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May 2015

on .


  • To make money in 2016, you must be on the 'fertility ball' for the next two months;
  • Quality grass yields profit;
  • Round bale surpluses from paddocks, and top if too many dung pads;
  • You should have more than 64 per cent of your year's nitrogen (N) used by the end of May;
  • No 12-hour grazing blocks;
  • Preventative healthcare is best and cheapest;
  • Use 1.5 to 2 artificial insemination (AI) straws per
  • cow in the herd;
  • Get 'a spoonful of sugar' from after-evening-tea grass.

Matt Ryan
Fertility targets
This month is the driver of dairy farmers' most important key performer index (KPI) for 2016: the six-week calving rate. It is vital that dairy farmers know what they have to achieve during the breeding season. The following targets must be the goal:
Submission rate (three week) – 90 per cent;
Conception rate to first service – 65 per cent;
42-day in-calf rate: (a) cows – 85 per cent; (b) heifers – 95 per cent;
Services per conception – 1.7 per cent;
Infertile rate – 10 per cent;
Herd calving interval (days) – 365; and
AI/bull/scanning/drugs costs – 0.8 cents/litre.

You can't measure these unless you have good records:
Use the breeding chart and pocket notebook to record all breeding details;
Use Irish Cattle Breeding Federation (ICBF) HerdPlus data from last year to establish where you are weak, and use it this year to stay on top of problems arising.
A missed heat = loss of €250 per cow
It can be as many as 30 per 100-cow herd, which is a loss of €7,500. This happens if the farmer is not geared up for identifying bulling cows. It's all about submission rates. The conception rate for a 13-week breeding season will be the same in the following two scenarios: a 90 per cent heat detection rate with a 30 per cent conception rate; and a 50 per cent heat detection rate with a 60 per cent conception rate.
The key factors driving the six-week calving rate are:
Herds' calving pattern – late calving cows have a negative effect (in Ireland, 33 per cent of spring calving cows calve after April 1);
The percentage of cows with low body condition at calving (far too high) and loss of body condition score (BCS) from calving to service (thin cows would respond to once-a-day [OAD] milking now);
The standard of heifer rearing (poor at present in Ireland);
The ability of the AI technician and his care of handling the semen;
Heat detection efficiency;
Bull management post-AI, with too few bulls or the bull becoming sick/injured;
Individual cows' percentage protein relative to the herd, because high-protein cows have better conception rates,

Heat detection aids are essential, and any dairy farmer who is using AI has no chance of identifying all bulling cows without them. You must believe in these:
If all paint is removed, then there is a 93 per cent chance the cow is bulling;
Even if as little as 25 per cent of the paint is removed, there is a 76 per cent chance she is bulling;
The secret is that the paint should be only two inches wide and 9-10 inches long;
Quickly check the other signs to confirm;
These heat detection aids must be used continuously on all cows during May and June.

As most farmers are relying almost solely on such aids, it is imperative that the farmer spends sufficient time picking out cows that indicate they are 'on-heat'.
This is not done adequately on farms. Farmers should observe the cows entering the collection yard, or while they are in the parlour, either with mirrors or by stepping up onto the kerb in order to be at same level as the cows' back. If you have a vasectomised bull, one per 20-30 cows, let him into the herd five to six weeks after the start of mating date.
In relation to on-the-day management, having identified the cow on heat, it makes no sense that you would mismanage her or the situation before, during or after service, resulting in poor conception rate. What could you do wrong?
You could allow the cow to be stressed by: lack of feed or water; being too long in the crush; being bullied by dominant cows; or being intimidated by dogs, cats or humans;
The DIY operator, or technician, could also mishandle the AI straw or the service actions:
The straw should be stored hygienically in a plastic glove, thawed out completely and used within five minutes of thawing;
The straw should be handled carefully and hygienically;
If, as a DIY operator, you have the slightest doubt about your ability, get a one-day refresher course or use a technician;
If you think the technician isn't operating to protocols, remind him because the financial loss to you will be massive.

The optimum time to serve cows is 12-24 hours after the onset of standing heat. To meet this requirement, it may be necessary to AI cows in the morning and again in the evening, instead of once per day. It also allows DIY operators the task of serving reasonable numbers at each AI session – too many farmers say they get tired after 10-13 cows.
If a cow has blood on her vagina/tail area, it indicates you 'missed her'. As there is only a 7 per cent chance she will go in-calf, don't AI. Use the info to get it right next time:
Write in your book that she is expected to come on heat in 18 days' time; or
Inject her with prostaglandin (PG) so that she comes on heat within a week or so;
If you have served her and there is blood there, don't PG her as she could be in-calf.

