How to ensure heifers calve down a second time

Data published earlier this year show nearly a fifth of first-time calvers do not reach a second lactation, which is costly from economic, genetic and environmental perspectives.

They also suggest that improvements can be made when it comes to the health and welfare of cows, which is key for longevity and consumer perception of the industry.

See also: 12 tips on rearing heifers to last longer

“The majority of heifers are not paying back their rearing costs until their second lactation,” says AHDB senior dairy scientist Jenny Gibbons.

She says data from the National Milk Records (NMR) 500-Herd report show 17% of animals are exiting the herd in their first lactation.

“Each cow should really be leaving the herd healthy at a pre-planned time [and] preferably not before her fifth lactation,” she adds.

“There is no clear-cut answer to achieving a successful second calving – it will vary on each farm, but by delving in and looking at heifer-only data on individual farms, it can highlight things happening in heifers and not older cows and can show weaknesses and strengths.”

Successfully getting heifers into second and subsequent lactations should:

• Recoup rearing costs
• Pay for that animal’s bed and breakfast
• Generate profit from milk sales
• Reduce the need for replacements and allow for more beef calf production
• Decrease the environmental impact through more efficient production and reduced culling.

Areas for improvement

“There is a huge array of research on calf rearing until weaning, but the research beyond that period is sparse,” says Dr Gibbons.

She adds that while focus will be needed on transition at first calving, attention is needed much earlier in life as well to produce a well-grown and robust heifer calving at 24 months.

“All of the work up to breeding, in those first 400 days, you’re setting her up to be the most productive and profitable cow you can.”

From calving onwards, there are several key areas that should be reviewed.

1. Transition stress

Reducing the risk of disease, which is exacerbated by stress, will help keep heifers healthy and get them back in-calf. Areas to look at are:

• Cubicle/parlour training before calving
• Adjustment to the dry group and new ration before calving
• Heifer-only groups/areas for a minimum of five days post-calving, preferably aiming for at least four months
• Moving heifers in pairs or groups in the afternoon when it is quieter
• Allowing enough lying/loafing/feeding space
• Assessing cow flow and checking for housing issues that could allow bullying.

2. Weight gain

“We recommend throwing a weighband around, or using scales, on your second- and third-lactation cows to work out the mature weight of your cows, and then you can work out what you should aim for,” Dr Gibbons says.

This is more accurate than working from book values because mature cow weights can vary greatly across different systems.

Target

• 1-1.2kg/day of growth in post-weaning period
• 55-60% of mature cow bodyweight by breeding
• 90% of mature cow bodyweight at first calving

3. Fertility and living space

One study looking at involuntary culls in Holstein-Friesian heifers through to third calving in England concluded that 40% of culls were due to infertility.

The NMR 500-Herd data show that 34% of milking heifers exiting the herd were served, but did not conceive. A further 38% had not been served when they exited the herd.

This could be due to a multitude of reasons, such as a submission issue if heifers are not willing to express a heat.

AHDB-funded research at the University of Nottingham showed that a first-lactation heifer allocated a larger living space (14sq m) produced 643 litres more milk over a 305-day lactation (12,235 litres) than one in the control space group (given 9sq m living space).

It also demonstrated that heifers in the group with greater living space lie down for 63 more minutes each day, without any changes to cubicles themselves, which could help prevent lameness.

Target

• Lying space of at least one cubicle a heifer or 10sq m in a loose yard

4. Lameness

The fat pad in the hoof is thinner in younger cows and thinnest at calving, so looking after hooves is paramount to decrease risk of ulcers or bruising.

Housing conditions are also key because the hormones that relax hips at calving also relax ligaments in the hoof.

If the cows’ environment means there is more perching, bullying or standing, there is a greater risk of hoof damage at this time.

One incidence of lameness increases lifetime risk of lameness, and reducing it can improve fertility. This is because a lame animal is less likely to express oestrus.

New research has shown the huge benefit of administering anti-inflammatory drugs at calving in reducing future lameness (see below).

Ultimate goals

Dr Gibbons, and Ginny Sherwin, clinical assistant professor in farm animal medicine at the University of Nottingham, have produced two key targets for farms, focusing on rearing efficiency and heifer effectiveness.

Jenny Gibbons and Ginny Sherwin are speaking at a series of AHDB meetings. “Achieving a successful 2nd lactation” meetings will be running throughout May. The list of dates and locations are on the AHDB website.