Supplementation of Lactobacillus casei reduces the mortality of Bombyx mori larvae challenged by Nosema bombycis

Abstract Objective Pebrine, caused by the microsporidium Nosema bombycis, is one of the severe diseases in Thai polyvoltine strains of the silkworm Bombyx mori. Studies showing the presence of Lactobacillus species in the silkworm gut, where the Nosema parasites enter, suggests that these bacteria may have a protective effect. The aim of this study was to investigate the effect of supplementation of Lactobacillus casei on the survival ratio of silkworm larvae challenged with N. bombycis. Results A group of silkworm larvae of the commercial Thai polyvoltine hybrid strain DokBua was supplemented with L. casei on the second day of the 2nd, 3rd, 4th, and 5th instar. When a control group of silkworm larvae were challenged with N. bombycis on the second day of the 4th instar, the survival rate was 68%, but it was 91% for larvae supplemented with L. casei. For those larvae that survived the treatments until pupation, we determined the growth characters larval weight, cocooning ratio, and pupation ratio, and the economic characters cocoon weight and cocoon shell weight. When infected with N. Bombycis, growth characters were significantly higher in larvae also receiving L. casei.

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Effects of Pyriproxyfen Exposure on Reproduction and Gene Expressions in Silkworm, Bombyx mori

Insects ◽

10.3390/insects11080467 ◽

2020 ◽

Vol 11 (8) ◽

pp. 467

Author(s):

He-Ying Qian ◽

Xiao Zhang ◽

Guo-Dong Zhao ◽

Hui-Min Guo ◽

Gang Li ◽

...

Keyword(s):

Bombyx Mori ◽

Model Organism ◽

Ovary Development ◽

Control Group ◽

Hatching Rate ◽

Hormone Regulation ◽

Concentration Effects ◽

Gene Expressions ◽

Silkworm Larvae ◽

Silkworm Bombyx Mori

The silkworm, Bombyx mori Linnaeus, is an important economic insect and a representative model organism of Lepidoptera, which has been widely used in the study of reproduction and development. The development of the silkworm’s reproductive gland is easily affected by many external factors, such as chemical insecticides. After the silkworm larvae were treated with different concentrations of pyriproxyfen, the results showed that the number of eggs and hatching rate of eggs in the silkworm can be reduced by pyriproxyfen, and the concentration effects were displayed. Pyriproxyfen exposure could affect the normal development of the ovary tissue by reducing the number of oocytes and oogonia in the ovaries of silkworm fed with pyriproxyfen. We employed qRT-PCR, to detect the expressions of genes related to ovary development (Vg, Ovo, Otu, Sxl-S and Sxl-L) and hormone regulation (EcR and JHBP2) in silkworm. Our study showed that the transcription levels of Vg, Ovo, Otu, Sxl-S and Sxl-L in the treatment group were lower than those in the control group (6.08%, 61.99%, 83.51%, 99.31% and 71.95%, respectively). The transcription level of ECR was 70.22% for the control group, while that of JHBP2 was upregulated by 3.92-fold. Changes of transcription levels of these genes caused by pyriproxyfen exposure ultimately affect the absorption of nutrients, energy metabolism, ovary development and egg formation of the silkworm, thus leading to reproductive disorders of the silkworm. In general, our study revealed the response of silkworm reproduction to pyriproxyfen exposure and provided a certain reference value for the metabolism of the silkworm to pyriproxyfen.

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Controlling of bacterial and fungal diseases that contaminating mulberry silkworm, Bombyx mori by using some plant extracts

Bulletin of the National Research Centre ◽

10.1186/s42269-019-0218-3 ◽

2019 ◽

Vol 43 (1) ◽

Author(s):

Mahmoud S. I. Saad ◽

Enas M. Y. Elyamani ◽

Walaa M. M. Helaly

Keyword(s):

