Effect of decreased milking frequency of cows in late lactation on milk somatic cell count, polymorphonuclear leucocyte numbers, composition and proteolytic activity

1998 ◽  
Vol 65 (3) ◽  
pp. 365-373 ◽  
Author(s):  
ALAN L. KELLY ◽  
SUSAN REID ◽  
PATRICK JOYCE ◽  
WILLIAM J. MEANEY ◽  
JOHN FOLEY

The effects of reducing the frequency of milking of cows in late lactation on milk somatic cell count (SCC), polymorphonuclear leucocyte (PMN) content, chemical composition and proteolytic activity were investigated. Intermittent milking is frequently practised by Irish farmers in late lactation, and the objective of this study was to determine whether this procedure could be linked to altered quality of milk. Seventeen Holstein Friesian cows in late lactation (>215 d in milk) were assigned to two treatment groups, and were either milked twice a day until drying-off (control group) or milked intermittently as the yield fell (test group). Milk composition and enzymic characteristics were measured on two occasions. At the first sampling, day 7, test cows were on once daily milking and at the second, day 15, the test cows were being milked every second day. Milk yields were significantly lower in test than control animals and decreased between days 7 and 15 in both groups. Milk SCC and PMN levels were increased on reducing milking frequency and, at day 15, the increase was not linked to decreased milk yield. Milk lactose levels were significantly decreased and pH, α-lactalbumin levels, plasmin activity and plasminogen activity significantly increased by reducing milking frequency. In conclusion, reduced frequency of milking in late lactation leads to the production of milk that is abnormal in character and this may be linked to reduced quality of dairy products manufactured from such milk.

2005 ◽  
Vol 72 (1) ◽  
pp. 86-92 ◽  
Author(s):  
Marzia Albenzio ◽  
Mariangela Caroprese ◽  
Antonella Santillo ◽  
Rosaria Marino ◽  
Antonio Muscio ◽  
...  

A total of 120 milk samples were collected from Comisana ewes throughout lactation. The ewes were ranked into two somatic cell count (SCC) categories: normal milk (N Milk) with SCC lower than 5·00×105/ml and high somatic cell milk (HSC Milk) with SCC higher than 1·00×106/ml. Milk samples were analysed in triplicate for pH, fat and protein contents, renneting parameters, and plasmin and plasminogen activities. The peptide profile due to total proteolytic activity (endogenous and exogenous enzymes) on α- and β-CNs were determined using urea-PAGE on sodium caseinate (pH 8·0 and pH 5·0) incubated at 37 °C for 4 d after sampling. The peptide profile due to non-plasmin enzyme activities at pH 5·0 was also determined using urea-PAGE. Plasmin activity was higher in the HSC milk than in the N milk throughout the study period. A decrease in plasmin activity was observed in the N milk during mid-lactation, which was probably related to decrease in pH, and in the HSC milk during late lactation, which may be ascribed to an enhanced influx of plasmin inhibitors from the blood stream. Proteolytic patterns in Comisana ewe milk were mainly affected by plasmin activity that increased with the SCC in milk. Also non-plasmin proteolytic activity was strongly enhanced by elevated SCC and resulted in a higher degradation of α-casein than of β-casein. In general, plasmin activity did not increase with the advancement of lactation and exhibited a different trend in HSC and N milk, suggesting that physiological factors did not play a key role in regulating the plasminogen-plasmin system in ewes' milk. Plasmin activity, detected with the colorimetric assay was consistent with proteolytic activity on sodium caseinate shown in urea-PAGE electrophoregram.


2017 ◽  
Vol 3 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Mukta Talukder ◽  
HM Manir Ahmed

Somatic cells are the most essential factors naturally present in milk, and somatic cell count (SCC) is used as an indicator of monitoring mastitis incidence in the herd and also to assess the quality of milk. In addition, SCC is frequently used to determine quality payments to dairy producers. The SCC is directly related to get maximum milk production from individual cow and a lower SCC indicates better animal health, as somatic cells originate only from inside the animal's udder. SCC monitoring is important because as the number of somatic cells increases, milk yield is likely to fall, primarily due to the damage to milk-producing tissue in the udder caused by mastitis pathogens and the toxins they produce, particularly when epithelial cells are lost. Keeping low SSC will allow good quality more raw milk and provide a better product to milk processors whether used as fluid milk or converted to milk based products. Somatic cells containing lipolytic and proteolytic enzymes lead to degrade major nutrients fats and proteins, respectively. Elevated SCC is related to udder inflammation, which leads to alter the normal microbial count and physicochemical parameters of milk, as well as the quality of heat treated fluid milk and milk based product. The objective of this review is to discuss on the SSC and endogenous enzymes released from somatic cells in raw milk as well as effect of somatic cells count and their endogenous enzymes in processed milk and milk based products.Asian J. Med. Biol. Res. March 2017, 3(1): 1-9


2016 ◽  
Vol 12 (1) ◽  
pp. 9-15
Author(s):  
Sylwia Bielińska-Nowak ◽  
Grażyna Czyżak-Runowska

