Dairy industry and production systems

In October 2023, what was the estimated number of dairy producers according to AHDN, and how did this differ from the previous year?

7500

down 4.5%

what has been happening to the total UK dairy herd size?

it’s been declining

what has been happening to the number of cattle per individual dairy herd?

it’s been increasing

what age do heifers start their cycle?

around 12 months

what’s the critical factor which determines when puberty in heifers occurs?

bodyweight

what’s the ideal time to get heifers in cycle, in calf, and calving?

in cycle - 13 months,

in calf - 15 months,

calving - 24 months,

what’s the destined weight if a Holstein heifer?

600kg

what do you want a Holstein heifer to weight at 12 months and before it’s 15 months?

12 months - 300kg

15 months - put on another 60kg (so 360kg)

what’s an essential part of heifer fertility management?

measuring heifer weights and setting liveweight targets

how many days post partum does normal cycling occur?

40

what’s the major cause of failure to return to a normal cycle in heifers?

excess loss of body condition after calving

what’s the voluntary waiting period (TWP)?

around 50 days

how often do cows come into heat?

every 21 days until they become pregnant

in a 365 day calving interval, how many days does a cow need to be pregnant post-calving?

by 84 days post-calving

why is the 1st ovulation not useful for breeding management?

there are no signs of oestrus

when does second ovulation occur, what will the heifer show?

around 40 days after calving

heifer will show signs of oestrus but she’s not particularly fertile at this stage

if you want to maintain a 365 calving pattern, when must the heifer become pregnant?

on the 3rd or 4th ovulation (within the 84 days)

what is the target age for a heifers 1st calving?

2 years old

when is peak lactation?

60-90 days post calving

what happens after peak lactation?

it declines continuously until drying off

what’s the ‘rule of thumb’ for peak yield?

14d yield x 1.3

what’s the ‘rule of thumb’ for total lactation yield?

peak yield x 200

what is the definition of the voluntary waiting period?

the interval during the postpartum period where producers decide not to breed cows even if oestrus occurs

why does voluntary waiting period vary?

depending on the breeding strategy in place

what is the gestation of a cow?

280 days

on what day does drying off occur in the 365 day cycle?

day 305

what is a seasonal system reliant on?

grazed grass and conserved silage

what are input costs and output like for seasonal systems?

low

when does calving usually occur in seasonal systems?

block calving in the spring or in the autumn

what’s the supply of milk like in seasonal systems?

seasonal

what are the breeds in seasonal systems adapted to?

a high forage diet - tend to be lower yielding

what’s the typical yield of a cow in seasonal systems?

around 6000L/cow/year

what are the 5 advantages of seasonal systems?

1. lower feed costs,

2. lower disease spread,

3. less complicated feeding,

4. reduced building costs and increased flexibility,

5. less slurry

what are the 5 disadvantages of seasonal systems?

1. Holstein/high producing cows ill suited,

2. increases land requirement - limits expansion,

3. cows use energy obtaining feed,

4. uneven production cycle and quality,

5. increases parasite problem,

what’s the correlation between milk yield and fertility?

they are negatively correlated

what’s required for animals to achieve their genetic potential?

optimal health, nutrition and welfare

when does calving occur in year-round calving systems?

there’s an even spread of calving dates

what’s a year-round calving system reliant on?

conserved forage and concentrate feeds - total mixed ration (TMR)

what’s the input and output of year-round calving systems?

high

what breeds are used in year-round calving systems?

high yielding breeds (Holstein genetics)

how are year-round calving systems housed?

some are more permanently housed

what’s milk supply like in year-round calving systems?

more even throughout the year

what are 2 disadvantages of year-round calving systems?

1. expensive to set up,

2. vulnerable to increases in feed costs,

what’s the most common cattle breed in the UK, and at what %?

black and white at 89%

what are the 2 least common cattle breeds in the UK, and at what %?

Brown Swiss and Guernsey at 0.5%

what’s the fat content of milk from Jersey cows?

5%

what’s the fat content of milk from Holstein cows?

just under 4%

what’s the fat content of milk from Friesian cows?

just over 4%

how does butterfat content vary throughout the year?

ranges from 4% in the summer, up to 4.3% the rest of the year

what’s the average protein content of milk in the UK?

3.3-3.5%

what was the UK average milk price for December 2024, announced by DEFRA?

46.12ppl

in 2022, what caused an increase in milk price to ensure supplies?

inflationary pressures (due to Ukraine war, drought, labour shortages) which had led to many farmers selling cows to save on costs and so milk yield had decreased

what’s milk price determined by?

• contract type,

• seasonality,

• volume,

• fat %,

• protein %,

• Bactoscan,

• somatic cell count,

what is a bactoscan?

a measurement of the number of bacteria present in milk

what is somatic cell count a major indicator of?

milk quality

what are the 2 types of contract?

compositional and liquid

what does high bacteria levels in milk cause?

shorter shelf life and its ability to produce good quality milk

what does bactoscan indicate?

the level of bacterial contamination from external sources, such as…

• insufficient cleaning of milking equipment,

• poor udder and teat preparation prior to milking,

• high level of environmental pathogens,

what’s the legal requirement set by the EU so that milk is suitable for human consumption of milk?

currently a maximum of 100,000 cfu/ml

when are financial penalties given to producers?

when they go over the predetermined level set out in their contract

why is a low Bactoscan desirable?

it reflects good parlour management, a clean environment and low mastitis levels in the herd

why type of cells are the majority of somatic cells?

leukocytes (white blood cells)

what are epithelial cells?

milk-producing cells shed from inside the udder when infection occurs

what is somatic cell count?

the number of cells per ml of milk

what’s the SCC of an ‘uninfected cow’?

100,000 or less

what’s the threshold SCC that’s used to determine if a cow is infected with mastitis?

200,000

what SCC indicated that the cow is highly likely yo be infected on at least one teat?

greater than 200,000

what’s the SCC of cows infected with significant pathogens?

300,000 or greater

what’s the AHDB industry target for a herd-average SCC?

below 150,000 cells/ml

what’s the AHDB industry target for the average bactoscan result?

below 5000

what’s a compositional contract?

milk is used for processing into something else

what the EU milk minimum quality standards for protein?

2.8%

what the EU milk minimum quality standards for fat?

3.2%

what the EU milk minimum quality standards for bacterial plate count 30 degrees Celcius?

<100,000/ml (=500,000/ml bactoscan)

what the EU milk minimum quality standards for SCC?

not more than 400,000/ml

what the EU milk minimum quality standards for freezing point depression?

not more than -0.520 degrees celcius

what the EU milk minimum quality standards for antibiotics?

>0.004 micro grams/ml: penicillin, undetectable for others