Florida Cattle Research Articles

An empirical predator‒prey model: Examining the interaction of Florida panthers, white‐tailed deer, and cattle in Florida

AbstractIn this article, we present a predator‒prey model for Florida panthers (FL panthers), white‐tailed deer (deer) and cattle in Florida. The model is used to construct the following four policy scenarios: (a) joint management of all three species (Scenario 1); (b) a target population size of FL panthers of 240 individuals (Scenario 2); (c) a target population size of FL panthers equal to the carrying capacity (Scenario 3); and (d) a target population size of FL panthers of zero (Scenario 4) (Scenario 4). We parameterized the model for FL panthers, deer and cattle in Florida, which enables us to obtain empirical results for the population, harvest and net benefit of all three species under each policy scenario. When comparing Scenarios 1 and 2, the total net benefit of all three species is only slightly higher in the former case. Under Scenarios 3 and 4, the net benefit of deer changes significantly compared to Scenario 1, while the effect on the net benefit of cattle is minor. When comparing Scenario 1 and an actual situation, we find that the optimal population of FL panthers is only slightly higher than the actual population.

Assessment of statewide and within-herd seroprevalence of Anaplasma marginale antibodies in 12 Bos taurus–Bos indicus cow herds and the association with sporadic outbreaks of bovine anaplasmosis in Florida

Our objective was to assess within-herd seroprevalence of Anaplasma marginale antibodies across 12 Florida beef cattle herds and compare with statewide seroprevalence. Twelve surveyed herds ranged in size from 160 to 456 adult Bos taurus – Bos indicus cattle. Statewide A. marginale seroprevalence relied on blood samples obtained at slaughter from 201 Florida cattle. Screening relied on competitive ELISA. Before serology, an outbreak of anaplasmosis resulted in increased mortality (up to 17.8%) and abortions in several herds. Up to 29.2% of cows aborted late in gestation in 2 herds that included many cattle introduced from Texas. Among 1,085 cattle tested in the 12 herds, seroprevalence of A. marginale varied from 2.6 to 85%, with an overall seropositive rate of 50.3%. Cattle in open herds were 6.23 (95% CI: 4.26–9.17) times more likely to experience mortality and 3.10 (95% CI: 2.39–3.98) times more likely to abort than animals in closed herds. Average mortality (12%) and abortion (16.3%) among open herds were significantly ( P < 0.05) higher than mortality (1.9%) and abortion (5.3%) among closed herds. Overall seropositivity among affected herds was higher than the apparent statewide seroprevalence of 20.32%. This survey provides estimates of seropositivity among Florida cattle and reports the absence of uniform herd immunity in an area considered endemic for bovine anaplasmosis. These data highlight unrestricted cattle movement and environmental conditions that favor vector-borne disease transmission as risk factors for disease outbreaks even in regions that are considered endemic for bovine anaplasmosis.

Epidemiology of Bluetongue Virus and Epizootic Hemorrhagic Disease Virus in Beef Cattle on a Ranch in South-Central Florida.

Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) infect a variety of wild and domestic ruminant hosts in the United States, with outcomes ranging from subclinical infection to clinical disease resulting in mortality. Because cattle have been suggested as a temporary reservoir for both BTV and EHDV, ongoing national surveillance for these viruses may benefit from inclusion of domestic cattle as a supplement to current programs, such as surveillance of wild white-tailed deer. To better understand the prevalence of BTV and EHDV in cattle, we surveyed for viral RNA (vRNA) in the blood of 1,604 beef cattle on a south-central Florida cattle ranch over 3 years. While overall prevalence of vRNA in blood was low (<2% for either virus), the occurrence of vRNA was much higher in young animals: in 2016, 24% of animals 2 years old were positive by PCR for either BTV or EHDV. Our results suggest that cattle are a likely temporary reservoir for these viruses in Florida, and could provide additional information on the spatial distribution, viral diversity, and timing of emergence of these viruses, particularly if surveillance was restricted to cattle ≤2 years of age.

Wild pigs as sentinels for hard ticks: A case study from south-central Florida.

