Insights and Interpretation of the Trends for <em>in ovo</em> Sexing Technologies in Papers and Patents

Abstract

Numerous researchers and institutions have been developing in ovo sexing technologies to improve animal welfare by identifying male embryos in an early embryonic stage and disposing of them before pain perception. This review gives a complete overview of the technological approaches reported in papers and patents by performing a thorough search using Web of Science and Patstat databases for papers and patents, respectively. Based on a total of 45 papers and 100 patent families up until 2021 reported worldwide, 11 technology categories were defined: six non-optical and five optical techniques. Every category was described for its characteristics while assessing its potential for application. Next, the dynamics of the publications of in ovo sexing techniques in both paper and patent fields were described through growth curves, and the interest or actual status was visualized using the number of paper citations and the actual legal status of the patents. When comparing the reported technologies in papers to those in patents, scientific gaps were observed, as some of the patented technologies were not reported in the scientific literature, e.g., ion mobility and mass spectrometry approaches. Generally, more diverse approaches in all categories were found in patents, although they do require more scientific evidence through papers or industrial adoption to prove their robustness. Moreover, although there is a recent trend for non-invasive techniques, invasive methods like analyzing DNA through PCR or hormones through immunosensing are still being reported (and might continue to be) in papers and patents. It was also observed that none of the technologies complies with all the industry requirements. Thus, more research and harmony between consumers, industry, and governments is necessary.

In Ovo Sexing of Chickens through VOCs: Assessment of System, Setup, and Day-to-Day Performance using HSSE-GC-MS, PTR-TOF-MS, and SIFT-MS

“…From all models, the JK and VIP variable selection methods yielded the highest accuracies. This is in contrast to previous work on classification using egg VOCs, where the FiPLS-created models repeatedly performed better (Corion et al, 2024). One potential explanation is that when variables inherently exhibit minimal differences between response levels, selection methods such as a JK or VIP that independently assess variables may yield more robust results on validation sets compared to a FiPLS model designed to minimize the root mean squared error of the cross-validation set, thereby excluding correlated variables.…”

“…Upon being securely airtight capped, these sorbents can be safely stored for a duration exceeding one week (Corion et al, 2024). In Experiment 1, the Twisters ® were stored in a transport block (Gerstel) at 21 °C for a maximum of 5 days, while in Experiment 2, the storage duration was limited to 2 days before undergoing analysis using GC-MS. For the HSSE-GC-MS analysis,…”

“…The overall measurement time for one sample was approximately 3.5 min. For a detailed explanation of the system validation routine, refer to Corion et al (2024). The raw signal intensities of the sample product ions were expressed in count rates (cps) and were averaged for the two sample cycles.…”

“…Concerning the PTR-TOF-MS and SIFT-MS data, a total of 299 and 692 product ions were included in the datasets, respectively. Despite the PTR-TOF-MS scanning across a broader mass range (15 -318 m/z compared to 15 -250 m/z), the SIFT-MS counted more product ions since it utilized three different reagent ions (H3O + , NO + , and O2 + ) compared to only H3O + for PTR-TOF-MS. For a more in-depth comparison of the three systems, reference is made to Corion et al (2024). Finally, each dataset included the total peak signal or total product ion signal per reagent ion as a single variable.…”

Allantoic fluid-based qPCR for early-onsetin ovosexing

“…Current in ovo sexing technologies can be categorized as optical and non-optical 12 . On the one hand, optical techniques can use visible near-infrared spectroscopy to candle the egg on days 13 or 14, distinguishing the embryos' feather colors, but these are only working on brown eggs with 99% accuracy 2 .…”