Animals

15 pages, 2246 KB

Open AccessArticle

Persistence and Dissemination of Enrofloxacin and Ciprofloxacin Residues: The Hidden Role of Litter and Droppings in the Emergence of Antimicrobial Resistance

by María Belén Vargas, Camila Nettle, Ignacia Soto, Ekaterina Pokrant, Aldo Maddaleno, Lisette Lapierre and Javiera Cornejo

Animals 2026, 16(2), 333; https://doi.org/10.3390/ani16020333 (registering DOI) - 21 Jan 2026

Abstract

The objective of this study was to evaluate the persistence and environmental dissemination of enrofloxacin (EFX) and its metabolite ciprofloxacin (CFX) residues in poultry systems, as well as their effect on antimicrobial resistance in Escherichia coli. The experimental design included three groups: [...] Read more.

The objective of this study was to evaluate the persistence and environmental dissemination of enrofloxacin (EFX) and its metabolite ciprofloxacin (CFX) residues in poultry systems, as well as their effect on antimicrobial resistance in Escherichia coli. The experimental design included three groups: one treated group (A) and two untreated groups (B.1 and B.2), located in pens adjacent to or within 30 cm of group A to assess residue transfer. Birds in group A received EFX orally (10 mg·kg⁻¹ every 24 h for 5 days) via orogastric tube. EFX and CFX residues persisted in litter and excreta for up to 18 days post-treatment, reaching initial concentrations of 20,968 µg·kg⁻¹ in litter and 884.8 µg·kg⁻¹ in droppings in group A. Significant differences were detected between groups (Kruskal–Wallis, p < 0.05), confirming greater accumulation in the treated group and environmental dissemination. E. coli isolates obtained from litter and droppings from group A showed 73% resistance after treatment and correlated positively with residue concentration (ρ = 0.53). While the untreated groups B.1 and B.2 showed resistance rates of 24% and 13%, respectively, the control group exhibited a resistance rate of 3.3%. This study shows the detection of low levels of EXF and CFX residues in the litter of untreated groups, indicating limited dispersion. These findings highlight the importance of proper byproduct management and targeted environmental monitoring within the One Health framework, as continuous environmental exposure over time, combined with the persistence of this compound, may contribute to the selection of resistant bacteria. Full article

(This article belongs to the Section Poultry)

10 pages, 1136 KB

Open AccessArticle

Sexual Dimorphism in Three Populations of the Chiala Mountain Salamander, Batrachuperus karlschmidti (Caudata: Hynobiidae)

by Xiuying Liu, Chunhao Shen, Yuanhua Xu, Jian Song, Min Lou and Jianli Xiong

Animals 2026, 16(2), 332; https://doi.org/10.3390/ani16020332 - 21 Jan 2026

Abstract

Sexual dimorphism (SD) is a widespread phenomenon among animals and has attracted considerable interest in evolutionary biology. Most studies on SD have been limited to a single population, and few have focused on multiple populations. In this study, size and shape SD were [...] Read more.

Sexual dimorphism (SD) is a widespread phenomenon among animals and has attracted considerable interest in evolutionary biology. Most studies on SD have been limited to a single population, and few have focused on multiple populations. In this study, size and shape SD were evaluated in three populations of Batrachuperus karlschmidti, a hynobiid species endemic to China. SD was not found in body size, but was observed in body shape. Males had larger relative dimensions in head length, head width, forelimb length, forelimb width, hindlimb length, hindlimb width, and tail length. Conversely, females were larger in the relative dimension of interlimb distance. Sexual selection can account for SD in head and limbs, thereby enhancing male reproductive success. Conversely, fecundity selection drives SD in limbs, tail length, and interlimb distance, ultimately improving the reproductive ability of both sexes. Differences in sexual shape dimorphism (SShD) traits were also found among populations, which may be caused by dissimilar levels of selection forces in the environment. This study provides insight into identifying the causes that promote sexual dimorphism, as well as the degree of difference in SShD traits among populations. Full article

(This article belongs to the Section Herpetology)

17 pages, 969 KB

Open AccessArticle

Microscopic and Molecular Identification of Sarcocystis Species in Wild Brown Rats (Rattus norvegicus) in Lithuania and Latvia

by Giedrius Šidlauskas, Evelina Juozaitytė-Ngugu, Dalius Butkauskas and Petras Prakas

Animals 2026, 16(2), 331; https://doi.org/10.3390/ani16020331 - 21 Jan 2026

Abstract

Sarcocystis is a genus of heteroxenous, globally distributed apicomplexan parasites found in reptiles, birds, and mammals. Typically, sarcocysts develop in muscles of intermediate hosts, and oocysts sporulate in intestines of definitive hosts. The parasite’s life cycle is based on prey–predator relationships and usually [...] Read more.

