Adipogenic gene expression and fatty acid composition in subcutaneous adipose tissue depots of Angus steers between 9 and 16 months of age

We have demonstrated that among carcass adipose tissue depots, brisket subcutaneous adipose tissue contains the greatest concentration of MUFA and lowest concentration of SFA. Therefore, we hypothesized that brisket subcutaneous adipose tissue depots would exhibit greater adipogenic gene expression over time than other major subcutaneous adipose tissue depots. Four Angus steers, each at 9, 12, 14, and 16 mo of age, were harvested and fresh subcutaneous adipose tissue samples were collected from over the brisket, chuck, rib, loin, sirloin, round, flank, and plate. Relative gene expression for C/EBPβ, PPARγ, carnitine palmitoyltransferase-1 beta (CPT-1β), stearoyl-coenzyme A desaturase (SCD), AMP-activated protein kinase alpha (AMPKα), and G-coupled protein receptor 43 (GPR43) was analyzed by quantitative real-time PCR. Expression of C/EBPβ, PPARγ, and CPT-1β was greatest at 12 to 14 mo of age (all P < 0.0001) and declined to very low abundance by 16 mo of age in all depots. Expression of PPARγ and CPT-1β was greater (P < 0.03) in flank, rib, and sirloin subcutaneous adipose tissues than in brisket and round adipose tissues. The expression of the SCD gene did not differ among the 4 age groups (P = 0.95). The palmitoleic:stearic acid ratio (an estimate of SCD activity) was greater (P < 0.001) in the subcutaneous adipose tissues from brisket, plate, and round than in the loin, rib, and sirloin. Conversely, subcutaneous adipose tissue from the loin, rib, and sirloin had greater (P < 0.001) SCD gene expression than the brisket, plate, and round. In general, subcutaneous adipose tissues with the highest concentration of MUFA and least SFA consistently exhibited the least SCD gene expression and adipogenic gene expression. We conclude that MUFA in the brisket and other depots with large SCD indices were deposited before 9 mo of age, during a time when the subcutaneous adipocytes were highly differentiated.     

Molecular epidemiological analysis of bat rabies viruses in Brazil

A molecular epidemiological analysis was performed in 19 rabies viruses (RVs) isolated from haematophagous, frugivorous and insectivorous bats, in Sao Paulo, Brazil. The authors carried out RT-PCR for amplification of the RV nucleoprotein (N) gene, and determined 1,335 nucleotide sequences of N gene by direct sequencing method. Phylogenetic analysis, which was based on the N gene of Brazilian RV isolates identified presently and previously, revealed that RVs isolated from bats were genetically divided into four lineages had a tendency to depend on the host bat species. The first lineage consisted mainly of haematophagous bat (Desmodus rotundus) isolates, including frugivorous bat (Artibeus spp.) isolates. Other three lineages consisted of insectivorous bat isolates; mainly Eptesicus spp., Molossus spp. and Nyctinomops spp. isolates, respectively. These results indicate a possibility of that there are bat species-specific RV variants in Brazil.     

大豆花叶病的流行因素及综合防治

1985年设置流行观察圃,以4个品种、4种播期、两种种子传毒率的种子,系统观察各因素对病害流行的作用。另设综合防治田,品种与观察圃相同;采取隔离种植、种传率低、适期播种及早期拔除病苗等措施。1986年用相同的4个品种,设5个隔离试区,各播种不同种传率(0—33％)的种子,测定播种种子传毒率对流行的影响。结果证明:传毒种子是当地最主要的侵染来源,田间杂草不传病,蚜虫传播距离多在100米以内,花期以后被侵染的植株,其种传率显著降低。播种种子传毒率与田间流行程度及收获种子传毒率相关显著。所用防病措施效果明显,可控制田间病情指数为4％、种传率为0％、种子斑驳率低于4％。     

PCR-based specific and sensitive detection of Pectobacterium carotovorum ssp. carotovorum by primers generated from a URP-PCR fingerprinting-derived polymorphic band

A 24-mer primer pair was generated by sequencing a URP-PCR fingerprinting-derived polymorphic band that is uniquely shared in Pectobacterium carotovorum ssp . carotovorum strains (Pcc). The primer set (EXPCCF/EXPCCR) amplified a single band of expected size (0·55 kb) from genomic DNA obtained from 29 Pcc strains and three Pectobacterium carotovorum ssp. wasabiae (Pcw) strains, but not from other P. carotovorum subspecies atrosepticum , betavasculorum or odoriferum , or from other Erwinia spp. or bacterial genera. The Rsa I digestion profile of the amplified bands divided Pcc strains into five groups with a unique profile from Pcw strains. First-round PCR detected between 5 × 10² and 1 × 10³ colony forming units (CFU) mL⁻¹ and detection sensitivity was increased to as few as 2–4 CFU mL⁻¹ after second-round (nested) PCR. This PCR protocol was used directly to detect Pcc strains in infected plant tissues.     

不同光质对嫁接砧木下胚轴生长的影响

近年随着蔬菜生产规模化、工厂化发展的不断扩大和蔬菜嫁接技术的广泛推广,研制蔬菜自动嫁接机已成为蔬菜工厂化生产发展的必然趋势.而要实现嫁接装备高效、精准完成蔬菜幼苗的自动化嫁接作业,首先必须克服蔬菜幼苗生长的不一致性,因此培育健壮、整齐、均匀一致的嫁接蔬菜用苗也是实现自动化嫁接作业的一个重要前提.蔬菜幼苗的生长发育是一个十分复杂的过程,而光源是影响植物生长的一个重要因素.为此,对不同光源(红、蓝、红蓝)照射对3种瓜科砧木幼苗下胚轴生长的影响进行了研究.研究结果表明,红光处理的幼苗下胚轴最高,茎较细;红蓝光处理的砧木幼苗下胚轴最高,茎较粗.对于嫁接砧木幼苗,红光处理具有光合活性,有利于砧木幼苗积累的能量,促进幼苗下胚轴的生长.     