Bombyx Mori ◽

Larval Mortality ◽

Pupal Weight ◽

Filament Length ◽

Larval Weight ◽

Shell Weight ◽

Cocoon Production ◽

Black Seed ◽

Mulberry Silkworm ◽

Silk Filament

Abstract Background Mulberry silkworm, Bombyx mori L. is one of the most economically important insect because its production of silk which interfere with many important industries. Diseases of the silkworm, B. mori such as viral, bacterial, fungal and protozoan pathogens seriously affect their cocoon production. Bacterial and fungal pathogens independently cause the highest cocoon loss, so the use of botanicals is considered an important strategy to control diseases of silkworm. Results The artificially infected silkworm, B. mori larvae with Bacillus thuriengiensis when treated with concentrations of 2 and 3% of black seed and basil leaves extracts increased significantly larval weight and decreased larval mortality. In addition, 3% basil leaves extract and 1% of black seed increased pupal weight. Cocoon weight and cocoon shell weight increased significantly by 3% basil leaves extract treatment. All tested concentrations of black seed extract increased the silk ratios of the resulted cocoons as compared to the infected control. For technological parameters, all tested extracts at 3% concentration caused the highest silk filament length; meanwhile control larvae recorded the highest silk filament weight and size. Regarding the mulberry silkworm, B. mori artificially infested with conidial solution of Beauveria bassiana when treated with all concentrations of the tested plants showed an enhancement in larval weight, pupal weight, cocoon weight, cocoon shell weight, silk filament length, and filament weight and reduced the larval mortality percentage. The highest silk filament size were recorded for the control group. Conclusions Tested concentrations of Morus alba, Ocimum basilicum leaves extracts and Nigella sativa seeds extract have suppressed the bacterial and fungal disease spread when used three times through both 4th and 5th larval instars. Moreover, the biological characters and technological traits enhanced by using of these extracts, so it can be used in sericulture for improving cocoon crop quality and quantity.

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Larval growth, silk production and economic traits of Bombyx mori under the influence of honey-enriched mulberry diet

Journal of Applied and Natural Science ◽

10.31018/jans.v7i1.603 ◽

2015 ◽

Vol 7 (1) ◽

pp. 286-292 ◽

Cited By ~ 2

Author(s):

N. Thulasi ◽

S. Sivaprasad

Keyword(s):

Growth Rate ◽

Protein Synthesis ◽

Bombyx Mori ◽

Larval Growth ◽

Silk Gland ◽

Economic Traits ◽

Silkworm Larvae ◽

Shell Weight ◽

Shell Protein ◽

The Impact

The impact of honey on the silkworm, Bombyx mori was demonstrated with reference to the larval growth, silk gland proteins and economic parameters of sericulture. The honey works well at a concentration of 2% in distilled water. At this concentration it promotes growth rates in the silkworm larvae during fifth instar development. It positively reinforces the day-to-day larval growth rate by 4.75 additional percentile points, silk gland growth rate by 4.45 additional percentile points and the gland-body ratio by additional 6.64 percentile points. It stimulates silk protein synthesis in all the three segments of the silk gland, viz., the anterior, middle and posterior parts. Under its influence, the silk gland protein profiles grew significantly by 14.85 additional percentile points in the anterior silk gland (ASG), minimally by 8.68 additional percentile points in the middle silk gland (MSG) and maximally by 15.17 additional percentile points in the posterior silk gland (MSG), compared to their control values. It also stimulates the core shell protein synthesis by 18% and retards floss protein synthesis by ~25% in the three segments of silk gland. In doing so, it contributes to sericulture industry by causing improvements in profit making economic traits such as gland-body ratio, cocoon weight, shell weight, raw silk weight, denier and renditta and by reducing the production of floss, which contributes to loss in the sericulture industry. Honey is suggested as a profitable supplementary diet forsilkworm.

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Effect of Methoprene on larval and cocoon weight, ovariole length, egg number and fecundity of Bombyx mori L

ENTOMOLOGIA HELLENICA ◽

10.12681/eh.13979 ◽

2017 ◽

Vol 8 ◽

pp. 37

Author(s):

S.B. Magadum ◽

Μ.Α. Hooli ◽

V.B. Magdum

Keyword(s):

Bombyx Mori ◽

Larval Weight ◽

Silkworm Larvae ◽

Egg Number ◽

Repeated Applications ◽

Bombyx Mori L

The effect of Methoprene on larval and cocoon weight, ovariole length, egg number and fecundity of BombYx mori (Polyvoltine Pure Mysore breed) was studied. Methoprene at 2.75,4.0 and 8.0 pg!ml dilutions was topically applied/sprayed on silkworm larvae repeatedly at 36h in 3rd, 4th and 5th stadium, at 48h in 4th and 5th stadium and singly at 72h in 5th stadium. Of the various dosages used, the repeated applications of 2.75 pg/ml at 36h in 3rd, 4th and 5th stadium of silkworm larvae resulted in significant increase in larval weight, cocoon weight, ovariole length, ovariole egg number and fecundity when compared to untreated controls.

