Apr 16, 20216 min read

TRAC Beef & Sheep Newsletter - Autumn 2021 Edition

Traveling through Autumn, we have seen the full cycle of weather, ranging from wet to warm and then to windy days which has made for some fun events as we have had the opportunity to travel around and spend time with grower groups and field days. Some key discussions we have been having are around vitamin relationships to disease, calcium regulation, and milk production in ewes as we prepare and navigate our way through lambing.

The team at TRAC has been having a lot of fun on the road so check out our new Facebook page after reading through the articles we have put together on prominent areas of interest at this time. If you have any further questions our team are available and more than happy to help.

Calcium Requirements for Pre-Lambing Ewes

Calcium is one of the most important minerals in an animal's body. It is a critical regulator of multiple physiological processes, including blood coagulation, nerve conduction, membrane permeability, muscle contraction, enzyme activity, and hormone release. Calcium is stored mostly in the animal bones with a little stored in the tissue and blood.

Animals that are bred for increased milk production like dairy cows and multiple bearing ewes will use more calcium in their colostrum and milk production than a human. In some cases, more than 4x the calcium per litre of production. Adding to that the fetus does its most explosive growth in the last trimester of the pregnancy right before the mother has their huge demand for calcium for lactation.

We now understand that if we feed the ewe/cow a diet high in magnesium before calving that we can help her to mobilise some of that calcium from her bone storage and have that ready in her blood for milk production. This approach has been successfully used in dairy farming for many years.

But can we keep going to the bone “bank” every year hoping to mobilise more calcium to help the ewe/cow dodge hypocalcaemia or milk fever?

What happens when the “bank” is empty? Then the ewe/cow is more likely to not have enough calcium stored to get through milk production and will most likely fall in a hole at giving birth or around that stage.

If we start topping up the bone “bank” before the animal starts to need her reserves, then we have a better chance of a seamless transition into lactation. Animals that give birth in the Autumn spend a lot of time over summer on supplementary feed, which is inherently low in calcium levels. Also, spring lambing/calving females spend the last part of gestation in winter where grass growth can be slow and is often pushed along with urea, which has been shown to lower the calcium level in the grass.So how do we get a highly available easy to feed source of calcium that is going to help top up the bone “bank” for our animals? Look no further than the TPM Bovine & Flock Boost range of loose lick minerals.

With a highly concentrated source of minerals, your animals will be able to refill their bone “bank”, so it is ready to help your ewe/cow for their next lactation.

ENERGY BALANCE FOR LAMBING & LACTATION

Chasing milk production in sheep generally isn’t the primary focus unless you run a sheep dairy. However, it definitely needs to be further up the focus list when preparing and managing lambing ewes.

See below a graph on ewe energy requirements we shared last year, once the ewes begin lactating their energy significantly increases. This extra energy is then efficiently converted to milk for lambs when their requirements are met.

A key thing to note in the graph, the grey bar shows energy provided from 48% NDF and 9.8 ME cereal or pasture hay which was typical from the 2019 harvest. Now in 2021, and mostly using 2020 forage as our base, the situation is extremely different.

In 2020, across many regions were less than ideal baling conditions with consistent rains that either kept hay on the ground too long; or cut very late; or both. This resulted in feeds with very low protein, down to 5% CP and very high NDF, up to 60%. These results are very similar to straw, which we know can’t sustain animals and definitely can’t provide enough energy to successfully lamb and continue to produce good quality milk.

Where to start

Quickly grab a forage sample and send it off to Forage Lab Australia (FLA) for an A1 NIR analysis, they have a quick turnaround and comprehensive results. FLA will provide Crude protein, but also critical information on ADF, Lignin, sugars, energy and more.
Match grain to the hay – a good mix may consist of both lupins and a cereal grain, such as wheat or barley which provide energy density and valuable nutrients.
- Lupins will provide much-needed protein to get around our target of 14-16% CP
- Cereal grains will provide starch, a highly valuable component of milk production for volume and milk protein. Starch is a precursor for glucose, which also provides benefit to the foetus and ewe pre-lambing. Consider wheat or barley.
Begin feeding grain 3 weeks prior to lambing and always introduce slowly – ruminants are habitual animals and benefit from consistency in routine. Trail feeding will allow controlled grain intake, or ad-lib feeders can be useful when labour is not available. If using an ad-lib feeder, it is critical they never run out of grain or animals will become stressed and likely overeat when it is refilled. Always have forage available ad-lib and clean water.

Meeting energy requirements will reduce risks of preg toxaemia; low glucose, and support milk production for lambs to also have better survival rates. For best results, systems must be adapted to feed quality available, using the same recipe as last year may not yield the same results.

STAR-GAZING STOCK Are your SHEEP Polio AFFECTED?

This year we are hearing more farmers ask the question “Why are my sheep acting like they are blind and staring off into the distance?”. While we can’t be 100% sure without seeing the animals, there is a possibility that it could be ‘polioencephalomalacia’ or PEM, which is a result of the body not producing or absorbing enough Thiamine or B1 Vitamin.

Both cattle and sheep can be affected with younger animals more prone to the deficiency due to the limited function of their rumen. Clinical signs of this illness are disorientation, wandering, blindness, and/or star-gazing.

While PEM can occur in different scenarios it usually occurs in conjunction with low Thiamine levels in the animal. Some of the factors that seem to be present in many occurrences of this issue are:

high grain feeding diet,
high sulphur content in the drinking water, and
animals that are consuming a large number of summer weeds that minimize the function of the liver.

Blind and star-gazing animals have only recently (last 3-4 years) appeared to be an issue, and as most normal functioning adult ruminant can produce enough Thiamine in the rumen it begs the question what has changed?

Whilst we don’t have a definitive answer there are a couple of schools of thought:

Now that, as farmers, we have recognized the importance of getting our ewes in better body condition score before joining and lambing, we see more grain being feed to animals. From what we know about rumen bugs, the ones that digest grain don’t produce large amounts of thiamine from that diet.
Some summer weeds can produce a counteractive product called thiaminase which is sometimes 100 times stronger than thiamine. As we have had plenty of summer rain in the last few years more weeds have been able to grow.

While this is not conclusive, we do know that we can supply Thiamine for your stock via the TPM Bovine & Flock Boost loose lick range. We also can customise your product with increased levels of Thiamine, if your stock is presenting deficient.

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