The effects of dietary omega fatty acids on pregnancy rate,plasma prostaglandin metabolite levels,serum progesterone levels,and milk fatty-acid profile in beef cows

The objectives were to determine the effects of feeding supplements rich in omega-6 or omega-3 fatty acids (FA) during the late gestation to the early postpartum and breeding periods on reproduction and milk FA profile in beef cows. For each of two years, at the beginning of period 1 (mid-December), 72 beef cows, calving in January or February, were assigned to diets supplemented with roasted flaxseed (Flax) or roasted soybean (Soybean). For each of two years, after 11 wk (end of period 1), 18 cows of 36 in the Flax group were switched to the soybean supplement and 18 cows of 36 in the Soybean group were switched to the flax supplement (start of Period 2). Cows were bred by timed artificial insemination (TAI) in week 5 of period 2. The FA composition of the milk reflected the FA profile of the oilseed supplements. There were no differences in pregnancy rates among the 4 groups. The treatments had no effect on plasma prostaglandin metabolite levels or ratios at 4 to 11 d postpartum. At 5 to 6 d post- TAI, pregnant cows fed Flax in period 1 had lower (P < 0.05) plasma prostaglandin F metabolite (PGFM) levels and PGFM to prostaglandin E metabolite (PGEM) ratio than cows fed Soybean, but there were no significant differences at 19 to 20 d post-TAI. Cows pregnant from TAI and fed Flax in period 2 had higher (P < 0.05) serum progesterone levels at 5 to 6 d post-TAI than cows fed Soybean, but there was no difference at 19 to 20 d post-TAI. The dietary treatments had no effect on pregnancy rates, but there were some effects on plasma PGFM levels, PGFM to PGEM ratios, and serum progesterone levels. The FA supplements influenced the FA composition of milk.     

The performance of larval Seriola lalandi (Valenciennes, 1833) is affected by the taurine content of the Artemia on which they are fed

This study describes the effects of feeding taurine‐supplemented Artemia on the growth, survival, whole body taurine content and jaw malformation rate of larval yellowtail kingfish Seriola lalandi. Larvae were fed rotifers containing no supplemental taurine from 3 to 15 day post hatch (dph) and Artemia co‐enriched with taurine from 12 to 22 dph. Artemia were supplemented at concentrations of either 0, 0.8, 1.6, 2.4, 3.2 or 4.0 g of taurine L^?1 during the 18 h HUFA enrichment process. Taurine content in the Artemia increased from 0.76 ± 0.04% DW in those without supplementation to 3.95 ± 0.17% DW in those supplemented at 4.0 g L^?1. Survival rates of larval yellowtail kingfish were significantly lower in all taurine‐supplemented treatments compared to the unsupplemented control. Growth was significantly improved in those larvae fed taurine‐supplemented Artemia; however, we cannot attribute this improvement solely to taurine, as improved growth may have been a function of the reduced survival, and therefore increased prey availability, in these treatments. The whole body taurine content of larvae fed unsupplemented Artemia was significantly lower (1.85 ± 0.03% DW) than those fed supplemented Artemia, which did not differ from each other (pooled average 2.48 ± 0.03% DW), suggesting either a functional excretion mechanism is in place or that this represents the saturation value for larvae of this age. Jaw malformation rates were not affected by Artemia taurine content. The results of this research suggest yellowtail kingfish larvae may have a lower requirement and/or a reduced tolerance to excess dietary taurine than juveniles.     

Initial Detection and Molecular Characterization of Namaycush Herpesvirus (Salmonid Herpesvirus 5) in Lake Trout