As a result of shifts in the habitable range of ticks due to climate change and the ongoing threat of exotic tick species introductions, efficient surveillance tools for these pests and disease vectors are needed. Wild pigs are habitat generalists, distributed throughout most of the United States, and often hunted recreationally or removed as part of management programs, making them potentially useful sentinel hosts for ticks. We compared ticks collected from captured wild pigs and standard tick dragging methods on a south-central Florida cattle ranch from May 2015–August 2017. Three hundred and sixteen wild pigs were surveyed, and 84 km spanning three habitat types (seminative pasture, improved pasture, and hammock) were dragged. In total, 1023 adults of four species (Amblyomma auricularium, Amblyomma maculatum, Dermacentor variabilis, and Ixodes scapularis) were collected from wild pigs, while 39 adults of three species (A. auricularium, A. maculatum, and I. scapularis) were collected from drags. Only one immature specimen, a nymph, was collected from a pig, while dragging collected 2808 larvae and 150 nymphs. Amblyomma maculatum comprised 96% of adults collected from pigs, while A. maculatum, I. scapularis, and A. auricularium comprised 38%, 33%, and 28% of adults collected from drags, respectively. Adults of all tick species found on drags were found on pigs, and wild pig surveillance detected adults of an additional species not found on drags. Dragging was far superior for collection of immatures but not for adults of most species found in this study. These findings suggest wild pigs could be used as a sentinel for the detection of tick species. When combined with ongoing wild pig research, hunting, or management, wild pig surveillance can provide an effective method to survey for adult tick presence of some species of interest and may assist in tracking the range expansion of some tick species.

Managing South Florida Range for Cattle

This document states that South Florida's range management for cattle involves understanding the unique characteristics and historical context of the region's range types. The southeastern pine forest region, particularly Florida, has been utilized for cattle production since 1521 and is classified as the longleaf/slash-pine/wiregrass range type. The state has approximately 3 million acres of range, primarily forested in the northern half, while two-thirds of Florida's cattle are found in the south. The Natural Resource Conservation Service (NRCS) recognizes 28 range sites in Florida, but only four are significant for cattle production in South Florida. The document highlights the importance of native grasses, distinguishing between "decreaser" grasses, which are preferred and decline with overgrazing, and "increaser" grasses, which are less desirable and increase with overgrazing. Range condition class, a traditional method of assessing range health based on the prevalence of decreaser grasses, is discussed alongside the more modern concept of rangeland health, which evaluates the integrity of soil, vegetation, water, and air. The document emphasizes the importance of available forage and its nutritive value, noting that Florida ranges typically support low cattle carrying capacities due to poor to fair range conditions. This document was first published in June, 2002.

Serologic evidence of exposure to influenza D virus among persons with occupational contact with cattle

BackgroundInfluenza D virus (IDV), a novel influenza virus with proposed classification: family Orthomyxoviridae, genus Influenzavirus D, species Influenza D virus, has been associated with influenza-like illness in cattle and swine. More recently, anti-IDV antibodies have also been detected in small ruminants. A seroprevalence of approximately 1.3% has been estimated for the general human population. ObjectivesTo gain insights on the zoonotic potential of IDV to human adults with occupational exposure to cattle in north central Florida. StudyA cross-sectional serological study was performed on human serum samples from 35 cattle-exposed and 11 non-cattle-exposed adults to screen for IDV antibodies using hemagglutination inhibition (HI) and microneutralization (MN) assays. ResultsA seroprevalence of 91% was detected via HI assay, and 97% by MN assay among individuals working with cattle in Florida. Among non-cattle-exposed individuals, seropositivity determined via MN assay (only) was lower (18%). ConclusionsIDV poses a zoonotic risk to cattle-exposed workers, based on detection of high seroprevalence (94–97%). Whereas it is still unknown whether IDV causes disease in humans, our studies indicate that the virus may be an emerging pathogen among cattle-workers.

