Early Lactation Feeding:
Nutrition and Maximising Fertility Performance
Early Lactation Feeding:
Nutrition and Maximising Fertility Performance

Poor fertility performance is the biggest cause of involuntary culling on Irish dairy farms.  Reducing empty rates from 15% to 10% will yield a return of 1c/ltr net margin.  For good fertility performance you need;

- An optimum breeding management programme, 

- A feeding programme appropriate for your cow,  

- A good herd health status 

- An AI programme that breeds for fertility

 

Key Point:Fertility performance is a product of submission rate and conception rate 

Submission rates is influenced by 

- Healthy wombs

Difficult calving or poor hygiene in the calving box can cause infection in the cows’ womb.  This needs to be treated appropriately and any cow not bulling by day 40 after calving needs to be checked by the vet.  

Key Point: Correct mineral and vitamin nutrition, especially selenium and vitamin E has been shown to have a positive effect on healthy wombs. 

- Early return to cycling/ heat

Cows calving down in poor BCS had a longer calving to first service and a longer calving to conception interval than cows calving down with a greater BCS.

- Heat detection

All farmers should use tail-painting and/or visually inspection their herd 4 times a day for 20 minutes duration.

Conception rate is influenced by:

- Energy Nutrition 

- Disease

- Protein Nutrition

- Mineral nutrition

Energy Nutrition (Negative Energy Balance (NEB) post calving).

Key Point: Energy intake is king. 

Negative energy balance and some BCS loss after calving is inevitable, as a cows’ maximum energy output in milk occurs before her maximum dry matter intake (DMI) is reached.  

Our job is the limit the amount of BCS loss by maximising energy intake.  This is achieved by prioritising the feeding of high energy feeds (grass, high quality silages and concentrates) and by ensuring the cows maximum DMI is achieved.  

Key Point: Minimising NEB will lead to higher milk solids, a smaller level of BCS loss after calving, and an overall better fertility performance

At herd level the first sign of NEB is low milk protein % and a high milk fat to protein ratio (ketosis). 

Relationship bewteen BCS loss post calving and 6 week Incalf Rate (for cows with a pre-calving BCS of >3) (Teagasc Trail 1999).

Key Point: It is an absolute necessity that we know the energy requirement of the dairy cow and that we feed to meet this requirement.  

Energy requirement of the milking cow:

Maximising Energy Intake

Energy intake is a function of the cows dry matter intake (DMI) times the energy density of the diet. 

Indoor intake can vary between 3-4% of body weight or between 18 – 24kg DM, but with irish quality forages it usually between 18-20kg DM. 

We need to target an energy density of between 0.90 -0.95 UFL per kg in the total diet for higher yielding herds, but with poor quality silage it can be as low as 0.85 UFL/kg. 

What affect Dry Matter intake;

- Dry matter, 20% DM silage having a lower intake potential than 25% DM

- Dry matter digestibility, 65% DMD silage having a lower intake potential than 75% DM

- pH and Ammonia, with poorly preserved silages having a lower potential intake than well preserved silages

- 1 forage or 2, grass silage only diets have a lower forage intake potential than grass silage + maize/wholecrop/fodder beet.

What affects Energy Density

In simple terms the more digestible the feed the more energy dense it is.

Effect of DMI on milk carrying capacity of the diet  

Effect of energy density on milk carrying capacity of the diet 

Key point:  High intake of low energy feeds can = low energy intake

Low intake of high energy feeds can = low energy intake

But worse still is 

Low intake of low energy feed (Low DMD silage without sufficient concentrates) = INFERTILITY

Winter milk and grazing

Heavy autumn grass (>1700kgDM) does not work for freshly calved cows and is best avoided. Grazing heavier covers leads to poor utilisation, especially if buffer feeding. Where >50% of the herd is autumn calving, do not build grass covers in September. Instead aim to graze off the farm by early November and focus on early turnout to extend the grazing season.   

Key Point: Keep good quality grass in the diet as long as possible.  This will up the energy intake of your cows and lower your concentrate requirement.     

 

Rumen Function

 

If your not making milk your making expensive manure. 

Poor rumen function leads to undigested feed being passed out in the dung. We need to maximise rumen function by;

- Not over feeding starch and sugar, 

- Feeding sufficient effective fibre,

- Keeping the rumen well buffered with products such as yea-sacc. 

Protein Nutrition:

Key Point: The amount of crude protein that a cow can turn into milk protein is a function of the energy she is fed.  Dietary protein levels should be a function of the energy density of the diet.

 

 

Feeding excess protein to energy leads to high milk urea nitrogen and has been shown to ;

- delay first ovulation or oestrus; 

- lower reduce conception rate and 

- lead to a greater amount of post calving weight loss. 

 

 

Protein requirements of a dairy cow (450kg MS or 6000ltrs) at peak yield is 95 to 105g PDI/KG DM (1800-2000 g PDI/day) or 16 % crude protein.  

 

 

Mineral Nutrition:

 

Grass silage is a suboptimal trace element source for dairy cows, deficiencies of copper, selenium and iodine are widespread. Isolated deficiencies in manganese, zinc and cobalt also exist.  

Grass silage as a mineral source for dairy cows (100% = daily requirement)

Mineral interactions within grass silage can results in induced or secondary deficiency e.g molybdenum and sulphur cause copper deficiency.  

 

Dietary deficiencies of copper, selenium and iodine are linked to:

- poor fertility, 

- cystic ovaries, 

- anoestrous, 

- irregular or supressed oestrus 

- and early embryonic death.

 

Trace mineral requirements of a dairy cow

Key Point: It is extremely important to ensure that the inclusion level of the mineral in a concentrate match the concentrate feeding level. 

If the concentrate is formulated at 4 kg but your only feeding 2.5 kg of a concentrate the dairy cow will not be getting the correct mineral levels.  

 

The mineral form is also important. 

Key Point: Bioplex or organic  minerals are not tied up by mineral interactions, therefore ensuring they are available to the cow.  

 

Availability of different mineral sources

The concentrate should contain adequate levels of bioplex copper, selenium and zinc to ensure fertility performance is maximised.  

Dairygold feed range address all the issues. 

Benefits of Dairygold feed range;

1. High energy, with high levels of bypass starch coming from maize meal and a blend of high energy digestible fibre resulting in good rumen function and maximum milk yield and protein %.  

2. Only good quality protein used, leading to high levels of PDI, good protein efficiency, maximum yield and protein %

3. Yea-sacc inclusion to aid rumen function and efficiency leading to lower levels of digestive upset and higher milk volume

4. Bioplex copper, zinc and seplex included for better fertility performance, lower SCC and mastitis and less lameness

5. Elevated levels of Vitamin E, which works with seplex to boost the cows immune function leading to lower SCC and mastitis. 

Get in touch 

For further help and advice contact your local Agri representative

Meet all our representatives