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Artificial insemination (AI) has become a popular technique in rabbit farms worldwide. This report discusses the progress made on semen extenders used in rabbit AI, setting out the latest innovations. Fresh and frozen semen have different requirements, so the extender composition will vary depending on the type of semen used. We discuss the endocrine supplementation of extenders for ovulation induction, the use of active molecules as an alternative to conventional antibiotics and the extenders developed for rabbit sperm cryopreservation.

The development of reproductive technologies in this species is contributing decisively to the development of rabbit farming and the preservation of genetic resources. Obtaining embryos is an essential step to both genetic diffusion and the preservation of genetic resources from genetic erosion or natural disasters. In rabbits, it is common for embryos to be recovered post-mortem after ovarian hyperstimulation with gonadotrophins, although the quality and number of embryos are variable, affecting the embryo viability and offspring rate by the donor. In vivo embryo production within a conservation programme aims not only to obtain a large number of embryos, but also that they come from a greater number of male and female origins, in order to ensure an adequate representation of the original population. This is why both the quality and quantity of embryos obtained per donor rabbit and the rate of donors with offspring after embryo cryopreservation must be considered, as well as the response of the embryos to the chemical, physical and physiological stress to which they are subjected in the rederivation process and its postnatal repercussions on those that survive. Rederived rabbits from cryopreserved and transferred embryos showed phenotypic growth changes, which calls into question the neutrality of the technique and its usefulness in those cases in which a control population is required.

Se explora el significativo impacto que la Inteligencia Artificial (IA) ha tenido en la segmentación y el targeting de las campañas políticas, los casos reales de aplicación en el pasado y las tendencias que nos depara el futuro inmediato. La IA ha revolucionado la segmentación, permitiendo un enfoque de micro-segmentación que divide el electorado en grupos más pequeños basados en patrones de comportamiento, intereses y creencias individuales. En cuanto al targeting, la IA ha mejorado la precisión y la eficiencia, facilitando la predicción del comportamiento electoral y permitiendo pruebas A/B de diferentes mensajes. Sin embargo, este uso de la IA plantea desafíos éticos y de privacidad, incluyendo preocupaciones sobre la protección de datos y la manipulación política. A medida que la tecnología avanza, es crucial que los responsables políticos y los legisladores sigan el ritmo para garantizar la integridad y la justicia del proceso electoral.

Rabbits have played a significant role in both livestock production and the advancement of reproductive scientific research. Their unique biological traits, including induced ovulation and a reproductive process that closely mirrors that of humans, have been pivotal in their use as a model. Moreover, their body size is perfectly aligned with the 3Rs principles: Replacement, Reduction, and Refinement. Consequently, techniques for gamete collection and embryo recovery, followed by their use in artificial insemination or embryo transfer, are characterized by being minimally invasive. However, refining in vitro fertilization and embryo culture techniques continues to present challenges. The incorporation of cutting‐edge genomic editing tools, such as CRISPR/Cas9, has reestablished rabbits as essential models in genetic and biomedical research, driving scientific progress. This review aims to describe the most effective reproductive biotechnologies for both male and female rabbits and how these methodologies are in line with the 3Rs principles—Replacement, Reduction, and Refinement—highlighting their significance in conducting ethical research. [ABSTRACT FROM AUTHOR]

Gonadotropin‐releasing hormone (GnRH) ‐supplemented extenders have emerged as a welfare‐orientated method to induce ovulation in the artificial insemination (AI) of rabbits. The main factor that limits the bioavailability of GnRH analogue on intravaginal administration is the proteolytic activity of enzymes present in rabbit seminal plasma. The use of GnRH analogues with higher biological potency would allow us to decrease their concentration in the seminal dose without compromising effectiveness. The current study was designed to assess the efficacy of various GnRH analogues concerning their ability to induce ovulation in rabbit AI. The base solution used for experimental extenders contained an aminopeptidase inhibitor. Four experimental groups were used, females from the Control group were induced to ovulate with an intramuscular administration of 1 μg of buserelin, while in the other three groups females received an intravaginal administration of 3.5 μg of buserelin (BUS), deslorelin (DES) or fertirelin (FER) within the seminal dose. Results showed that the ovulation frequency was similar in all groups studied. A concentration of 3.5 μg of the different GnRH analogues tested in this study showed similar potency in inducing ovulation in non‐lactating females, yielding comparable results in terms of pregnancy rate at birth and prolificacy. [ABSTRACT FROM AUTHOR]