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Stability and path analysis for yield and related traits in silkworm, (Bombyx mori L.) reared under stress conditions

Genetika ◽

10.2298/gensr1601271c ◽

2016 ◽

Vol 48 (1) ◽

pp. 271-284

Author(s):

N. Chandrakanth ◽

S.M. Moorthy ◽

M. Rekha ◽

V. Sivaprasad

Keyword(s):

Bombyx Mori ◽

High Temperatures ◽

Analysis Of Variance ◽

Path Coefficient ◽

Larval Weight ◽

Stability Parameters ◽

Shell Weight ◽

Pupation Rate ◽

Bombyx Mori L ◽

Silkworm Bombyx Mori

The silkworm, Bombyx mori L. is a poikilothermic organism whose growth and development is adversely affected by high temperatures. Rearing of silkworm at high temperature conditions of tropical countries like India causes extensive crop loss by reducing cocoon yield. Breeding new silkworm breeds tolerant to high temperatures is the most effective and economical method to increase cocoon yield. Introduction of stable genotypes in such breeding programs and knowledge on the relationships between cocoon yield and other traits would be more advantageous in increasing cocoon yield at high temperatures. Therefore, in this study twenty silkworm genotypes were reared in five artificially simulated environments with different temperatures ranging from 25?C to 38?C. Based on coefficient of variation (%) values, the traits cocoon yield / 10,000 larvae by weight (CY) and cocoon weight showed maximum and minimal variation among the traits in all the five environments. Analysis of variance revealed a substantial genetic variability among the genotypes for most of the traits studied. The results of combined analysis of variance showed significant differences over traits indicating that the traits are influenced by genotype ? environment interactions. Stability analysis with respect to CY showed higher mean value compared to grand mean, regression coefficient equal to unity and less deviation from regression in ATR16, CSR17, BHR2, S-5 and D13 genotypes, suggesting that they are consistent with the CY over the different environments. Clustering based on the stability parameters resulted in separation of twenty silkworm genotypes into 5 clusters based on their ability to tolerate high temperatures. Correlation studies demonstrated positive and significant (P < 0.05) correlations between CY and other traits. Pupation rate was most positively associated with CY followed by larval weight, cocoon weight, cocoon shell weight and cocoon shell percent. Path coefficient analysis also revealed that the pupation rate had the maximum direct effect on CY followed by cocoon shell weight and larval weight. Cocoon shell percent and cocoon weight exhibited negative direct path effect on cocoon yield / 10,000 larvae by weight. Therefore, the selection based on pupation rate, larval weight and cocoon shell weight can be effective in improving cocoon yield in silkworm at different environments with varying temperature.

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PSVIII-8 Effect of Lactobacillus Casei Zhang on E. coli induced injury of blood and milk barrier in dairy cow

Journal of Animal Science ◽

10.1093/jas/skaa278.468 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 259-259

Author(s):

Yuhui Zheng ◽

Shengli Li

Keyword(s):

Bacterial Infection ◽

Lactobacillus Casei ◽

Bacterial Resistance ◽

Bovine Mastitis ◽

Production Performance ◽

Economic Losses ◽

Control Group ◽

Bovine Mammary Epithelial Cells ◽

E Coli ◽

Lactobacillus Casei Zhang

Abstract Bovine mastitis is one of the major diseases which directly affects the milk production performance and it causes huge economic losses in the dairy industry. Bacterial infection is the main risk factor of bovine mastitis and the antibiotic therapy is the primary choice to control the disease. However, persistence use of antibiotic increases the incidence of bacterial resistance and traces of antibiotic residues in animal products. Lactobacillus casei Zhang is one of the probiotics with multiple biological functions, which has certain bacteriostatic effect on pathogenic microorganism. The purpose of this study was to explore the effect of Lactobacillus casei Zhang (L. casei Zhang) on the prevention of E. coli-induced milk-blood barrier damage. Bovine mammary epithelial cells (BMECs) were used to establish a milk-blood model and Control group (PBS), E. coli group, and L. casei Zhang pretreatment plus E. coli group were set up respectively. The results showed that: L. casei Zhang could significantly reduce the increase of LDH release caused by E. coli treatment (P< 0.05). And it can also significantly reduce the decrease of transmembrane resistance of monolayer cells caused by E. coli treatment (P< 0.05). In addition, L. casei Zhang could significantly reduce the expression of tight junction proteins ZO-1, Claudin-1, Claudin-4 and Occludin (P < 0.05). In conclusion, L. casei Zhang could effectively improve the damage of the blood-milk barrier caused by E. coli and could protect BMECs during bacterial infection.