The aim of the study was to determine the influence of the stage of lactation on the yield and quality of sheep milk. The material for the investigation was milk from morning milking of 30 East Friesian sheep in their third to fifth lactation. Milking began after the lambs were weaned and continued for about 120 days. Milk samples were collected individually from the sheep in three stages of lactation: at its peak, during the stabilized stage and at the end (late) lactation. Daily milk yield, total bacterial count, somatic cell count and the basic composition of the milk were determined. The microbiological quality of the milk was very high and the somatic cell count was favourable. As lactation progressed the somatic cell count increased while microbiological quality remained stable. At the end of lactation a significant increase was noted in the concentration of dry matter, protein and fat, accompanied by a decrease in lactose concentration, in comparison with the peak of lactation. Yield was shown to be negatively correlated with fat (–0.63; p≤0.01) and dry matter (–0.53; p≤0.01) and positively correlated with lactose (0.61; p≤0.01).


Author(s):  
Erdal Yayalak ◽  
Musa Yavuz ◽  
Serkan Özkaya

The present study was conducted to investigate the effects of calving season (winter and spring) and parity (first and second parity) on colostrum quality. Colostrum of 42 Holstein cows raised at a private dairy farm was used in this experiment. Calving season and parity had no effects on major components of colostrum. However, somatic cell count (SCC) and the brightness of the colostrum (L*) values were affected by calving season (Pis less than 0.05). The mean of winter colostrum SCC was lower than the spring season (P is less than0.05). The brightness of the colostrum was found to be higher in winter season than in spring season (Pis less than 0.01). Colostrometer has been used to evaluate colostrum quality and Brix refractometer and colorimeter can also be used to assess colostrum quality.


2021 ◽  
Vol 44 (2) ◽  
pp. 213-221
Author(s):  
S. Abdelghany ◽  
N. H. Fahim ◽  
F. Samir ◽  
M. A. Radwan

The study aimed to investigate the association between teat-end hyperkeratosis (THK) and somatic cell count (SCC) and to assess the effect of SCC on milk yield, fat, and protein percentages of Holstein cows. A total of 740 udder quarters of 185 Holstein cows kept in three commercial herds in Egypt were enrolled in the study from May to September 2019. Foremilk samples were collected from udder quarters for assessing milk SCC, fat, and protein percentages. On the same cows, a digital picture of each teat end orifice was taken with a digital camera. Cows’ teats were assessed for THK and classified into two different groups of hyperkeratosis; mild and severe THK. SCC was converted to five classes of somatic cell score (SCS). Simple linear regression was performed to determine the loss of milk yield, fat, and protein percentages. SCC was significantly affected by THK (p<0.0001). About 57% of teats were classified as mild THK and 43% as severe THK. The teats with severe THK recorded higher SCC in milk. It was observed that SCS had a significant effect on fat and protein percentages (p<0.0001). A similar trend was shown for the effect of SCS on milk yield (p<0.05), where the highest values of milk traits were obtained for the lowest SCS. The loss of milk was 220 g/day. Also, fat and protein percentages decreased by 0.11% and 0.08%, respectively, for each unit increase in SCS, from zero to four. In conclusion, severe THK can lead to high SCC, which negatively affects milk traits.


2014 ◽  
Vol 81 (3) ◽  
pp. 275-279 ◽  
Author(s):  
Alexandr Torres ◽  
Lorenzo-Enrique Hernández-Castellano ◽  
Antonio Morales-delaNuez ◽  
Davinia Sánchez-Macías ◽  
Isabel Moreno-Indias ◽  
...  

Goats in Canary Islands are milked once a day by tradition, but in most countries with high technology on farms, goats are milked twice a day, which is known to improve milk yield. Therefore it is important to know whether the increase of milking frequency can improve the production without impairing milk quality. The objective of this study was to investigate the short term effects of three milking frequencies on milk yield, milk composition, somatic cell count (SCC) and milk protein profile in dairy goats traditionally milked once a day. Twelve Majorera goats in early lactation (48±4 d in milk) were used. During a 5-week period, goats were milked once a day (X1) in weeks 1 and 5, twice a day (X2) in weeks 2 and 4, and three times a day (X3) in week 3. Milk recording and sampling were done on the last day of each experimental week. Milk yield increased by 26% from X1 to X2. No differences were obtained when goats were switched from X2 to X3, and from X3 to X2. The goats recovered the production level when they returned to X1. Different patterns of changes in the milk constituents due to the milking frequency effect were observed. Fat percentage increased when switched from X1 to X2, then decreased from X2 to X3, and from X3 to X2, whereas it did not show significant differences from X2 to X1. Milking frequency did not affect the protein and lactose percentages. SCC values were unaffected when goats were milked X1, X2 and X3, but then they increased slightly when milking frequency was returned to X2 and X1. Finally, quantitative analysis showed an increase in intensities of milk protein bands from X1 to X2, but the intensities of casein bands (αS1-CN, αS2-CN, β-CN, κ-CN) and major whey proteins (α-La, β-Lg) decreased from X2 to X3.


