Behaviour: an important diagnostic tool for Lake Malawi cichlids

Historically, the cichlid fishes of Lake Malawi, which probably represent one of the best examples of rapid radiation of vertebrates, have been diagnosed with morphological and genetic data. Many of the populations once thought to be conspecific have been hypothesized to be separate species based on behavioural data. The use of behavioural data, as expressed in mate choice based on colour patterns or bower shapes, has been successfully used to diagnose both rock‐dwelling and sand‐dwelling cichlid species. Additionally, a combination of bower shapes and courtship patterns have been used as synapomorphies to diagnose genera within the Lake Malawi cichlid flock. It is concluded that taxonomists need to include behavioural data with morphological and genetic databases to diagnose species and to determine the phylogenetic relationships within this diverse assemblage of fishes.     

An introduction to species concepts and speciation of fishes

More than 22 different species concepts have been proposed. The concepts in general reflect the philosophical outlook, particular expertise, and the groups on which the authors are working. The full‐length papers in this special issue dedicated to species concepts relative to fishes are based on presentations by the authors at the 2001 annual meeting of the American Society of Ichthyologists and Herpetologists at University Park, Pennsylvania, USA and generated much discussion on the topic of what constitutes a species.     

Paternity testing in an autotetraploid alfalfa breeding polycross

Determining unknown parentage in autotetraploid alfalfa (Medicago sativa L.) (2n = 4x = 32) can improve breeding gains. An exclusion analysis-based paternity testing SAS code, amenable to genotyping errors, is presented for autotetraploid species utilizing co-dominant molecular markers with ambiguous dosage. To demonstrate the paternity testing SAS code, 19 SSR loci were genotyped and analyzed on 1,107 progeny from a commercial, isolated, clonally replicated, 16-parent alfalfa breeding polycross which was pollinated by leafcutter bees (Megachile rotundata F.). Paternal assignment success rate was over 90 %. Among typed progeny, 45 % were the result of self-fertilization. Significant differences were detected between the 15 parents that produced seed and were observed as fathers for (1) total fertilizing pollen contribution (% deviation from expectation), (2) self-fertilization rates (%), and (3) outcrossing fertilizing pollen contribution (% deviation from expectation). Physical within-cage distance between parental plants was correlated with outcrossing fertilizing pollen frequency (negative power function). Parental seed yield was positively correlated with total fertilizing pollen contribution, particularly with self-fertilization rates (42 % self-fertilization and 17 % outcrossing). These correlations suggest that selecting for increased seed yield may result in indirect selection for increased self-fertilization rates. Parental total fertilizing pollen contribution was 62 % determined by outcrossing and 35 % by self-fertilization. This study cautions alfalfa breeders that heretofore unconsidered sources of inbreeding could be present in some breeding materials. This study also provides cost effective and easy to use molecular genetic tools for detecting, managing, and/or selecting against (through breeding) those sources of inbreeding.     

Canine multifocal retinopathy caused by a BEST1 mutation in a Boerboel

A 7‐month‐old male intact Boerboel presented to the Cummings School of Veterinary Medicine at Tufts University for the evaluation of ocular discharge. Bilateral multifocal serous retinal detachments were noted on fundus examination as an incidental finding. Genetic testing confirmed the dog to be homozygous for a mutation in the BEST1 gene, where a C₇₃T/R₂₅X change results in premature termination codon. Further testing, including electroretinography and optical coherence tomography (OCT), demonstrated that there was no evidence of retinal photoreceptor dysfunction and confirmed that observed lesions were characteristic of canine multifocal retinopathy. No progression of the lesions was noted 3 months after the initial examination. To the authors’ knowledge, this is the first report of canine multifocal retinopathy in the Boerboel breed.     

