Novel Supplementary Feed Options: Citrus, Onions, Bakery Waste, Seaweed +more (2/3)

All this week on Table Talk we are discussing alternative feed options for ruminants.

In these dry times, grain and hay prices are at soaring highs and stockpiles are becoming exhausted. As there remains a continued need to feed stock on hand, we thought it might be worthwhile to investigate if there are other opportunities out there for producers to consider.

In our first post, we outlined alternative feed options for producers. Catch up here. Today, we will focus on more novel feed opportunities, and our final post for the week will concentrate on what we all need to be aware of when sourcing and using alternative feeds.

The table below outlines some novel feedstuffs, some of which we introduced in our previous post. In this post, we focus on just some of the new and novel alternative feed options that are being used in livestock systems, including citrus byproducts, bakery waste, seaweed, microalgae, and confectionery.

Department of Primary Industries and Regional Development WA

Citrus byproducts

Citrus byproducts include citrus meal, skin or pulp. Pulp is classified as a concentrate but also has value as a partial roughage replacement because of high digestible fibre levels. State Government of Victoria outlines some key points about citrus pulp:

  • It commonly contains about 15 per cent crude fibre in the dry matter.
  • Its energy value is about 94% the value of barley grain.
  • It has only about 7% crude protein in the dry matter.
  • High in calcium and low in phosphorous
  • Usually fed dehydrated.
  • It must be introduced gradually into a ration to let stock get accustomed to its distinctive smell and taste.
  • Levels up to 15-20% are acceptable in feedlot rations.
  • Citrus pulps can also be fed fresh or as silage.

A researcher from Pennsylvania State University reports:

“pulp can be an excellent feed source and has been successfully fed to growing cattle at up to 50 to 60% of the diet. However, additional protein sources will need to be considered when feeding such great amounts to growing cattle and citrus pulp contains only 5 to 8% CP (DMB).”

Onions & Potatoes

Onions are readily eaten by sheep and cattle and have been fed successfully. High in moisture (90%), onions are 9-13% crude protein, 83-90% TDN, 0.35% calccium and 0.4% phosphorous.

When fed at high levels, onions can cause anemia due to the presence of sulfur compounds that cause hemolysis of red blood cells, and off-flavors in milk. To maintain acceptable performance in cattle fed onions, the level of onions in the diet should be limited to 25 percent or less (DM basis) (North Dakota University).

In regards to sheep, State Government of Victoria caution that onions can cause anaemia in sheep so it is recommended to introduce onions over a period of time and only up to 50 per cent of the total ration.

It has been reported that potatoes have a feeding value equal to cereal grain (barley) on a dry-matter basis. They are high in energy and low in protein and vitamin A. North Dakota University outlines:

  • Chopping potatoes will prevent choking in cattle (see sugar beet section for processing ideas), but they can be fed whole if necessary.
  • The choking risk is minimized if they are fed from low troughs.
  • Acclimate cattle to potatoes gradually or they may cause digestive disturbances.
  • Sprouted potatoes contain toxic alkaloids. The long sprouts should be removed before feeding.
  • Frozen potatoes never should be fed because of the danger of choking.

Satisfactory results can be obtained in finishing rations by feeding potatoes free choice with a protein supplement and low-quality dry roughage. Fifty percent of the ration (as-fed basis) as potatoes is probably the maximum for finishing cattle.

Potato waste is an alternative feed option. Learn more here.

Bakery waste

Human food by-products offer an alternative source of feed for animals and large amounts of factory seconds, waste and stale food are discarded from a number of different food industries every day.

Bakery waste, a byproduct of the commercial food industry, can be constantly and readily available due to their perishable nature. Bakery waste includes sliced bread, rolls, croissants, cakes and biscuits and can serve as great sources of energy for ruminant rations.  State Government of Victoria explains:

  • Bakery waste products are usually high in fat and low in crude fibre.
  • Protein levels (on a dry-matter basis) in the range of 10-12 per cent are typical.
  • The low fibre content of the baked material and the baking process itself result in a feed which tends to stimulate ruminal propionate and reduce ruminal acetate production. This is desirable for feedlot livestock being fattened for market.
  • Up to about 10 % can be included in feedlot rations when supplies and economics are favourable.
  • Supplies should be fed quickly.