Sarcocystis is a genus of heteroxenous, globally distributed apicomplexan parasites found in reptiles, birds, and mammals. Typically, sarcocysts develop in muscles of intermediate hosts, and oocysts sporulate in intestines of definitive hosts. The parasite’s life cycle is based on prey–predator relationships and usually involves two distinct host species. However, some Sarcocystis spp. can complete their full development within a single host species. Brown rats (Rattus norvegicus) are invasive, synanthropic, highly adaptable rodents that are true omnivores and opportunistic feeders. Therefore, it is possible that they can act as definitive hosts of Sarcocystis parasites. This study provides the first comprehensive assessment of Sarcocystis protists in brown rat intestinal samples under natural conditions, combining microscopy and molecular analyses. Of 27 brown rats investigated, 25.9% (7/27) of animals harbored oocysts/sporocysts of Sarcocystis spp. Based on nested PCR and sequencing of four genetic loci (18S rRNA, 28S rRNA, ITS1, and cox1), 59.3% of samples were positive for Sarcocystis spp. Parasites identified were genetically similar to Sarcocystis spp. using bird–bird, bird–Carnivora, rodent–Carnivora, or ungulate–Carnivora as their intermediate–definitive hosts. The present study suggests that synanthropic rodents may facilitate cross-ecosystem transmission of these parasites, increasing infection pressure on livestock, companion animals, and wildlife in human-dominated environments. Future molecular and dietary ecological studies are needed to assess the role of synanthropic and opportunistic hosts, such as the brown rat, in the transmission of Sarcocystis spp. Full article

(This article belongs to the Section Veterinary Clinical Studies)

20 pages, 771 KB

Open AccessArticle

Evaluation of Different Terrestrial Oils as an Alternative to Dietary Fish Oil on Feed Physical Properties, Growth, Feed Utilization, and Fatty Acid Profile of Gangetic Catfish (Mystus cavasius)

by Sadia Taslim Helen, Tanwi Dey, Anwesha Bharoteshwari, Kazi Rakib Uddin, Muhammad Anamul Kabir, Md. Rakibul Hasan and Md. Sakhawat Hossain

Animals 2026, 16(2), 330; https://doi.org/10.3390/ani16020330 - 21 Jan 2026

Abstract

The global demand for fish oil (FO) is increasing while its supply is decreasing, which has limited its use in aquafeeds. Research on alternative terrestrial oils (TOs) for commonly cultured fish species in Bangladesh is limited. This research involved a 70-day feeding experiment [...] Read more.

The global demand for fish oil (FO) is increasing while its supply is decreasing, which has limited its use in aquafeeds. Research on alternative terrestrial oils (TOs) for commonly cultured fish species in Bangladesh is limited. This research involved a 70-day feeding experiment to assess the effectiveness of replacing FO with TOs in the diet of Gangetic catfish (Mystus cavasius). Five diets were formulated: a control diet (D1) with fish meal and FO, and four diets replacing FO with soybean oil (D2), black soldier fly larvae oil (D3), palm oil (D4), or a mixed oil combination (D5) of 50% black soldier fly larvae oil, 25% soybean oil, and 25% palm oil. A total of 675 fish (0.5 g each) were distributed in 15 100 L aquariums (45 fish/aquarium) and fed to satiation twice daily. Fish fed with Diet D5 showed significantly higher growth, followed by those fed with D3, D4, and D1, while D2 resulted in significantly lower growth. Fish on the D5 diet consumed the most feed, followed by those on the D3 and D2 diets, with similar feed intake levels for those on the D1 and D4 diets. FCR, FCE, and PER were not significantly affected by dietary oil sources. Whole-body lipid content (p < 0.05) was significantly lower in the D3 group and higher in the D2 group, while other groups showed intermediate values. The fatty acid composition in the fish reflected their diets: significantly higher n-3 LC-PUFA (EPA + DHA) content was observed in the D1 group, followed by the D4 and D3 groups, and fish fed with D2 and D5 showed significantly lower values. Alpha-linolenic acid C18:3n-3) was significantly higher in the D2 group, followed by the D3, D1, and D4 groups, with the D5 group having a significantly lower value. Total MUFA was significantly higher in D4, followed by D1, D5, and D3; the D2-fed group showed a significantly lower value. Lauric acid (C12:0) was significantly higher in D3, followed by D5; other groups showed significantly lower values. Feed physical properties were significantly influenced by oil type, with water stability, pellet durability, and palatability being significantly highest in the D2 and D5 diets, followed by D3 and D4, with D1 being the lowest. Fish on the D1 and D5 diets had a significantly higher condition factor (CF) compared to fish on the D2 diet. Considering the growth and overall performance in the current study, we concluded that under the current dietary composition, TOs can effectively replace FO in the diets of Gangetic catfish, with mixed oils, black soldier fly larvae oil, and palm oil being the most promising alternatives. Full article

