population of Lithuania. The research was carried out on a total of 1,079 dairy goats (4 breeds: Czech White Shorthaired (n = 610), Saanen (n = 364), Lithuanian native (n = 94) and Anglo-Nubian (11)) in 7 dairy farms. The average milk yield during lactation was 797.42 (±53.3) kg. The average milk fat content was 4.14% (±0.4). The research of the goat milk fat content demonstrated that the indicators investigated in different herds varied. The highest milk fat content in percent was determined among AngloNubian – 5.2%. The milk fat content of all breeds of goats increased with increasing the parity up to the 4–6th parity, respectively, and started decreasing then, after reaching the peak. While assessing the quantity of milk fat during the stage of lactation, the highest milk fat content was determined during the first months (4.5–4.7%) and at the end of lactation (4.5%). The research performed by us showed that such factors as breed, parity, stage of lactation and herd had an impact on the quantity of goat milk fat.

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