Monitoring distances travelled by horses using GPS tracking collars

Objective The aims of this work were to (1) develop a low-cost equine movement tracking collar based on readily available components, (2) conduct preliminary studies assessing the effects of both paddock size and internal fence design on the movements of domestic horses, with and without foals at foot, and (3) describe distances moved by mares and their foals. Additional monitoring of free-ranging feral horses was conducted to allow preliminary comparisons with the movement of confined domestic horses. Procedures A lightweight global positioning system (GPS) data logger modified from a personal/vehicle tracker and mounted on a collar was used to monitor the movement of domestic horses in a range of paddock sizes and internal fence designs for 6.5-day periods. Results In the paddocks used (0.8–16 ha), groups of domestic horses exhibited a logarithmic response in mean daily distance travelled as a function of increasing paddock size, tending asymptotically towards approximately 7.5 km/day. The distance moved by newborn foals was similar to their dams, with total distance travelled also dependent on paddock size. Without altering available paddock area, paddock design, with the exception of a spiral design, did not significantly affect mean daily distance travelled. Feral horses (17.9 km/day) travelled substantially greater mean daily distances than domestic horses (7.2 km/day in 16-ha paddock), even when allowing for larger paddock size. Conclusions Horses kept in stables or small yards and paddocks are quite sedentary in comparison with their feral relatives. For a given paddock area, most designs did not significantly affect mean daily distance travelled.     

Cardiopulmonary effects of a tiletamine-zolazepam combination in sheep

To assess the effects on heart and lung function, a tiletamine-zolazepam (TZ) anesthetic combination was evaluated in 10 Dorset-type ewes. Ewes were randomly allotted to 2 equal groups. Ewes of groups 1 and 2 were given a single bolus of TZ (12 and 24 mg/kg of body weight, IV, respectively) at time zero. Hemodynamic, pulmonary, and ventilation variables were measured at 15-minute intervals to 120 minutes. Blood gas variables were evaluated at 5-minute intervals for the first 30 minutes, then at 15-minute intervals to 120 minutes. In all sheep, TZ administration induced rapid, smooth induction, with gradual and unremarkable recovery. Anesthesia duration was not significantly different between groups (mean +/- SD, 39 +/- 5 and 40 +/- 14 minutes for groups 1 and 2, respectively). Immediate drug effects included apnea, decreased mean arterial blood pressure, and arterial hypoxemia. Cardiac output was significantly decreased in both groups at all times after drug administration. Significant changes in group-1 ewes included increased pulmonary and systemic vascular resistances and decreased inspired minute ventilation, tidal volume, and respiratory airflow. Significant changes in group-2 ewes included increased systemic vascular resistance and decreased pulmonary arterial pressure, inspired minute ventilation, and respiratory airflow. Both drug dosages induced apneustic breathing patterns and caused significant changes in arterial and venous blood hemoglobin concentrations and PCV. Tiletamine-zolazepam is useful for intermediate-duration anesthesia in sheep.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gastrin antibodies: induction, demonstration, and specificity

Antibodies to the antral hormone gastrin have been induced in the rabbit and detected by passive hemagglutination. Specificity of the antibody, as determined by three methods, is directed to gastrins I and II, gastrin pentapeptide, and gastrin tetrapeptide, as well as to the stage-1 gastrin used for immunization.     

Plant circadian clocks increase photosynthesis, growth, survival, and competitive advantage

Circadian clocks are believed to confer an advantage to plants, but the nature of that advantage has been unknown. We show that a substantial photosynthetic advantage is conferred by correct matching of the circadian clock period with that of the external light-dark cycle. In wild type and in long- and short-circadian period mutants of Arabidopsis thaliana, plants with a clock period matched to the environment contain more chlorophyll, fix more carbon, grow faster, and survive better than plants with circadian periods differing from their environment. This explains why plants gain advantage from circadian control.     

