Safety and concerns of hormonal application in farm animal production: a review

Worldwide perspective for swine production and reproduction for the next 20 years

Over numerous years, breeding herds have faced challenges to sustainability with poor profitability, impact of disease, export market instability, limited labor, and increasing environmental and animal welfare regulations. Many of these scenarios are expected to continue, but their impact lessened with adjustments in management, technology, and business. The prospects for success in the future for the pig industry in various locations are based on costs of pig production efficiency and projections for domestic and export markets. Sow farms are expected to increase in size to meet large retailer needs, while smaller farms will fill domestic regional markets. The risk of PRRS in breeding herds and loss of pigs and infertility will continue to be a major concern for producers. Changes in sow housing will likely continue with designs that meet welfare requirements and allow for practical management of the breeding herd. Trends for selection and increase in litter size will continue but will include measures for birthweight and survival, and traits for heat stress and disease resistance. Changes in boar semen production and AI procedures are unlikely since fertility measures are very high. But advances in technology for identifying fertile and time of ovulation, or procedures that aid in selection of sperm or induction of ovulation, could facilitate reduction in the number of sperm used to produce a litter of pigs.

The androgen clock is an epigenetic predictor of long-term male hormone exposure

Aging is a complex process characterized by biological decline and a wide range of molecular alterations to cells, including changes to DNA methylation. In this study, we used a male-specific epigenetic marker of aging to build an epigenetic predictor that measures long-term androgen exposure in sheep and mice (median absolute error of 4.3 and 1.4 mo, respectively). We term this predictor the androgen clock and show its "tick" is mediated by the androgen receptor and can be accelerated beyond that in normal male mice by supplementing females with dihydrotestosterone. Conversely, the removal of androgens by castration in sheep completely halted the androgen clock. In addition to potential applications in medicine and agriculture, we predict the androgen clock will prove a useful model to understand the mechanisms and processes of age-associated DNA methylation change because it can be precisely enhanced and halted using small molecule manipulation with few additional effects on the cell.

Simultaneous analysis of residual prohibited doping substances in foods using gas chromatography-tandem mass spectrometry

The continuous consumption of various foods increases the risk of unintentional exposure to residual contaminants. Thus, improving premonitoring procedures to ensure food safety is critical. Herein, a rapid and efficient assay was developed to monitor residual contaminants in food, with a focus on banned doping substances. First, 73 doping compounds, including anabolic agents that can be ingested from food were selected, after which a gas chromatography-tandem mass spectrometry (GC-MS/MS) method was developed for their simultaneous screening. Based on the GC-MS/MS-determined food-matrix characteristics and types, a sample-preparation module was developed to optimize the sample-preparation method. Thereafter, the developed analytical method was validated using representative food matrices, and the results confirmed that the developed method obtained good recoveries (80-123% (limit of quantification: 0.01-20 μg kg-1)). To monitor residual doping substances in commercially available foods, the established method was applied to the analysis of 40 food samples, including meat. Notably, endogenous hormones, such as testosterone, nandrolone, 19-norandrosterone, and 19-noretiocholanolone, were detected in the meat samples, although they did not exceed the maximum residue limits. This approach enables the assessment of potential exposure levels to food-borne endogenous hormones, thereby supporting food safety and preventing unintentional doping incidents in athletes.

Ten-month comprehensive assessment of steroid hormones in the tributaries of Baiyun District, Guangzhou City, China: Spatiotemporal dynamics, source attribution, and environmental implications

The occurrence of steroid hormones in small river ecosystems raises environmental alarms due to their limited dilution capacity, heightened susceptibility to diverse pollution sources, and their substantial contribution to the contamination of larger river systems. Here, we investigated the occurrence of 40 steroid hormones over 10 months in 10 first-order tributaries (n = 250) of Guangzhou City, China. The observed concentrations of Σsteroid hormones ranged from 30.5 to 450 ng/L (mean: 55.6 ± 35.4 ng/L). No substantial variation in steroid hormone concentrations was observed between the flood and dry seasons, reflecting an intricate balance of dilution dynamics, agricultural runoff, and wastewater releases. Further correlation analysis underscored wastewater discharge as a consistent source of steroid hormone occurrence, with spikes coinciding with concurrent fertilizer application and rainfall intervals. Steroid hormone concentrations displayed significant spatial variations. Correlation analyses connected steroid hormone levels to nutrients in tributaries and agricultural ditch water and land usage, highlighting the joint effect of runoff and various wastewater types on steroid hormone distribution. Interestingly, steroid hormone levels displayed minimal variation along the tributaries, suggesting uniform and continuous pollution sources. Source attribution analysis revealed that 51.7 % of steroid hormones originated from untreated domestic wastewater, followed by treated wastewater, livestock wastewater, and runoff. Notably, 92.0 % of the sampling sites registered at least one steroid hormone level exceeding the risk quotient threshold of 1, indicating widespread ecological hazards. Our research emphasizes the persistent and stable nature of steroid hormone-related risks across seasons and along the tributaries, highlighting the imperative for vigilant monitoring. We further advocate for intensified surveillance efforts during pivotal periods (e.g., fertilization periods and low rainfall intervals), to better address these environmental challenges.