Diversity in mind: Towards a differentiated understanding of migrants’ recreational practices in urban forests

This paper presents results of a study investigating the relationship between migration and recreation in urban forests in two German cities. Research in this field is growing in Europe, yet in certain countries, such as Germany, it remains underdeveloped. Until now, it has revealed ambiguities and diverging results. Furthermore, it has been the subject of criticism and calls for more differentiation between and within migrant groups, as well as for more reflection on the categorisation of “migrant” or “ethnic group”. This paper builds on these claims and aims to shed new light on forest recreation and ethnicity through a context-sensitive research approach in the tradition of symbolic interactionism. It draws upon the analysis of 42 qualitative interviews conducted with people with a Turkish, Russian-German and no migration background. The analysis leads to the construction of five narratives, each of them regrouping respondents who share a similar perspective on a specific theme. The narratives show how personal life context and its interlinkages with migration influence the individual's perspectives on and uses of urban forest. They also show how lifestyle and gender shape recreational practices independently from migration background. Beyond the focus on individual experience, collective recreational practices attributed to some groups are expressed in the narratives. This paper addresses the social aspect of leisure and discusses how forest recreation affects the social construction of groups such as migrant groups.     

Effect of Dietary Minerals and Pigment on Somatic Growth of Juvenile Green Sea Urchins, Strongylocentrotus droebachiensis

This study investigated the effects of dietary minerals and pigments in prepared diets on the somatic growth performance of wild and hatchery‐reared juvenile green sea urchins, Strongylocentrotus droebachiensis, by two feeding trials. In the first feeding trial, a modified Bernhart‐Tomerelli salt mix (BT) at 0, 1.5, 3, 6, and 15% dry mass and a Shur‐Gain/Maple Leaf Foods mineral mix at 3 and 6% dry mass were used to test for mineral effects. Pigment effects were tested by incorporating 1.25% Algro? to the prepared diets (i.e., 250 mg of beta‐carotene per kilogram of diet). Sea urchins (13–15 mm of initial test diameter [TD]) collected from the wild were fed the prepared diets over 154 d. The sea urchins that were fed the pigmented diets had significantly greater test growth than those fed the nonpigmented diets, and mineral concentration in the pigmented diets was directly related to juvenile size at the end of the feeding trial. A sample of juveniles from each treatment group was sacrificed to determine test, gonad, and gut yields and ash concentrations. Ash concentrations in the test and gonad were higher for juveniles fed pigmented diets than for those fed nonpigmented diets with similar mineral concentration, suggesting an interaction between minerals and pigments within the juvenile sea urchins. The second feeding trail used two size cohorts of hatchery‐reared juveniles ranging from 1–2 mm and 2–3 mm of initial TD to compare the growth of sea urchins fed either the pigmented diet with 15% BT (i.e., the best diet in the first feeding trial) or kelp, Laminaria longicruris, over 159 d. Growth performance was similar for both cohorts, indicating no size effect, but the juveniles fed the prepared diet were significantly larger at the end of the feeding trial than those fed kelp. This suggests that prepared diets with pigment and high mineral concentration can outperform kelp, and be utilized for juvenile green sea urchins to increase test growth.     

Surgical management of an aberrant left subclavian artery originating from a left patent ductus arteriosus in a dog with a right aortic arch and abnormal branching

An increase in the availability of advanced imaging modalities has led to improved recognition of cardiovascular anomalies. Computed tomography angiography (CTA) provides a non-invasive means of acquiring 3D images with a relatively short acquisition time thereby providing essential information in regards to patient anatomy and procedure planning. The dog in this report had a right aortic arch and abnormal branching with an aberrant left subclavian artery originating from the ampulla of a left patent ductus arteriosus (PDA) that was detected with CTA. The PDA was creating a volume overload to the left side of the heart as well as contributing to the vascular ring and compression of the esophagus. Therefore, ligation and transection instead of a minimally invasive catheter-based procedure was required. This aortic arch anomaly and surgical management have not been previously reported in dogs.     