(This article belongs to the Section Animal Nutrition)

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11 pages, 236 KB

Open AccessArticle

Effects of Dendrobium officinale Leaf Powder on Bone Health and Bone Metabolism in Laying Hens

by Yutao Wu, Bingji Xu, Haoxin Zhang, Wen Ge, Ayong Zhao, Han Wang and Feifei Yan

Animals 2026, 16(2), 329; https://doi.org/10.3390/ani16020329 - 21 Jan 2026

Abstract

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional Chinese medicinal herb with recognized anti-inflammatory, antioxidant, and immunomodulatory properties. This study evaluated whether dietary supplementation with D. officinale leaf powder could influence bone mass, mechanical strength, and molecular markers of [...] Read more.

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional Chinese medicinal herb with recognized anti-inflammatory, antioxidant, and immunomodulatory properties. This study evaluated whether dietary supplementation with D. officinale leaf powder could influence bone mass, mechanical strength, and molecular markers of bone metabolism in caged laying hens. A total of 192 healthy 19-week-old Jinghong No. 1 hens were randomly assigned to three dietary groups: a control group fed a basal diet and two treatment groups supplemented with 1200 or 3600 mg/kg of D. officinale leaf powder for 16 weeks. Tibial and femoral bone strength and mineral density did not differ significantly among treatments (p > 0.05). However, tibial breaking strength displayed upward trends in both supplemented groups (p = 0.08), and similar tendencies were observed for femoral bone mineral content and bone density (p = 0.08). At the molecular level, dietary supplementation produced selective changes in gene expression. The low-dose diet significantly increased VEGFA expression (p < 0.05), whereas the high-dose diet resulted in significantly higher TGF-β1 expression (p < 0.05). Several other genes related to bone formation, bone resorption, or cytokine signaling exhibited numerical increases but did not reach statistical significance. These findings indicate that D. officinale leaf powder may modulate bone metabolic processes at the transcriptional level, although these molecular alterations were not accompanied by significant improvements in bone mass. Full article

(This article belongs to the Special Issue Welfare and Behavior of Laying Hens)

20 pages, 3667 KB

Open AccessArticle

Effects of Water-Delivered Probiotics on Performance, Carcass Traits, Immunity, Blood Biochemistry, and Ileal Morphology of Broilers Reared at High Stocking Density Under Warm Ambient Temperature

by Ibrahim Al-Homidan, Abdulla Alsuqayhi, Osama Abou-Emera, Zarroug Ibrahim and Moataz Fathi

Animals 2026, 16(2), 328; https://doi.org/10.3390/ani16020328 - 21 Jan 2026

Abstract

This study investigated the effects of dietary probiotic supplementation and stocking density on the growth performance, carcass traits, immunity, blood biochemical parameters, and ileal histomorphology of broiler chickens. A total of five hundred ten 1-day-old unsexed broiler chicks (Cobb 39) were allocated to [...] Read more.

This study investigated the effects of dietary probiotic supplementation and stocking density on the growth performance, carcass traits, immunity, blood biochemical parameters, and ileal histomorphology of broiler chickens. A total of five hundred ten 1-day-old unsexed broiler chicks (Cobb 39) were allocated to three probiotic levels (0%, 0.1%, 0.2%) and two stocking densities (low vs. high). Results indicated that stocking density significantly influenced body weight from the third week onward, with birds reared under low density showing higher weight and better feed-to-gain ratio. Probiotic supplementation did not significantly affect weekly body weight, feed intake, or mortality, although mortality tended to be lower in probiotic-fed groups. Carcass traits and lymphoid organ indices were largely unaffected by treatments, except for a higher heart percentage in low-density birds. Cell-mediated immunity was enhanced under low stocking density, and probiotic supplementation at 0.2% increased the immune response at 48 h post-challenge. Blood biochemical analysis revealed significant effects of stocking density on total protein, globulin, and triglycerides, while probiotics reduced total lipid and LDL levels. Ileal histomorphology was significantly improved by probiotics, with increased villus height, crypt depth, and villus-to-crypt ratio. Similarly, low stocking density further enhanced these parameters. Overall, probiotic supplementation, particularly at 0.1%, combined with low stocking density, positively influenced gut morphology and immune responses, contributing to improved broiler health and performance. Full article

(This article belongs to the Collection Application of Antibiotic Alternatives in the Poultry Industry)

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14 pages, 2297 KB

Open AccessArticle

Transcriptomics Analysis of Testis Development in Thamnaconus septentrionalis Responding to a Rise in Temperature

by Yan Liu, Xueli Zhang, Wengang Xu, Jiulong Wang, Li Bian, Yanqing Wu, Meng Li and Liming Liu

Animals 2026, 16(2), 327; https://doi.org/10.3390/ani16020327 - 21 Jan 2026

Abstract

Thamnaconus septentrionalis is an emerging commercially important aquaculture species in China, distributed extensively in the Indo-West Pacific Ocean. Recently, because of the seriously declining population and considerable economic potential of this aquaculture fish, increasing attention has been paid to the conservation and development [...] Read more.