The interrelationship between macrominerals and heat stress in ruminants: current perspectives and future directions - a review

Macromineral imbalances in ruminants, particularly in tropical and subtropical regions, pose a significant challenge to production sustainability and profitability. Heat stress exacerbates these imbalances, negatively impacting physiological functions and productivity. This review examines the effects of heat stress on macromineral levels in ruminants and the need for supplementation under such conditions. Heat stress lowers key macrominerals (Na+, K+, Cl-, Ca + 2, Mg + 2, inorganic P) and disrupts acid-base balance due to thermoregulatory responses and reduced feed intake. Supplementing macrominerals to the diet to achieve higher dietary cation-anion difference helps mitigate heat-related morbidity and maintains ruminant health and productivity. A more practical approach, such as sustained-release macromineral boluses in the rumen, is proposed to provide more consistent benefits. Further researches are warranted to optimize supplementation strategies and fully understand macromineral nutrition for heat-stressed ruminants.

Determination of Hormonal Growth Promotants in Beef Using Liquid Chromatography-Tandem Mass Spectrometry

Hormonal growth promotants (HGPs) are a class of pharmaceutical agents commonly administered to cattle in the United States to improve growth rates of the animal, alter behavior, or to improve the desired characteristics of retail cuts of meat. There is a concern that low residual concentrations of HGPs may remain in tissue after slaughter, and consumption of tissues containing these compounds may increase the risk of adverse health outcomes, including cancer. Sensitive and selective methods are necessary to assess exposure of HGPs by populations that consume meat products from animals that may have been administered HGPs. A liquid chromatography-tandem mass spectrometry method was developed and validated to detect the low-level presence of HGPs including estradiol, testosterone, estradiol benzoate, melengestrol, melengestrol acetate, progesterone, testosterone propionate, trenbolone, trenbolone acetate, and α-zearalanol in retail cuts of meat following a liquid-liquid extraction using a high pH solution with 30-50× less mass of meat required as compared to similar approaches. Good chromatographic performance and sensitivity was achieved utilizing ammonium fluoride as a mobile phase additive without the need for derivatization. Validation parameters including accuracy, precision, recovery, matrix effects, limits of detection, limits of quantitation, linear range, and stability were determined. The limits of detection ranged from 0.1 to 1.0 ng/g, depending on the compound, with adequate accuracy and precision without the need for extensive sample preparation approaches.

Pharmaceutical Pollutants: Ecotoxicological Impacts and the Use of Agro-Industrial Waste for Their Removal from Aquatic Environments

Medicines are pharmaceutical substances used to treat, prevent, or relieve symptoms of different diseases in animals and humans. However, their large-scale production and use worldwide cause their release to the environment. Pharmaceutical molecules are currently considered emerging pollutants that enter water bodies due to inadequate management, affecting water quality and generating adverse effects on aquatic organisms. Hence, different alternatives for pharmaceuticals removal from water have been sought; among them, the use of agro-industrial wastes has been proposed, mainly because of its high availability and low cost. This review highlights the adverse ecotoxicological effects related to the presence of different pharmaceuticals on aquatic environments and analyzes 94 investigations, from 2012 to 2024, on the removal of 17 antibiotics, highlighting sulfamethoxazole as the most reported, as well as 6 non-steroidal anti-inflammatory drugs (NSAIDs) such as diclofenac and ibuprofen, and 27 pharmaceutical drugs with different pharmacological activities. The removal of these drugs was evaluated using agro-industrial wastes such as wheat straw, mung bean husk, bagasse, bamboo, olive stones, rice straw, pinewood, rice husk, among others. On average, 60% of the agro-industrial wastes were transformed into biochar to be used as a biosorbents for pharmaceuticals removal. The diversity in experimental conditions among the removal studies makes it difficult to stablish which agro-industrial waste has the greatest removal capacity; therefore, in this review, the drug mass removal rate (DMRR) was calculated, a parameter used with comparative purposes. Almond shell-activated biochar showed the highest removal rate for antibiotics (1940 mg/g·h), while cork powder (CP) (10,420 mg/g·h) showed the highest for NSAIDs. Therefore, scientific evidence demonstrates that agro-industrial waste is a promising alternative for the removal of emerging pollutants such as pharmaceuticals substances.

