Animal Health and Soil
Having worked as a Veterinarian in Rural practise for over 30 years in New Zealand I have observed the decline in animal health and reproductive performance in particular and the associated increases in costs to the farmer. I have mainly been involved with Dairy farms, but also sheep, beef and deer farming. The first 19 years in the Taranaki Wanganui districts and since 2001 Canterbury.
Over the last ten years I have researched why these problems have evolved and have come to the conclusion it is due to the decline in the quality of the animals feed intake in terms of total mineral content availability and the imbalance of the protein to carbohydrate ratio in their diet. I also realised this is directly related to the poor soil health where these feed inputs are being produced from.
All plants require electricity to grow. Hydroponic farmers all know about this and if the level of Electrical Conductivity of the water their crop is growing in is either too high or too low their crops fail in both yield and quality. Hydroponic growers add various salt compounds to water to create this electricity and also to provide the nutrients the plants need to grow. Plants growing in soil are no different.
In a good healthy soil the Electrical Conductivity increases naturally as the soil temperatures increase following winter. This is because the soil microbes, the bacteria in particular, begin to reproduce faster. These bacteria don’t live long and when they die they split open and release various salts into the soil solution which create a spark, electricity. The “skins” of these dead bacteria are then eaten by the larger protozoa and because the Carbon to Nitrogen ratio of the protozoa is 30-1 and the C-N ratio of the Bacteria is 5-1 the protozoa are consuming excess Nitrogen for their requirements and so they excrete Ammonium Nitrate as a waste product. Nematodes also consume bacteria and their C-N ratio is 100-1 and so they also excrete Ammonium Nitrate. Ammonium Nitrate doesn’t leach from soils, attaches to the organic matter in the soil and just happens to be the best form of Nitrogen for plant vegetative growth. The soil microbiology involved in these processes and their larger cousins’ worms, nematodes etc all breath Oxygen just like us and breath out Carbon Dioxide (CO2), again just like us. They can’t exist in compacted soil where oxygen levels are very low. Soil Compaction, alongside Soil PH, are the two most important and limiting factors on our farms today. They are the root cause of our problems.
Plants make sugar from Carbon Dioxide (CO2) and Water (H2O). This process is called Photosynthesis. Sugar in its simplest form is made up of 6 Carbon elements,12 Hydrogen and 6 Oxygen. (C6H12O6). Complex sugars are just long chains of these simple sugars with various other elements joining them all together.
It is extremely important that farmers understand how Photosynthesis works. Plants take in CO2 and H2O and produce Sugar and Oxygen. Life forms other than plants then take in the Sugar and Oxygen and give off CO2 back into the air. This is part of the Carbon Cycle of life on earth.
Simply put, Photosynthesis happens in two stages, the light and dark reactions of photosynthesis. Photosynthesis is dependent upon the functioning of both reactions. In the first stage of photosynthesis, the light reaction breaks apart water and produces the energy needed to drive the second stage. The second stage of Photosynthesis is where the CO2 is smashed up. This stage, “the dark reactions” use the energy produced in the first stage to join the loose C, O and H elements into sugar. Without the first stage of Photosynthesis happening sugar cannot be produced irrespective of how much sunshine the plants are exposed to.
The energy created in the first stage is stored in the molecule, ATP (Adenosine Triphosphate). The ATP molecule is critical to a plant’s health and the energy currency in ALL biological organisms. Producing ATP during this first stage requires sunlight, minerals and water. One mineral in particular is vital to producing the ATP molecule. Available Calcium is vital as a co-factor in smashing up water (H2O) and producing ATP. Without available Calcium, photosynthesis will not function and plants energy (ATP) will be low. The “P” in the ATP is Phosphorus.( Calcium and Phosphorus in an available form in our soil is so critical). If you haven’t got both you can’t get the ATP produced. No ATP, No Photosynthesis, No Energy, No Sugar, No plant health.
In order to produce energy in the plant, you need available Calcium and Phosphorus in the soil. The availability of Calcium and Phosphorous in the soil requires energy as well. Monitoring and maintaining the energy in the soil with the proper minerals and biological organisms will give your plants the base they need to function properly. This is what the soil Electrical Conductivity provides.
