"Oof, my hoof."
- Digital dermatitis is the infection and inflammation of the hooves of cattle.
- The timing of the infection was compared to the animal's rumination and activity levels at that time.
- Heifers with digital dermatitis spent 3% less time per day ruminating and 3% more time inactive.
What you need to know: Digital dermatitis has nothing to do with the internet but a lot to do with feedlot profitability—digital, meaning fingers/hooves, and dermatitis, meaning swollen and blistered skin.
Digital dermatitis is the infection and subsequent inflammation of the claws of cattle and, in recent work, has been shown to impact the productivity of animals in a feedlot situation.
In a first-of-its-kind study, heifers at a feedlot in Alberta were observed for limping and noticeable hoof infections. These observations were used to record when an animal contracted digital dermatitis. The onset of the infection was compared to the animal's level of rumination and activity over the previous five days, using sensor data from a tag in the heifer's ear.
Prevalence of the infection was high, being found in 33 of the 84 heifers. Additionally, the sensor data found that dermatitis affects the animal's activity and rumination activity. The difference? Heifers with digital dermatitis spent 3% less time per day ruminating and 3% more time inactive. Decreased activity and rumination could hurt the average daily gain and feed efficiency of the animal.
The important asterisk*:
- The smaller number of animals used in the study could unintentionally skew data; however, it does not limit the value of the findings.
- Visual observations are hard to complete accurately, consistently due to human error. Because of this, some infections were likely missed or finding delayed.
Industry Application: Pen riding and training feedlot personnel to watch for digital dermatitis could be a valuable practice. Catching and treating the infection early ensures the animal can be more efficient and leave the feedlot sooner.
Read more about it: Impact of digital dermatitis on feedlot cattle behaviour.
The long and short of fescue toxicity
- Fescue toxicity has symptoms of restricted blood flow and reduced performance, like feed intake.
- Pregnant Charolais and Hereford grazed toxic fescue and had different levels of symptoms.
- Charolais appear to be more resilient to the effects of toxic fescue.
What you need to know: Fescue is a grass that is exceptionally drought tolerant but can also harbor toxicity during the summer months. Fescue toxicity, caused by endophyte-infections of the grass, has symptoms of restricted blood flow, retention of a thick hair coat, and reduced performance metrics like feed intake.
To improve the utilization of this grass, researchers have been searching for ways to blunt the effects of toxic fescue consumption. Pregnant Charolais and Hereford cows were put on either toxic on non-toxic fescue pastures for over 150 days to see if the two breeds had different levels of symptoms from the toxic fescue.
As expected, toxic fescue pastures impacted the productivity and health of all cows consuming the forage. However, Hereford cattle had greater breaths per minute and body temperature and lower mineral status and hair loss. Charolais appear to be more resilient to the effects of toxic fescue.
A primary finding was that hair retention of cows eating toxic fescue was also associated with higher body temperatures. Additionally, Herefords have greater hair retention than Charolais in this data, which was made worse by toxic fescue pastures—combined, suggesting that Herefords had more significant symptoms due to their natural hair retention being greater than Charolais.
The important asterisk*:
- The animals in this research only had access to water every other week, as they were on a pasture rotation that only allowed access to a pond intermittently. However, herds on toxic and non-toxic pastures both had limited water - suggesting the comparison is fair.
- Many of the measurements, like body weight, were only collected on two occasions; day 0 (the start of the trial) and day 156 (end of the trial). More measures across the trial length would be better, but that would be hard with the design.
Industry Application: When a ranch has toxic fescue, it could be beneficial for commercial producers to use cattle breeds that are less impacted, like Charlois and potentially other breeds with more ability to shed hair.
A win-win, but the punchline is a little corny
- A simple answer to increasing feed conversion rate may be using different corn varieties in cattle rations.
- Animals consuming the Enogen corn had better feed efficiency, which improves the environmental impact measures significantly.
- Both universities had decreased estimated land use from Enogen corn as a feedstuff.
What you need to know: Feed conversion rate is the magic phrase we select for with better genetics and chase after with nutrition supplements. Well... a simple answer may be using different corn in your rations. Enogen, from Syngenta, is a corn seed with amylase enzyme activity that helps starches in the corn digest more quickly than other corn varieties.
Researchers combined a Kansas State University backgrounding trial and a University of Nebraska Lincoln feedlot trial to measure feed efficiency and greenhouse gas emissions. Animals consuming the Enogen corn had better feed efficiency, which improved the environmental impact values significantly.
Both universities saw decreased estimated land use from using Enogen corn, with UNL and KSU being 6.13% and 5.17%, respectively. Estimated land use represents square meters of crops needed for 1000 kg of beef to be harvested.
There was also a decrease in estimated water use. The estimated water use of the feedlot decreased by 5.61%, and the KSU backgrounding unit decreased by 5.13%. Estimated water use is representative of cubic meters of water required for 1000 kg of beef to be harvested from the animals.
The important asterisk*:
- The backgrounding and feedlot cattle were not the same animals but instead separate groups.
- Greenhouse gas emissions rely on many assumptions as collecting all outputs and inputs would be impossible, not to mention extremely expensive.
Industry Application: Increasing the digestibility of rations by selecting more digestible corn varieties can increase the feed efficiency of animals. Additionally, it is important to note that the more feed-efficient animals are, the lower their environmental impact.
Reviewing Rumensin for Ranches?
- Ionophores are vital to the efficiency that we see in feedlots.
- Using these direct-fed antimicrobials can decrease the quantity of methane produced.
- Cattle producers outside the feedlot system may also derive value from ionophores.
What you need to know: Rumensin has many other "siblings" that are all part of the same group of ionophores. These direct-fed antimicrobials are vital to the efficiency that we see in feedlots today, with ionophores increasing dry matter intake by upwards of 3% and average daily gain by more than 2%.
Coinciding with the greenhouse gases discussed above, using these direct-fed antimicrobials decreases the quantity of methane produced by between 2 and 15%.
The adoption of ionophores by grazing systems is currently low due to concerns of toxicity, labor, efficacy, microbial adaptation, etc. However, data suggests that in the case of a grazing system, ionophores could be supplemented every other day and maintain nearly all the effects as feeding daily. Limiting the chance of toxicity of the animals and decreasing the labor required to supplement the product.
Animals supplemented for 240 days have shown consistent and lasting effects from supplementation of ionophores, suggesting long-term use does not limit effectiveness. Additionally, research has been published demonstrating that moderate-quality, forage-only diets are also positively impacted by ionophores.
Industry Application: Ionophores are useful in feedlot performance as well as reducing methane emissions. Cattle producers outside the feedlot system could also derive value from ionophores.
Read more about it: Effects of Ionophores on Ruminal Function of Beef Cattle