Research from Western Australia aimed to understand if bakery waste could be successful in a production ration for intensively fed sheep. Bread used was predominately sliced bread and bread roles. The bread was dried and crushed prior to incorporation into the rations. The research found:

  • No significant difference in LWG between treatments
  • Feed intake lower in 50% bread group
  • Feed conversion and wool growth higher in 50% bread group
  • No clinical signs associated with digestive upsets evident
Muresk University

The State Government of Victoria cautions: “Bakery waste however, may potentially contain meat or other animal protein and so should be used with caution and in accordance with ruminant feed ban legislation.”


During a ravaging drought at the beginning of the decade in the United States, corn prices and alternative feed rations were driven sky high. In response, some producers fed cattle candy, gummy bears, marshmallows and even biscuits. One dairy farmer found a good deal on ice cream sprinkles  A Kansas dairy farmer replaced 5% of cattle feed with his chocolate. An article from the US stated:

Cattlemen are feeding virtually anything they can get their hands on that will replace the starchy sugar content traditionally delivered to the animals through corn. . The amazing thing about a ruminant, a cow, you can take those type of ingredients and turn them into food.


Seaweed kelp, the most common type of seaweed available for feeding, contains approximately 30% minerals – compared to 5-6% in hay/pasture. It can be used as a mineral source for livestock and can be fed up to 25% of diet of livestock. It can be quite palatable and the composition is:

  • Dry matter 91%
  • Crude protein 6%
  • Minerals (ash content)%
  • ME value is about 5 MJ per kg DM.


There is growing interest in using microalgae in livestock systems due to its high nutrient value and biomass production. Research from 2015 found that effects of macroalgae on palatability and animal productivity have yet to be illustrated, but it was a good addition to low quality forage feeds. In the research,several species of both green freshwater and marine macroalgae were compared. Findings included:

  • crude protein content ranged from 75.4 – 339.1g/kg DW.
  • four of the six macroalgae species examined had high phosphorous content, ranging from 1.4 – 5g/kg DW
  • marine macroalgae was found to have a higher sulfur concentration than freshwater macroalgae, ranging from 2.9 – 57.5g/kg DW

Another trial conducted three experiments to evaluate the use of microalgae as supplementary feed for beef cattle consuming tropical grasses of low crude protein. the experiments found that microalgae could be used as a protein supplement for beef cattle.


It was reported in the The Omaha World Herald, “A southeast Iowa farmer has come up with a surprising solution to the high cost of cattle feed. Bob Batey, an 85-year-old Mount Pleasant-area farmer, says his 50 cattle devour the sawdust mixture he feeds them. Batey says he stumbled upon the idea in the 1970s, when he noticed that cows were eating the sawdust that had washed into their pasture from a nearby paper mill. Batey, who has a lumber mill on his farm, discovered a way to treat and cook sawdust that results in a digestible feed that cattle find tasty. The sawdust, when mixed with corn, vitamins, minerals and a few other ingredients, has a nutritional value equivalent to grass hay” (BEEF Magazine).


Wastepaper? Really? On some occasions it has been fed as a roughage source, but it is not recommended as “due to its poor feed value and the risk of the paper containing contaminants such as lead, cadmium, polychlorinated biphenyls and other toxic substances”.

State Government of Victoria explains that paper has little or no feed value for sheep or cattle unless it is treated in some way to improve its digestibility and palatability.


This research in China investigated the effects of partial or total replacement of maize on nutrient digestibility, growth performance, blood metabolites, and economics in Limousin crossbred feedlot cattle. The alternative feed sources included brewer’s grains, tofu residue, Chinese jujubes, soybean hulls and molasses. Overall profit ($/head) and daily profit ($/head/d) did not differ significantly between treatments, although the total replacement with alternative feeds showed the highest economic benefits overall.

Do you have mulga on your property? During drought, mulga provides a valuable feed source. Branches and selected trees are commonly lopped or pushed to allow stock access to leaves above browse height. Check out this factsheet to learn more and read producer case studies.

Please complete your own due diligence on any feed introduced into your production system. In tomorrow’s blog we will concentrate on what we all need to be aware of when sourcing and using alternative feeds.