You should use a minimum of 1.5 to 2 AI Friesian straws per cow this year. For every 50 cows, use 75 AI straws. It is a very simple way of planning and knowing you will have adequate replacements in two to three years' time. If you are planning to expand, you must use two straws for every cow in the herd, or 100 AI straws per 50 cows. That means all the heifers must be artificially inseminated once.
Farmers who are serious about expansion and have the scope should use nothing else but Friesian AI on all cows:
See the updated bull list on the ICBF website;
Don't be afraid to use Jersey on high-yielding, infertile Holsteins, as it will increase the profit of the progeny by €180 per cow;
Keep focused on using highest Economic Breeding Index (EBI) bulls, with over €100 of the EBI coming from fertility and that improves protein by at least 0.10 per cent;
The 'mop-up' stock bull must be checked for fertility and ability to 'do the job' now;
Hand mate each stock bull you have now, with with three to four cows you are not using for replacement heifers. In three weeks' time, if greater than 50 per cent repeat, you know the bull is in trouble;
Remember, one in 10 bulls is infertile, while one in three becomes infertile at some stage during the season;
At a recent discussion group, one farmer admitted that he has 22 cows to calve in late June/July due to his stock bull's problems last year. This is a significant loss of milk – he is now having to sell off these cows.
Round bale surplus
Quality grass is grass that has more than 80 per cent dry matter digestibility (DMD) and is necessary to maximise milk yield and percentage protein from cows.
The quality of grazed grass is totally dependent on grazing grass that is the correct height (pre-grazing cover) for each individual farmer's stocking rate;
Tight grazing (4-4.5cm), especially early in the season, can prevent the build-up of tall grass areas in paddocks. But this can result in decreased milk production if not well managed;
When surpluses do arise, as they will, they should be taken out as round bales and fed back again to cows later in the year when grass becomes scarce. But, even with this principle, topping will be necessary and it should be done early in May rather than later;
Topping must be carried out when the 'tall grass' areas are greater than 25 per cent of the paddock area;
If the tall grass area is 25 per cent in May, it will be 35-40 per cent of the paddock in June because of the fresh dung deposited during this grazing. Tall grass is grass around dung pads and other under-grazed areas. It will be getting nitrogen and will not be eaten – imagine the financial loss from this;
But topping costs money, in terms of machinery, wear and tear, diesel and, most critically, your time and grass lost to rotting. So make it count;
Set the topper at 5cm (2.5 inches) off the ground and ensure that the blades are sharp;
Many farmers don't start topping early enough so the message is to ensure that you start in time – even early May;
New Zealand experimental work has shown that topping is preferable to pre-mowing;
Keep the benefits in mind. There is a potential extra 100 gallons of milk per cow, free of charge, if grass quality can be maintained at a high level during April-September.

Remember, topping will not be necessary if you graze tightly and graze at the correct farm cover for your stocking rate. Hence, the use of the grass wedge will save you topping money/time and ensure quality grass. For example:
At a stocking rate of 3.5 cows/ha, the target pre-grazing cover is: stocking rate x allowance x rotation length + residual, ie. 3.5x18x21+100 = 1,496kgDM/ha;
The target pre-grazing yields increase as the stocking rate increases (and declines as it falls);
You must also watch your average farm covers. The target figure is 170-200kgDM/LU. For example, at a stocking rate of 3.5 cows/ha, the target average cover, with good grazing management, would be: stocking rate x 180 = 3.5x180 = 630kgDM/ha.
64 per cent N used by May 31
You won't grow enough grass if you don't have 64 per cent of your year's N allowance used by the end of May and 76 per cent used by mid-June, because there are only three applications left for the remainder of the year. For most highly stocked farms where they are allowed to use 226 units/acre, they should have 144 units applied by mid-May and 172 before mid-June. This is the month to use N:
Growth rates and responses (1kg N, costing €1.15, will grow 25kg DM grass, worth €50 in milk) are best;
This will enable you get most of your winter feed in the first cut (cheapest by far);
You must use N appropriate for your stocking rate (see Table 1);
If you use too much you will have none left for the remainder of the year and be in trouble with the nitrates directive.

Stocking rate Fertiliser (N)
April/May May June
(acre/LU) (LU/ha) (Units N/acre) (Units N/acre)
>0.71 <3.45 14 0-14
0.67-0.71 3.45-3.7 21 14
0.63-0.67 3.7-3.95 28 21
0.59-0.63 3.95-4.25 35 28
0.55-0.59 4.25-4.45 42 35
<0.55 >4.45 42 42

