Range Education in the 21st Century: Striking the Balance to Maintain a Relevant Profession

Range science education programs strive to keep pace with the changing needs of the range profession and to ensure that range graduates are knowledgeable, skilled, and able to address contemporary, complex problems unique to rangelands. Today, range education programs face many challenges in our ability to meet the demands and needs of our profession and society. First, our capacity to meet the demands for range science graduates has been diminished by 1) elimination or restructuring of academic rangeland science programs, 2) reduced numbers of range-trained faculty teaching rangeland courses, and 3) limited public awareness of degrees and careers in rangeland science and management. Second, range education programs are challenged to strike a balance between retaining traditional basics and modernizing curriculum to include contemporary concepts and technologies. Third, range science graduates need to understand the current social, political, and economic context of resource management, including global change issues that are of paramount concern to society. We propose multiple approaches to meet these challenges: 1) perform needs assessments with diverse stakeholders to ensure that range education programs are relevant to society's needs and address the future of the profession; 2) find innovative approaches to strike the educational balance between fundamental concepts, practical field experiences, and mastery of technical and interpersonal skills; 3) collaborate across institutional boundaries to share educational resources and incorporate course formats that meet the diverse needs of today's students; 4) examine and align professional qualifications, educational standards, and curriculum by defining learning outcomes and core competencies needed by well-trained range professionals; and 5) communicate the unique features of the rangeland profession that solidify its position among the disciplinary pillars of natural resource science and management.     

Host-status of sweet potato cultivars to South Africa root-knot nematodes

Globally, most of the crop-related developmental projects collapsed due to the existence of aggressive plant-parasitic nematodes. Intensive South African biofortification efforts using exotic and local sweet potato (Ipomoea batatas) cultivars have hardly considered the inclusion of nematode resistance in plant breeding, despite the withdrawal of most nematicides from agrochemical markets. The objective of this study was to screen 12 selected biofortification sweet potato cultivars for host-status to South Africa tropical root-knot (Meloidogyne species) nematodes. Three exotic orange-fleshed, three local orange-fleshed and six cream-fleshed cultivars were used in three separate experiments of M. javanica and races 2 and 4 of M. incognita. In each experiment, 6000 eggs and second-stage juveniles/plant were used for inoculation, with nematode assessment performed at 56 days after inoculation. All tested biofortification exotic (except for cv. ‘W-119’) and local cultivars were hosts to Meloidogyne species and races, whereas three non-biofortication local cultivars, namely, ‘Bosbok’, ‘Blesbok’ and ‘Mvuvhelo’ were non-hosts. In conclusion, the findings suggested the likelihood of the existence of non-host-status in certain exotic and local sweet potato cultivars for use in plant breeding programmes against South African Meloidogyne species and races.     

Genetic analyses of nematode egg counts in Hereford and crossbred Hereford cattle in the subtropics of New South Wales

A total of 438 calves was produced by 123 sires of Hereford, Simmental, Friesian and Brahman breeds when mated to Hereford cows. Faecal egg counts and larval differentiation of nematode species were undertaken on one or two occasions prior to weaning at 7 to 8 months. Significant breed of sire and sire within breed effects were observed, but heritabilities, repeatabilities and phenotypic correlations were generally low to moderate.     

Recombinant F1-V fusion protein protects black-footed ferrets (Mustela nigripes) against virulent Yersinia pestis infection.

Black-footed ferrets (Mustela nigripes) are highly susceptible to sylvatic plague, caused by the bacterium Yersinia pestis, and this disease has severely hampered efforts to restore ferrets to their historic range. A study was conducted to assess the efficacy of vaccination of black-footed ferrets against plague using a recombinant protein vaccine, designated F1-V, developed by personnel at the U.S. Army Medical Research Institute of Infectious Diseases. Seven postreproductive black-footed ferrets were immunized with the vaccine, followed by two booster immunizations on days 23 and 154; three control black-footed ferrets received a placebo. After the second immunization, antibody titers to both F1 and V antigen were found to be significantly higher in vaccinates than controls. On challenge with 7,800 colony-forming units of virulent plague by s.c. injection, the three control animals died within 3 days, but six of seven vaccinates survived with no ill effects. The seventh vaccinate died on day 8. These results indicate that black-footed ferrets can be immunized against plague induced by the s.c. route, similar to fleabite injection.     

Use of buspirone and enrichment to manage aberrant behavior in an American badger (Taxidea taxus).

A captive adult female American badger (Taxidea taxus) suffered periodic episodes of agitation and self-mutilation over the course of its lifetime. Initially environmental enrichment curtailed the aberrant behavior; however, intensifying clinical signs periodically required the use of diazepam for amelioration of the problem. When diazepam treatment failed to effectively manage a series of escalating behavioral problems, alternative therapy with buspirone, an azaperone anxiolytic, was initiated. The badger was treated with 10 mg buspirone p.o. b.i.d. for over 18 mo, during which time no undesirable behaviors or noticeable side effects were observed.     