2011 ◽  
Vol 78 (4) ◽  
pp. 442-447 ◽  
Author(s):  
Marzia Albenzio ◽  
Antonella Santillo ◽  
Mariangela Caroprese ◽  
Laura Schena ◽  
Donatella Esterina Russo ◽  
...  

This study was undertaken to assess the effect of somatic cell count in ewe milk on i) composition and hygienic traits; ii) plasmin, cathepsin and elastase activities; iii) leukocyte differential count; iv) renneting parameters. Individual ewe milk samples were grouped according to somatic cell count (SCC) into five classes: SC300 (<300 000 cells/ml), SC500 (from 301 000 to 500 000 cells/ml), SC1000 (from 501 000 to 1 000 000 cells/ml), SC2000 (from 1 001 000 to 2 000 000 cells/ml) and SC>2000 (>2 001 000 cells/ml). Individual milk samples were analysed for pH, chemical composition, microbial features, indigenous proteolytic enzymes, differential leukocyte population, and renneting parameters. Milk yield, lactose, protein, non casein nitrogen, microbial features were affected by SCC level. Plasmin and elastase activities were the highest in samples with more than 1 000 000 cells/ml; plasmin had intermediate values in samples with 300 000 to 1 000 000 cells/ml and the lowest in samples with less than 300 000 cells/ml of milk. Cathepsin D showed significantly lower values in SC300 and SC1000 classes than in SC500, SC2000 and SC>2000 classes. The highest percentages of lymphocyte were found in samples with less than 1 000 000 cells/ml, while the highest levels of polymorphonuclear leukocyte were found in samples with more than 1 000 000 cells/ml of milk. Longer clotting time was found in SC>2000 samples, while reduced clot firmness was observed in SC500 and SC>2000 samples. Results on milk yield and on compositional parameters evidenced an impairment of udder efficiency in ewe milk samples starting from 300 000 cells/ml. Plasmin activity in milk can be considered as a marker of the synthetic and secreting ability of the mammary gland; furthermore plasmin and elastase were consistent with the health status of the udder. Finally cathepsin D played a role in the worsening of renneting properties of ewe milk.


1996 ◽  
Vol 63 (2) ◽  
pp. 269-280 ◽  
Author(s):  
Martin J. Auldist ◽  
Stephen Coats ◽  
Brian J. Sutherland ◽  
Jeffery J. Mayes ◽  
Graham H. McDowell ◽  
...  

SummaryThe effects of somatic cell count and stage of lactation on the yield and quality of Cheddar cheese were investigated. Cheese was manufactured in a pilotscale factory using milk of low bulk milk cell count (BMCC) from herds in early (LE) and late (LL) lactation, and milk of high BMCC from herds in early (HE) and late (HL) lactation. The deleterious effect of an elevated BMCC on product yield and quality in late lactation was clear. Cheese made from LL milk was significantly superior to that made from HL milk for most yield and quality characteristics measured. Stage of lactation also affected cheese yield and quality, as evidenced by the lower recovery of fat and poorer flavour score for cheese from LL milk compared with that manufactured from LE milk. The observed differences could be explained largely by differences in raw milk composition. We conclude that the effect of stage of lactation was magnified by an elevated BMCC, and that many of the problems encountered when processing late season milk could be overcome by containing mastitis at this time.


2004 ◽  
Vol 87 (3) ◽  
pp. 533-542 ◽  
Author(s):  
M. Albenzio ◽  
M. Caroprese ◽  
A. Santillo ◽  
R. Marino ◽  
L. Taibi ◽  
...  

2009 ◽  
Vol 76 (2) ◽  
pp. 195-201 ◽  
Author(s):  
Erik Wickström ◽  
Karin Persson-Waller ◽  
Helena Lindmark-Månsson ◽  
Karin Östensson ◽  
Åse Sternesjö

The somatic cell count (SCC) in bovine bulk tank milk is presently used as an indicator of raw milk quality, reflecting the udder health status of the herd. During mastitis, SCC increases, mostly owing to an influx of polymorphonuclear leucocytes (PMN) from blood into milk, with a concomitant change in milk composition. Bulk tank milk samples were categorized according to their SCC, as well as polymorphonuclear leucocyte count (PMNC), to study relationships between SCC, PMNC and various raw milk quality traits, i.e. contents of total protein, whey protein, casein, fat and lactose, casein number, proteolysis and rheological properties. The proportion of PMN, obtained by direct microscopy, was significantly higher in samples with high SCC compared with low SCC samples. SCC and PMNC were strongly correlated, yielding a correlation coefficient of 0·85. High SCC samples had lower lactose and casein contents, lower casein number and more proteolysis than low SCC samples. Samples with high PMNC had a lower casein number than low PMNC samples. Samples with high and low SCC or PMNC did not differ in respect to rheological properties. Our results do not indicate that PMNC is a better biomarker than SCC for raw bulk tank milk quality, as previously proposed.


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