Table 1: Fertiliser N for stocking rates on the grazing area during May and June.
James Humphreys (Teagasc, Moorepark) has indicated that there is no significant difference in annual grass yield, or annual milk yield (unpublished work), when N is bulk spread once per month compared to spreading after every grazing. On light soils deficient in sulphur (S), you will grow more grass (10-50 per cent, based on research). With no restriction in the use of S, you must use 20-30 units of S from now to the end of the season. If using S on copper-deficient or molybdenum-antagonised deficiency, make sure to give animals a copper bolus.
Forget 12-hour grazing
Some farmers think that this is a good idea and necessary. It is not. It is an unnecessary workload for no gain – in fact, it incurs losses. What happens is that the space the cows have to feed in is too small.
This results in the 'bully' cows chastising the timid cows, resulting in the latter having to stop grazing and move away, thus reducing their grazing time. Heifers and shy feeders suffer due to this bullying.
High-performing cows also suffer because they have to eat more grass to produce the extra milk:
These cows will be grazing late in the afternoon while other, lower-performing cows will be lying down (observe this yourself);
Unfortunately, for the high-yielding cows who are grazing late in the afternoon, grass cover is very low. Consequently, bite size is small and, therefore, intake is reduced by 1-2kgDM, and the DMD will be 1-2 per cent lower due to stem. Therefore, these cows will lose weight;
Therefore, cows should be given blocks of grass that last for 24, 36 or 48 hours;
As well as being beneficial for the cows, it will be less laborious for the farmer.
Animal health – preventative care
Farmers have become careless on preventative healthcare of animals. Preventative care is cheap, very effective, and reduces both labour and expensive veterinary bills. You should use your vet for this purpose but the following reminders may help:
Treat calves for blackleg;
Stomach worms will not be a problem until late June/July;
If using yellow/white dose, no treatment is necessary until then. I favour this procedure because it builds up some animal immunity and won't lead to drug resistance;
With the ivermectin-type products and boluses, treatment begins now as per the recommendations of the manufacturers.
Hoose is a different 'kettle of fish'
Mild weather in May can lead to an attack;
Strong calves will cough first;
When the first calf coughs, dose all calves with the cheap dose and this will cure the problem and convey immunity to all calves.
Young cows (first calvers) that have low immunity may need a worm dose:
Talk to your vet for the product that has a 'no-milk-withholding period';
To save dosing costs, work on the principle of building up the animals' immunity from the calf stage;
Magnesium (Mg) is a must for cows – make sure they are getting at least 2oz per cow per day.
Lameness in cows must be controlled at first sight
Lameness will seriously reduce milk yield and fertility at this time of year;
Use the FRS hoof-care service;
Foot-bathing with copper sulphate (4kg in 100 gallons water) on three consecutive days every month may be necessary;
Check your roadways but, particularly, the concrete yard section where small stones can do very serious bruising damage (they must be brushed off daily);
Avoid too much movement in the collecting yard as it causes lameness.

Your cows should not be exposed to injections, testing, freeze branding, stray electricity or hassle, etc., during the breeding season:
Fertility will disimprove.

Iodine (I), copper (Cu) and cobalt (Co) are important minerals during the breeding season:
Iodine at 1.2cc per cow per day in water (do not forget bulling heifers);
Cu, in a bolus or meal, are your options now;
Cu is only a problem on some farms.
Mastitis prevention in May
Ensure the milking machine is working correctly – when did you last test it? Change liners at 2,000 milkings (for many farmers, that means now);
Milking routine – unfortunately, many farmers are causing mastitis by having bad milking routines. Learn through your discussion group;
No teat dip, or inadequately done. As it reduces the spread of mastitis by 50 per cent, it must by done and done correctly, with each cow getting 15-20cc (even over four teats) each milking;
Take out seriously infected cows (know by milking recording) as they infect other cows. This is a waste of money (€1,000 + per cow culled) if you don't address the basic problem causing the trouble;
Stray electricity can be a problem on some farms and you should have it checked by an electrician;
Where somatic cell count (SCC) levels are high, a pre-milking disinfectant spray is recommended;
Large herds with mastitis problems should draft out mastitic cows, slow milkers and milk them separately in the last row. This means no cross infection and they won't slow up milking.
Bits and pieces
If you need to know your milk yield for this year, multiply your May peak per cow per day by 220. For example, if a cow peaks at 25l/day in May, then her expected yield per year will be 5,500l.
Or, if you sell 2kg milk solids (MS) per cow per day, multiply by 250 and you will know you will sell 500kg MS per cow this year. This is such an important exercise as you will be able to tell your bank how much milk you will produce this year.
Cut first cut silage in two lots:
Fields closed six to eight weeks should be cut end at the end of May;
Late closed (light covers) fields should be cut mid-June;
This procedure should ensure an even arrival of after-grass and less chance of shortages in July.

The following 'labour-saving' suggestions may help to make your life easier:
Spread once every four to six weeks, depending on your stocking rate, instead of after each grazing;
Milk every 16:8 or near it, instead of 12:12 milking intervals, as there is no loss of milk, and this enables you finish at 6-6.30pm;
Give cows/cattle 36 or 48-hour grazing paddocks, and grass budget to reduce topping and workload;
If really working long hours and always 'coming from behind', then you should use contractors for fertiliser spreading, spreading slurry, cutting silage, fencing, and milking cows occasionally (FRS);
Use a teaser bull to identify bulling cows from late May on and use a suitable stock bull to 'mop' up;
Postpone weaning late calves off milk substitute until calf is at least 110kg.