Replacing Soybean Meal with Alternative Protein Sources in Diets for Pond‐raised Hybrid Catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus

The present study investigated the replacement of soybean meal with combinations of two or three alternative protein sources in diets for pond‐raised hybrid catfish, ♀ Ictalurus punctatus × ♂ Ictalurus furcatus. Alternative protein sources evaluated included cottonseed meal, distillers dried grains with solubles (DDGS), peanut meal, and porcine meat and bone meal (PMBM). Hybrid catfish fingerlings with a mean initial weight of 35 g/fish were stocked into 25 earthen ponds (0.04 ha) at a density of 14,826 fish/ha. Fish were fed once daily to apparent satiation for 166 d. No significant differences were observed for total diet fed, net yield, weight gain, survival, carcass yield, fillet yield, or fillet proximate composition among dietary treatments. Results show soybean meal may be completely replaced by combinations of cottonseed meal and one or two other alternative protein sources including DDGS, peanut meal, and PMBM in the diet without markedly affecting production and processing characteristics and fillet proximate composition of pond‐raised hybrid catfish. These alternative diets may be used during foodfish production when prices are favorable.     

Development of colchicine‐induced tetraploid St. Augustinegrass (Stenotaphrum secundatum) lines

St. Augustinegrass is well suited for lawns and commercial landscapes. While many genotypes are cross‐fertile, all cultivars are propagated vegetatively in sod production. To ensure varietal purity, development of sterile triploid hybrids by crossing tetraploid and diploid genotypes has been successfully used in other warm‐season turfgrasses. Applying this model in St. Augustinegrass would be beneficial to sod producers and turf managers who require purity for certification and uniformity for performance, respectively. This study was conducted to develop colchicine‐induced tetraploid lines of St. Augustinegrass. Seeds of cultivar ‘Raleigh’ were treated with four colchicine concentrations at four exposure times. A non‐treated control was included among the treatments. Seedlings that germinated were screened for genome size changes using flow cytometry. Line DSA 13005 and two progeny lines derived through selfing, DSA 16001 and DSA 16016, were corroborated as tetraploids (2n = 4x = 36) through chromosome counts. These lines will be used in future breeding efforts to attempt development of sterile triploid cultivars of St. Augustinegrass.     

THE EFFECTS OF PATIENT POSITIONING AND SLICE SELECTION ON CANINE ACETABULAR ANGLE ASSESSMENT WITH COMPUTED TOMOGRAPHY

Acetabular angles (AAs) and dorsal acetabular rim angles acquired by computed tomographic (CT) imaging have been used to assess patient response to juvenile pubic symphysiodesis surgery. The purpose of this study was to evaluate the effects of patient positioning and slice selection on these angles, and an attempt was made to devise a repeatable method of measuring these angles that would eliminate positioning effects. We found significant variation in AAs with small differences in pelvic tilt and slice selection. Dorsal acetabular rim angles were not affected. As a result of positioning differences from one CT study to the next, every attempt should be made to standardize pelvic tilt, or eliminate its effect on AAs by standardizing gantry angle in relation to an anatomic landmark that will not change over time. The floor of the sacral vertebral canal may be a reasonable landmark for this purpose and deserves further study.     

A coat protein transgene from a Scottish isolate of potato mop-top virus mediates strong resistance against Scandinavian isolates which have similar coat protein genes

Resistance tests were made on seedlings of transformed lines of Nicotiana benthamiana which contain a transgene encoding the coat protein (CP) gene of a Scottish isolate of potato mop-top virus (PMTV). This transgene has been reported to confer strong resistance to the PMTV isolate from which the transgene sequence was derived and also to a second Scottish isolate. Plants of lines of the transgenic N. benthamiana were as resistant to two Swedish and two Danish PMTV isolates as to a Scottish isolate, and of five lines tested, greater than 93.5% of transgenic plants were immune. The coat protein gene sequences of these four Scandinavian isolates were very similar to those of the two Scottish isolates. The greatest divergence between the isolates was three amino acid changes and there was less than 2% change in CP gene nucleotide sequence. It is concluded that the PMTV CP transgene used in these experiments could confer resistance against isolates from different geographical areas because it is becoming apparent that the CP genes of PMTV isolates are highly conserved.     

Hazard tree liability in the United States: Uncertain risks for owners and professionals

The liability United States (U.S.) tree owners face from hazardous trees on their private properties has and continues to undergo a transformation. The traditional common law legal test focused upon whether a tree owner had acted to create a hazardous condition on the property. The modern trend is towards a test that imposes greater responsibility and greater uncertainty on tree owners and arborists. Abandoning the natural/artificial distinction, the modern test, adopted in half the U.S. jurisdictions, imposes general principles of negligence on tree owners. This paper discusses the U.S. legal context for hazardous trees, particularly the impacts on individual tree owners. It closes by addressing various practical means to minimize the risks associated with the modern legal standards, both for susceptible tree owners, and for professionals assessing the subject property.     

Amphibian oncology.

Spontaneous neoplasia is rare in all three orders of Amphibia.Tumors are documented in most major organ systems, and some have various underlying etiologies, including viral infection, environmental contaminants, and genetic predisposition. Currently,treatment options are limited to removal of the predisposing condition(s), palliative care, surgical excision, and, when necessary,humane euthanasia may be elected. Neoplasia must be distinguished from common infectious, nonneoplastic conditions that can negatively impact population health. This article is a review of the more common types of neoplasia in amphibians, and includes clinically relevant information, such as biologic behavior,anatomy, associated etiologies, major differential diagnoses, and clinical management.     

Endoscopic sex determination and gonadal manipulation in Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi).

Seventeen Gulf of Mexico sturgeons (Acipenser oxyrinchus desotoi) underwent endoscopic sex determination, gonadal biopsy, and various reproductive surgeries as part of a conservation development plan. The fish were anesthetized with tricaine methanesulfonate (MS-222) buffered with sodium bicarbonate and maintained on a recirculating water anesthesia circuit. A 6-mm Ternamian EndoTip Cannula, placed through the ventral midline, midway between pectoral and pelvic fins, permitted the introduction of a 5-mm telescope. Swim bladder aspiration and CO2 insufflation of the coelomic cavity provided excellent observation. Second and third cannulae were placed under direct visual control, lateral and cranial or caudal to the telescope cannula. Sex determination was successfully performed in all fish; however, five of 17 sturgeons (29%) required endoscopic gonadal biopsy to confirm sex. Bilateral ovariectomy or orchidectomy was successfully performed in three males and four females. Unilateral ovariectomy and bilateral ligation of the müllerian ducts using an extracorporeal suturing technique was accomplished in an additional three females. No apparent morbidity was associated with the anesthesia or endoscopic surgery in any fish. The ability to safely perform minimally invasive reproductive surgery in fish may have important management and conservation benefits.