I like to use the analogy of a high-rise building with a lift carrying people up to the various floors. The people in the lift are Calcium and Phosphorus and both have to be present. But Phosphorus also piggy backs all the other cation elements when it goes up the lift so that the lift is also full of numerous other elements needed for a healthy plant to grow and reproduce, but only if Calcium and Phosphorus are present as well.
But for a lift to work it needs power, electricity. The available minerals in the soil, therefore, are essential to production of energy. An absence of available calcium and phosphorus in the soil, inhibits plant physiology “lifts”. So for a plant to function at its photosynthetic maximum, we need available Calcium, Phosphorus and Soil Electrical Conductivity.
The most common cause of soil and plant health problems, comes from a lack of available Calcium, Phosphorus and/or soil Electrical Conductivity. If your soils are compacted or their aerobic (oxygen containing) zone depth is shallow there isn’t much microbiology living there and so not much Electrical Conductivity(EC) can be produced. But with the conventional fertilisers most farms currently use this isn’t a problem because salts can be applied and they will create soil EC. All fertilisers are salts of one kind or another and when they are applied to soil and there is moisture present they will create spark and electricity.
However, there is a problem. Many of these fertiliser salts, urea for example, will cause the structure of the soil to alter over time so that the soil colloids don’t associate with each other in the way they are supposed to. The soil colloids are basically plates, like dinner plates. They should have a strong negative charge on their outside edge and have a positive charge on their flat surface. If this is so they stick to each other +ve to -ve so that the edge of one colloid will be standing up on the flat of another and that one’s edge attached to the flat of several others basically building a card house out of a pack of cards.
There is air between the cards where the feeder roots of the plants grow into, the air breathing bacteria and fungi live in on and around the plant roots producing humic and fulvic acids, humates, digesting old dead plant material, being fed sugar by the plant roots, pulling elements attached to the soil colloids off and into the water solution in amongst the plant roots making them available to the plants. This is also where water can attach to organic material in this aerobic zone, humates, and provide a store of water for plants during dry periods.
So, if we have little aerobic zone and we want a crop to grow we put down salt fertilisers, it makes a spark, the plant grows, but is it healthy? No, it’s not. This is why……………...
Let’s use Urea as an example. When urea (CH4N20-) is applied and moisture is present it activates and creates soil EC. In the plant a number of things then happen. The plant will take in the nitrate nitrogen via the roots. Within a plant roots resides an enzyme which will convert the nitrate into a protein. The nitrate reductase enzyme’s job is to convert nitrate into a plant protein. This enzyme function is highly energy demanding. When flooded with synthetic nitrate nitrogen this enzyme goes into overdrive making proteins. For the plant, this causes a massive drain in energy reserves which are now diverted into the roots for the conversion of nitrate into protein. The more synthetic nitrogen that is applied the more sugar (energy) is needed to metabolize it.
So, after a big application of Urea, the plant has taken a bit of a hit to its sugar levels. In order to make up the demand in sugar, the plant will need to increase chlorophyll production. Therefore, a plant produces more sugar making factories or leaves/chlorophyll. This is an effort to make up for the loss in energy reserves or sugar. We view this as growth or a dark green colour. To many this is seen as a positive improvement, however if available Calcium and Phosphorus are NOT present this new growth will not function properly.
In the absence of available Calcium and Phosphorus, the “lift” will fill up with Potassium(K). Potassium is an electrolyte mineral. When a plant’s energy levels are NOT being met with Calcium and Phosphorus, the plant will fill the energy demand with Potassium. Potassium, as a mineral, has a large hydrated radius or it holds on to a lot of water. When the plant takes up a lot of Potassium in order to fill the energy void, the plants soluble sugars further dilute. Now the plant is very vulnerable to diseases and insect attack as neither can consume high levels of complex sugars. Without the proper Calcium and Phosphorus, which builds cell wall strength, the over hydrated cells burst. The ruptured cells degrade crop quality and create an environment on the leaf or fruit surface open to pests and diseases. These low-quality crops not only increase pest management costs, but also can be life threating to stock if used as a forage or feed.