Ecological consequences of antimicrobial residues and bioactive chemicals on antimicrobial resistance in agroecosystems

BACKGROUND

The widespread use of antimicrobials in agriculture, coupled with bioactive chemicals like pesticides and growth-promoting agents, has accelerated the global crisis of antimicrobial resistance (AMR). Agroecosystems provides a platform in the evolution and dissemination of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs), which pose significant threats to both environmental and public health.

AIM OF REVIEW

This review explores the ecological consequences of antimicrobial residues and bioactive chemicals in agroecosystems, with a focus on their role in shaping AMR. It delves into the mechanisms by which these substances enter agricultural environments, their interactions with soil microbiomes, and the subsequent impacts on microbial community structure.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Evidence indicates that the accumulation of antimicrobials promotes resistance gene transfer among microorganisms, potentially compromising ecosystem health and agricultural productivity. By synthesizing current research, we identify critical gaps in knowledge and propose strategies for mitigating the ecological risks associated with antimicrobial residues. Moreover, this review highlights the urgent need for integrated management approaches to preserve ecosystem health and combat the spread of AMR in agricultural settings.

Cellulose as a sustainable scaffold material in cultivated meat production

The rapid progress in cultivated meat research has engendered considerable attention towards the edible scaffolding biomaterials employed in the production. Cellulose has the advantages in availability, edibility, animal-free origin, etc., which show its potential in wide fields. This review begins by presenting the fundamental physical and chemical properties of cellulose from different sources, including plant and bacterial cellulose. Subsequently, we summarize the application of cellulose especially in cultivated meat and tissue engineering. Furthermore, we explore various methods for preparing cellulose-based scaffolds for cultivated meat, encompassing five specific structural variations. In the end, associated with utilizing cellulose in cultivated meat production, we address several primary challenges surrounding to cell adhesion, scaling up, processibility and mechanical properties, and provide potential innovations. This review underscores the potential of cellulose as a versatile biomaterial in the cultivated meat industry and provides insight into addressing critical challenges for its integration.

Occurrence and Prioritization of Human Androgen Receptor Disruptors in Sewage Sludges Across China

The global practice of reusing sewage sludge in agriculture and its landfill disposal reintroduces environmental contaminants, posing risks to human and ecological health. This study screened sewage sludge from 30 Chinese cities for androgen receptor (AR) disruptors, utilizing a disruptor list from the Toxicology in the 21st Century program (Tox21), and identified 25 agonists and 33 antagonists across diverse use categories. Predominantly, natural products 5α-dihydrotestosterone and thymidine emerged as agonists, whereas the industrial intermediate caprolactam was the principal antagonist. In-house bioassays for identified disruptors displayed good alignment with Tox21 potency data, validating employing Tox21 toxicity data for theoretical toxicity estimations. Potency calculations revealed 5α-dihydrotestosterone and two pharmaceuticals (17β-trenbolone and testosterone isocaproate) as the most potent AR agonists and three dyes (rhodamine 6G, Victoria blue BO, and gentian violet) as antagonists. Theoretical effect contribution evaluations prioritized 5α-dihydrotestosterone and testosterone isocaproate as high-risk AR agonists and caprolactam, rhodamine 6G, and 8-hydroxyquinoline (as a biocide and a preservative) as key antagonists. Notably, 16 agonists and 20 antagonists were newly reported in the sludge, many exhibiting significant detection frequencies, concentrations, and/or toxicities, demanding future scrutiny. Our study presents an efficient strategy for estimating environmental sample toxicity and identifying key toxicants, thereby supporting the development of appropriate sludge management strategies.

A nitrogen-doped hollow carbon nanospheres-based aptasensor for non-invasive salivary detection of progesterone

Developing an easy-to-use and non-invasive sensor for monitoring progesterone (P4) as a multi-functional hormone is highly demanded for point-of-care testing. In this study, an ultrasensitive electrochemical aptasensor is fabricated for monitoring P4 in human biofluids. The sensing interface was designed based on the porous nitrogen-doped hollow carbon spheres (N-HCSs). The N-HCSs covalently immobilized high-dense aptamer (Apt) sequences as the bioreceptor of P4. The electron transfer of the redox probe was hindered by incubating P4 on the aptasensor surface and forming the P4-Apt complexes. Meanwhile, the signaling was decreased under two wide linear dynamic ranges (LDRs) from 10 fM to 5.6 μM with a limit of detection (LOD) value of 3.33 fM. The aptasensor presented satisfactory selectivity in the presence of different off-target species with successful feasibility for P4 detection in some human urine and saliva samples. The aptasensor with high sensitivity, as an advantage for on-site and sensitive measurement of P4, can be considered a non-invasive tool for routine analysis of real-world clinical samples method.

