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Jonathon
Beckett and Mike
Hall have both actively pursued research opportunities in the areas of range management and pharmaceutical use to improve growth of cattle.
Effects of Long-Acting Estrogen-base Growth Promotant on Growth and Performance and Carcass Characteristics in Holstein Steers.
Beckett, Jonathon L.
 The use of growth-promoting implants in the United States
is widespread, although optimization of compound type and onset of implant
exposure has not been completely resolved. In particular, although implants
dramatically increase average daily gain (~10%) and feed efficiency (~15%),
there is evidence that implants decrease quality grades (Prime, Choice,
Select and Standard) and tenderness of the meat. The preponderance of
research has been conducted on traditional beef cattle genetics. While
the vast majority of the cattle fed in the United States are of traditional
beef cattle background, there are a large number of steers that enter
feedlots as byproducts of the dairy industry. Indeed, California places
approximately 600,000 Holstein steers in feedlots annually. Due to the
profound differences in growth characteristics between dairy breeds and
cattle of more traditional beef genetics, the Holstein steers are fed
for a longer period of time and thus are subjected to repeated implant
regimens. The implementation of repeated, serial implants can result
in losses in efficiency and growth as the animals are processed more
frequently, and are subject to more injury due to the more frequent handling.
As more investigators report on the interaction between genetic influences
and implant effects, there is growing concern that traditional implant
regimens are not adequately tested in Holstein steers, particularly as
they relate to season of placement. The objective of the proposed research
is to test the efficacy of a long-lasting, sustained release estrogen
implant, singularly, and in combination with other growth promotants.
Specifically, the following responses will be measured: (1) effect on
growth and efficiency characteristics, (2) influence on quality grade,
yield grade, dressing percent and ribeye area, and (3) effect of season
on implant regimen. The working hypotheses of the proposed research are
(1) A long-acting estrogen implant can be used in a growth promoting
strategy (which limits the number of times the cattle must be handled), maintains the rapid growth and high efficiency of other implant regimens, yet minimizes the detrimental effects of implants on carcass quality. (2) Different strategies are appropriate depending on the season of placement into the feedyard.
Effects of Varying Initial Implant on Growth & Performance, Carcass Characteristics, & Meat
Tenderness in Holstein Steers
Beckett, Jonathon L.
 The use of growth-promoting implants in the United States is widespread,
although optimization of compound type and onset of implant exposure has
not been completely resolved. In particular, although implants dramatically
increase average daily gain (~10%) and feed efficiency (~15%), there is
evidence that implants decrease quality grades (Prime, Choice, Select and
Standard) and tenderness of the meat. The preponderance of research has
been conducted on traditional beef cattle genetics. While the vast majority
of the cattle fed in the U.S. are of traditional beef cattle background,
many steers enter feedlots as byproducts of the dairy industry. Indeed,
California places approximately 600,000 Holstein steers in feedlots annually.
Due to the profound differences in growth characteristics between dairy
breeds and cattle of more traditional beef genetics, the Holstein steers
are fed for a longer period of time and thus are subjected to repeated implanting
regimens. As more investigators report on the interaction between genetic
influences and implant effects, there is growing concern that traditional
implant regimens are not adequately tested in Holstein steers. The objective
of the proposed research is to test the temporal effect of initial implant
exposure in feedlot Holstein steers. Specifically, the following responses
will be measured: (1) effect on growth and efficiency characteristics, (2)
influence on quality grade, yield grade, dressing percent and ribeye area,
and (3) determine the effect of implant timing on meat tenderness. The working
hypothesis of the research is that the optimal time of implant exposure
onset can be identified to optimize the increased gain and efficiency while
minimizing the detrimental effects on carcass quality.
Efficacy of Pour-on Dewormers Differing in Active Ingredient and Carrier
on Weight Gain and Fecal Egg Count in Stocker Cattle
Beckett, Jonathon L.
 Various
dewormers are prevalent in the beef cattle industry to increase productivity
and performance in cattle during all phases of growth. Factors influencing
the choice of dewormer and administration method include: type of
indigenous parasites, ease of administration, length of effectiveness
and cost. Although current dewormers are effective, they vary in duration
and cost. Previous studies suggest that weight gain is certainly influenced
by the choice of dewormer. This project is designed to appropriately
test the effects of differing dewormers and routes of administration; the
various dewormers must be tested against each other in a uniform group of
cattle, during one growing season, in a controlled situation. The cattle
arriving at Swanton Pacific Ranch from Hawaii typically are susceptible
to parasite infestation due to relatively high parasite load in the forage.
Approximately 500 head of cattle will be randomly assigned to 1 of five
treatment groups, including (1) Cydectin, (2) Ivomectin pour-on, (3) Eprinex,
(4) Dectomax, and (5) non-treated control. Initial treatment will be completed
at delivery to the ranch. Cattle will be retreated approximately 112
days after initial treatment. Cattle will be weighed monthly, and fecal
samples will be collected to determine egg counts. Larval cultures will
be completed to identify species of parasites. The working hypothesis for
this study is that increased productivity (weight gain) will be realized
in cattle medicated with the most effective dewormer and route of
administration, as indicated by fecal testing.
Effects of High Density-Short Duration and Open Cattle Grazing on Oak Woodland/Savanna Rangeland
Hall, Michael
 Evidence shows that grazing by domestic livestock plays an important role
in the ecological system of California's 40 million acres of rangeland.
Two different types of grazing regimens, high intensity-short duration (HISD)
and open grazing will be compared against no grazing to quantify the effect
that grazing has on forage diversity, productivity and quality. Limited
scientific research has been conducted to quantify the effect that grazing
has on our California ecosystem. The objective of this study will quantitatively
assess the impact of HISD on natural ecosystems, and particularly on the
oak/woodland savanna (OWS) rangelands that are so important to the cattle
industry in California. Specifically, the research will consist of quantitative
comparisons in grazed and ungrazed areas and will include detailed measurements
of the following: (1) beef production; (2) forage productivity and quality;
(3) soil quality, erodeability, and soil nutrient content; (4) pasture cover
and species diversity; and 5) natural oak recruitment. The working hypothesis
of the research is that good grazing practices will enhance forage production
and quality, therefore increasing beef productivity.
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