Pasture & Range: December 2002

Introduction
Value-based marketing has stimulated interest in source and process verification and calf preconditioning programs across the country. The stocker cattle industry is a vital part of Oklahoma's agricultural economy, and sickness in freshly-weaned calves costs the stocker industry millions of dollars annually. Unfortunately, little information has been published documenting the value of process verification and preconditioning for stocker cattle. The purpose of this case study is to determine health and performance effects of the Oklahoma Quality Beef Network (OQBN) preconditioning and process-verification system for stocker cattle grazing cool-season annual pasture from March through May, and their performance in the feedlot. The following results represent the Year 1 stocker phase of a three-year study.

Methods
The study is being conducted at the Noble Foundation's Pasture Demonstration Farm (PDF) near Ardmore, Okla. Treatments are weaned, process-verified (PV) steers and non-process-verified (NPV) steers and bulls. For the purpose of this study, process verification was defined as the application, documentation and certification of a standardized management protocol about the time of weaning. Non-process-verified cattle had no documentation of vaccinations, weaning or other management procedures before they were purchased.

One professional order buyer purchased both groups of cattle through public livestock auction facilities. The PV cattle were purchased on Feb. 28 at the OKC West livestock marketing facility near El Reno, Okla. Pay weight was 496 pounds and average cost was $108.33/cwt. Livestock weights and prices are shown in Table 1. Only cattle certified to meet OQBN requirements were purchased. These requirements include a minimum of 45 days weaned, castration, dehorned or tipped, two rounds of modified live respiratory complex vaccine administered a minimum of 14 days apart, pasteurella hemolytica vaccine and a 7-way clostridial vaccine. The cattle also were fed a concentrate supplement for a minimum of seven days beginning at weaning.

Before the auction, all the certified OQBN cattle were sorted and commingled into uniform groups with a weight range of about 75 pounds within each group. Only cattle in the 425- to 500-pound weight class were purchased for this project. The cattle were shipped to PDF on the same day and provided overnight access to water only. On the morning of Feb. 29, the cattle were individually weighed, treated for external and internal parasites using Ivomec-Plus®, branded, and turned out on wheat pasture.

From March 6 to March 13 65 NPV steers and 83 NPV bulls of similar breed types, quality, flesh and weight were purchased from six livestock markets in southern Oklahoma and cost $102.12/cwt, weighing an average of 508 pounds per head. The NPV calves cost an average of $17.19 per head less than the PV steers. Purchase of the NPV cattle was intentionally delayed until after the purchase of PV cattle so that similar quality and weight cattle could be procured. Each time a group of NPV cattle were purchased, they were shipped to PDF on the same day, rested overnight with access to water only, and processed the next morning. Processing included individual weights, individual identification with an ear tag, branding, dehorning and castration when necessary, vaccination with a modified live respiratory complex, 7-way clostridial and pasteurella hemolytica, and treatment of internal and external parasites using Ivomec-Plus™. After processing, each group of cattle was turned out to graze in the same wheat pasture with the PV cattle.

On March 26, the cattle were penned at 4 p.m. and maintained overnight in a dry lot with no access to feed or water. On the morning of March 27, all cattle were individually weighed and NPV cattle received booster vaccinations of the modified live respiratory complex vaccine. Individual weights were also recorded on April 24 and May 30 using the same procedure. The cattle were monitored daily and all treatments for health problems were recorded. During the receiving and growing phases, total health costs were $15.67/hd for the NPV calves and $4.99/hd for the PV calves, for a difference of $10.68.

The cattle were rotated through 14 paddocks, averaging 11 acres each. Abundant forage was available at all times, averaging 7 inches during March and 13 inches during April and May. On June 5, the cattle were valued at $81.38/cwt, weighing an average of 693 lbs/hd and shipped to a feedlot where their performance is still being monitored.

Results
Receiving weights and performance results are shown in Table 1. Process-verified steers averaged 18 lbs. less than NPV bulls and steers upon arrival. Shrink from purchase weight to processing weight at the farm for the PV calves was 4.7 percent compared to 3.6 percent for the NPV calves. Cattle received as bulls lost weight slightly during the first few weeks of the grazing period compared to positive weight gain for both NPV steers and PV steers. The difference in NPV and PV weight gains should be viewed with caution simply because NPV cattle were received an average of nine days later. Therefore, the NPV cattle may not have been as well adapted to wheat pasture by this time compared to PV cattle. Non-process-verified and PV steers continued to gain faster than NPV bulls during April, although this trend was reversed during May.

However, when cumulative gain was calculated for the grazing phase (average grazing days = 87), NPV steers had significantly faster rate of gain compared to NPV bulls, and PV steers gained faster compared to NPV steers.

Five PV steers were treated for pink eye and three were treated for foot rot during the course of the study. One NPV steer was treated for foot rot and one NPV bull was treated for pink eye. Ten NPV bulls, three NPV steers and none of the PV steers were treated for respiratory disease.

Overall, the incidence of respiratory disease was minimal in these calves. This is probably due to the time of year that the cattle were received. These cattle are currently being finished in a commercial yard. Individual feed yard performance and carcass characteristics will be reported in a similar manner. It will be interesting to see if the cattle received as bulls will continue to make up the poorer performance during the early grazing phase.

*David Lalman in an assistant professor at Oklahoma State University and an Extension beef cattle specialist.