Social, ethical, environmental, economic and technological aspects of rabbit meat production - A critical review

Rabbit (RM) has become a valuable source of nutrients since the 1970s, helping to transform the European food industry into the largest RM producer in the world. However, the RM industry is experiencing a critical period of ethical imbalance. This trend, described as feed conversion ratio, impacts the environmental and financial performance of RM farms, which could lead to an increase production of industrial waste. In addition, the loss of corporate ethical responsibility and sustainable development by RM-oriented companies has further exacerbated the situation. Our objective was to summarize current trends in the RM industry and markets, highlighting possible strengths and weaknesses. This review shows current approaches in sustainable techniques in RM production processes, ethical issue, environmental and processing responsibility of RM producers, as well as social responsibilities and ethical practices of slaughterhouses and RM producers, sustainable environmental practices of slaughterhouses, technological aspects and safety of RM and social drivers in RM market. The analysis of reviewed literature revealed the potential strategies for sustainable RM production.

RNAseq Analysis of Livers from Pigs Treated with Testosterone and Nandrolone Esters: Selection and Field Validation of Transcriptional Biomarkers

The use of anabolic-androgenic steroids (AASs) as growth promoters in farm animals is banned in the European Union, representing both an illicit practice and a risk for consumer health. However, these compounds are still illegally administered, often in the form of synthetic esters. This work aimed to characterize significant coding RNA perturbations related to the illicit administration of testosterone and nandrolone esters in fattening pigs. A total of 27 clinically healthy 90-day-old pigs were randomly assigned to test and control groups. Nine animals were treated with testosterone esters (Sustanon®) and other nine with nandrolone esters (Myodine®). At the end of the trial, liver samples were collected and analyzed using RNAseq, allowing the identification of 491 differentially expressed genes (DEGs). The transcriptional signature was further characterized by a smaller sub-cluster of 143 DEGs, from which a selection of 16 genes was made. The qPCR analysis confirmed that the identified cluster could still give good discrimination between untreated gilt and barrows compared to the relative testosterone-treated counterparts. A conclusive field survey on 67 liver samples collected from pigs of different breeds and weight categories confirmed, in agreement with testosterone residue profiles, the specificity of selected transcriptional biomarkers, showing their potential applications for screening purposes when AAS treatment is suspected, allowing to focus further investigations of competent authorities and confirmatory analysis where needed.

Deleterious effect of gestagens from wastewater effluent on fish reproduction in aquatic environment: A review

Gestagens are common pollutants accumulated in the aquatic ecosystem. Gestagens are comprised of natural gestagens (i.e. progesterone) and synthetic gestagens (i.e. progestins). The major contributors of gestagens in the environment are paper plant mill effluent, wastewater treatment plants, discharge from pharmaceutical manufacturing, and livestock farming. Gestagens present in the aquatic environment interact with progesterone receptors and other steroid hormone receptors, negatively influencing fish reproduction, development, and behavior. In fish, the gonadotropin induces 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) production, an important steroid hormone involved in gametogenesis. DHP interacts with the membrane progestin receptor (mPR), which regulates sperm motility and oocyte maturation. Gestagens also interfere with the hypothalamic-pituitary-gonadal (HPG) axis, which results in altered hormone levels in fish. Moreover, recent studies showed that even at low concentrations exposure to gestagens can have detrimental effects on fish reproduction, including reduced egg production, masculinization, feminization in males, and altered sex ratio, raising concerns about their impact on the fish population. This review highlights the hormonal regulation of sperm motility, oocyte maturation, the concentration of environmental gestagens in the aquatic environment, and their detrimental effects on fish reproduction. However, the long-term and combined impacts of multiple gestagens, including their interactions with other pollutants on fish populations and ecosystems are not well understood. The lack of standardized regulations and monitoring protocols for gestagens pollution in wastewater effluent hampers effective control and management. Nonetheless, advancements in analytical techniques and biomonitoring methods provide potential solutions by enabling better detection and quantification of gestagens in aquatic ecosystems.

