bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of concentrates of high or low starch equivalent, both fed at two levels, on the milk production of dairy cows
Authors: Castle M. E. , Maclusky D. S. , Morrison J. , Watson J. N. 
Published: June 2009

1. In a winter feeding trial, using eight Ayrshire cows, two concentrates with digestible crude protein contents of 15% and starch equivalents of 63 and 79 were each fed at 2·6 and 4·6 lb./gal. of milk.2. The basal ration was hay, silage, dried grass and fodder-beet.3. Milk yield was significantly increased from 30·9 to 34·7 lb./day when the amount of concentrate fed increased from 2·6 to 4·6 lb./gal., but the average milk yields when the concentrates low in starch equivalent were fed did not differ significantly from those obtained when the concentrates high in starch equivalent were fed at the same levels.4. The fat content of the milk was similar on all four rations with an average value of 3·84%, whereas the solids-not-fat varied from 8·53% on the low starch concentrate fed at the lower rate to 8·77% on the high starch concentrate fed at the higher rate.5. The cows which were fed at the rate of 4·6 lb./gal. were significantly heavier by an average of 33 lb./cow than the ones fed at the rate of 2·6 lb./gal. The two different qualities of concentrate did not cause differences in live weight.6. The weight of dry matter in the basal ration consumed per day was similar on all four treatments.7. A comparison of feeding costs and the value of the milk showed that the largest margin was obtained with the low starch equivalent concentrate fed at the rate of 2·6 lb./gal.8. It was concluded that because of the loss in live weight on the lowest level of feeding, and because the quality of the concentrate gave no improvement in milk yield or liveweight and little improvement in milk composition, the optimal level of feeding in this experiment was 4·6 lb./gal. of the low starch equivalent concentrate.
Parition of riboflavin in cow's milk
Authors: Modi V. V. , Owen E. C. , Darroch R. A. 
Published: June 2009

1. The partition of riboflavin between the free and the protein-bound forms was measured in the milk of six Ayrshire cows, three of which were treated with l-thyroxine.2. As lactation progressed there was a slow decline in the total riboflavin content of the milk for which the initial values were 0·86 to 1·09 µg./ml. milk. The rate of decline ranged from 0·01 to 0·003 µg./ml. milk per day.3. Thyroxine had its expected effects in stimulating milk yield and heart rate, and in preventing the rise of phosphatase in the milk as lactation progressed, but it did not affect either the concentration or the partition of riboflavin.4. Reasons are advanced for the marked contrast between the effect of thyroxine in increasing the phosphorylation of thiamine and the absence of any such effect on riboflavin.We thank Miss S. McLauchlan and Miss M. Lightbody for technical assistance, and Glaxo Laboratories Ltd., Greenford, Middlesex, for a gift of L-thyroxine.
The growth of aerobic spore-forming bacilli in sterilized milk
Authors: Higginbottom Constance , Taylor Margaret M. 
Published: June 2009

SummaryThe sterilization of homogenized milk at 115·5°C for 15 min in bottles having a partial vacuum in the headspace produced conditions inhibitory to the growth from very small numbers of spores ofBacillus subtilis, B. licheniformis, B. cereusandB. breviswhen compared with growth in the same milk sterilized in open bottles.B. circulansdiffered from the other strains tested in showing greater inhibition in milk sterilized in open bottles than in milk sterilized under partial vacuum.The extent of the inhibition became less as the size of the inoculum was increased. It became less also as the temperature of incubation approached the optimum growth temperature of the bacillus, and was influenced by the strain of the bacillus and the source of the milk but not by the degree of heat treatment within the range 107–117·5°C for 15 min. Inhibition was manifested by a prolongation of the lag phase, and in addition with some strains inhibition of spore germination could be demonstrated.Spore formation following vegetative growth occurred more readily in milk sterilized in open than in evacuated bottles.Milks sterilized under partial vacuum frequently failed to show any growth from small inocula in 30 days at 22°C although growth occurred readily in milk sterilized in open bottles.
Certain non-biological properties of sterilized milk in relation to the treatment of the milk and the temperature of heating
Authors: Higginbottom Constance , Taylor Margaret M. 
Published: June 2009

