Teagasc recently held a conference detailing the latest research on milk quality related to a number of different areas including the food industry, bacterial quality, residues in milk, and somatic cell count.
International guest speaker Pamela Ruegg from Wisconsin Madison University gave a very telling synopsis of her experience dealing with somatic cell count (SCC). She started off by saying: “Keeping cell counts low is simple – you need to keep bacteria out and remember if you don’t forestrip before milking then you won’t find 50% of the problems and then dilution becomes the solution to keeping cell count low and this is not a long-term solution.”
She explained 50% of the herds in the US are using monthly milk recording and Pamela feels it is absolutely necessary to have monitoring systems. She continued by laying out the facts on what doesn’t cause high cell count: “Cell count is not affected by breed, milk yield (unless milk yield is less than 7kg per day), stage of lactation or nutritional management and finally cell count is not affected by other cow diseases.”
Many farmers try to link high cell count to breed, stage of lactation etc but from working with herds all over the world, Pamela says all these reasons are a complete myth.
So what does affect cell count? Pamela said: “Management practices are the number one influence. When you see clots in the milk it is not the start of the problem because the cow is already reacting – at that stage you have not detected the moment of infection but merely you are seeing the cow’s immune response to the problem that started a number of days previously. The message is you need to act quick when you see clots because already you are behind.”
So how can processors and farmers work better to improve milk quality – is it more of the carrot or more of the stick? Pamela used the example of the US, where the rules state that milk must be supplied from farms under 700,000 cells/ml but the federal regulation has no bearing on what the market requires. The market requires milk under 400,000 cells/ml because product sold onto the world market needs to be below 400,000 cells/ml to get an export cert from the USDA.
She said processors in Wisconsin set the limit at 250,000 cells/ml and subsequently the milk supplied dropped to 180,000 on average over the last five years.
Setting the right threshold is one of the most important issues so that processors and farmers realise when there is a problem.
OTHER POINTS
FROM PAMELA
A cow infected with Staph mastitis can go up and down in cell count on milk recording results. She said: “be aware that a cow could be 1.6 million cells/ml in one recording and then go down as low as 200,000 cells in the next recording but the cow is still chronically infected. Have a plan in place not a ‘response’ – once mastitis develops you’ve lost the battle. Make sure it’s a monthly/quarterly/annual mastitis plan so that it’s monitored constantly – you won’t make progress without deadlines and actions.Q&A: Are milking robots producing more quality milk? – “I’ve studied both conventional and robot parlours and the very same problems exist in both. There is really nothing different and the same principles apply to both.Q&A: Should you sanitise clusters between cows? “Three studies on automated backflush in Canada followed for a long term showed it had an impact on new infection rate but that it took 12 months. It might be a strategy if there is a very high proportion of infected cows.Infant formula – quality essential
Moorepark food researcher Mark Fenelon discussed the importance of milk quality for the infant formula industry.
He said: “The primary objective of any infant formula manufacturer is to produce products which adhere to the highest quality standards as they are feeding babies who are only building up immunity.
“Since dairy-based ingredients are used in most infant formulations, the overall quality of the milk from which these ingredients are derived is of significant importance.
“From the perspective of the infant formula manufacturer, quality embraces compositional variations, microbiology, residues and contaminants as they affect not alone milk but also milk ingredients used in making baby powder such as skim and whey powders. Quality is only as good as the weakest link and all links need to be of the highest quality.”
Mark said milk protein is vital as it has a dual role in that it forms a nutritional base and is also responsible for giving products stability throughout processing. Proteins are key emulsifiers and their interactions with minerals largely control thermal stability of formulations.
There are multiple parameters to be realised while identifying the quality attributes needed for selection of milk for manufacturing infant formula and these include preservation of key nutritional benefits and ensuring optimised physical stability in both liquid concentrate and finished powder.
Cheese – where next?
Diarmuid Sheehan of Teagasc Moorepark explained that while cheese offers vital market opportunities post 2015 for extra product, traditional cheese markets such as cheddar are predicted to grow slower than other semi-soft and semi-hard cheese types.
Hence Diarmuid’s research and innovation is more focused on development of new products with specific properties for different target markets. This innovation is best illustrated by the current Teagasc/Irish Dairy Board collaboration.
One person in the audience asked Diarmuid was diversification in cheese, away from cheddar, the same issue that was present 30 years ago, wince when little has changed.
Diarmuid said that maybe it is the same issue but that the abolition of quota makes more milk available to make more of these new cheeses for different markets and that processors will respond to new opportunities as they arise and that cheddar and particularly whey (by product of cheese making) has delivered solid returns for the last number of years.