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Changes in H+-translocating vacuolar-type ATPase in the anterior silk gland cell of Bombyx mori during metamorphosis.

Journal of Experimental Biology ◽

10.1242/jeb.201.4.479 ◽

1998 ◽

Vol 201 (4) ◽

pp. 479-486

Author(s):

M Azuma ◽

Y Ohta

Keyword(s):

Bombyx Mori ◽

Gland Cell ◽

Specific Inhibitor ◽

Instar Larva ◽

Silk Gland ◽

Ultrastructural Changes ◽

Immunocytochemical Staining ◽

Apical Plasma Membrane ◽

Apical Surface ◽

Silkworm Larvae

A proton-translocating vacuolar-type ATPase (V-ATPase) was identified and characterized in the anterior silk gland of Bombyx mori. By incubating the intact tissue with the fluorescent dye Acridine Orange, the acidified compartment was detected at the apical pole of the epithelial cells. This was observed throughout the feeding period of the fifth-instar larva until the onset of spinning. Acidification was prevented completely and reversibly by 0.8 micromol l-1 bafilomycin A1, a specific inhibitor of V-ATPase. The presence of V-ATPase in a microsomal fraction was verified by immunoblots using an antiserum to the V-ATPase holoenzyme from Manduca sexta midgut. The antiserum localized the V-ATPase to the apical plasma membrane of the anterior silk gland cells, suggesting that the enzyme is functionally active in pumping protons out of the cell towards the glandular lumen of feeding silkworm larvae. In spinning larvae, the acidification produced by the V-ATPase appears to cease, because acidic compartments were seen rarely and only in the periphery of basal cytoplasm, and because immunocytochemical staining for the V-ATPase was greatly reduced at the apical surface. The metamorphic changes in relation to the occurrence of V-ATPase corresponded well with the ultrastructural changes in the anterior silk gland cell of Bombyx mori larvae.

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Effect of Antibiotics on the Haemocyte Count and Rearing Performance of Silkworm Bombyx mori L.

Current Journal of Applied Science and Technology ◽

10.9734/cjast/2020/v39i4831274 ◽

2020 ◽

pp. 528-538

Author(s):

Iqra Rafiq ◽

Z. I. Buhroo ◽

K. A. Sahaf ◽

N. A. Ganie ◽

M. F. Baqual ◽

...

Keyword(s):

Bombyx Mori ◽

Economic Traits ◽

Silkworm Larvae ◽

Mulberry Leaves ◽

Survival Percentage ◽

Bombyx Mori L ◽

Ceftiofur Sodium ◽

Antibiotic Agents ◽

Silkworm Bombyx Mori ◽

Total Haemocyte Count

Background: Antibiotic agents have been used in recent years to increase the growth of silkworm larvae and to improve production. In this context, the present investigation reported the effects of ceftiofur sodium, oxytetracycline and enroflaxcin on total haemocyte count (cells/mm3), survival percentage and economic characteristics in silkworm Bombyx mori L. at various concentration levels. The study regarding the effect of antibiotics was conducted on the silkworm breed APS-45. Three concentrations (0.05%, 0.10% and 0.15%) were prepared for each antibiotic. The worms were reared upto 3rd instar without any treatment. After third moult silkworms were supplemented with antibiotic fortified mulberry leaves. Results: The experimental results showed that the effect of different antibiotics on economic parameters like larval weight, larval duration, cocoon weight, shell ratio and raw silk percentage were significantly increased in the treated lines in comparison to the control. Antibiotics also increased survival percentage and the most effective result was obtained at 0.15% of ceftiofur sodium followed by oxytetracycline and enroflaxcin. In the present study highest THC value of 9157.33 mm/cm3 was recorded in treatment ceftiofur sodium treated batch at concentration C3 0.15%. An increment in the total haemocyte count was observed in other treatments as well and the cell count increased with an increase in concentration of antibiotic dosage and the effectiveness of the antibiotics followed the order ceftiofur sodium, oxytetracycline and enroflaxcin. Conclusion: This research outlines that there is a significant improvement in the total haemocyte count and economic traits in silkworm with the supplementation of antibiotic fortified mulberry leaves. The antibiotic treatment has significantly improved the raw silk percentage and has been found to be effective in reducing the mortality of silkworms. So, this antibiotic fortification can be further exploited for higher raw silk production.

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