Surgical amputation of a digit and vacuum-assisted-closure (V.A.C.) management in a case of osteomyelitis and wound care in an eastern black rhinoceros (Diceros bicornis michaeli)

A 14-yr-old female eastern black rhinoceros (Diceros bicornis michaeli) presented with progressive suppurative osteomyelitis in her left hind lateral toe. beta-Hemolytic Streptococcus sp. was isolated. The animal was treated with multiple systemic antibiotics, and topical wound cleansing. Repeated debridements and nail trimmings were performed for 5 mo prior to electing amputation. The toe was surgically amputated under general anesthesia between the first and second phalanges. Analgesia was diffused into the wound topically via a catheter and elastomeric pump. The open amputation site was covered with adherent drapes and a negative-pressure wound therapy device provided vacuum-assisted closure (V.A.C.) for 72 hr. Three months later this animal developed a deep dermal ulcer on the lateral aspect of the right hind limb, at the level of the stifle. Methicillin-resistant Staphylococcus aureus was isolated. The wound was managed by initial daily lavage, followed by 1 mo of V.A.C. therapy, with 72 hr between dressing changes. Clinically, this therapy expedited the formation of healthy granulation tissue and overall healing was accelerated. The animal tolerated the machine and bandage changes well via operant conditioning. The use of negative-pressure wound therapy appeared to shorten time to resolution of slow-healing wounds in black rhinoceros.     

A duplex-PCR bioassay to detect a Trichoderma virens biocontrol isolate in non-sterile soil

This paper describes the identification and utilisation of a sequence-characterised amplified region (SCAR) marker specific for the Trichoderma virens biocontrol isolate GV4. The marker was developed from a RAPD-PCR amplification product unique to isolate GV4. When used as a hybridisation probe in Southern blot analysis, it hybridised to the DNA of the species T. virens alone and not to that of other Trichoderma species or closely related genera Gliocladium and Verticillium. The marker also produced a GV4-specific RFLP, distinguishing it from other T. virens isolates when probed to blots with HindII, BamHI or PstI genomic DNA digests. Primers designed from the sequence of the RAPD marker produced a diagnostic amplification product of 346 bp for GV4 alone, distinguishing it from all other test isolates. With the exception of one, test isolates did not produce an amplification product with the SCAR primers. The exception was a single Verticillium psalliotae isolate (ICMP5509) that produced a product of approx. 400 bp that was easily distinguished from the 346 bp product of GV4. The reliability of the SCAR-based diagnostic test was further improved with the introduction of a positive PCR reaction control to each test, achieved by converting the test to a duplex PCR system. Two universal primers flanking the two ITS and the 5.8S region of the ribosomal gene complex were introduced to each reaction to provide a test for PCR reaction inhibitors to eliminate false negatives in the diagnosis. Amplification of this multi-copy genomic region did not reduce diagnostic sensitivity of the single copy SCAR marker. To further increase the sensitivity of detecting GV4 propagules while maintaining a fast sample assessment assay, soil was amended with cornmeal, as a nutrient source, and a mix of antibiotics to favour Trichoderma growth. The soil mix was subsequently incubated for 5 d before total DNA was extracted. Under these conditions, the duplex soil PCR assay detected GV4 down to a concentration of 10 spores g⁻¹ soil in non-sterile agricultural field soil. This study is the first to report the use of a duplex-PCR diagnostic bioassay for a species within the Hypocrea/Trichoderma genus.     

Involvement of dehydroalanine and dehydrobutyrine in the addition of glutathione to nisin

Nisin variants and fragments were reacted with glutathione, and the products of the reactions were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and liquid chromatography/mass spectrometry (LC-MS). Reactions between glutathione and either [Ala5]nisin or [Ala33]nisin resulted in products with two glutathione molecules conjugated to one nisin variant molecule. Only one glutathione molecule was added to [Ala5,Ala33]nisin. Fragmentation of the nisin molecule resulted in nisin 1-12, nisin 1-20, and nisin 1-32 fragments. Each fragment retained two dehydro residues, which subsequently underwent reaction with glutathione. The data indicated that the dehydroalanine residues of nisin are sites of addition for glutathione. Such addition renders the nisin molecule inactive.