SummaryThe effect of the temperature of laboratory sterilization of homogenized milk on the titratable acidity, the colour of the milk, the yellowing of the filtrate from the Aschaffenburg turbidity test, the acid-ferricyanide-reducing substances and on pH has been determined. The greater changes in these properties in milk sterilized under reduced oxygen tension compared with milk sterilized in open bottles was shown to be due, in part at least, to the slower rate of cooling in the evacuated bottles. Samples of commercial sterilized milk have also been examined and their properties have been compared with those of the sterilized milk produced in the laboratory.
The distribution of bacteria in New Zealand Cheddar cheese
Authors: Rammell C. G. 
Published: June 2009

SummaryThe distribution and development of bacteria during the maturing of New Zealand Cheddar cheese have been studied using stained sections of cheese. The starter streptococci usually occur singly and in small groups throughout the mass of the cheese, their distribution on a microscopic scale being very irregular. In contrast, the bacteria developing later form discrete microcolonies, most of which are associated with the curd junctions. Instead of adding lactobacilli to milk, smaller numbers may be added to the dry curd before cheddaring or after milling. Some observations on the physical structure of cheese are made.
The short-term effects of the level of concentrates given to Ayrshire cows and of adding 0·75 1b sodium acetate to the daily diet
Authors: Balch C. C. , Taylor J. , Thomson I. 
Published: June 2009

Summary1. In an experiment with twenty-four Ayrshire cows, four treatments were compared in a change-over experiment in which each cow completed four periods each of 4 weeks. In all the treatments the cows received daily 4 lb of concentrates and roughage according to their initial live weight. For milk yields above 10 lb the cows received 4 lb of a concentrate mixture per 10 lb of additional milk produced in the previous week in one treatment, and 3 lb in the other three treatments. Two of the treatments with the lower rate of feeding were supplemented with 0·75 lb of sodium acetate daily, given in either one or three doses.2. Digestion trials were made with the hay and concentrates to aid in the estimation of their starch equivalents. The allowance made for the maintenance requirements of the cows appears to have been close to that recommended by Woodman (1957).3. On one treatment the cows in fact received 4·29 lb of concentrates/10 lb of milk produced, and gave on average 36·6 lb of milk (35·2 lb of 4% fat-corrected milk) in the last 2 weeks of the experimental period with a daily decline in milk yield of 0·14 lb/day. On the other treatments the cows in fact received 3·48 lb of concentrates/10 lb of milk produced, and averaged 34·4 lb of milk daily with an average daily decline of 0·21 lb/day; this differed significantly from the rate of decline observed with the higher rate of feeding.4. The addition of 0·75 lb of sodium acetate to the daily diet, in one or three doses, exerted no detectable effect on milk yield or composition, apart from a small effect on the solids-not-fat (S.N.F.) percentage which was of doubtful meaning.5. At the higher rate of concentrate feeding the S.N.F. content was 0·10% higher than at the lower rate of feeding. This difference and the resulting difference in the yield of S.N.F. (0·21 lb daily) were significant.
Hesion and consistency of butter
Authors: Jansen K. 
Published: June 2009

SummaryAn apparatus, which has certain advantages over that designed by Claassens, is described for measuring the combined forces of cohesion and adhesion (‘hesion’). The effects of varying the loading rate are discussed. Heidebroek & Pietsch's theory, which is applicable to adhesion between lubricated metal surfaces, is shown not to hold for butter.Hesions measured with the new apparatus are compared with the frictional and consistency parameters of Prentice's butter extruder and also with the liquid-fat index. The relationships depended largely on temperature. The majority were significant (P < 0·01). A linear relation was found between Prentice's two parameters, leading to a high correlation coefficient (0·88).Preliminary experiments are described on the effects of prolonged working and also on the relationship between hesion and weight variations during the printing of butter.
The composition of Iraqi sheep's milk
Authors: Nejim H. T. 
Published: June 2009

SummaryThe bulked milk from a flock of Awassi sheep was analysed in two successive seasons. In the second season a wider range of analyses of samples taken from the time the first few ewes came into milk until almost the end of the production season (minimum and maximum numbers in milk 8 and 199) gave the following average values: specific gravity, 1·0366; titratable acidity, 0·217%; pH, 6·65; fat, 6·88%; protein, 6·18%; lactose, 5·75%; solids-not-fat, 12·99%; ash, 0·928%; CaO, 0·29%; p2O5, 0·32%; CaO in ash, 31·5%; P2O5 in ash, 34·3%.The results are compared with the published compositional figures for sheep's and cow's milks.
Some aspects of machine milking rate
Authors: Wilson G. F. 
Published: June 2009