This paper presents a new Remote Hyperspectral Imaging System (RHIS) embedded on an Unmanned Aquatic Drone (UAD) for plastic detection and identification in coastal and freshwater environments. This original system, namely the Remotely Operated Vehicle of the University of Littoral Côte d’Opale (ROV-ULCO), works in a near-field of view, where the distance between the hyperspectral camera and the water surface is about 45 cm. In this paper, the new ROV-ULCO system with all its components is firstly presented. Then, a hyperspectral image database of plastic litter acquired with this system is described. This database contains hyperspectral data cubes of different plastic types and polymers corresponding to the most-common plastic litter items found in aquatic environments. An in situ spectral analysis was conducted from this benchmark database to characterize the hyperspectral reflectance of these items in order to identify the absorption feature wavelengths for each type of plastic. Finally, the ability of our original system RHIS to automatically recognize different types of plastic litter was assessed by applying different supervised machine learning methods on a set of representative image patches of marine litter. The obtained results highlighted the plastic litter classification capability with an overall accuracy close to 90%. This paper showed that the newly presented RHIS coupled with the UAD is a promising approach to identify plastic waste in aquatic environments.

Rabbit is a reflexively ovulating species. Accordingly, in the practice of artificial insemination (AI) ovulation must be induced via exogenous GnRH (Gonadotropin-Releasing Hormone) administration, which may be performed intramuscularly, subcutaneously, or intravaginally. Unfortunately, the bioavailability of the GnRH analogue when added to the extender is lower due to the proteolytic activity in the seminal plasma and the poor permeability of the vaginal mucosa. The aim of the study was to refine the practice of AI practice in rabbits by replacing parenteral GnRH analogue administration (subcutaneous, intravenous, or intramuscular injection) with intravaginal application, while reducing its concentration in the diluent. Extenders containing the buserelin acetate in chitosan–dextran sulphate and chitosan–alginate nanoparticles were designed and 356 females were inseminated. Reproductive performance of females inseminated with the two experimental extenders, receiving 4 μg of buserelin acetate intravaginally per doe, was compared with that in the control group, the does of which were inseminated with the extender without the GnRH analogue and induced to ovulate with 1 μg of buserelin acetate administered intramuscularly. The entrapment efficiency of the chitosan–dextran sulphate complex was higher than that of chitosan–alginate. However, females inseminated with both systems showed similar reproductive performance. We conclude that both nanoencapsulation systems are an efficient way of intravaginal ovulation induction, allowing a reduction in the level of the GnRH analogue normally used in seminal doses from 15–25 μg to 4 μg.

The rapid growth of the elderly population, associated with longer life expectancy, is associated with a higher prevalence of chronic non-communicable diseases, such as those of the cardiovascular, renal system and neoplasms. A large portion of these pathologies require hospitalization and their conditions require the use of antibiotics (ATB), whose indiscriminate use can lead to Acute Kidney Injury (AKI), which has serum creatinine as one of its markers. Therefore, the present study aimed to evaluate changes in serum creatinine of hospitalized elderly people submitted to antibiotic therapy in a university hospital. This was a cross-sectional study in which patients over 60 years old were identified during a period of 6 months and who used ATB, as well as had their serum creatinine measured. The variables age, gender, length of hospital stays and use of ATB were considered, as well as serum creatinine values before and after antibiotic therapy. A total of 796 patients participated in the study, 51.4% (409) of whom were male. Ages ranged from 60 to 109 years, with an average of 74.9 (± 9.6). It was identified that length of stay and use of ATB are variables that interfere with the increase in creatinine due to antibiotic therapy, which was observed in 75.5% of the patients. This leads to the reflection about a possible indiscriminate prescription of antimicrobials and their correlation to AKI.

Aim: To investigate the effect of resistance training (RT) on hepatocardiovascular and muscle mitochondrial parameters in rats that were fed a high-calorie diet for 12 weeks. Main methods: The animals were divided into four groups: control (C), exercise (E), obese (O), and obese plus exercise (OE). Group E and OE rats performed resistance training by climbing on a vertical ladder with load attached to the end of the tail (1×/day, 3×/week, for 12 weeks). Group O and OE rats were fed a high-calorie diet containing chow and a cafeteria diet for 12 weeks. Under anesthesia, the heart and liver were removed for histopathological analysis, and the gastrocnemius muscle was removed for Western blotting. Key findings: Group O rats were heavier, with increased fat mass, elevated fasting glycemia, and total triglycerides, and exhibited a significant number of Kupffer cells and diffuse steatosis in the liver. Group O rats also showed increased thickness of the right ventricle, septum, and pulmonary artery. All of these parameters were attenuated by RT. PGC1-α protein levels were increased in both exercise groups. The protein levels of OXPHOS complexes III, IV, and V were reduced in Group O, while RT prevented this alteration. Significance: RT exerts a protective effect against hepato-cardiac alterations and prevents changes in the muscle mitochondrial protein profile induced by a high-calorie diet.