Microclimate Effects on the Temporal/Spatial Distribution of Beef Cows Grazing Cool-Season Grass Pastures by Different Management Practices

Florida has 915,000 beef cows and 125,000 replacement heifers (USDA, 2016). Developing these heifers so that they can become productive females in the cow herd is a tremendous investment in a cow/calf operation, an investment that takes several years to make a return. The good news is that there are options to develop heifers on forage-based programs with the possibility of reducing costs while simultaneously meeting performance targets required by the beef industry. Mild winters in Florida allows utilization of cool-season forages that can significantly enhance the performance of grazing heifers. During the warm-season, integration of forage legumes into grazing systems will provide additional nutrients to meet the performance required to develop a replacement heifer to become pregnant and enter the mature cow herd. In this document, we will propose a model for replacement heifer development, based on forage research performed in trials at the NFREC Marianna.

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Summer Dormancy Trait as a Strategy to Provide Perennial Cool-Season Grass Forage Alternatives in Southern Latitude Environments Affected by Climate Change

Agronomy Journal ◽

10.2134/agronj14.0628 ◽

2015 ◽

Vol 107 (4) ◽

pp. 1227-1234 ◽

Cited By ~ 1

Author(s):

Dariusz P. Malinowski ◽

William E. Pinchak

Keyword(s):

Climate Change ◽

Cool Season ◽

Southern Latitude ◽

Summer Dormancy ◽

Cool Season Grass

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PSXIII-2 Effect of varying proportions of cereal rye and turnip on ruminal fermentation and methane output through in vitro batch culture

Journal of Animal Science ◽

10.1093/jas/skab235.818 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 461-461

Author(s):

Jordan L Cox-O’Neill ◽

Vivek Fellner ◽

Alan J Franluebbers ◽

Deidre D Harmon ◽

Matt H Poore ◽

...

Keyword(s):

Methane Production ◽

Dry Matter ◽

Ruminal Fermentation ◽

Variable Response ◽

Cool Season ◽

Cereal Rye ◽

Freeze Dried ◽

Main Effect ◽

Cool Season Grass

Abstract Ruminant animal performance has been variable in studies grazing annual cool-season grass and brassica monocultures and mixtures. There is little understanding of the fermentation mechanisms causing variation. The aim of this study was to determine apparent dry matter (DM) digestibility, methane, and volatile fatty acid (VFA) concentration from different proportions of cereal rye (Secale cereal; R) and turnip (Brassica rapa L.; T) (0R:100T, 40R:60T, 60R:40T, and 100R:0T) via in vitro batch fermentation. Freeze-dried forage samples from an integrated crop-livestock study was assembled into the four treatments with a 50:50 leaf to root ratio for turnip. Measurements were made following a 48 hr fermentation with 2:1 buffer and ruminal fluid inoculum. Data were analyzed using Mixed Procedure of SAS with batch (replicate) and treatment (main effect) in the model; differences were declared at P ≤ 0.05, with tendencies declared at > 0.05 but < 0.10. Rumen apparent DM digestibility (26.8%; overall mean) was not different among treatments. Methane production was less (P < 0.01) with inclusion of turnip ranging from 774 nmol/ml for 0R:100T to 1416 nmol/ml for 100R:0T. Total VFA production, acetate to propionate ratio, acetate, and valerate were not affected by forage treatments (117 mM, 1.45, 39.84 mol/100 mol, and 7.86 mol/100 mol, respectively; overall mean). Propionate, isobutyrate, and isovalerate concentrations were greater and butyrate concentration less with greater (P < 0.01) proportions of rye in the mixture. No effect of R:T ratio on digestibility or total VFA production along with the observed differences in individual VFA concentration do not explain variable response in grazing animals. Additionally, methane production results indicate that grazing turnips could potentially reduce methane production and thus reduce ruminant livestock’s contribution to greenhouse gas emissions.

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Epichloë Endophyte Infection Rates and Alkaloid Content in Commercially Available Grass Seed Mixtures in Europe

Microorganisms ◽

10.3390/microorganisms8040498 ◽

2020 ◽

Vol 8 (4) ◽

pp. 498

Author(s):

Jochen Krauss ◽

Veronika Vikuk ◽

Carolyn A. Young ◽

Markus Krischke ◽

Martin J. Mueller ◽

...

Keyword(s):

Fungal Endophytes ◽

Grass Species ◽

Infection Status ◽

Infection Rates ◽

Cool Season ◽

Infected Seed ◽

Toxic Alkaloids ◽

Cool Season Grass ◽

Epichloë Endophyte ◽

Seed Mixtures

Fungal endophytes of the genus Epichloë live symbiotically in cool season grass species and can produce alkaloids toxic to insects and vertebrates, yet reports of intoxication of grazing animals have been rare in Europe in contrast to overseas. However, due to the beneficial resistance traits observed in Epichloë infected grasses, the inclusion of Epichloë in seed mixtures might become increasingly advantageous. Despite the toxicity of fungal alkaloids, European seed mixtures are rarely tested for Epichloë infection and their infection status is unknown for consumers. In this study, we tested 24 commercially available seed mixtures for their infection rates with Epichloë endophytes and measured the concentrations of the alkaloids ergovaline, lolitrem B, paxilline, and peramine. We detected Epichloë infections in six seed mixtures, and four contained vertebrate and insect toxic alkaloids typical for Epichloë festucae var. lolii infecting Lolium perenne. As Epichloë infected seed mixtures can harm livestock, when infected grasses become dominant in the seeded grasslands, we recommend seed producers to test and communicate Epichloë infection status or avoiding Epichloë infected seed mixtures.

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