Thamnaconus septentrionalis is an emerging commercially important aquaculture species in China, distributed extensively in the Indo-West Pacific Ocean. Recently, because of the seriously declining population and considerable economic potential of this aquaculture fish, increasing attention has been paid to the conservation and development of T. septentrionalis. Artificial fish breeding is essential and has become progressively implemented on local farms in China, which benefits the protection of T. septentrionalis resources and facilitates the development of its fishery industry. Previous studies have demonstrated that temperature could significantly influence ovary development in T. septentrionalis. However, the potential molecular mechanisms underlying the influence of temperature on testis development in T. septentrionalis have been scarcely studied. Thus, this study comprehensively explores the effects of temperature on testis development in T. septentrionalis using histological observation and transcriptomic techniques. Histological and transmission electron microscopy analyses indicated that T. septentrionalis testes, undergoing a rise in temperature, developed from phase III to IV. Transcriptomic analysis identified 315 differentially expressed genes, including 200 upregulated and 115 downregulated genes. Moreover, rising temperatures may enhance testis development by regulating steroid hormone biosynthesis, cellular senescence, and nucleotide metabolism. The upregulation of four genes (hsd11b2, cyp11b, cyp11a, and hsd17b3) involved in the steroid hormone biosynthesis process may significantly contribute to the increased level of testosterone and 11-keto-testosterone. This study is the first to elucidate the potential molecular mechanism involved in T. septentrionalis testis development induced by temperature, offering valuable and novel insights for its artificial breeding and fishery resources conservation. Full article

(This article belongs to the Section Aquatic Animals)

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15 pages, 975 KB

Open AccessArticle

Complications Following Orchiectomy in Stallions in Field Conditions: Descriptive Results and Predictors in a Study of 612 Cases

by Panagiota Tyrnenopoulou, Eugenia Flouraki, Leonidas Folias, Epameinondas Loukopoulos, Alexandros Starras, Panagiotis Chalvatzis, Vassiliki Tsioli, Vasia S. Mavrogianni and George C. Fthenakis

Animals 2026, 16(2), 326; https://doi.org/10.3390/ani16020326 - 21 Jan 2026

Abstract

The objectives of this work were (i) to evaluate the incidence of complications in male horses after orchiectomy performed in the field, i.e., away from a veterinary hospital, (ii) to describe the post-operative complications that occurred in these animals and (iii) to study [...] Read more.

The objectives of this work were (i) to evaluate the incidence of complications in male horses after orchiectomy performed in the field, i.e., away from a veterinary hospital, (ii) to describe the post-operative complications that occurred in these animals and (iii) to study the potential predictors for the development of such complications. This study involved 612 animals, on which orchiectomy was performed. The operative part of the study was carried out by one of three experienced veterinary surgeons. Standard pre-operative procedures were followed. Orchiectomy was performed using one of three principal surgical techniques, open, semi-closed or closed, and hemostasis was achieved by means of one of the various procedures, specifically the use of the Henderson instrument, the use of the Reimer emasculator, the ligation of the testicular artery or combinations thereof. In cases of reported complications, these were verified and identified appropriately. At least one (any) post-operative complication was recorded in 145 horses (23.7%). The most frequently observed complication was scrotal swelling/seroma formation, which was observed in 130 animals (21.2% of all animals; 89.7% of animals with at least one (any) complication). Another six different complications were observed, specifically colic, continued stallion-like behavior, evisceration, funiculitis, hemorrhage and scrotal infection. The median age of horses with complications was significantly older than that of animals with no complications: 11 versus 9 years. Animals in which the open technique was applied developed post-operative complications more frequently (30.1% of animals thus operated); further, complications were observed more frequently in animals on which operations were performed by using the Henderson instrument (84.6% of animals) versus animals on which any of the various other procedures were applied (22.4%). In multivariable analysis, the following predictors emerged for the development of complications: the surgical technique employed, the procedure applied for hemostasis, older animal age, and heavier animal bodyweight. The findings confirm that orchiectomy in stallions, even when performed in field conditions, is, in general, a safe procedure. The identification of predictors suggests that veterinarians should take additional care when planning to operate on animals at higher risk or when using surgical approaches that increase the potential for the development of complications. Full article