When we are feeding our animals low sugar, low mineralised feed, with a high water content and relatively high protein content we are in fact feeding an imbalanced diet to the rumen microbiology. Our ruminant farmed animals consume plant material but they in themselves don’t live on this plant material. The microbes in the rumen do and the cow or sheep lives on the dead microbes that wash further down the gut.
What happens in the rumen when feed low in sugar, high in protein and lacking fibre as well, is the start of the animal health issues we see.
Regarding fibre, the rumen is a bag with strong muscles in its wall designed to create waves around the bag to stir up the contents. But it needs some solid material in amongst the fluid in the bag to create agitation. If there is little fibre in the rumen the mixing doesn’t work well just as your clothes don’t get washed properly if you take the agitator out of your clothes washing machine.
Rumen microbiological flora are similar to those in the soil in that they need a carbohydrate, sugar, source for energy to live and a protein source to consume to build their bodies from. When the protein to carbohydrate ratio is out of balance the rumen biology will turn some of the excess protein into energy to compensate. This is not only inefficient use of protein but it produces ammonia gas within the rumen which causes a PH change in the rumen. This is called sub clinical rumen acidosis. This causes a burning effect to the rumen wall allowing some bacteria to enter the blood stream. When this happens some of these bacteria can become trapped in the smallest blood vessel as they are carried around the body and the most common symptom can be acute, sudden and severe, lameness. This is where these bacteria block the little arteries’ in the toes causing a build-up of pressure and vessels to burst. Like hitting your thumb with a hammer. After a few days the animals stop being sore and seem to recover. But the blood clot damage is still there and when it grows down the horn to ground level that powdery blood falls out leaving a gap where mud and infection can enter and a second more-long lasting lameness event may occur months after the original insult. At the same time the bacteria cause the blood clots in the feet, bacteria can also become trapped in the tiny vessels in the liver, some grow and develop into Liver Abscesses which can further develop into more serious consequences for the animal later on. This is often reflected in a high incidence of peritonitis reported in cull animals sent to slaughter facilities.
The Ammonia gas in the rumen also gets into the blood stream but can’t be directly excreted and first has to enter the liver where it is turned into Urea. The Urea is then returned to the blood stream and can be excreted via the urine. In dairy cows the urea can also be measured being excreted via the milk and referred to as MUN (Milk Urea Nitrogen).
The conversion of the Ammonia Gas into Urea causes a lot of work for the liver and uses up energy that the animal could have otherwise have used elsewhere. But the worst consequence can be due to the change of blood PH that occurs when you have all this excess of Ammonia Gas and Urea circulating before it can be excreted. It is the Embryonic Death that can occur as a result of fluctuating blood PH. Unfortunately, in New Zealand seasonal dairying where most of the cows calve in spring the mating period corresponds with grass growth really starting to fly under ideal growing conditions of moisture and warm soil temperatures. These pastures tend to be higher in protein and lower in carbohydrate. If you compound this with more artificial nitrogen fertiliser use the protein carbohydrate imbalance is made worse.
I have been involved and helped pioneer the early diagnosis of pregnancies at 5 weeks post mating to look to identified failed pregnancies early enough to intervene to help create a pregnancy. During the course of thousands of cows tested over many years being confirmed pregnant I observed large numbers of cows subsequently being diagnosed empty some months later when I knew they had been pregnant earlier. I also observed at the time of the early test that a number of cows had dead embryos still palpable. Over some years of observation, I was able to relate this phenomenon to when I also observed the cows to be very loose in their faeces and I came to relate this to the subclinical rumen acidosis they were currently suffering. Milk production was also seen to suffer. In New Zealand some experts say this doesn’t happen in New Zealand and it is a phenomime only seen overseas and that our cows are different and high MUN levels are not bad, encouraged even. They are in my experience completely wrong.
I believe the majority of the Animal Health and Production failures we observe are directly related to the unhealthy state of the soil on many of our farms as well as the inappropriate use of some supplementary feeds and the over use of manufactured nitrogen fertiliser.
It doesn’t have to be this way and by applying the scientific knowledge of how soil should be working and using only products that improve soil health we can produce better quality feed that is a balanced diet for the rumen microbes that feed our grazing animals.