SummaryA study was made of the machine milking rates of a sample of Jersey cows comprising daughter-dam pair groups, obtained from thirteen New Zealand herds during mid-lactation.Twenty-one per cent of the variation in maximum rate of flow occurred within herds and the remainder between herds. Differences in the type of preparation of cows for milking did not have a significant effect on the average milking rates for herds. The variance in milking time between cows within poorly prepared herds was greater, however, than that in the better prepared herds.Heritability estimates for maximum rate of flow, derived from the regression of daughters' records on dams' records, were found to be of the order of 80%.
A note on the effect of heat on the colour of goat's milk
Authors: Burton H. 
Published: June 2009

SummaryGoat's milk heated at temperatures in the range 94—120 °C underwent the same colour changes as previously found for cow's milk, i.e. whitening followed by browning. The rate of browning varied with temperature according to Arrhenius's Law, and had a Q10 between 95 and 120 °C of 2·6—2·7. This is slightly lower than the value found for cow's milk. It was difficult to produce whitening curves for milk heated at 75—100 °C because of unexplained reflectance variations. It appeared that the amount of whitening which could be produced became less as the interval after milking increased.
Fatty acid composition of sow's colostrum, milk and body fat as determined by gas-liquid chromatography
Authors: deMan J. M. , Bowland J. P. 
Published: June 2009

SummaryAs determined by gas-liquid chromatography, the mean fatty acid composition (weight percentages of total fatty acids) of milk fat from sows fed a diet to meet U.S. N.R.C. nutrient requirements was: oleic, 35·3; palmitic, 30·3; linoleic, 13·0; palmitoleic, 9·9; stearic, 4·0; myristic, 3·3; linolenic, 2·5; unidentified 0·7 and 0·5, presumably n-odd chain and branched fatty acids; lauric, 0·3; and capric, 0·2. The corresponding fatty acid composition of colostrum fat was: oleic, 41·7; palmitic, 22·5; linoleic, 20·9; palmitoleic, 5·0; stearic, 5·7; myristic, 1·4; linolenic, 2·4; and unidentified acids, 0·3 and 0·1. Dietary fat increased fat levels in the milk and influenced fatty acid composition of the milk fat. Backfat resembled colostrum fat more than milk fat.
Examination of an antibiotic produced by coagulase-negative staphylococci isolated from the bovine udder
Authors: Jones G. W. , Edwards S. J. 
Published: June 2009

SummaryAn antibiotic produced by coagulase-negative staphylococci isolated from the bovine udder was examined by deferred antagonism tests and its inhibitory properties compared with those of other staphylococci. While inhibiting the growth of representative phage types of bovine pathogenic staphylococci, its activity against corynebacteria was more restricted than that of Staphylococcus aureus NCTC 6507 and 8004. Only minimal amounts of inhibitory substance were produced in liquid media, larger amounts were produced on solid media and the incorporation of a blood plasma factor further increased production. The inhibitory substance resisted treatment with pepsin and trypsin and withstood boiling for 30 min. Its characters in relation to inhibitory substances produced by other staphylococci are discussed.
Changes in the quantity and composition of mammary gland secretion in the dry period between lactations. II. The complete dry period
Authors: Smith A. , Wheelock J. V. , Dodd F. H. 
Published: June 2009

SummaryThe changes in yield and composition of mammary gland secretion throughout the whole of the dry period have been investigated in 6 cows. The yields of lactose, potassium, fat and casein decreased to very low values for the greater part of the dry period but then increased slightly just before parturition. Similar trends were observed for sodium and chloride but they were much less marked. During the middle of the dry period the concentrations of sodium, potassium and chloride tended towards those of blood serum while the concentrations of fat and lactose decreased to < 1%.
The C-terminal sequence of amino acid residues of κ-casein isolated from buffalo's milk
Authors: El-Salam M. H. Abd , Manson W. 
Published: June 2009