Association of MTNR1A and GDF9 gene allelles with the reproductive performance, response to oestrus induction treatments and prolificacy, in improved and non-improved local indigenous sheep breeds

Sheep farming plays a crucial role for Mediterranean countries, wherefrom a plethora of dairy products is produced. Yet, numerous indigenous sheep breeds in temperate latitudes such as the Mediterranean present a serious drawback that milk production is impaired by the seasonality of reproduction. Towards the efforts for reduction of this phenomenon, the purpose of this study was to evaluate and compare different oestrus synchronization treatments, as well as to associate two genes alleles', namely the MTNR1A and the GDF9, with the response to those treatments. Three indigenous breeds were investigated (Florina, Chios and Karagouniko sheep) and inside each breed three different oestrus synchronization treatments were applied (A: intravaginal sponges, B: GNRH use and C: male effect). In group A, Florina ewes expressed oestrus at 90% in July and fecundity was 85%. Karagouniko and Chios ewes exhibited an oestrus expression of 100% with fecundity rates at 95% and 99%, respectively. In group B, Florina ewes expressed oestrus at 60% with fecundity at 57%, Karagouniko ewes expressed oestrus at 65% with fecundity at 54%, whereas Chios breed animals expressed oestrus at 87% with fecundity rate at 85%. In group C, 68% of the Florina breed expressed oestrus 20-25 days post ram induction, whereas this proportion was 84% and 94%, for Karagouniko and Chios breed, respectively. For the molecular analysis, partial segments of the two genes were sequenced and analysed, whereas alleles were scored based on the detected SNPs. All frequencies of the four detected SNPs in MTNR1A gene were statistically and significantly different in ewes that expressed oestrus in comparison with ewes that did not express oestrus in Florina and Karagouniko breeds concerning all treatments. Two SNP's were detected in GDF9 gene, G1 and FecG , from which, only the FecG mutation exhibited statistically significant difference in twins and triplets than in singles in Florina and Karagouniko breeds.

Anabolic Steroids in Fattening Food-Producing Animals—A Review

Simple Summary

Anabolic steroids significantly affect animal tissues and cause morphological and histological changes, which are often irreversible. This issue is currently a very hot topic, as the answers to the questions concerning the health of endangered animals and humans vary greatly from country to country. There is a need to further investigate whether the use of anabolic steroids in animal fattening threatens consumer health and to develop new tools for the detection of anabolic steroids in meat. One possibility for detection could be to observe histological changes in the tissues, which form a typical pattern of anabolic abuse. This review gathered information on the anabolic steroids most commonly used in animal fattening, the legislation governing this issue, and the main effects of anabolics on animal tissues.

Abstract

Anabolic steroids are chemically synthetic derivatives of the male sex hormone testosterone. They are used in medicine for their ability to support muscle growth and healing and by athletes for esthetic purposes and to increase sports performance, but another major use is in fattening animals to increase meat production. The more people there are on Earth, the greater the need for meat production and anabolic steroids accelerate the growth of animals and, most importantly, increase the amount of muscle mass. Anabolic steroids also have proven side effects that affect all organs and tissues, such as liver and kidney parenchymal damage, heart muscle degeneration, organ growth, coagulation disorders, and increased risk of muscle and tendon rupture. Anabolic steroids also have a number of harmful effects on the developing brain, such as brain atrophy and changes in gene expression with consequent changes in the neural circuits involved in cognitive functions. Behavioral changes such as aggression, irritability, anxiety and depression are related to changes in the brain. In terms of long-term toxicity, the greatest impact is on the reproductive system, i.e., testicular shrinkage and infertility. Therefore, their abuse can be considered a public health problem. In many countries around the world, such as the United States, Canada, China, Argentina, Australia, and other large meat producers, the use of steroids is permitted but in all countries of the European Union there is a strict ban on the use of anabolic steroids in fattening animals. Meat from a lot of countries must be carefully inspected and monitored for steroids before export to Europe. Gas or liquid chromatography methods in combination with mass spectrometry detectors and immunochemical methods are most often used for the analysis of these substances. These methods have been considered the most modern for decades, but can be completely ineffective if they face new synthetic steroid derivatives and want to meet meat safety requirements. The problem of last years is the application of “cocktails” of anabolic substances with very low concentrations, which are difficult to detect and are difficult to quantify using conventional detection methods. This is the reason why scientists are trying to find new methods of detection, mainly based on changes in the structure of tissues and cells and their metabolism. This review gathered this knowledge into a coherent form and its findings could help in finding such a combination of changes in tissues that would form a typical picture for evidence of anabolic misuse.