(This article belongs to the Special Issue Equine Surgery and Postoperative Management)

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20 pages, 4131 KB

Open AccessArticle

Calcium Nitrate Supplementation Improves Meat Quality in Hu Sheep via Microbial and Transcriptomic Regulation

by Yuanshu Zheng, Chen Zheng, Kang Sun, Huihui Liu, Huiyu Fan, Yi Wang, Xuan Nan, Lijing An, Faming Pan, Xinji Wang, Guoyan Xu and Ting Liu

Animals 2026, 16(2), 325; https://doi.org/10.3390/ani16020325 - 21 Jan 2026

Abstract

Research has demonstrated that incorporating nitrate into animal feed can effectively decrease methane production in ruminants, though its impact on carcass characteristics and meat attributes in Hu sheep requires further investigation. This experiment examined how a dietary inclusion of 3% calcium nitrate (CN) [...] Read more.

Research has demonstrated that incorporating nitrate into animal feed can effectively decrease methane production in ruminants, though its impact on carcass characteristics and meat attributes in Hu sheep requires further investigation. This experiment examined how a dietary inclusion of 3% calcium nitrate (CN) influenced slaughter parameters, meat properties, gut microbial populations, and host gene regulation in Hu sheep. The study involved sixty healthy male Hu sheep aged 120 days with comparable body weights (31.11 ± 3.39 kg), randomly allocated into two groups: a control group receiving standard feed (CON) and a CN-supplemented group. The trial lasted 60 days, including a 15-day adaptation period and a 45-day formal trial period. They were housed individually and fed twice daily (at 8:00 and 18:00). The findings revealed that CN supplementation notably reduced the water loss rate in the longissimus dorsi muscle (LD), elevated meat color brightness, and enhanced the proportion of polyunsaturated fatty acids (PUFA), particularly n-6 PUFA, along with the n-3/n-6 PUFA ratio. Conversely, it reduced the levels of saturated fatty acids such as myristic acid (C14:0) and oleic acid (C18:1n9t). Additionally, the treatment boosted ruminal Ammoniacal nitrogen content and total short-chain fatty acid production, thereby contributing to energy metabolism in the animals. Microbiological examination demonstrated that CN supplementation led to a decrease in Fibrobacterota and Methanobrevibacter populations within the ruminal environment, while promoting the growth of Proteobacteria in the duodenal region. The gene expression profiling of digestive tract tissues showed an increased activity in nitrogen processing genes (including CA4) and oxidative phosphorylation pathways (such as ATP6), indicating an improved metabolic efficiency and acid–base homeostasis in the host animals. These findings demonstrate that CN-enriched diets enhance the carcass characteristics of Hu sheep by modifying intramuscular lipid profiles through gastrointestinal microbial community restructuring and metabolic pathway adjustments. Such modifications affect energy utilization and acid–base equilibrium, ultimately impacting muscle characteristics and adipose tissue distribution, presenting viable approaches for eco-friendly livestock farming practices. Full article

(This article belongs to the Special Issue Advanced Welfare-Oriented, Efficient, and High-Quality Ruminant Production: Mechanisms and Practices)

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21 pages, 3126 KB

Open AccessArticle

Effect of Coated Inorganic Micro-Minerals on Growth, Mineral Retention, and Intestinal Health in Juvenile American Eels Under a Commercial RAS

by Xiaozhao Han, Deying Ma, Yichuang Xu and Shaowei Zhai

Animals 2026, 16(2), 324; https://doi.org/10.3390/ani16020324 - 21 Jan 2026

Abstract

Micro-minerals are essential for fish, but traditional inorganic micro-minerals (IMM) have low bioavailability. This study evaluated coated inorganic micro-minerals (CIMM) in juvenile American eels under commercial recirculating aquaculture system (RAS) conditions. Three experimental groups (n = 3 tanks per group, stocking density: [...] Read more.