Suppurative polyarthritis in striped skunks (Mephitis mephitis) from Cape Cod, Massachusetts: detection of mycoplasma DNA.

Striped skunks (Mephitis mephitis) from Cape Cod, Massachusetts, U.S.A. were necropsied (n=34; 1995-1997) or clinically evaluated (n=25, 2002-2003) to characterize a lameness and polyarthritis, reported by wildlife veterinarians and rehabilitators, and unsuccessfully treated with antibiotics. Overall, 22 affected skunks had one or multiple swollen joints, swollen paws, and subcutaneous abscesses. Purulent exudate was located in joint spaces, in periarticular connective tissue between muscle fascicles and tendons, and between and along flexor and extensor tendons of the paws. Histologic examination revealed suppurative arthritis, with necrosis and erosion of articular cartilage, and suppurative osteomyelitis. Special stains failed to reveal a causative microorganism within affected joints, and routine bacteriologic cultures failed to isolate a pathogen with any significant frequency or consistency. Polymerase chain reaction (PCR) experiments were performed using DNA extracted from archived, formalin-fixed joint samples of 11 affected skunks, and DNA from joints of 7 of 11 affected skunks yielded amplicons with sequences highly similar to sequences of Mycoplasma fermentans within the Mycoplasma bovis cluster, whereas DNA samples from joints of four unaffected skunks were negative by PCR. Skunks from Connecticut, U.S.A. (n=21; 1995-2003) were similarly examined and were found not to have suppurative polyarthritis, suggesting a unique geographic distribution of this condition. Concurrent pathologic conditions in adult skunks from both Cape Cod and Connecticut included verminous pneumonia, gastric nematodiasis, arthropod ectoparasitism, and canine distemper. Amyloidosis was present in skunks with and without suppurative polyarthritis, and the amyloid was immunohistochemically identified as AA-amyloid. This is the first report of suppurative polyarthritis in wild skunks with evidence of a mycoplasmal etiology.     

Chlorophyll content in eucalypt vegetation at the leaf and canopy scales as derived from high resolution spectral data

The physiological status of forest canopy foliage is influenced by a range of factors that affect leaf pigment content and function. Recently, several indices have been developed from remotely sensed data that attempt to provide robust estimates of leaf chlorophyll content. These indices have been developed from either hand-held spectroradiometer spectra or high spectral resolution (or hyperspectral) imagery. We determined if two previously published indices (Datt 1999), which were specifically developed to predict chlorophyll content in eucalypt vegetation by remote sensing at the leaf scale, can be extrapolated accurately to the canopy. We derived the two indices from hand-held spectroradiometer data of eucalypt leaves exhibiting a range of insect damage symptoms. We also derived the indices from spectra obtained from high spectral and spatial resolution Compact Airborne Spectrographic Imager 2 (CASI-2) imagery to determine if reasonable estimates at a scale of < 1 m can be achieved. One of the indices (R 850/R 710 index, where R is reflectance) derived from hand-held spectroradiometer data showed a moderate correlation with relative leaf chlorophyll content (r = 0.59, P < 0.05) for all dominant eucalypt species in the study area. The R (850)/R (710) index derived from CASI-2 imagery yielded slightly lower correlations over the entire data set (r = 0.42, P < 0.05), but correlations for individual species were high (r = 0.77, P < 0.05). A scaling analysis indicated that the R (850)/R (710) index was strongly affected by soil and water cover types when pixels were mixed, but appeared to be invariant to changes in proportions of understory, which may limit its application.     

Transcutaneous ultrasonographic evaluation of gastric distension with fluid in horses

OBJECTIVE: To develop a transcutaneous ultrasonography (TUS) method for measuring the location of the stomach during various levels of fluid distension and evaluate any correlation between gastric fluid distension and stomach position. ANIMALS: 6 adult horses. PROCEDURES: Known volumes of water were administered in 2 trials. In trial 1, the stomach was evaluated prior to and after the administration of 2, 4, and 6 L of water. In trial 2, the stomach was evaluated after administration of 6, 8, 10, and 12 L of water. The TUS was performed at the 7th through 16th left intercostal spaces (ICSs). For each volume of water, an image was captured at the most dorsal point in each ICS where the dorsolateral aspect of the stomach wall was viewed. The distance between this point and a horizontal line drawn on the skin at the level of the elbow joint was measured. The measurements at all ICSs were used to estimate the gastric wall height at ICS 12, which was subsequently evaluated for statistical association with volume administered. RESULTS: Significant correlation between the estimated height of the stomach wall at ICS 12 and the volume of fluid administered was detected. A regression equation to estimate gastric fluid volume when initial values for gastric wall height (cm) at ICS 12 and fluid volume (L) are known was developed. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that use of TUS for gastric fluid volume estimation is a potentially useful technique.