深圳湾水域微藻的分离及分子生物学鉴定

微藻应用广泛,微藻生物燃料是近年研究热点.深圳的地理和气候条件都非常适宜微藻的生长,具有丰富的微藻资源.从深圳湾水域3个不同位置分别采集了表层和深层(5 m)的水样,利用Soil extrat培养基和Kuhl培养基对水样中的微藻进行分离.将分离得到的菌株扩大培养后提取其基因组DNA,经聚合酶链式反应(PCR)放大18S rRNA,利用内切酶st Ⅰ和TaqⅠ对PCR产物进行双酶切反应以筛选不同的菌株.将不同菌株的PCR产物测序后通过与美国国家生物技术信息中心数据库比对,确定微藻品种.共得到微藻菌株71个,分属于16个不同的属,利用MEGA 5软件建立了系统发育树.同时,初步建立了深圳本地微藻种质资源库.     

Evaluation of sow thermal preference across three stages of reproduction

The metabolic heat production of modern pigs has increased by an average of 16%, compared with sows of 30 years ago. Therefore, it is likely that temperature recommendations require updating to meet the needs of modern pigs. The objective of this study was to evaluate whether different reproductive stages of sows altered thermal preference and if current recommendations required updating. Twenty multiparous sows (3.4 ± 1.2 parity) in different reproductive stages (nonpregnant: n = 7; mid-gestation: 58.5 ± 5.68 d, n = 6; and late-gestation: 104.7 ± 2.8 d, n = 7) were tested. Thermal preference was individually tested, and sows could freely choose a temperature, using a thermal gradient between 10.4 and 30.5 °C. Sows were given 24 h to acclimate to the thermal apparatus. Before testing began, sows were given daily feed allotment and returned to the apparatus. Video from the 24-h test period was used to record sow behavior (time spent inactive), posture (upright and sternal and lateral lying), and location using instantaneous scan samples every 15 min. Data were analyzed using PROC MIXED procedure in SAS 9.4. A cubic regression model was used to calculate the sow’s most preferred temperature based on the location, or temperature, in which they spent the most time. The preference range was calculated using peak temperature preference ±SE for each sow. The reproductive stage altered where sows spent their time within the thermal gradient (P < 0.01). Late-gestation sows preferred cooler temperatures (14.0 °C) than mid-gestation (14.8 °C; P < 0.01) and nonpregnant sows (14.8 °C; P < 0.01). In summary, sow thermal preferences were within the lower half of the current recommended range (10 to 25 °C). This indicates that temperatures at the higher end of the recommended range could be uncomfortable to sows and that the thermal comfort zone of sows may be narrower than recommendations indicate.     

Hypomagnesemia in hospitalized horses

This study was initiated to identify the signalment and clinical variables potentially associated with hypomagnesemia in horses evaluated at the North Carolina State University, College of Veterinary Medicine (NCSU-CVM) veterinary teaching hospital between January 1999 and May 2001. A nested case reference study (nested case-control study) was conducted to examine the potential relationship between hypomagnesemia and signalment, serum chemistry panel analyses, number of hospitalization days, discharge status, and diagnosis. A series of independent and multivariable logistic regression models were used to assess the potential association of each variable with low total serum magnesium concentrations. Four hundred one of 823 (48.7%) horses had serum total magnesium concentrations below the normal reference range. Hypomagnesemia was more likely to occur in horses older than I month of age. Colic (odds ratio [OR]: 2.96, 95% confidence intervals [CI]: 2.14-4.08), acute diarrhea (OR: 5.91, 95% CI: 2.32-15.06), other gastrointestinal disease (OR: 2.07, 95% CI: 1.15-3.71), infectious respiratory disease (OR: 5.07, 95% CI: 2.09-12.28), and multiorgan system disease (OR: 2.31, 95% CI: 1.24-4.28) were associated with hypomagnesemia in adult horses, whereas foals with diarrhea (excluding septic foals) (OR: 0.11, 95% CI: 0.01-0.84) were less likely to have hypomagnesemia. Overall, there was no relationship between hypomagnesemia and mortality (OR: 1.00, 95% CI: 0.72-1.41), but horses with colic and hypomagnesemia were less likely to die than horses with colic and normal or high total magnesium (OR: 0.53, 95% CI: 0.30-0.95). Among horses that survived, hypomagnesemia at admission was associated with a longer hospitalization period (OR: 1.45, 95% CI: 1.00-2.11).