Estimating yolk weight of duck eggs using VIS-NIR Spectroscopy and RGB images and whole egg weights.

Duck eggs are widely-consumed food and cooking ingredient. The heavier yolk weight (YW) corresponds to a larger size and greater value. However, there is no nondestructive method available to estimate the weight of the yolk. Accurate weight prediction of duck egg yolks must combine both phenotypic and internal information. In this research, we used Visible-Near Infrared (VIS-NIR) spectroscopy to obtain internal information of duck eggs, and a high-definition camera to capture their phenotypic features. YW was predicted by combining the reduced spectral and RGB image information with the whole egg weight. We also investigated the impact of color and thickness of the duck egg on spectral transmittance (ST), as these factors can influence the extent of ST. The results showed that the spectral curves of duck eggs produced 2 peaks and 1 valley, which may be caused by the dual-frequency absorption of the C-H group and O-H group, and can be used to symbolize the internal information of duck eggs. The ST was somewhat affected by the color and thickness of the duck eggshell. Before modelling, Principal component analysis (PCA) was used to significantly reduce the dimensionality of the RGB image with spectral data. A partial least squares regression (PLSR) model was utilized to fit all the features. The test set yielded a coefficient of determination (R2) of 0.82 and a Root Mean Squared Error (RMSE) of 1.05 g. After removing the eggshell's color and thickness features, the model showed an R2 of 0.79 and an RMSE of 1.11 g. This study demonstrated that the yolk weight of duck eggs can be estimated using VIS-NIR spectroscopy, RGB images and whole egg weight. Furthermore, the effects of shell color and thickness can be neglected.

Sex identification of ducklings based on acoustic signals.

Sex identification of ducklings is a critical step in the poultry farming industry, and accurate sex identification is beneficial for precise breeding and cost savings. In this study, a method for identifying the sex of ducklings based on acoustic signals was proposed. In the first step, duckling vocalizations were collected and an improved spectral subtraction method and high-pass filtering were applied to reduce the influence of noise. Then, duckling vocalizations were automatically detected by using a double-threshold endpoint detection method with 3 parameters: short-time energy (STE), short-time zero-crossing rate (ZCR), and duration (D). Following the extraction of Mel-Spectrogram features from duckling vocalizations, an improved Res2Net deep learning algorithm was used for sex classification. This algorithm was introduced with the Squeeze-and-Excitation (SE) attention mechanism and Ghost module to improve the bottleneck of Res2Net, thereby improving the model accuracy and reducing the number of parameters. The ablative experimental results showed that the introduction of the SE attention mechanism improved the model accuracy by 2.01%, while the Ghost module reduced the number of model parameters by 7.26M and the FLOPs by 0.85G. Moreover, this algorithm was compared with 5 state-of-the-art (SOTA) algorithms, and the results showed that the proposed algorithm has the best cost-effectiveness, with accuracy, recall, specificity, number of parameters, and FLOPs of 94.80, 94.92, 94.69, 18.91M, and 3.46G, respectively. After that, the vocalization detection score and the average confidence strategy were used to predict the sex of individual ducklings, and the accuracy of the proposed model reached 96.67%. In conclusion, the method proposed in this study can effectively detect the sex of ducklings and serve as a reference for automated sex identification of ducklings.

Inhibitory effects of 5-hydroxytryptamine microinjection into thalamic nucleus submedius on rat tail flick reflex are mediated by 5-HT2 receptors.

Our previous findings indicated that electrical or chemical activation of the thalamic nucleus submedius (Sm) produced significant antinociceptive effects and that these effect were blocked by lesion or depression of the ventrolateral orbital cortex (VLO) or the periaqueductal gray (PAG) suggesting a role of the Sm in modulation of nociception. To further investigate the neurotransmitter mechanism involved in this nociceptive modulatory pathway, we tested the effects of microinjection of 5-hydroxytryptamine (5-HT, 50 mM, 0.5 microl) into Sm on the tail flick (TF) reflex. The results show that a unilateral microinjection of 5-HT into Sm significantly depresses the TF reflex; and that this effect is repeatable and dose-dependent. Furthermore, microinjection of 5-HT2 receptor antagonist cyproheptadine (CPT, 0.3 mM, 0.5 microl) into the same Sm site reverses this 5-HT-evoked inhibition of TF reflex. These results suggest that 5-HT application to the Sm may activate Sm neurons through the 5-HT2 receptors leading to activation of the brainstem descending inhibitory system via the VLO and depression of the nociceptive information at the spinal level.