Optimization of a spawning‑induction protocol for the prediction of natural coral spawning

Fisheries Science - Many scleractinian corals only spawn once a year, so opportunities for collecting their gametes are limited. Consequently, the induction of spawning in coral would be useful,...     

Extracellular signal-regulated kinase (ERK) activation in chicken heterophils stimulated with phorbol 12-myristate 13-acetate (PMA), Formyl-methionylleucyl-phenylalanine (fMLP) and lipopolysaccharide (LPS)

The signaling pathways leading to the activation of extracellular signal-regulated kinase (ERK) by phorbol 12-myristate 13-acetate (PMA), formyl-methionylleucyl-phenylalanine (fMLP) and lipopolysaccharide (LPS) in chicken heterophils were examined. To determine the mechanism of ERK's activation and its relation with the influx of calcium ions, heterophils were stimulated by PMA, fMLP and LPS. ERK was not activated by fMLP. LPS- and PMA-stimulated activation of ERK, based on Western blotting with antibodies against the phosphorylated form of ERK, was attenuated by the pretreatment of cells with the intracellular calcium chelator BAPTA/AM (1,2-bis (o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid) but not with the extracellular calcium chelator EGTA (glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid). Exposure of cells to the protein kinase C (PKC) inhibitor GF109203X inhibited the LPS- and PMA-stimulated phosphorylation of ERK in a concentration-dependent manner. The LPS-stimulated phosphorylation was inhibited by pretreatment with the phospholipase C (PLC) inhibitor U73122 but not the phosphatidylinositol 3-kinase (PI₃K) inhibitor LY294002. These results indicate that the LPS-induced phosphorylation of ERK in the chicken heterophils is mediated by PLC, PKC and intracellular calcium, and the PMA-stimulated phosphorylation is dependent on intracellular calcium ion and PKC.     

Age-related changes in contractions of chicken aorta and ischiadic artery

The characteristics of the contraction of vascular smooth muscle were examined in thoracic aorta and ischiadic artery of chickens aged 3, 6, 10 and 18 weeks. High K⁺ solution induced a sustained contraction in smooth muscle preparations of aorta and ischiadic artery in vitro . The contraction of the ischiadic artery became greater with age, whereas the contraction of the aortic preparation did not. In the ischiadic artery, the magnitude of the contraction divided by the weight of the muscle preparation was constant at all ages studied. However, those in the aortic preparation decreased with age. These results suggest that the changes in the contractile responses of vascular smooth muscle owing to the age of chickens vary widely according to the preparations of blood vessels, and that the functional smooth muscle cells in the thoracic aorta of chicken do not increase with age.     

Effects of an environmental enrichment using a drum can on behavioral, physiological and productive characteristics in fattening beef cattle

To evaluate the effects of environmental enrichment on behavioral, physiological and productive characteristics, 71 Japanese Black × Holstein steers (8 months of age; 299.5 ± 22.6 kg) were allocated to three pens in two repetitive experiments. Pen C (n = 11 and 12) consisted of a feeding alley for grain feed, a trough for dry hay, a water bowl and a resting space as a control pen. Pen D (n = 12 and 12) included a drum can (58 cm diameter × 90 cm height) containing hay. Pen GD (n = 12 and 12) included a drum can that was placed around artificial plastic turf (30 × 120 cm) for grooming. The drum cans were removed after 5 months of installation. Behavioral observations were made for 2 h at 10 min intervals after feeding on three successive days each month for 10 months. Agonistic interactions were also continuously observed for 1 h after feeding to assess the dominance order (DO). Sampling blood and measuring bodyweight were performed bimonthly. The steers used the drum can frequently for 3 months after installation (1st, 2nd, 3rd months vs 4 months, all P < 0.05). The frequency of total eating of grain feed and hay was higher in pen D and pen GD than in pen C (both P < 0.01), while it was lowest in pen GD after removal of the drum can (P < 0.05). Grooming at the drum can was observed more frequently in pen GD than in pen D (P < 0.05). After they finished eating the grain feed, they ate hay at the drum can that contained additional hay rather than at the trough for hay (P < 0.01). Plasma dopamine concentrations were higher in pen D than in pen C (P < 0.05), and serum triglyceride concentrations were higher in pen C than in pen GD (P < 0.05) during the installation of the drum can. After removal of the drum can, serum total cholesterol concentrations became higher in pen D and GD than in pen C (both P < 0.05). Average daily gain correlated positively with the frequency of eating hay at the drum can in pen D (r_s = 0.52, P < 0.01). In pen GD, the frequency of using the drum can correlated negatively with DO (r_s = ?0.59, P < 0.01). Carcass belly fat was thicker in pens D and GD than in pen C (both P < 0.01). In pen GD, the frequency of eating hay (r_s = 0.79, P < 0.01) and grooming at the drum can (r_s = 0.63, P < 0.05) correlated positively with the marbling score. Although social factor affected the steers using the drum can, installing it in the early fattening stage encouraged the steers to eat and groom there and resulted in better carcass characteristics through the prolonged physiological positive effects.