Why Do Cattle Ranchers Participate in Conservation Easement Agreements? Key Motivators in Decision Making

When communicating with farmers and ranchers, land conservation professionals would be better equipped if they understood key influences on their target audience's decisions to permanently preserve their land from development. This study predicted key factors influencing rancher engagement in a conservation easement (CE) agreement. Specifically, theory of planned behavior, trust, environmental identity, past behavior, perceptions of specific CE characteristics and selected participant demographics were used as predictors. A mixed-methods approach was applied involving interviews, a two-phase pilot study, and a statewide mail-administered questionnaire. Final interview domains guided the quantitative survey instrument, which was administered to 1,000 Florida cattle ranchers. A 60% response rate was received. Multiple linear regression demonstrated ranchers were more likely to enter into a CE agreement if they 1) had a positive attitude about the outcomes associated with CEs; 2) felt influential others would positively support CEs; 3) indicated higher trust in conservation organizations and agencies; 4) believed their land had significant conservation value; 5) supported sale or donation of certain property rights; and 6) were positively influenced by financial incentives, primarily estate tax deductions. These six variables explained over 50% of intent to engage in a CE agreement. Understanding these influences will aid land conservationists in their future communication efforts with farmers and ranchers.

Economic Impact of Tropical Soda Apple (Solanum viarum) on Florida Cattle Production

A written survey administered to 3,500 Florida cattle producers in 2006 documented tropical soda apple as the most common pasture weed across the state of Florida. Over 80% of the survey respondents reported tropical soda apple on their ranches, and over 65% declared the plant to be a major problem for their cattle operation. On ranches that reported tropical soda apple infestations, the level of pastures infested with this weed ranged from a low of 4% in north Florida to a high of 12% in central Florida. The cattle producers' most common strategies to tropical soda apple were herbicide application and mowing. These strategies were used by 32% of respondents in north Florida, 75% in central Florida, and 76% in south Florida. On a statewide basis, 20% of cattle producers used herbicides alone, 7% used mowing alone, and 20% used both methods. Some cattle producers reduced the cattle stocking rate as a consequence of tropical soda apple infestations. This negative impact was reported by only 2% of cattle producers in north Florida, 6% in central Florida, and 7% in south Florida. With the use of the economic input/output model IMPLAN, tropical soda apple control costs resulted in economic losses throughout Florida of $15 million annually in 2006 to cattle producers and their supporting business sectors.

Indigenous and Exotic Dung Beetles (Coleoptera: Scarabaeidae and Geotrupidae) Collected in Florida Cattle Pastures

AbstractDung beetles are important to healthy cattle pasture ecosystems as they provide for nutrient recycling, removal of waste products from the soil surface and assist in the reduction of pestiferous flies. Numerous exotic dung beetles have been accidentally or intentionally introduced to the North American continent and several of these have become established. We surveyed for the presence and distribution of dung beetles on four cattle farms in north central Florida over a 3.5-yr period using cattle dung-baited pitfall traps placed at least every 3 wk. In total, 39 species from 20 genera were identified with a total of 62,320 beetles collected in traps. Although none were intentionally released in Florida, six exotic species were present. Significant differences were observed in species captures among the three most sampled farms, with beetle species dominance patterns differing among the farms. The native species, Onthophagus tuberculifrons Harold, was the most commonly collected species, and both it and the introduced Labarrus pseudolividus Balthasar, had mass emergences. Four of the six most commonly collected species were exotics and included, in order of abundance, L pseudolividus, O. gazella (F.), O. taurus (Schreber), and Euoniticellus intermedius (Reiche).