Micro-minerals are essential for fish, but traditional inorganic micro-minerals (IMM) have low bioavailability. This study evaluated coated inorganic micro-minerals (CIMM) in juvenile American eels under commercial recirculating aquaculture system (RAS) conditions. Three experimental groups (n = 3 tanks per group, stocking density: 138 fish/m³) were fed basal diets supplemented for 56 days with: 1000 mg/kg IMM (IMM group, providing Cu 7, Fe 200, Mn 30, Zn 70, I 1.6, Se 0.4, and Co 1.2 mg/kg diet), 1000 mg/kg CIMM (CIMM group I), or 500 mg/kg CIMM (CIMM group II). Compared to the IMM group, the CIMM group I demonstrated significantly enhanced growth performance, with the specific growth rate increasing by approximately 31.14%, higher whole-body content and retention of minerals (Ca, P, Cu, Fe, Mn, Zn), and superior intestinal health, as reflected by significantly increased activities of digestive enzymes (amylase and lipase), enhanced antioxidant capacity (elevated SOD and CAT, reduced MDA), and improved morphology (villi length and muscular thickness), an altered intestinal microbiota (increased relative abundance of Firmicutes and reduced relative abundance of Proteobacteria), and significant metabolomic alterations in purine metabolism and linoleic acid metabolism. The CIMM group II maintained growth performance, with no significant difference in WGR and SGR compared to the IMM group, while still showing significant improvements in feed intake and mineral retention (P, Cu, Fe, Zn), and antioxidant capacity. Collectively, this study not only confirms the efficacy of CIMM in commercial RAS but also reveals that the supplementation level previously shown to be effective in the laboratory (50% CIMM) is insufficient under commercial farming conditions, implying that the dietary micro-mineral requirements for juvenile American eels in commercial RAS may be higher than those established in laboratory settings. Full article

(This article belongs to the Special Issue Nutrition and Health of Aquatic Animals)

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16 pages, 395 KB

Open AccessReview

Haptic Signals as a Communication Tool Between Handlers and Dogs: Review of a New Field

by Hillary Jean-Joseph and Dalila Bovet

Animals 2026, 16(2), 323; https://doi.org/10.3390/ani16020323 - 21 Jan 2026

Abstract

Developing new haptic communication tools to enhance communication between dogs and their handlers during field operations has garnered interest in recent years. It is a promising field that could ameliorate dog–handler interactions in the field while addressing practical challenges, such as the need [...] Read more.

Developing new haptic communication tools to enhance communication between dogs and their handlers during field operations has garnered interest in recent years. It is a promising field that could ameliorate dog–handler interactions in the field while addressing practical challenges, such as the need for discrete communication during operations. When extended to the public, such technology could improve communication with impaired dogs. With this review, we aim to (1) give an overview of dogs’ understanding and discrimination of haptic signals, (2) highlight the need to investigate the possible impact of such tools on dogs’ welfare, as well as (3) point out current caveats and future research directions. Full article

(This article belongs to the Special Issue Beyond the Home: Exploring Human–Animal Relationships in Veterinary, Agricultural, and Workplace Contexts)

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13 pages, 739 KB

Open AccessArticle

Electrophoretic Profile of Urinary Proteins in Goats During the Peripartum Period

by Berihu Gebrekidan Teklehaymanot, Marilena Bolcato, Gloria Isani, Angelica Lembo, Tolulope Grace Ogundipe, Giulia Ballotta, Francesco Dondi, Arcangelo Gentile and Sabrina Fasoli

Animals 2026, 16(2), 322; https://doi.org/10.3390/ani16020322 - 21 Jan 2026

Abstract

Background: Urinary proteins may reflect physiological changes occurring during the periparturient period, but reference data for goats are still lacking. This study investigated urinary protein patterns around parturition to help fill this gap and generate baseline information. Methods: Ten pregnant Alpine goats were [...] Read more.

Background: Urinary proteins may reflect physiological changes occurring during the periparturient period, but reference data for goats are still lacking. This study investigated urinary protein patterns around parturition to help fill this gap and generate baseline information. Methods: Ten pregnant Alpine goats were sampled by spontaneous voiding 22 ± 3 days before delivery (T0), 7 days postpartum (T7), and 30 days postpartum (T30). Physical and chemical urine analyses were performed, and urinary proteins were separated using one-dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Statistical tests (Shapiro–Wilk, repeated-measures ANOVA, or Friedman) were applied to evaluate differences among time points. Results: Significant temporal changes were observed: urine pH decreased at T30, the urine protein-to-creatinine ratio increased at T7 and T30, and urinary creatinine concentration was highest at T0. Most samples showed common protein bands at approximately 80, 70, 62, 50, 37, 29, 25, 22, and below 13 kDa, with the 62, 50, and <13 kDa bands present in all samples. Bands between 18 and 64 kDa and above 60 kDa appeared only in some samples. Protein bands between 23 and 42 kDa were more frequent at T0, suggesting immune-related variations associated with pregnancy. Conclusions: This study provides the first description of urinary protein electrophoretic profiles in goats during the periparturient period and highlights measurable changes across time. These findings offer a starting point for developing future research and may contribute to establishing reference parameters for clinical and physiological monitoring in goats. Full article

(This article belongs to the Section Small Ruminants)

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18 pages, 266 KB

Open AccessArticle

Associations Between Adoption Discounts, Length-of-Stay, and Adoption Rates of Dogs in an Open-Admission Municipal Animal Shelter in NSW, Australia

by Tianyang Qiu, Simone J. Maher, Evelyn Hall and Mark E. Westman

Animals 2026, 16(2), 321; https://doi.org/10.3390/ani16020321 - 21 Jan 2026

Abstract

This study explored possible associations between adoption discounts, length-of-stay (LOS), and adoption rates for dogs at a municipal (council) shelter in New South Wales (NSW), Australia, over a one-year period (4 April 2023–3 April 2024). Data from 479 rehomed dogs and eight temporary [...] Read more.

