Ken Gill November/December Update
Breeding season in full swing
- Set start and end dates for your breeding season to tighten calving spread
- Ken operates a 6 week breeding season
- Heat detection is vitally important in a 100% AI system
- Dose cattle based on FEC samples this winter
- Is there enough ventilation in your cattle sheds?
- Lying and feeding space for cattle in sheds is very important for meeting performance targets during the housing period
Testing silage is saving money
- Take silage samples on your farm (cost ~€32)
- Balance diets for energy and crude protein
- A mineral analysis costs around €90 and can be useful to detect mineral deficiencies on your farm
Ken’s breeding season started on 2nd November and is going well. There have been 30 cows and 8 heifers bred as of 10th November, out of 63 cows and 18 heifers. Ken plans to stick with a 6 week breeding season and will be finishing on 14th December.
A combination of AI bulls are being used for replacement and terminal traits, and they have been matched to each cow and heifer (see September/October update). The shortest gestation bulls will be used on the latest bred cows and heifers to keep the calving spread tight for 2023.
The cows are housed and Ken is visually heat detecting 3 to 4 times per day.
FEC samples were taken for the suckler cows and they were clear for liver fluke, rumen fluke, tape worms, lungworms, stomach worms and coccidia. As a result of this they won’t be dosed at housing.
Another FEC sample will be taken from the yearlings when they are finished grazing the catch crop.
The ventilation calculations were completed for both of Ken’s sheds. Clean air is particularly important from a disease risk perspective over winter as it moves through the shed to remove gasses, odours, dust and bacteria. It should also remove the moisture and heat generated by the animals. To be effective it needs to work on calm days. Fresh air is actually a disinfectant; if a virus is coughed up in a building, it will last for 20 hours. However, if the same virus is coughed up outside in fresh air, it will last for about 20 minutes. Air actually deactivates the virus, so we need to make the maximum use of fresh air in sheds. The ‘stack effect’ is a ventilation method and is driven by the heat produced by the animals and by the roof slope. The animals produce heat and warm the air. The warm air rises following the slope of the roof, escaping through the outlet (highest point of the house) and is replaced by clean fresh air via the inlet.
The ventilation inlets and outlets were calculated for both sheds on the farm, which is computed based on the average animal weight, the number of animals to be housed, the total shed floor area and two charts (to get the ventilation outlet area and the height factor). The air inlets should be at least double the air outlets.
Both sheds had more than enough air inlets through a combination of open air space above the walls and openings by feed passages. The outlets are also effective and consist of openings at the top of the cows shed and raised sheeting in the yearling shed.
Lying and feeding space are other important considerations for cattle over winter. Work in Teagasc, Grange and across the world has shown a 20kg difference in carcass weight of 650 – 700kg for steers housed from 2 – 3m2. As Ken is organically certified, the lying space requirements are higher for his cattle than conventional cattle. Organic calves require 3m2 of lying space (versus 1.7m2 non-organic), cows require 6m2 on straw (3m2 non-organic) and Ken’s yearlings need 4.5m2 (3m2 non-organic). By calculating the lying area available to the cattle in each shed, it can be divided the space requirements for each category to indicate how many cattle should be housed there. Both of Ken’s sheds have more than enough lying space for all his cattle to meet the organic standard.
The feeding space was also calculated for the different sheds and shows that an extra 23.4m of feed space is required in the cow shed (cows require 0.5m/head on ad lib silage). This can be simply sorted by feeding on both sides of the feed passage and adding a round feeder or providing access to an existing feed barrier in the shed. The yearlings require approximately 0.4m/head feeding space and the calculations show that an extra 5.2m of feed space is needed, which again could be simply sorted by adding a round feeder or adding another feed barrier area to the shed.
Ken has taken silage samples from the farm and will balance winter diets based on the results. Two sample taken to date show excellent results. The red clover silage was 77.56% DMD (dry matter digestibility) silage at 14.8% crude protein and baled grass silage is 75% DMD at 14.1% crude protein.
As Ken’s autumn calved suckler cows have the highest energy demand they can be fed the 77.56% DMD silage and the yearlings can get the 75% DMD silage when they are housed. As the silage DMD % is so high, organic oats or ration is not required to balance the diets which is a huge saving cost to Ken this winter. The yearlings are currently grazing the catch crop mix. No mineral supplementation has been given to them, ideally they should be given a bolus or mineral lick that provides iodine, selenium, copper and cobalt.
A further standard and mineral silage sample has been taken from the silage pit and Ken will take a further two samples from the pea/wheat combi crop and from second cut red clover.