Published by admin on 17 Mar 2009
Ration feedlot
Ration feedlot
Classification of feedlots by feed type.
Dry Lots - 80 to 90 % grain diets
- 1.2 to 1.4 kg/d growth
- feed consumption 10 kg + per day or about 2.7 % of liveweight
Greenlots - cattle fed chopped forage or silage.
- growth rate 0.9 kg/d
Molasses - common in central/south America, some in Qld.
- 55% molasses, 45% hay, 500 g by-pass protein.
- 0.7 to 0.9 kg/d growth.
Feedlotting
• Classified as opportunity (strategic) or commercial (70 d on feed).
• 15 % of cattle in Qld. are finished in feedlots.
• Industry expanding - major retail stores require grain feed beef.
• Grain supply could be a problem.
• 70 % fed for 180 d or less.
Feedbunk Management
• Proper management will reduce metabolic disorders, such as, bloat, acidosis, laminitis and entrotoxemia.
• Most feedlot deaths are due to digestive and metabolic disorders.
• Most deaths occur in cattle which have been on feed for over 80 d.
• Acidosis is the most common nutritional disorder (any time up to 80 d on feed) .
ACIDOSIS
Symptoms: off feed, porridgy scours, dehydration, prostration & death
• Overfeeding of highly digestible carbohydrate rations.
• Streptococcus bovis - increases due to high CHO intake - CHO increases lactic acid which allows this species to proliferate.
Prevention
• Avoid fluctuating feed intake.
• Never let troughs run out of feed.
• Ensure sufficient trough space.
• Pen size - not too large (or small) ~ 16 m2/hd.
• Fresh and palatable.
• In front of the animal 24 h/d*.
• Ensure feedbunks are nearly empty before placing fresh feed on top.
- spoilt feed will reduce intake, cattle will go hungry and over eat at next
• Feeding Most rations - 12 h freshness in bunks.
• Wet rations (> 15% water) - feed out 2x/d.
Assessing cattle intakes
At feed delivery observe the following:
• bunks are near empty but cattle are not aggressive (bunks should not be empty for more than 30 min/d - some debate on this).
• 25 % of cattle at bunks, 50 % standing, 25 % getting up.
• Consistent timing of feeding important - within 10 min each day.
• Ensure even distribution of feed - cattle tend to eat from same area of bunk.
• Clean out bunks at least every 3 d - more if it rains.
• Clean water troughs regularly - fermenting grain will foul water - reduces intake.
• When changing grains do so gradually 7 - 10 d change over.
Feedlot rations
• Starter and finisher rations.
• Grain to roughage ratios from 70:30 to 100:0.
• High grain - better FCR and weight gain.
• Processing roughage - expensive. Additional roughage may not be added to finisher rations.
• Starter rations - allow rumen to adapt to decreasing roughage.
• Finisher - formulated around grain with limited roughage.
• Fibre content - starter 16 %, finisher 5 %.
• Crude protein - starter 16, finisher 11 %.
• Energy - 9.5 to 11.5 MJ ME/kg.
• Energy requirements for feedlot cattle should be discussed in terms of Net Energy.
• Need to consider Net Energy for maintanance (NEM), and Net Energy for growth (NEG).
• NEM - 7.25 to 9.94 MJ/kg.
• NEG - 4.25 to 6.80 MJ/kg.
Grains
• Two groups of grains:
• Group 1 - sorghum & maize
• Group 2 - wheat, barley & triticale
• Group 1 - escape degradation in the rumen - starch is absorbed in small intestine. Gives better growth rate.
• Group 2 - fast digestibility in rumen - more likely to see metabolic disorders.
Buffers in Ration Feedlot
• Na bi-carbonate (best) & sodium bentonite (clay).
• More useful with Group 2 grains & when crude protein >14 %.
• Cattle on high CP diets do not chew cud as much, less saliva to rumen (11 % best for rumen, 13 % best for gain).
• Rumensin (monensin) - best?? - it is a coccidiostat (important in weaners), controls acidosis and bloat and leads to greater growth (5%).
• Avotan & Bovatec - 10 - 15% improvement in growth.
• Virginiamycin - reduces acidotic problems.
Vitamins
• Fat soluble vitamins are destroyed in the acidic conditions in the rumen of grain fed cattle.
• Damage to the liver (esp. wheat feeding) may cause reduction in Vit D uptake.
• Therefore - inject with ADE.
• Thiamine (B12) may be needed as there is some evidence of blindness - due to change in VFA production
SUMMARY - 6 R’s
• Right feed - high quality ration.
• Right pens - appropriate feed for cattle in pens.
• Right amount.
• Right time - consistent timing
• Right way - good feed placement & bunk hygiene.
• Read bunks.