This study explored possible associations between adoption discounts, length-of-stay (LOS), and adoption rates for dogs at a municipal (council) shelter in New South Wales (NSW), Australia, over a one-year period (4 April 2023–3 April 2024). Data from 479 rehomed dogs and eight temporary promotional campaigns were analysed, considering the following factors: discount levels applied, breed group, body size, age group, coat colour, intake method (stray, privately surrendered, or seized), and return-to-shelter history after adoption. Dogs with ≥75% discount and 0–50% discount had a longer LOS compared to those without a discount (p < 0.001), likely because many discounted dogs already had a prolonged LOS prior to the campaign’s commencement. Other important LOS predictors included breed group (p < 0.001), body size (p < 0.001), age group (p = 0.004), and intake method (p < 0.001). Gundogs/hounds/terriers (purebred), and toy/non-sporting groups (both purebred and crossbred), small-sized dogs, seniors, puppies, and privately surrendered dogs had significantly lower LOS compared to their counterparts. However, when daily adoption rates were examined, temporary price-discounting campaigns resulted in substantially increased rehoming rates. In particular, Flash Sales (≤48 h) increased daily adoptions by 204% compared to non-campaign periods. One Flash Sale event resulted in higher daily adoption rates, but also significantly higher return rates compared to other temporary campaigns, highlighting a possible risk of impulse adoptions and necessitating future work with adopters to identify potentially problematic decision-making. Shelters should be aware that, on an individual level, factors other than price can be more important for potential adopters. On a broader level, temporary campaigns involving a reduced adoption price can increase overall adoption rates and therefore should be considered as part of any marketing exposure strategy for animal shelters. Full article

(This article belongs to the Section Animal Welfare)

11 pages, 6494 KB

Open AccessArticle

Integrating Beach Monitoring and Satellite Telemetry to Estimate Loggerhead Clutch Frequency in Brazil

by Paulo Hunold Lara, Gustavo Stahelin, Maria Ângela Marcovaldi, Alexsandro Santana dos Santos, Yonat Swimmer and Milagros López Mendilaharsu

Animals 2026, 16(2), 320; https://doi.org/10.3390/ani16020320 - 21 Jan 2026

Abstract

Accurate clutch-frequency estimates are essential for assessing population abundance and reproductive output in sea turtles. Traditional nighttime beach-monitoring approaches, however, often underestimate clutch frequency by missing nesting events occurring outside patrolled beaches. Here, we integrated long-term beach monitoring (2009–2016) with satellite telemetry to [...] Read more.

Accurate clutch-frequency estimates are essential for assessing population abundance and reproductive output in sea turtles. Traditional nighttime beach-monitoring approaches, however, often underestimate clutch frequency by missing nesting events occurring outside patrolled beaches. Here, we integrated long-term beach monitoring (2009–2016) with satellite telemetry to estimate the clutch frequency of loggerhead turtles (Caretta caretta) nesting at Praia do Forte, Bahia, Brazil. A total of 593 females were identified along a 5 km monitored beach segment, and transient individuals represented 42.4% ± 3.9 SD of seasonal records. A 2-year remigration interval was the most frequent. The observed clutch frequency (OCF) averaged 3.1 ± 1.2 SD clutches per female, while the estimated clutch frequency based on beach monitoring alone (ECF_BM) averaged 3.9 ± 1.5 SD. For the subset of satellite-tracked females (n = 12), integration of residency length derived from telemetry increased the estimate to 5.6 ± 0.7 SD clutches per female (ECF_BMST). Statistical comparisons confirmed significant differences among estimation methods. These findings align with previous studies, demonstrating that clutch frequency is substantially underestimated when relying solely on beach monitoring. Incorporating satellite telemetry, therefore, provides a more accurate assessment of reproductive output and has important implications for population modelling and the conservation of loggerhead turtles in Brazil. Full article

(This article belongs to the Special Issue Sea Turtle Nesting Behavior and Habitat Conservation)

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14 pages, 637 KB

Open AccessArticle

Doppler Waveform Alterations of the Supratesticular Artery and Associated Semen Biomarkers in Infertile Male Dromedary Camels

by Derar Derar, Ahmed Ali, Fahad A. Alshanbari and Mohammed H. Elzagafi

Animals 2026, 16(2), 319; https://doi.org/10.3390/ani16020319 - 20 Jan 2026

Abstract

Male infertility in dromedary camels lacks objective diagnostic tools. This study evaluated the combined diagnostic value of testicular Doppler ultrasonography and semen biomarkers in 68 infertile (azoospermic, n = 21; oligozoospemic, n = 47) and 9 fertile male camels. All animals underwent a [...] Read more.

