This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the October 23, 2017 issue of Canadian Cattlemen magazine and is reprinted on the BCRC Blog with permission of the publisher.
Getting weaned calves on feed can be a challenge. This is often attributed to the change from a forage-based diet to unfamiliar feedlot rations and feed bunks, distress from recent weaning, illness, etc. To compensate for this, some feeders use a relatively high-energy receiving diet, the rationale being that if they’re not going to eat much, each mouthful better pack a nutritional punch. But part of the challenge these calves face may be complications from feed deprivation during marketing and transportation. Recent research led by the University of Saskatchewan’s Greg Penner suggests that the rations fed both before and after feed restriction affect how well cattle cope with and recover from these challenges (J. Anim. Sci. 91:4730-4738 and 91:4739-4749).
What they did: This study used Continue reading
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the March 2017 issue of Canadian Cattlemen magazine and is reprinted on the BCRC Blog with permission of the publisher.
Grain-based diets improve feed efficiency, but increase the risk of rumen acidosis. Rumen acidosis occurs when rumen pH drops below 5.6 for more than 3 consecutive hours. Severe or chronic acidosis is an animal welfare concern due to rumen damage, liver abscesses, lameness, and an economic cost due to compromised feed conversion and growth performance. Consequently, feedlot operators manage their feed bunks and feeding programs very carefully, particularly as cattle transition from forage-based backgrounding to grain-based finishing diets. The risk of acidosis is influenced by grain type (wheat being a higher risk than corn, with barley being intermediate), the extent of grain processing, feeding frequency and bunk management. Group size and pen density are also factors, so research trials using individually fed animals may produce Continue reading
To optimize productivity and prevent sickness, management of rumen health is important on operations from cow-calf through to feedlot. The rumen is full of a diverse group of bacteria that break down fibre and help with digestion. To maintain rumen health, the bacterial population needs to be diverse and able to effectively break down feed.
When pH levels in the rumen drop too far, fibre digestion decreases, nutrient absorption is reduced, and the lining of the rumen is damaged. Acidosis also leaves cattle more susceptible to disease.
The number one key to maintaining a healthy microbial population is to ensure a constant dry matter and nutrient supply to the rumen, but of course this is easier said than done. Cattle inevitably vary their dietary intake when they are calving, being transported, are sick or hunkered down in storms.
Cattle and other ruminants are able to digest grasses and other fibrous material because of the billions of bacteria, fungi and protozoa in the rumen. Each of these microbes has a preferred food source. For example, some prefer fibrous materials, whereas others prefer starch. Regardless of their preferred feed source, all bacteria beak down simple sugars to volatile fatty acids such as acetate, propionate, and butyrate. These volatile fatty acids are absorbed through the rumen wall into the bloodstream and provide an important energy source for cattle.
As their names suggest, volatile fatty acids are acidic under normal pH conditions in the rumen. As a result, rumen pH varies with volatile fatty acid concentrations in the rumen. Rumen pH drops as feed is digested rapidly, and rises when the rate of digestion slows. Normally, the production and utilization of volatile fatty acids is in balance. Ruminal acidosis occurs when acid is produced faster than it can be utilized.
Ruminal acidosis is a digestive disorder that is characterized by low rumen pH (more acidic than normal). Typically acidosis is said to be a pH below 5.8 (normal rumen pH is 6.5 – 7.0).
Cattle are at greatest risk for acidosis when consuming feed that is high in fermentable carbohydrates, which is most commonly associated with feedlot rations but can also happen on high quality pasture. Cattle that go off feed for an extended period of time are also at risk when they resume feed intake.
Click to continue reading… more information on the types, causes and prevention strategies of ruminal acidosis in beef cattle.
Update: Missed the webinar? Find the recording and check for future webinars on our Webinars page: http://www.beefresearch.ca/resources/webinars.cfm
When the digestive system isn’t balanced and functioning properly, cattle’s feed intake and ability to utilize nutrients may decline, and the likelihood of
health problems and carcass value discounts can increase. A better understanding of the rumen can help to prevent or resolve problem situations and manage feeding to economically meet production goals.
Join this free webinar to learn about:
- what is rumen health: balancing the needs of the microbes and beef cattle
- the direct and indirect links of rumen health and productivity
- strategies to optimize rumen health and productive outcomes
Feed efficiency and cost of gain strongly impact feedlot profitability. Feed efficiency is thought to decline with advancing days on feed, though factors contributing to this are unclear. Understanding changes in feed efficiency over the course of the finishing period may identify opportunities to further improve feedlot production efficiencies.
Research currently underway and funded by the National Check-off and Canada’s Beef Science Cluster is working to improve Continue reading
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the August 2014 issue of Canadian Cattlemen magazine and is reprinted on the BCRC Blog with permission of the publisher.
Some rumen microbes prefer to break down fiber, while others thrive on sugars and starches. This allows cattle and other ruminants to take advantage of a wide variety of different feeds. If the feed contains a lot of poorly digestible fiber, the fiber digesting microbes will predominate. This allows ruminants to survive in Canada’s long, cold winters. Other rumen microbes dominate when plants are growing rapidly in spring and contain a lot of sugar and easily digestible fiber. These more digestible feeds provide energy and protein to the animal more quickly, and deliver the nutrients needed to allow them to produce milk, recover body condition, grow, and rebreed quickly and efficiently during Canada’s relatively short growing season.
The cells lining cattle’s digestive tracts have two seemingly contradictory functions: they need to absorb nutrients while also acting as a barrier to prevent disease causing organisms from entering the bloodstream.
Nutrient absorption has not been studied in great detail in ruminants, and barrier function even less so. The interplay between these two functions also raises the possibility that nutritional disruptions may also affect how well the gut can act as a barrier to pathogens.
Research currently underway, funded by the National Check-off and Canada’s second Beef Science Cluster, is working to better understand Continue reading
Acidosis refers to a lower than normal pH in the rumen. It is a growth performance, health and welfare concern caused by highly fermentable feed being digested too quickly, and typically seen when cattle are moved from a predominantly forage-based to grain-based diet. Cattle that engorge on forages are also at risk.
Acidosis can cause diarrhea, reduced feed intake, and depressed behavior. Once an animal recovers, it is likely to be feed deprived, leading it to overeat and be susceptible to more severe acidosis. Severe acidosis can lead to rumen ulcers, which allow bacteria into the blood stream causing further health problems, and death.