Florida Cattle Ranching: Five Centuries of Tradition

Florida Cattle Ranching: Five Centuries of Tradition

Land‐use and isolation interact to affect wetland plant assemblages

Different management regimes imposed on similar habitat types provide opportunities to investigate mechanisms driving community assembly and changes in species composition. We investigated the effect of pasture management on vegetation composition in wetlands with varying spatial isolation on a Florida cattle ranch. We hypothesized that increased pasture management intensity would dampen the expected negative effect of wetland isolation on native species richness due to a change from dispersal‐driven community assembly to niche‐driven assembly by accentuated environmental tolerance. We used native plant richness, exotic plant richness and mean coefficient of conservatism (CC) to assess wetland plant assemblage composition. Sixty wetlands were sampled, stratified by three levels of isolation across two pasture management intensities; semi‐native (less intensely managed; mostly native grasses, never fertilized) and agronomically improved (intensely managed, planted with exotic grasses, and fertilized). Improved pasture wetlands had lower native richness and CC scores, and greater total soil phosphorus and exotic species coverage compared to semi‐native pasture wetlands. Increased wetland isolation was significantly associated with decreases in native species richness in semi‐native pasture wetlands but not in improved pasture wetlands. Additionally, the species–area relationship was stronger in wetlands in improved pastures than semi‐native pastures. Our results indicate that a) native species switch from dispersal‐based community assembly in semi‐native pastures to a species‐sorting process in improved pastures, and b) recently‐introduced exotic species already sorted for more intensive management conditions are primarily undergoing dispersal‐based community assembly. That land‐use may alter the relative importance of assembly processes and that different processes drive native and exotic richness has implications for both ecosystem management and restoration planning.

Management of External Parasites with Forced-Use Dust Bags

Revised! ENY-281, a 7-page illustrated fact sheet by P. E. Kaufman, P. G. Koehler, and J. F. Butler, describes this safe, economical, and effective technique for managing external parasites on cattle in Florida — background, directions for hanging commercial dust bags, safety, cost of treatment, and effectiveness. Includes references. Published by the UF Department of Entomology and Nematology, April 2009. ENY-281/IG135: Forced-Use Dust Bags for Management of External Parasites (ufl.edu)

External Parasites of Dairy Cattle

Revised! ENY-251, a 23-page fact sheet by P. E. Kaufman, P. G. Koehler, and J. F. Butler, describes the biology and management of the most important external parasites of dairy cattle in Florida. Includes references and tables of pesticide information. Published by the UF Department of Entomology and Nematology, May 2009. ENY-251/IG050: External Parasites of Dairy Cattle (ufl.edu)

Essential Trace Minerals for Grazing Cattle in Florida

Revised! AN086, an 8-page fact sheet by John D. Arthington, reviews trace minerals that are recognized as deficient in Florida grazing cattle and that are important considerations in supplementation programs, supplementation, and analysis of herd trace mineral status. Published by the UF Department of Animal Science, May 2008.

Liver Fluke Control in Beef Cattle

Revised! VM-120, a 5-page illustrated fact sheet by M.B. Irsik, Charles Courtney III, and Ed Richey, describes the control of Fasciola hepatica, one of the most damaging parasites in Florida cattle — its life cycle, damage to the animal and industry, life cycle of the intermediate host, diagnosis of liver fluke infection, and control of the liver fluke. Published by the UF College of Veterinary Medicine Large Animal Clinical Sciences Department, July 2007.

Genetic Resistance to Johne's Disease in Four Cattle Breeds

Paratuberculosis is a chronic debilitating, infectious disease of ruminants, caused by Mycobacterium avium subsp. paratuberculosis, and characterized by progressive weight loss and profuse diarrhea. The disease has been suspected to have a genetic component and estimations of heritability of 0.15 have been reported. Crohn's disease (CD) is an inflammatory bowel disease in humans resembling many aspects of paratuberculosis. Susceptibility to CD has a strong genetic component and one gene involved has been identified as CARD15 (Caspase recruitment domain 15), with a role in the intracellular recognition of bacterial cell walls as a part of the immune response. The association between mutations in this gene and increased risk of CD has been extensively described. Since Johne's disease has been demonstrated to have a genetic component and genetic variation for infection resistance exists in cattle, CARD15 could also determine differences in resistance to paratuberculosis in the bovine. This candidate gene study focused on determining the alleles present in the CARD15 gene in a population of infected and of noninfected cows. Our objective was characterizing the distribution of two polymorphisms in this gene and testing their association with paratuberculosis infection in Florida cattle with the aim of finding resistance alleles useful in livestock selection.