Iodine teat dips
If you teat dip with iodine can it increase iodine levels in milk? This was one of the questions Bernadette O’Brien set out to answer in a small field trial. She presented her results at the milk quality conference.
Iodine is fed in meal and also used in teat sprays at farm level in the expectation of increasing cow health and fertility. There is concern that such practises may result in high milk iodine, which could affect ingredients for infant formula and, thus, dairy export markets.
Lactating cows
Thirty lactating cows were fed 7kg, 3kg and 0kg of concentrate feed during three periods of 35 days each. In each kilo of feed there was 10mg iodine – this supplied feed-based iodine.
During the first 14 days of each period, cows were on feed iodine treatments only; during days 15-21, one of three teat disinfection treatments was applied, in addition to the feed iodine. The post-milking teat sprays were: (1) non-iodine (chlorhexidine); (2) 0.5% iodine spray; and (3) 0.5% iodine spray pre- and post-milking.
Cow milk yield was 21.3 kg/day. Individual cow milk samples were analysed for iodine concentration for two days at the end of each treatment period. Feed iodine at both 30mg and 70mg per day increased milk iodine concentrations significantly (P<0.001) from 155 to 474 and 511µg/kg, respectively.
Teat disinfection
Teat disinfection both pre and post milking increased milk iodine concentration at each of the feed levels of 0, 30 and 70 mg/day compared with a non-iodine teat disinfectant (P<0.001).
In conclusion, both dietary iodine supplementation and teat disinfection iodine increased milk iodine concentrations in an additive manner, exceeding common target values of 250 µg/kg. As both iodine treatments can occur simultaneously on farm, supplementation strategies should be monitored.
Dosing for fluke during lactation
Clare Power researched flukicide residues in milk if animals are improperly treated or if withdrawal periods not properly observed.
She looked at the results of studies on depletion of flukicides from milk and the transfer of flukicide residues to dairy products, if present in the milk.
She concluded that the depletion of flukicide residues from milk of animals treated during lactation is relatively slow, so the dry period (when milk is not being used for human consumption) is the most suitable time for flukicide treatment.
Migration of residues to product occurred at different rates, depending on the drug in question.
Generally, concentration of flukicides occurred in cheese, butter and skim milk powder.
Pasteurisation or heat treatment during spray drying had no impact in reducing residues.
Teagasc recently held a conference detailing the latest research on milk quality related to a number of different areas including the food industry, bacterial quality, residues in milk, and somatic cell count.
International guest speaker Pamela Ruegg from Wisconsin Madison University gave a very telling synopsis of her experience dealing with somatic cell count (SCC). She started off by saying: “Keeping cell counts low is simple – you need to keep bacteria out and remember if you don’t forestrip before milking then you won’t find 50% of the problems and then dilution becomes the solution to keeping cell count low and this is not a long-term solution.”
She explained 50% of the herds in the US are using monthly milk recording and Pamela feels it is absolutely necessary to have monitoring systems. She continued by laying out the facts on what doesn’t cause high cell count: “Cell count is not affected by breed, milk yield (unless milk yield is less than 7kg per day), stage of lactation or nutritional management and finally cell count is not affected by other cow diseases.”
Many farmers try to link high cell count to breed, stage of lactation etc but from working with herds all over the world, Pamela says all these reasons are a complete myth.
So what does affect cell count? Pamela said: “Management practices are the number one influence. When you see clots in the milk it is not the start of the problem because the cow is already reacting – at that stage you have not detected the moment of infection but merely you are seeing the cow’s immune response to the problem that started a number of days previously. The message is you need to act quick when you see clots because already you are behind.”
So how can processors and farmers work better to improve milk quality – is it more of the carrot or more of the stick? Pamela used the example of the US, where the rules state that milk must be supplied from farms under 700,000 cells/ml but the federal regulation has no bearing on what the market requires. The market requires milk under 400,000 cells/ml because product sold onto the world market needs to be below 400,000 cells/ml to get an export cert from the USDA.
She said processors in Wisconsin set the limit at 250,000 cells/ml and subsequently the milk supplied dropped to 180,000 on average over the last five years.
Setting the right threshold is one of the most important issues so that processors and farmers realise when there is a problem.
