2019 Cooperative Dairy Students (CUDS) Reunion

This year will be the 41st year of the existence of Cooperative University Dairy Students or CUDS. The advisory team would like to invite to a celebration on Saturday January 26, 2019 at the Ensminger Pavilion on the WSU Pullman campus.

We are in the initial planning stages in regard to specific plans and will share more this fall.

Please reply and indicate your interest in attending, and also forward names and e-mail addresses for members that you know so that we can add them to our mailing list.

Thanks.

Joe Harrison, Amber Adams-Progar, and Amber Merk
CUD Advisors

Joe Harrison, Livestock Nutrient Management Specialist, jhharrison@wsu.edu

New Publication Tackles Approaches to Nutrient Recovery from Dairy Manure

Interested in learning more about emerging technologies for separating nutrients from dairy manure? WSU’s Center for Sustaining Agriculture and Natural Resources has a new publication that summarizes the various approaches being explored for nutrient recovery on dairies – and what we know about the current costs and performance that are associated with each strategy. The publication, Approaches to Nutrient Recovery from Dairy Manure, was a long term effort by Craig Frear (formerly of WSU CSANR), Jingwei Ma (a WSU graduate student), and Georgine Yorgey (WSU CSANR). This publication is a companion to The Rationale for Recovery of Phosphorus and Nitrogen from Dairy Manure.

WSU’s Center for Sustaining Agriculture and Natural Resources has worked on various aspects of anaerobic digestion and nutrient recovery for a number of years. Please visit our Anaerobic Digestion topic page for additional publications, videos, and resources, including links to our Anaerobic Digestion Systems Extension Publication Series.

Georgine Yorgey, Associate Director, Center for Sustaining Agriculture and Natural Resources, yorgey@wsu.edu

Hoof Care: Beware Too Much of a Good Thing

Hoard’s Dairyman hosted a webinar called “Supervise Hoof Health with a No Lameness Tolerance Policy” on June 11, 2018. The presenter was Karl Burgi, professor emeritus at the University of Wisconsin-Madison School of Veterinary Medicine and Program Director at the Dairyland Hoof Care Institute, Inc. This article will be a synopsis of the portion of that webinar related to hoof trimming; readers are encouraged to view the entire archived webinar at https://hoards.com/article-23342-supervise-hoof-health-with-a-&lsquono-lameness-tolerance-policy.html. Photos used here are from that webinar and used with permission.

Rates of lameness in cows producing over 90# milk/day on U.S. dairies ranges from 13.2 to 54.8%, with a mean of 25%. This huge variation is due to differences in management and factors affecting cow comfort on different farms, of course, but also attitudes about lameness. Some managers react to individual lameness cases; others recognize the effects of lameness on production and animal comfort and devote resources to prevention measures.

A 2017 study calculated the per-case cost of lameness at $527 per cow, which also includes pro-rated death and culling losses. A study of digital dermatitis (DD, a.k.a. hairy heel warts) in heifers revealed affected animals averaged 750 fewer pounds of milk over their first lactation and were open 28 more days than unaffected heifers. Lameness is also responsible for a 20% increase in premature culling and 2% death rate.

Lameness in early lactation is particularly costly because it affects peak lactation and lactation curves. Plus, if a cow becomes lame, the risk of recurrence is increased in subsequent lactations. This is because lameness and its predisposing factors can cause permanent changes to the skin, fat pad, ligaments, and bones of the foot. Therefore, a lameness management program should emphasize prevention for greatest success.

Lameness can be assessed on dairies by hoof lesion scores, locomotion scores (3-, 4-, and 5-point scale systems are available), management software, and/or hoof health analysis. The main foot lesions are DD, sole ulcers, white line disease, thin soles/toe ulcers, and foot rot. If DD is reduced, all other types of lesions will be reduced as well. The presentation includes recommendations for DD treatment and control not discussed here.

There are two types of hoof trimming: functional (routine to deal with hoof growth and maintain proper weight-bearing angles and surfaces) and therapeutic (treatment of issues causing lameness). Mr. Burgi states when it comes to functional trimming, “less is more” but “more is better” for therapeutic trimming. Ironically, hoof trimming may be a causative lameness factor if lameness cases persist in spite of addressing the following issues successfully:

  1. Cows are handled properly by crowd gates and humans (i.e., not rushed).
  2. Cow comfort is addressed and cows spend at least 12 hours lying down daily.
  3. Effective hoof baths are installed, used, and maintained properly (see webinar).
  4. Cows have secure footing on floors.
  5. Heat abatement measures are taken when needed to encourage lying time.
  6. Cows spend less than 2.5 hours/day out of pens (3× milking).

For each animal, assess the need for hoof trimming 3 to 8 weeks pre-calving and 1 to 3 times during lactation, or more often depending on the environment and an animal’s history. Routinely check first-calf heifers by 4 months into lactation. Note problem animals requiring more frequent monitoring in a computer management or other record-keeping system.

Pastured springing heifers should be brought in from pasture about 2 months before calving to give them time to develop protective fat pads in their feet and adjust to concrete. Their feet should be examined and trimmed at this time. Springing heifers stand significantly more time than cows. Standing on overgrown or improperly trimmed hooves will result in inflammation, which can predispose heifers to sole ulcers and a shortened productive life. Inflammation appears as redness in the sole (Photos 1 and 4); redness also means there is no overlying protective sole in that area.

Hoof trimming should not cause lameness, reduce cow welfare, or prevent lame cows recovering from their initial problem. Hoof trimming mistakes include:

  1. Trimming hooves too short. Normal claws should be 3” long with about ¼” sole thickness.
  2. Over-trimming heels, which changes (lowers) the angle where toes meet the ground (Photo 1); sole ulcers and white line disease can result.
  3. Grinding or otherwise over-trimming claw walls (Photo 2). The wall is weight bearing; grinding removes the wall and permanent P3 (coffin bone) remodeling and loss will follow. Never remove the wall unless the animal is lame and the wall is involved—in such a case, apply a hoof block after trimming.
  4. The sole is ground down excessively (Photos 3 and 4). Less than ¼” sole thickness causes inflammation resulting in sole ulcers and lameness. Soles can be ground away during excessive hoof trimming or by harmful environmental conditions (coarse sand, poor grooving, and exposed cement aggregate).
  5. Leaving claws unbalanced.
  6. Sole is not left flat.
Cow hoof displaying over-trimming on the heel (left) vs a well trimmed hoof (right).
Photo 1. Left photo shows over-trimmed heels causing undesirable low angle at toe, which changed the angle of weight bearing (dashed black line). Right photo shows targeted trimming preserving heel depth, which maintained proper toe angle. This resulted in good weight bearing through the entire foot bone structure with even weight distribution throughout the claw. Note how sole was pared away on right claw to remove weight-bearing surface over an inflamed area (yellow arrow) so this area can heal, similar to applying a block to the good claw. The green arrow and line denote where pressure is born on the sole: concentrated on the left photo due to low toe angle, which predisposes to sole ulcer and lameness; well distributed over the entire sole on the right.
Cow hoof displaying excessive trimming to the claw walls.
Photo 2. A “pretty hoof” post-trimming, but excessive wall was needlessly ground away, reducing the proper and normal weight-bearing tissue for this animal.
Cow hoof displaying excessive removal across the entire hoof, bleeding at toe.
Photo 3. Another “pretty foot” post-trimming where too much emphasis was placed on making a level weight-bearing surface. Note results of excessive grinding: so much protective sole has been removed that blood was drawn at toe; in that area, human interference has remove all the sole. A toe ulcer and lameness will follow. Weight-bearing wall tissue was also ground away needlessly.

Inflammation occurs before lameness. Some factors increasing the risk of inflammation include:

  • Calving—stressful time for all cows and heifers; any pre-calving foot issues are exacerbated after calving
  • Excessive standing—reduces hoof circulation, which affects hoof health; secondary to overcrowding, too much time in head catches or holding pens, heat stress, or uncomfortable beds
  • Delayed treatment—lets DD become chronic, facilitates secondary ulcers and foot rot
  • Lack of trimming—causes trauma from abnormal forces on hoof structures
  • Improper trimming—removes protective tissues, damages healthy tissues, leaves imbalance causing abnormal weight-bearing forces
  • Lack of blocking of ulcers—affected tissues do not have time to heal and inflammation continues. Blocks take pressure off painful tissues and increase oxygen contact with hoof tissues, which can kill some hoof disease bacteria.

Hoof inflammation can be prevented or reduced by providing an adequate number of comfortable stalls; using heat abatement measures to keep cows comfortable while lying; investigating all lameness cases within 24 hours; and using anti-inflammatory medications based on veterinary recommendations. Also, hooves should be trimmed 3 to 8 weeks before calving so all close-up animals have proper hoof anatomy and function. Close-up and fresh cows should have excellent cow comfort, including no overcrowding. Lameness in close-up, calving, and fresh animals should be avoided at all costs due to the major negative effects on milk production and animal welfare.

Cow hooves show displaying ulcers in the toe area.
Photo 4. Toe ulcers secondary to thin soles. Thin soles are caused by over-trimming (especially grinding), rough floors, coarse sand, and too much time standing.

Due to their associated costs, long-term implications, and effects on animal well-being, lameness cases need to be investigated and addressed promptly. Few conditions causing lameness improve on their own and many can progress to career-ending ulcers, abscesses, or bone/joint infections in otherwise productive cows. Having a well-defined lameness program with designated trained people responsible for lameness detection and prompt treatment is essential, as is a record-keeping system to flag and record actions.

Resources

Susan Kerr, WSU Northwest Regional Livestock and Dairy Extension Specialist, kerrs@wsu.edu