SummaryWhen κ-casein from buffalo's milk was treated with carboxypeptidase A (EC 3. 4. 2. 1),4 amino acids, valine, threonine, serine and alanine were released from the protein in a manner consistent with the view that they originate in the C-terminal sequence of a single peptide chain. The amounts produced suggest a minimum molecular weight for buffalo κ-casein of approximately 17000, in agreement with the value calculated from the phosphorous content on the basis of the presence of 2 phosphorus atoms/molecule. A comparison is made with the C-terminal sequence reported for bovine κ-casein.
Identification of fatty acids from butterfat using a combined gas chromatograph-mass spectrometer
Authors: Ryhage Ragnar 
Published: June 2009

SummaryThe identification and approximate quantitative determination of methyl esters of fatty acids from commercial butterfat was obtained with a combined gaschromatograph-mass spectrometer instrument. Fifty-two components, straight chain saturated and unsaturated, as well as branched chain compounds, were identified. Seven monomethyl saturated fatty acid methyl ester isomers were identified for both C15and C17, i.e. with chain lengths of 14 and 16 carbon atoms, respectively. Multibranched fatty acids with molecular weights of 326 and 368 were found. The results were obtained in one day.
The major fatty acids in whole milk fat and in a fraction obtained by crystallization from acetone
Authors: Mattsson Sonja , Swartling P. , Nilsson R. 
Published: June 2009

SummarySummer and winter milk-fat samples from 14 dairies in Sweden were fractionated by crystallization from acetone solution (1:8) at 15 °C. The composition of the major fatty acids of the parent milk fat and of the acetone insoluble fraction were examined by GLC, and the gross triglyceride pattern by TLC on plates of silicic acid treated with silver nitrate.The fatty acid composition of the milk fat was similar to that of milk fat from other countries and varied according to season and also, to a smaller extent, from region to region. Four fractions, representing 33–45, 41–34, 18–14 and 7–6 % of the fat and which contained progressively smaller proportions of saturated acids, were obtained by TLC.The acetone insoluble glyceride (AIG) fraction was characterized by a smaller content of short-chain fatty acids and unsaturated fatty acids, and a larger content of saturated long-chain fatty acids, than the parent milk fat. AIGs from summer milk fat contained a larger proportion of C18acids and a smaller proportion of C6–C16acids than AIGs from winter milk fat.Four fractions representing 62–70, 15–8, 16–15 and 7 % of the AIG fraction were obtained by TLC. The distribution of the triglycerides in the AIG fraction differed from that in the parent milk fat, mostly in the relative amounts of glycerides in the 2 most saturated TLC fractions. The seasonal variation was largely confined to these 2 fractions.
Storage of chilled cream in relation to butter quality
Authors: McDowell A. K. R. 
Published: June 2009

SummaryThe quality of fresh and stored butter made from chilled cream collected over 3 days and stored either by accumulation in a vat or by separate storage of each batch was compared with that of butter made from unchilled cream collected over one day.Provided each batch of cream after separation at 85 °F was cooled to 55 °F before addition to the vat, accumulation of cream at either 40 or 48 °F gave butter similar in quality to the control butter. Butter from cream cooled to 55 °F and held at this temperature, however, was slightly inferior in quality. The addition of the cream to the vat with no cooling, or cooling only to 70 °F, after separation gave butter of inferior quality due to rancid or stale flavours.Butter from cream cooled either to 70 or 50 °F before storage of each batch in separate containers at either 40 or 50 °F was only slightly inferior in quality and in keeping quality to the control butter.Defects in the chilled cream butters appeared to be due to lipolysis caused either by activation of the natural lipase of the cream or by lipolytic bacteria or both.
The relationships between dietary fatty acids, plasma lipid composition and milk fat secretion in the cow
Authors: Moore J. H. , Steele W. , Noble R. C. 
Published: June 2009