OTHER POINTS
FROM PAMELA
A cow infected with Staph mastitis can go up and down in cell count on milk recording results. She said: “be aware that a cow could be 1.6 million cells/ml in one recording and then go down as low as 200,000 cells in the next recording but the cow is still chronically infected. Have a plan in place not a ‘response’ – once mastitis develops you’ve lost the battle. Make sure it’s a monthly/quarterly/annual mastitis plan so that it’s monitored constantly – you won’t make progress without deadlines and actions.Q&A: Are milking robots producing more quality milk? – “I’ve studied both conventional and robot parlours and the very same problems exist in both. There is really nothing different and the same principles apply to both.Q&A: Should you sanitise clusters between cows? “Three studies on automated backflush in Canada followed for a long term showed it had an impact on new infection rate but that it took 12 months. It might be a strategy if there is a very high proportion of infected cows.Infant formula – quality essential
Moorepark food researcher Mark Fenelon discussed the importance of milk quality for the infant formula industry.
He said: “The primary objective of any infant formula manufacturer is to produce products which adhere to the highest quality standards as they are feeding babies who are only building up immunity.
“Since dairy-based ingredients are used in most infant formulations, the overall quality of the milk from which these ingredients are derived is of significant importance.
“From the perspective of the infant formula manufacturer, quality embraces compositional variations, microbiology, residues and contaminants as they affect not alone milk but also milk ingredients used in making baby powder such as skim and whey powders. Quality is only as good as the weakest link and all links need to be of the highest quality.”
Mark said milk protein is vital as it has a dual role in that it forms a nutritional base and is also responsible for giving products stability throughout processing. Proteins are key emulsifiers and their interactions with minerals largely control thermal stability of formulations.
There are multiple parameters to be realised while identifying the quality attributes needed for selection of milk for manufacturing infant formula and these include preservation of key nutritional benefits and ensuring optimised physical stability in both liquid concentrate and finished powder.
Cheese – where next?
Diarmuid Sheehan of Teagasc Moorepark explained that while cheese offers vital market opportunities post 2015 for extra product, traditional cheese markets such as cheddar are predicted to grow slower than other semi-soft and semi-hard cheese types.
Hence Diarmuid’s research and innovation is more focused on development of new products with specific properties for different target markets. This innovation is best illustrated by the current Teagasc/Irish Dairy Board collaboration.
One person in the audience asked Diarmuid was diversification in cheese, away from cheddar, the same issue that was present 30 years ago, wince when little has changed.
Diarmuid said that maybe it is the same issue but that the abolition of quota makes more milk available to make more of these new cheeses for different markets and that processors will respond to new opportunities as they arise and that cheddar and particularly whey (by product of cheese making) has delivered solid returns for the last number of years.
Iodine teat dips
If you teat dip with iodine can it increase iodine levels in milk? This was one of the questions Bernadette O’Brien set out to answer in a small field trial. She presented her results at the milk quality conference.
Iodine is fed in meal and also used in teat sprays at farm level in the expectation of increasing cow health and fertility. There is concern that such practises may result in high milk iodine, which could affect ingredients for infant formula and, thus, dairy export markets.
Lactating cows
Thirty lactating cows were fed 7kg, 3kg and 0kg of concentrate feed during three periods of 35 days each. In each kilo of feed there was 10mg iodine – this supplied feed-based iodine.
During the first 14 days of each period, cows were on feed iodine treatments only; during days 15-21, one of three teat disinfection treatments was applied, in addition to the feed iodine. The post-milking teat sprays were: (1) non-iodine (chlorhexidine); (2) 0.5% iodine spray; and (3) 0.5% iodine spray pre- and post-milking.
Cow milk yield was 21.3 kg/day. Individual cow milk samples were analysed for iodine concentration for two days at the end of each treatment period. Feed iodine at both 30mg and 70mg per day increased milk iodine concentrations significantly (P<0.001) from 155 to 474 and 511µg/kg, respectively.
Teat disinfection
Teat disinfection both pre and post milking increased milk iodine concentration at each of the feed levels of 0, 30 and 70 mg/day compared with a non-iodine teat disinfectant (P<0.001).
In conclusion, both dietary iodine supplementation and teat disinfection iodine increased milk iodine concentrations in an additive manner, exceeding common target values of 250 µg/kg. As both iodine treatments can occur simultaneously on farm, supplementation strategies should be monitored.
Dosing for fluke during lactation
Clare Power researched flukicide residues in milk if animals are improperly treated or if withdrawal periods not properly observed.
She looked at the results of studies on depletion of flukicides from milk and the transfer of flukicide residues to dairy products, if present in the milk.
She concluded that the depletion of flukicide residues from milk of animals treated during lactation is relatively slow, so the dry period (when milk is not being used for human consumption) is the most suitable time for flukicide treatment.
Migration of residues to product occurred at different rates, depending on the drug in question.
Generally, concentration of flukicides occurred in cheese, butter and skim milk powder.
Pasteurisation or heat treatment during spray drying had no impact in reducing residues.
This is a subscriber-only article
SHARING OPTIONS: