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- Forsbäck, Linda, et al.
(författare)
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Day-to-day variation in milk yield and milk composition at udder quarter level
- 2010
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Ingår i: Journal of Dairy Science. - : American Dairy Science Association. - 0022-0302 .- 1525-3198. ; 93, s. 3569-3577
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Tidskriftsartikel (refereegranskat)abstract
- Automatic in-line measurement of milk composition and milk yield could be a useful tool in management of the dairy herd. Data on milk components and milk yield provide information on milk quality alterations and cow health status but are also useful in planning feeding and breeding. In automatic milking systems, udder quarters are milked individually, enabling analysis and recording at the udder-quarter level. Frequent records of components require knowledge about day-today variations. A component with greater day-to-day variation needs more frequent sampling when used as a diagnostic tool and for management decisions. Earlier studies have described the day-to-day variations in milk components for cow composite milk, but with the quarter milking technique and the possible sampling at the udder-quarter level, knowledge about day-to-day variations at the udder-quarter level is needed. In this study, udder-quarter and cow composite milk samples were collected from 42 consecutive milkings of 10 cows during 21 d. Milk yield was recorded and the milk was analyzed for total protein, whey protein, casein, fat, lactose, and somatic cell count. The results showed that the day-to-day variations and mean values for 4 healthy udder quarters within a cow were similar. In addition, different milk components had different levels of day-to-day variation, the least variation being found in lactose (0.9%) and the greatest in fat (7.7%). This suggests that repeated milk sampling and analysis at the udder-quarter level can be used to detect alterations in composition and cow health and would, thus, be helpful in the management of the dairy herd.
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| 4. |
- Forsbäck, Linda, et al.
(författare)
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Evaluation of quality changes in udder quarter milk from cows with low-to-moderate somatic cell counts
- 2010
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 4, s. 617-626
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Tidskriftsartikel (refereegranskat)abstract
- Much emphasis has been put on evaluating alterations in milk composition caused by clinical and subclinical mastitis. However, little is known about changes in milk composition during subclinical mastitis in individual udder quarters with a low-to-moderate increase in milk somatic cell count (SCC). This information is needed to decide whether milk from individual udder quarters with a moderate-to-high increase in milk SCC should be separated or not. The aim of this study was to determine how milk composition in separate udder quarters is affected when cow composite milk has low or moderately increased SCC levels. Udder quarter and cow composite milk samples were collected from 17 cows on one occasion. Milk yield was registered and samples were analyzed for SCC, fat, total protein, whey proteins, lactose, citric acid, non-protein nitrogen (NPN), lactoferrin, protein profile, free fatty acids (FFAs), lactate dehydrogenase (LDH), proteolysis, sodium and potassium. Bacteriological samples were collected twice from all four quarters of all cows. The cows were divided into three groups depending on their SCC at udder quarter level. The first group comprised healthy cows with four udder quarters with low SCC, < 50 000 cells/ml; composition was equal when opposite rear and front quarters were compared. In the second and the third groups, cows had one udder quarter with 101 000 cells/ml < SCC < 600 000 cells/ml and SCC > 700 000 cells/ml, respectively The remaining udder quarters of these cows had low SCC (<100 000 cells/ml). Despite the relatively low average cow composite SCC = 100 000 cells/ml of Group 2, milk from affected udder quarters exhibited lower casein number, content of lactose and beta-casein (beta-CN, while the content of whey protein, sodium, LDH and (alpha-lactoalbumin (alpha-la) were higher compared to healthy opposite quarters. In addition to these changes, milk from affected udder quarters in Group 3 also exhibited lower values of potassium and alpha(s1)-casein (alpha(s1)-CN) and higher values of lactoferrin when compared to milk from opposite healthy quarters. This indicates that even when the SCC in cow composite milk is low, there might exist individual quarters for which milk composition is changed and milk quality impaired.
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| 7. |
- Forsbäck, Linda, et al.
(författare)
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Udder quarter milk composition at different levels of somatic cell count in cow composite milk
- 2009
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Ingår i: Animal. - 1751-7311 .- 1751-732X. ; 3, s. 710-717
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Tidskriftsartikel (refereegranskat)abstract
- Automatic milking systems have made possible the separation of high- and low-quality milk at the udder quarter level during the milking process. The aim of this study was to investigate the composition and yield of milk from individual udder quarters to determine whether deteriorated milk composition occurs in udders that are assumed to be healthy and whether quarters with high-quality milk are found in udders with high milk somatic cell count (SCC). Milk samples were collected on one occasion from 90 cows at udder quarter level and cow composite level. The milk was analyzed for content of total protein, whey protein, casein, fat, lactose, citric acid and SCC; milk yield was registered. The cows were divided into three groups depending on the SCC of their composite milk. Cows in group 1, cow composite SCC<100 000 cells/ml were assumed to have healthy udders. However instances of increased SCC and decreased milk quality were discovered in one or more udder quarters of approximately 30% of the group. Cows in group 2, cow composite SCC of 100 000 to 300 000 cells/ml, and group 3, cow composite SCC>300 000 cells/ml, were assumed to have affected udders. However, the majority of these cows had one or more udder quarters in which increased SCC and deteriorated milk quality were not detected. Calculations of bulk-tank milk values, when separation of milk from affected udder quarters was performed, indicate that SCC changes to a much greater degree compared to the other milk components. These results show that milk from affected udder quarters suffers compositional changes, but calculations of simulated separation indicate that the compositional changes in bulk-tank milk are small. The effect of separation of milk from individual udder quarters on bulk-tank milk needs to be further studied.
