Supplementary Feeds

Hello :) In this post we'll be discussing the pros and cons of many of the energy and protein supplements that can be added to an animal's feed ration. This may be a bit of a dry post, but hopefully it will be useful when it is time to revise for exams. I've listed the major advantages and disadvantages of each of the feed types. 

Energy Concentrates

Energy concentrates are feedstuffs added to a ration with the aim of increasing energy density. Examples of energy concentrates are cereal grains and co-products, molasses, fats and oil. Energy concentrates:

• Have a high concentration of digestible or metabolisable energy
• Crude protein is usually the most variable component
• Are highly digestible
• Most cereal products are deficient in calcium but are adequate in phosphorus
• Cereals are generally deficient in beta-carotene and vitamin D

 Wheat

Pros:

• High energy grain

Cons:

• Very low in calcium. 
• High in starch and low in fibre (risk of acidosis) 

Barley

Pros:

• Medium energy feed
• Grown widely through out Australia

Cons:

• Deficient in lysine
• Low starch digestibility: this may lead to excessive hind gut fermentation in horses which causes laminitis, diarrhoea, and nervous behaviour. Processing is required to prevent this. 

 Oats

Pros:

• fibrous outer hull reduces risk of spoilage by mould and insects during storage
• High fibre content: this reduces the risk of rumen acidosis making it a safer grain for horses and ruminants
• Horse digest the starch well in their small intestines. 
• When fed to horse, they don't require processing

Cons:

• Low energy concentration = more bulk to be fed (this may be a problem for animals with a poor appetite)
• Crude protein and fibre content is variable 

Triticale

Pros:

• A hardy crop
• energy dense
• more crude protein and better amino acid profile than other cereal grains
• palatable

Cons:

• must be processed (it has antinutritive components which are destroyed by heat)
• are susceptible to mould.

 Maize

Pros:

• Energy dense (more than oats and barley) 

 Cons:

• prone to moulds and mycotoxins
• very low in lysine, methionine and tryptophan

 Sorghum

Pros:

• A hardy plant which is able to withstand heat and drought better than many grain crops.
• less susceptible to some insect pests
• energy dense 

 Cons: 

• processing is required to increase palatability.  

By-Products and Co-Products

Bran and Pollard

Bran refers to the coarse, fibrous outer coatings of wheat kernels. The pollard contains the fine midlings of the wheat which includes the endosperm and so is higher in energy, protein and fat when compared to bran.

Pros:

• highly palatable
• high in protein and phosphorus
• bran is a useful source of B-vitamins

 Cons:

• the protein is not of good quality
• Pollard is dusty and when fed dry may lead to respiratory problems
• most of the phosphorus is present as phytate which may reduce the availability of calcium, zinc and iron. 

 Rice Bran and Pollard

Pros:

• High fat content
• more palatable
• less dusty

Cons:

• More prone to rancidity during storage. 

Brewer's Grains

Pros:

• A good protein and energy source 
• Less degradable in the rumen and so makes a good source of by-pass protein. 

Cons:

• Not as palatable as the original grains
• Wet Brewer's grains spoil quickly 
• High fibre so their use is limited in young pigs and poultry 

Malt Culms 

Pros:

• High in protein
• High in fibre, thus a safe protein supplement for ruminants
• Palatable for livestock

Molasses

Pros:

• Good energy source
• Very palatable
• Very high in Potassium
• Useful for reducing dust in rations
• It's sticky so it can be used to deliver medications

Cons:

• Must be introduced to the diet slowly as there is a risk of rumen acidosis.
• Low in protein

 Other by-products which can be used to supplement the diet include:

• Citrus pulp
• Apple pomace
• Tomato pomace
• Grape pomace
• Bakery waste
• Confectionery waste
• Sugar beet pulp
• Lupin and soybean hulls

 Protein Supplements

A protein supplement is a feed that contains more than 20% crude protein on a dry matter basis. They are added to rations to increase the quality and quantity of the protein given to the animal. There are two broad categories of protein supplements: those that come from plants and those that come from animals.

Those of plant origins have between 30-50% crude protein and are usually the removal of most of the oil from the plant. These supplements are usually low in Calcium, Vitamin E and Beta-carotene but are a good source of B-vitamins. These are often used in conjunction with supplements from animal or marine origin.

The protein supplements that come from animals contain between 50-90% crude protein. They often have high quantities of minerals and B-vitamins but are less palatable than the plant-derived protein supplements.

Soya Bean Meal

Pros:

• contains 40-50% protein
• high in energy
• highly palatable to livestock
• Has an excellent mix of essential and non-essential amino acids
• has a significant proportion of undegradeable intake protein. 

Cons:

• Must be carefully stored to prevent rancidity
• Expensive
• Has anti-nutritional factors which must be removed with heat treatment (although this isn't required for ruminants).

Canola Meal

Pros:

• palatable
• 33-35% protein
• good source of lysine

 Cons:

• For monogastrics, canola meal contains substances that may interfere with thyroid hormone function.  

Meat and Bone Meal

Pros:

• Cheap

 Cons:

• Is a Restricted Animal Material and so it can't legally be fed to ruminants in many places. 
•  High ash content
• High levels of Calcium may affect the absorption of copper and zinc in the small intestine.  

Blood Meal

  Pros:

• High protein content (80-95%) 
• Very high lysine, arginine, methionine and leucine levels. 

 Cons:

• A restricted animal material - it can't be legally fed to ruminants in many places. 
• poor palatability
• low protein quality - their is a poor balance between essential and non-essential amino acids. 
• Most of the protein is resistant to rumen degradation.   

 Fish Meal

Pros: 

• Very high crude protein
• very high lysine

 Cons:

• A restricted animal material and so cannot legally be given to ruminants in many countries. 
• If too much fish meal is included in feed rations for pigs, the pork may retain a fishy taint.  

 Linseed Meal

Pros:

• Has high amounts of omega-3
• Protein content = 30-38% DM
• Very palatable
• May be fed to horses to relieve constipation.
• Has a reputation for enhancing coat appearance. 

Cons:

• Contains an enzyme that can release toxic cyanide gas from compounds in the seed when exposed to cold water. It needs to be heat treated to destroy the enzyme and prevent this from happening. 
• Toxic for poultry
• Very deficient in lysine and tryptophan
• Generally more expensive than canola and soybean meal.  

 Lupins

Pros:

• Excellent source of energy and protein for pig and ruminant rations. 
• Low starch content minimises risk of lactic acidosis. 
• High digestibility
• Resistant to weevil attack

Cons:

• May contain anti nutritional and so may require processing.

Sunflower Seeds and Meal

Pros:

• Contains some linoleic acid
• Palatable and well accepted
• Good source of protein

 Cons:

• Because of the high oil content, sunflower seeds and meal may be prone to rancidity if stored in warm conditions. 
• Deficient in lysine - this limits its use in monogastrics.  

 Peanut Meal
 
Pros:

• palatable and well accepted
• high protein content (47% CP)

Cons:

• Prone to rancidity
• Can be contaminated with a mould that produce dangerous alfatoxins. These alfatoxins can cause severe liver damage. 

Sorry for the dry post - hopefully it will be useful for revision when it comes to exams :)