The phases and effects of low temperature exposure on embryonic development in Hermetia illucens (L.) (Diptera: Stratiomyidae)

Research on the black soldier fly (Hermetia illucens (L.) Diptera: Stratiomyidae) is steadily increasing, with a focus on its larvae and applications thereof. The egg stage of this species has received less research. This study describes the phases of embryo development for BSF eggs and the potential of delaying embryo development by using a chilling protocol. The study found that when chilling eggs for 24 hours at 10 °C and 80% relative humidity, the development is paused for a full day. This study presents a window of opportunity for embryo ages, approximately 38-58 hours post oviposition, where the hatch success is the least affected (>80% hatching when compared to control). Outside of this window, the hatch success decreases to 70% and lower. The description of embryo development can be used as a reference tool for quality control purposes. The effect of treatments on eggs can be determined by identifying key processes in development. Furthermore, the chilling of embryos and thus pausing of development can be applied in a production setting.

Vertically transmitted microbiome protects eggs from fungal infection and egg failure

Background Beneficial microbes can be vertically transmitted from mother to offspring in many organisms. In oviparous animals, bacterial transfer to eggs may improve egg success by inhibiting fungal attachment and infection from pathogenic microbes in the nest environment. Vertical transfer of these egg-protective bacteria may be facilitated through behavioral mechanisms such as egg-tending, but many species do not provide parental care. Thus, an important mechanism of vertical transfer may be the passage of the egg through the maternal cloaca during oviposition itself. In this study, we examined how oviposition affects eggshell microbial communities, fungal attachment, hatch success, and offspring phenotype in the striped plateau lizard, Sceloporus virgatus, a species with no post-oviposition parental care. Results Relative to dissected eggs that did not pass through the cloaca, oviposited eggs had more bacteria and fewer fungal hyphae when examined with a scanning electron microscope. Using high throughput Illumina sequencing, we also found a difference in the bacterial communities of eggshells that did and did not pass through the cloaca, and the diversity of eggshell communities tended to correlate with maternal cloacal diversity only for oviposited eggs, and not for dissected eggs, indicating that vertical transmission of microbes is occurring. Further, we found that oviposited eggs had greater hatch success and led to larger offspring than those that were dissected. Conclusions Overall, our results indicate that female S. virgatus lizards transfer beneficial microbes from their cloaca onto their eggs during oviposition, and that these microbes reduce fungal colonization and infection of eggs during incubation and increase female fitness. Cloacal transfer of egg-protective bacteria may be common among oviparous species, and may be especially advantageous to species that lack parental care.

Loss of spawning habitat and prerecruits of Pacific cod during a Gulf of Alaska heatwave

Pacific cod (Gadus macrocephalus) stocks in the Gulf of Alaska experienced steep, unexpected declines following an unprecedented 3-year marine heatwave (i.e., “warm blob”) from 2014 to 2016. We contend that stock reproductive potential was reduced during this period, evidenced by a combination of new laboratory data demonstrating narrow thermal hatch success (3–6 °C), mechanistic-based models of spawning habitat, and correlations with prerecruit time series. With the exception of single-year El Niño events (1998, 2003), the recent 3-year heatwave (2014–2016) and return to similar conditions in 2019 were potentially the most negative impacts on spawning habitat for Pacific cod in the available time series (1994–2019). Continued warming will likely reduce the duration and spatial extent of Pacific cod spawning in the Gulf of Alaska.

Perancangan Dan Pembuatan Mesin Tetas Telur Burung Puyuh Berbasis Mikrokontroler

Tujuan dari perancangan dan pembuatan alat ini adalah untuk menghasilkan software dan alat tetas telur burung puyuh otomatis dengan menggunakan arduino uno sebagai mikrokontroler. Arduino uno akan mengatur seluruh kerja sistem alat tetas telur sesuai dengan program yang diberikan. Pembuatan alat ini menggunakan metode rak geser untuk memutar telur secara otomatis. Dengan metode rak geser ini motor akan bergerak setiap 3 jam sekali selama 3 detik menggeser rak sehingga telur akan berputar. Hasil pembuatan alat ini adalah terciptanya sebuat alat tetas telur burung puyuh otomatis berbasis mikrokontroler. Setelah melakukan percobaan menetaskan telur burung puyuh alat ini memperoleh keberhasilan penetasan sebesar 85 %. Berdasarkan hasil percobaan dapat dinyatakan bahwa sistem penetasan telur burung puyuh menggunakan alat ini bekerja dengan baik dan bisa diimplementasikan sebagaimana tujuan pembuatan alat ini.Kata kunci : Arduino Uno, DHT 11, Passive Infra Red (PIR), dimmer. The purpose of the design and manufacture of this tool is to produce automatic quail egg software and hatching tools using Arduino Uno as a microcontroller. Arduino Uno will manage the entire work of the hatchery system in accordance with the given program. Making this tool uses a sliding rack method to rotate eggs automatically. With this sliding rack method the motor will move every 3 hours for 3 seconds to move the rack so the eggs will spin. The result of making this tool is the creation of a microcontroller-based automatic quail egg hatching tool. After conducting experiments, hatching quail eggs, this tool gained 85% hatch success. Based on the results of experiments it can be stated that the quail egg hatching system using this tool works well and can be implemented as the purpose of making this tool. Keywords: Arduino Uno, DHT 11, Passive Infra Red (PIR), dimmer.