Consistent and effective method to define the mouse estrous cycle stage by a deep learning-based model

The mouse estrous cycle is divided into four stages: proestrus (P), estrus (E), metestrus (M), and diestrus (D). The estrous cycle affects reproductive hormone levels in a wide variety of tissues. Therefore, to obtain reliable results from female mice, it is important to know the estrous cycle stage during sampling. The stage can be analyzed from a vaginal smear under a microscope. However, it is time-consuming, and the results vary between evaluators. Here, we present an accurate and reproducible method for staging the mouse estrous cycle in digital whole-slide images (WSIs) of vaginal smears. We developed a model using a deep convolutional neural network (CNN) in a cloud-based platform, Aiforia Create. The CNN was trained by supervised pixel-level multiclass semantic segmentation of image features from 171 hematoxylin-stained samples. The model was validated by comparing the results obtained by CNN with those of four independent researchers. The validation data included three separate studies comprising altogether 148 slides. The total agreement attested by the Fleiss kappa value between the validators and the CNN was excellent (0.75), and when D, E, and P were analyzed separately, the kappa values were 0.89, 0.79, and 0.74, respectively. The M stage is short and not well defined by the researchers. Thus, identification of the M stage by the CNN was challenging due to the lack of proper ground truth, and the kappa value was 0.26. We conclude that our model is reliable and effective for classifying the estrous cycle stages in female mice.

The lack of HSD17B3 in male mice results in disturbed Leydig cell maturation and endocrine imbalance akin to humans with HSD17B3 deficiency

Hydroxysteroid (17β) dehydrogenase type 3 (HSD17B3) deficiency causes a disorder of sex development in humans, where affected males are born with female-appearing external genitalia, but are virilized during puberty. The hormonal disturbances observed in the Hsd17b3 knockout mice (HSD17B3KO), generated in the present study, mimic those found in patients with HSD17B3 mutations. Identical to affected humans, serum T in the adult HSD17B3KO mice was within the normal range, while a striking increase was detected in serum A-dione concentration. This resulted in a marked reduction of the serum T/A-dione ratio, a diagnostic hallmark for the patients with HSD17B3 deficiency. However, unlike humans, male HSD17B3KO mice were born with normally virilized phenotype, but presenting with delayed puberty. In contrast to the current belief, data from HSD17B3KO mice show that the circulating T largely originates from the testes, indicating a strong compensatory mechanism in the absence of HSD17B3. The lack of testicular malignancies in HSD17B3KO mice supports the view that testis tumors in human patients are due to associated cryptorchidism. The HSD17B3KO mice presented also with impaired Leydig cell maturation and signs of undermasculinization in adulthood. The identical hormonal disturbances between HSD17B3 deficient knockout mice and human patients make the current mouse model valuable for understanding the mechanism of the patient phenotypes, as well as endocrinopathies and compensatory steroidogenic mechanisms in HSD17B3 deficiency.

Understanding attraction stimuli of the cat flea, Ctenocephalides felis, in non-chemical control methods

Comparisons were conducted of flea catches of four commercially available flea traps in the laboratory and under field conditions, in both rural and urban locations. The results clearly showed the My Flea Trap™, which utilizes an intermittent light to attract fleas, to be far superior in trapping ability to the three continuous light traps; it caught up to 23 times as many fleas as the other traps. Altering the lighting mechanism to provide continuous rather than intermittent light significantly decreased the number of fleas captured. In addition, the use of a green filter significantly increased trapping efficiency, whereas the addition of a heat source had no apparent effect.

Control of Culex quinquefasciatus in a storm drain system in Florida using attractive toxic sugar baits

Attractive toxic sugar baits (ATSBs) were used to control mosquitoes in the storm drains of a residential area on the outskirts of St Augustine, Florida. The drainage system was newly constructed and no mosquitoes were breeding inside it. The area covered by the storm drains was divided in half; 10 drains served as control drains and 16 drains served as experimental drains. The baits, which consisted of a mixture of brown sugar, fruit juice, green dye marker and boric acid, were presented at the entrances of the treated drains and exit traps were positioned over the drain openings and the connecting tubes leading to retention ponds. Similar baits with orange dye and without toxin were presented at the entrances of control drains. A total of 220 pupae of Culex quinquefasciatus (Diptera: Culicidae) were released in each control and toxin-treated drain, and the numbers of recovered mosquitoes were examined to determine the effectiveness of ATSBs in the storm drain system. An average of 178.2 mosquitoes exited each drain in the control area; 87.0% of these had fed on the baits and were stained orange, whereas 13.0% were unstained. In the toxin-treated drains, 83.7% of hatched females and 86.6% of hatched males were controlled by the baits.

Effective control of adult Culex pipiens by spraying an attractive toxic sugar bait solution in the vegetation near larval habitats

This study evaluated the use of an insecticide-treated fruit juice bait against adult Culex pipiens s.l. L. from sewage ponds in Israel. The attractive toxic sugar bait (ATSB) solution (fruit juice, sugar, food dye, oral insecticide spinosad, and BaitStab, a mixture of slow-release substances and preservatives) was sprayed onto 10-15% of the surrounding vegetation of these ponds. The same bait solution, without insecticide, was sprayed onto vegetation at a similar site as a control. Mosquito abundance was monitored in treatment and control sites with six CDC light traps. Mosquitoes in the experimental sites decreased from approximately 125 to approximately eight per trap. Mosquito abundance in the control sites was fairly stable and averaged approximately 60 per trap during the study. Before starting the study parity of mosquitoes from the experimental and control sites averaged approximately 20% multiparous females. After bait/insecticide application, only approximately 3% of the females were multiparous in the treatment area.