SummaryThe effects of the isocaloric replacement of starch in a low-fat concentrate mixture by either 5 or 10% ‘stearic acid’ (85% pure) or by 10% ‘palmitic acid’ (85% pure) on the composition of the plasma lipids were investigated in a feeding experiment with 12 cows in mid-lactation. The concentrate mixtures were given with a high roughage diet that supplied daily 4·4 kg of hay and 2·7 kg of sugar-beet pulp. A study was made of the relationships between the compositions of the plasma and milk lipids.The inclusion of 10% ‘stearic acid’ or 10% ‘palmitic acid’ in the concentrate mixture increased the concentration of total plasma fatty acids. Irrespective of dietary treatment, about 40% of the total plasma fatty acids occurred in the cholesteryl ester fraction, 54% in the phospholipid fraction, 3% in the triglyceride fraction and 3% in the unesterified fatty acid fraction. There was a positive curvilinear relationship between the concentration of unesterified fatty acids in the plasma and the yield of total milk fatty acids.In the plasma triglycerides, the concentrations of 16:0 and 16:1 were decreased and the concentration of 18:0 was increased when the concentrate mixture contained ‘stearic acid’; the concentration of 16:0 was increased and the concentrations of 18:0, 18:1 and 18:2 were decreased when the concentrate mixture contained ‘palmitic acid’. Similar changes were observed in the compositions of the plasma unesterified fatty acids when the cows were given the different diets.In the plasma cholesteryl esters, the concentration of 16:0 was decreased and the concentrations of 18:3 and 20:4 were increased when the concentrate mixture contained stearic acid; the concentrations of 16:1, 18:3 and 20:4 were increased and the concentration of 18:2 was decreased when the diet was supplemented with palmitic acid. The addition of stearic acid to the diet increased the concentration of 18:0, 18:1 and 18:3 in the plasma phospholipids but decreased the concentrations of 16:0, 18:2, 20:3 and 20:4. When the diet contained palmitic acid the concentrations of 16:0, 16:1, 18:1 and 18:3 in the plasma phospholipids were increased but the concentrations of 18:0, 18:2 and 20:3 were decreased.The major fatty acid circulating in the plasma of the cows was 18:2, which accounted for about 45% of the total plasma fatty acids. Only about 0·7% of the total plasma 18:2 occurred in the plasma triglycerides.The results are discussed in relation to the changes in the composition of the milk fatty acids produced by the cows when they were given the experimental diets.
Observed ratios of 90Sr/Ca and 137Cs/K in the food of nursing mothers and in their milk
Authors: Calapaj G. G. , Ongaro D. 
Published: June 2009

SummaryThe 90Sr/Ca and 137Cs/K ‘observed ratios’ (OR) in the food intake of nursing mothers and in their milk have been determined. Between 4 and 7 days after parturition, groups of mothers were put on a controlled diet for 4 days. Pooled samples of milk were then taken from each group. 90Sr, Ca, 137Cs and K were determined in the pooled samples and in all foods taken during the experimental period. 90Sr/Ca ratios were determined in 4 experiments and 137Cs/K ratios in 3. The OR for the 4th day's intake did not differ significantly from average ratios for the whole 4 days, so that a state of metabolic equilibrium appears to have been reached. The 90Sr/Ca OR was fairly constant and considerably less than unity, but the 137Cs/K OR was greater than unity and varied considerably between experiments.Since potassium, which is metabolically analogous to caesium, showed a fairly constant ratio between intake and excretion in the milk, the physiological behaviour of 137Cs must be quite different from that of 90Sr. The maternal organism therefore provides the baby with efficient protection against 90Sr but not against 137Cs.
Carbohydrate analysis of the glycopeptides released by the action of rennin on whole milk
Authors: Sinkinson G. , Wheelock J. V. 
Published: June 2009

SummaryA gas-liquid chromatographic method is described for the simultaneous estimation of the carbohydrates attached to the glycopeptides released by the action of rennin on whole milk. The method can also be used for κ-casein. Certain of the findings may be applicable to other glycoproteins or glycopeptides. In particular: (a) the conditions for methanolysis of the carbohydrates from the glycopeptides must be chosen carefully to avoid decomposition ofN-acetyl neuraminic acid; (b) it is not possible to obtain a satisfactory calibration forN-acetyl neuraminic acid using the free acid as a standard.
The detection of clinical mastitis with in-line filters
Authors: Hoyle J. B. , Dodd F. H. 
Published: June 2009

SummaryA simple in-line filter is described which can be fitted into the milk tube of a. milking machine in order to detect clinical mastitis. It consists of a stainless steel mesh, on which the clots are retained, and it is fitted obliquely into a short length of clear plastics tube. The filter has been developed as an alternative to the fore-milk cup. Tests made over 9 months in a 60-cow herd show good agreement between the fore-milk cup and the in-line filter recordings. For general service production the filters are made by moulding.