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| 8. |
- Fröberg, Sofie, et al.
(författare)
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Performance of free suckling dairy calves in an automatic milking system and their behaviour at weaning
- 2011
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Ingår i: Acta Agriculturae Scandinavica, Section A - Animal Science. - : Informa UK Limited. - 0906-4702 .- 1651-1972. ; 61, s. 145-156
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Tidskriftsartikel (refereegranskat)abstract
- The performance of dairy calves allowed to suckle freely (FS) until eight weeks of age in a cubicle system with automatic milking was compared to automatic teat-feeding with low milk (LM) or high milk (HM) substitute allowances. Weight gain and feed intake of FS (n = 13), LM (n = 23) and HM (n = 22) calves were recorded until two weeks after abrupt weaning, and their behaviour was studied during weaning. FS calves had higher weight gain, but much lower solid feed intake until weaning, than LM and HM calves and their advantage in weight remained throughout the study despite very low post-weaning gain. During the first 24 hours after weaning, FS calves displayed more behavioural signs of stress. However, at 72 hours after weaning, behaviour was similar for all treatments. Methods to stimulate solid feed intake before weaning need to be developed to draw advantage of the FS system.
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| 9. |
- Lakic, Branislav, et al.
(författare)
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Is there a special mechanism behind the changes in somatic cell and polymorphonuclear leukocyte counts, and composition of milk after a single prolonged milking interval in cows?
- 2009
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Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 51, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Background: A single prolonged milking interval (PMI) e.g. after a technical stop in an automatedmilking system is of concern for the producer since it is associated with a short-lasting increase inmilk somatic cell count (SCC), which is a major quality criterion used at the dairy plants. Thecontent of polymorphonuclear leukocytes (PMN) and how the milk quality is influenced has notbeen much investigated. The SCC peak occurs without any obvious antigen challenge, possiblyindicating a different leukocyte attraction mechanism after a PMI than we see during mastitis.Methods: Composite cow milk samples were taken at the milkings twice daily during 7 days beforeand 5 days after a PMI of 24 h. Milk was analyzed for SCC, PMN, fat, protein and lactose, and atsome occasions also casein and free fatty acids (FFA).Results: During the PMI the proportion of milk PMN increased sharply in spite of marginallyincreased SCC. The peak SCC was not observed until the second milking after the PMI, in theafternoon day 1. However, the peak SCC value in morning milk did not occur until one day later,concomitantly with a decrease in the proportion of PMN. After declining, SCC still remainedelevated while PMN proportion was decreased throughout the study as was also the milk yield,after the first accumulation of milk during the PMI. Milk composition was changed the day after thePMI, (increased fat and protein content; decreased lactose, whey protein and FFA content) but thechanges in the following days were not consistent except for lactose that remained decreased therest of the study.Conclusion: The PMI resulted in increased SCC and proportion of PMN. Additionally, it gave riseto minor alterations in the milk composition in the following milkings but no adverse effect on milkquality was observed. The recruitment of PMN, which was further enhanced the first day after thePMI, appeared to be independent of milk volume or accumulation of milk per se. Hence, we suggestthat there is a special immunophysiological/chemoattractant background to the increased migrationof leukocytes into the milk compartment observed during and after the PMI.
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| 10. |
- Lakic, Branislav, et al.
(författare)
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The effect of a single prolonged milking interval on inflammatory parameters, milk composition and yield in dairy cows
- 2011
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Ingår i: Veterinary Immunology and Immunopathology. - : Elsevier BV. - 0165-2427 .- 1873-2534. ; 140, s. 110-118
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Tidskriftsartikel (refereegranskat)abstract
- A technical stop in automatic milking systems may result in a severely prolonged milking interval (PMI) with subsequent impact on milk somatic cell count (SCC). This study investigated the inflammatory reaction, milk composition and yield during SCC peak observed in composite milk after exposing cows to a single PMI of 24h. At the first milking after the PMI, a sharply increased proportion of milk polymorphonuclear leukocytes (PMN) but marginally increased SCC were observed. The peak in SCC was not seen until morning milking day 2 after the PMI, notably, concomitantly with a decreased PMN proportion. An increase in blood lactose, milk bovine serum albumin and serum amyloid A (SAA) and a drop in milk alpha lactalbumin (ALA) were seen concomitantly with the peak in PMN. All parameters mentioned, had returned to base line after day 2. The changes in SCC and SAA had the longest duration. Lactate dehydrogenase in afternoon milk was decreased during the whole study as was also afternoon milk yield. Interleukin-1 beta could not be detected in milk at any time. SAA and ALA, respectively, may influence chemotaxis and the changed concentrations observed after the PMI might have contributed to the increased migration of PMN to milk. (C) 2010 Elsevier B.V. All rights reserved.
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