A novel herpesvirus was found by molecular methods in samples of Lake Trout Salvelinus namaycush from Lake Erie, Pennsylvania, and Lake Ontario, Keuka Lake, and Lake Otsego, New York. Based on PCR amplification and partial sequencing of polymerase, terminase, and glycoprotein genes, a number of isolates were identified as a novel virus, which we have named Namaycush herpesvirus (NamHV) salmonid herpesvirus 5 (SalHV5). Phylogenetic analyses of three NamHV genes indicated strong clustering with other members of the genus Salmonivirus, placing these isolates into family Alloherpesviridae. The NamHV isolates were identical in the three partially sequenced genes; however, they varied from other salmonid herpesviruses in nucleotide sequence identity. In all three of the genes sequenced, NamHV shared the highest sequence identity with Atlantic Salmon papillomatosis virus (ASPV; SalHV4) isolated from Atlantic Salmon Salmo salar in northern Europe, including northwestern Russia. These results lead one to believe that NamHV and ASPV have a common ancestor that may have made a relatively recent host jump from Atlantic Salmon to Lake Trout or vice versa. Partial nucleotide sequence comparisons between NamHV and ASPV for the polymerase and glycoprotein genes differ by >5% and >10%, respectively. Additional nucleotide sequence comparisons between NamHV and epizootic epitheliotropic disease virus (EEDV/SalHV3) in the terminase, glycoprotein, and polymerase genes differ by >5%, >20%, and >10%, respectively. Thus, NamHV and EEDV may be occupying discrete ecological niches in Lake Trout. Even though NamHV shared the highest genetic identity with ASPV, each of these viruses has a separate host species, which also implies speciation. Additionally, NamHV has been detected over the last 4 years in four separate water bodies across two states, which suggests that NamHV is a distinct, naturally replicating lineage. This, in combination with a divergence in nucleotide sequence from EEDV, indicates that NamHV is a new species in the genus Salmonivirus.

Received April 20, 2015; accepted October 11, 2015     

ABA和IAA对猕猴桃果实成熟进程的调控

以中华猕猴桃和美味猕猴桃果实为试材,研究果实成熟过程中内源ＡＢＡ,ＩＡＡ和乙烯的变化以及外源ＡＢＡ和ＩＡＡ处理对果实后熟软化进程的调控及其在生理基础。结果表明,果实采后初期,ＡＢＡ含量迅速升高,在２－４ｄ达到最大值,之后快速下降;在ＡＢＡ下降过程中,乙烯进入跃变期,果实后熟进程加快,外源ＡＢＡ处理增加内源ＡＢＡ含量,加快内源ＩＡＡ的降解,促使脂氧合酶活性峰值提前出现,加速果实软化,果实后熟进程中,     

Sexual Transmission of Somatic Embryogenesis in Dactylis glomerate*

A Dactylis glomerata L. genotype that produces somatic embryos in vitro was tested for the ability to sexually transmit the embryogenic trait. Reciprocal crosses were performed between the embryogenic and two non-embryogenic genotypes. Leaf segments from 69 F₁ plants were cultured on Schenk and Hildebrandt medium amended with 30 μM 3,6-dichloro-o-anisic acid (dicamba). Somatic embryogenesis was expressed in 39 of the F₁ plants. The embryogenic parent was female for 18 of these plants and male for the other 21. The 39:30 ratio of embryogenic: non-embryogenic fits an expected 1:1 for tetrasomic inheritance of a dominant nuclear gene.     

Are review articles a reliable source of evidence to support conservation and environmental management? A comparison with medicine

Review articles are important sources of information and often the only source of evidence used by decision makers in conservation and environmental management to assess effectiveness and impact of interventions and other actions. Recent developments in the field of medicine and public health have established ‘systematic review’ guidelines to minimise bias and explicitly document methodology, allowing replication and updating in light of further advances. The aim of this article was to assess the methodological and reporting rigour of reviews from the disciplines of conservation, ecology and environmental management (referred to as “ecological reviews”). This was achieved by comparing them to medical systematic reviews, using 27 detailed criteria well established in medicine. When compared with medical systematic reviews, ecological reviews were more likely to be prone to bias, lacking details in the methods used to search for studies, and were less likely to assess the relevance of studies, quality of the original experiments and to quantitatively synthesise the evidence. Overall, ecological reviews show lower quality and greater variation in reporting style and review methods. To address this, reviewers could use a systematic review approach and journals could provide more explicit guidelines for the preparation and production of review articles.     

Retrospective Review of 50 Canine Intracranial Tumors Evaluated by Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) was performed on 50 dogs with intracranial neoplasia. The following tumor features were assessed: axial origin, location, shape, growth pattern, MRI signal intensity, evidence for edema, and paramagnetic contrast enhancement. Histologic diagnoses included 5 intracranially invading nasal tumors, 7 pituitary tumors, 22 meningiomas, 6 choroid plexus tumors, 7 astrocytomas, 1 ependymoma, and 2 oligodendrogliomas. Axial origin, site, shape, and growth pattern were important diagnostic characteristics for tumor type. Signal intensity and contrast enhancement pattern allowed further differentiation. Characteristic MRI features that facilitate diagnosis and prognosis were identified. Accurate diagnosis of tumor type based on these features was not always possible because of similarities in MRI appearance for some tumors. Tissue biopsy remains necessary for definitive diagnosis of intracranial tumors.