Florida Carpon Desmodium

Florida carpon desmodium (Figure 1), Desmodium heterocarpon, is among the few perennial summer-growing, grazing-tolerant, herbaceous pasture legumes available to Florida cattle producers. This document is SS-AGR-112, one of a series of the Agronomy Department, UF/IFAS Extension. Original EDIS publication date February 2006. SS-AGR-112/AG249: Florida Carpon Desmodium (ufl.edu)

Vulture-Cattle Interactions A Survey of Florida Ranchers

Effective management of vertebrate pest populations is enhanced by greater understanding of stakeholder-pest interactions as well as stakeholder attitudes toward control of the problem species. It has long been reported that black vultures are responsible for depredation of livestock, especially newborns. To gain a better understanding of this phenomenon, we conducted a survey of 374 Florida cattle ranchers, representing roughly 2% of the total number of Florida cattle ranches. A 3-page questionnaire was used to gather information of ranch characteristics and whether or not the ranchers had experienced vulture attacks. In cases where vulture attacks were reported, respondents were asked to quantify the value of property lost to vultures and preventative measures taken to reduce vulture predation. All respondents were asked a similar set of questions regarding coyotes as well as a series of questions concerning their attitudes toward vulture control and regulations. The survey revealed that 38% of respondents had experienced vulture predation that, on average, resulted in over $2,000 damage. Important predictors of vulture predation were ranch size and number of cattle. Attacks were recorded throughout the year, with the greatest number occurring during the winter months. By gaining better knowledge of stakeholder views and opinions, as well as the extent and characteristics of their depredation problems, we can more efficiently address the needs of livestock ranchers to reduce vulture damage.

Johne's Disease

Mycobacterium avium subspecies paratuberculosis (MAP) is an acid fast intracellular bacillus that infects ruminants worldwide. The disease is characterized by chronic diarrhea and weight loss, despite a good appetite, even on a high plane of nutrition. The disease has a significant economic impact on both the dairy and beef cattle industry in the USA. Control of the disease is difficult due to fecal shedding of the sub-clinical animal and much effort has been put into identifying the disease in the early stages. Currently there are no reliable tests for detecting early infection. The ELISA test has been used in many seroprevalence studies. This method offers the advantage of availability of results in a short period of time and comparable sensitivity to the fecal culture. Sensitivity of the test is approximately 40-50%, but may vary from 15-87% depending on the animal's stage of the infection. Higher sensitivities are obtained from heavy shedders of the bacteria. The specificity of the current ELISA test is 99%. In 1990 Braun et al reported ELISA results of a 1986-1987 survey of Florida cattle indicating a prevalence of 8.6% in beef cattle and 17.1 % in dairy cattle. The high prevalence in that study warranted the re-evaluation of the prevalence of Johne's disease in the state. The objective of this study was to estimate the apparent prevalence of MAP antibodies in Florida cattle from samples submitted to the Florida State Veterinary Diagnostic Laboratory.

Johne's disease

The objective of this study was to estimate the prevalence of M. avium subsp. paratuberculosis infection among beef and dairy cattle in Florida, USA. This was a retrospective seroprevalence study on serum samples from 32?011 cattle originating from 75 herds. Selection was limited to whole herds being tested for diagnostic purposes by owners considering participation in the voluntary Johne's Control Programme or the voluntary Florida Johne's Disease Herd Status Programme. Data were obtained from the Florida State Veterinary Diagnostic Laboratory and USDA-APHIS statewide submission of specimens for Johne's testing from 1999 to 2001. Specimens were evaluated using a commercial IDEXX ELISA kit with a published sensitivity and specificity of 50 and 99%, respectively. Overall prevalence in the sample population was 6.5%; prevalence in beef and dairy cattle was 7.4 and 6.3%, respectively. 83% of herds included in the study had one or more positive cows in the herd. Larger herds (&gt;100 head) had statistically higher herd prevalence than herds with less than 100 cattle. The true prevalence estimate was calculated to be 11.2%. Although within-herd prevalence was lower than previously reported in Florida, seroprevalence appears to be widely distributed and pervasive among Florida cattle. Our findings suggest there could be 168?000 or more cattle in Florida infected with the organism. There is a need for increased awareness of the disease and implementation of control methods appropriate for each individual herd.