Veterinary Handbook Disease Finder

Veterinary Handbook Contents

5.5 Feed Quality Problems

5.5.1 What Are The Feed Quality Problems?

Feed quality problems often involve physical integrity and nutritional composition of the feed. They include provision of improperly formulated pellets, provision of nutritionally unsuitable hay and chaff, and spoiling of feeds. Consequences may include feed refusal, indigestion, and creation of unpleasant pen conditions if ammonia or moisture levels increase.

5.5.2 Situations Leading To Feed Quality Problems

Situations where feed quality problems may arise include:
  • Pellets, hay and chaff that are wet, mouldy, dusty or decayed.
  • Contamination of feedstuffs either in storage or in troughs with fuel, chemicals, sawdust, saliva, urine, faeces, or sea spray.
  • Sawdust used for bedding may be spilt in feed troughs during spreading. It is indigestible and may cause obstruction and even toxicity depending on the type of wood or whether the sawdust is contaminated with chemicals.
  • Hay and chaff made from straw may be indigestible. In some cases, legume chaff/hay may contain sufficient levels of nitrogen that increase the risk of dietary diarrhoea and contribute to elevated ammonia levels.
  • Fodder fines or dusty feeds may be associated with increased risk of bloat, respiratory and eye problems. Fodder fines may occur due to the manufacture of pellets if the series of heating, pressurising and steam conditioning processes has not been optimal. Dust levels in pelleted feed may be exacerbated when bags of pellets are repeatedly relocated by hand or loose pellets are repeatedly augured between silos.

5.5.3 Detection Of Feed Quality Problems

Many feed quality problems may be detected by inspection of the feed which should be done routinely. Observation of animals is also very useful in detecting feed problems and may raise suspicions about formulation as well as other attributes of quality. These observations may include:
  • High ammonia concentrations in pens may be from excess protein or urea.
  • Acidosis and laminitis may be from excess starch (cereal grains in pellets may vary greatly in quality, some having high starch levels).
  • Rumen bloat and irritation of the respiratory tract and eyes may be from excessive dust/fodder fines.
  • Heat stress may be exacerbated if animals are ingesting insufficient salt in feed.
  • Wet pen conditions and high ammonia levels in pens may be from excessive salt causing increased urination.
  • Inappetence may be from excess salt, urea, urinary acidifiers, rumen modifiers or mould in the feed.
  • Low weight gains may be from insufficient protein.
  • Abomasal ulceration and rumen bloat may be from insufficient long length fibre.
  • Premature lactation in female cattle may be more likely in animals being fed mouldy pellets.
Untouched feed or diarrhoea may be the first sign of problems with feed quality and should trigger a close physical examination of the feed for abnormalities.

5.5.4 Interventions And Prevention Of Feed Quality Problems

  • Feed storage should provide protection from rain, sea spray, deck water and bilge overflow. Store bagged feed off the floor and consider covering with tarpaulins. Tarpaulins should not be weighed down with bags of feed. They may become spoiled, and if contingencies eventuate, every last bag of feed may be needed. Poison baits may control rodents. Feed may need storing in secure pens to prevent it being eaten by escapees, especially goats. The ASEL prescribes emptying feed storage tanks at least every 90 days.
  • Suspect feeds (poor quality or partially spoiled) may be withheld, blended with pellets, cereal hays and chaffs, or their use may be postponed as long as possible. 
  • Troughs should be routinely inspected for sawdust, slobber or sea spray affected feed, and faeces, the offending material should be removed. If feed is only slightly affected by slobber or sea spray, it may be turned over by hand, breaking it up and mixing it with fresher feed rather than being discarded.
  • If problems with pellet formulation are suspected, there should be prompt reporting of accurately observed and recorded signs to the exporter and feed manufacturer. This may allow timely modifications to or recall of other batches.
  • If feed has become spoiled, identify how it happened to inform preventative measures. Hay, chaff and bags of pellets (if used) may have been stored on livestock decks in imperfectly protected locations, including near engine rooms and chemical stores. Pellets held in ship's storage tanks may become mouldy or contaminated with water, rust or chemicals, especially if stored for long periods.