Male infertility in dromedary camels lacks objective diagnostic tools. This study evaluated the combined diagnostic value of testicular Doppler ultrasonography and semen biomarkers in 68 infertile (azoospermic, n = 21; oligozoospemic, n = 47) and 9 fertile male camels. All animals underwent a breeding soundness evaluation; computer-assisted semen analysis; color Doppler of the supratesticular artery; and a seminal plasma assessment for semenogelin I (SEM I), semenogelin II (SEM II), extracellular matrix protein 1 (ECM1), and testis-expressed protein 101 (TEX101). Infertile camels showed significantly impaired semen quality (p < 0.001). All four biomarkers were significantly lower in the infertile groups than controls (p = 0.001). Doppler indices indicated impaired testicular perfusion, with higher resistive and pulsatility indices (p = 0.003; p = 0.009) and lower velocity parameters (p < 0.001) in infertile animals. Biomarkers were strongly intercorrelated and negatively correlated with Doppler indices. ECM1 was the only significant predictor of infertility from the regression analysis (p = 0.031). Among the oligozoospemic camels stratified by motility, the >50% motility group had significantly higher SEM I and SEM II concentrations (p < 0.002). Integrating Doppler ultrasonography with biomarker profiling provides complementary diagnostic indicators for male camel infertility. Full article

(This article belongs to the Section Animal Reproduction)

18 pages, 1429 KB

Open AccessArticle

Urban–Rural Differences in Preferences for Environmentally Friendly Farming from the Perspectives of Oriental White Stork Conservation

by Liyao Zhang, Zhen Miao, Yinglin Wang, Xingchun Li, Xuehong Zhou and Yujuan Gao

Animals 2026, 16(2), 318; https://doi.org/10.3390/ani16020318 - 20 Jan 2026

Abstract

Expanded and intensified agriculture is a major driver of habitat loss for endangered species such as the Oriental White Stork (Ciconia boyciana), making wildlife-friendly farming an increasingly important approach for reconciling biodiversity conservation with agricultural development. Building on a 2018 feasibility [...] Read more.

Expanded and intensified agriculture is a major driver of habitat loss for endangered species such as the Oriental White Stork (Ciconia boyciana), making wildlife-friendly farming an increasingly important approach for reconciling biodiversity conservation with agricultural development. Building on a 2018 feasibility study in the Sanjiang Plain, this research employs a choice experiment to examine how preferences for Oriental White Stork-friendly farming have evolved among urban consumers and residents of stork habitats under expanding green consumption and increasing experience with environmentally friendly farming. The results reveal pronounced preference heterogeneity and persistent cognitive separation between wildlife conservation and agricultural production, particularly among urban consumers, despite a stable group being willing to pay a premium for stork-friendly products. Rural residents’ decisions remain largely economically driven, though younger farmers with prior experience in environmentally friendly practices show more positive attitudes. Significant urban–rural differences suggest policy complementarities, whereby price-oriented incentives may encourage price-sensitive farmers to adopt green agriculture, while intrinsically motivated farmers require support through an Oriental White Stork-oriented value chain. Overall, the findings demonstrate that Wildlife-Friendly Farming cannot be effectively promoted through a one-size-fits-all approach; instead, stratified, group-specific policy and market mechanisms are essential for aligning producer incentives with consumer demand and supporting the long-term viability of biodiversity-friendly agricultural systems. Full article

(This article belongs to the Section Wildlife)

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17 pages, 3213 KB

Open AccessArticle

Analysis of Migration and Adaptive Evolution in Tibetan Sheep Populations

by Wentao Zhang, Chao Yuan, Tingting Guo, Bowen Chen, Fan Wang, Jianbin Liu and Zengkui Lu

Animals 2026, 16(2), 317; https://doi.org/10.3390/ani16020317 - 20 Jan 2026

Abstract

The genetic basis for Tibetan sheep adaptation to different high-altitude environments remains unknown. This study conducted whole-genome resequencing on 80 Tibetan sheep individuals from four major distribution areas on the Qinghai–Tibet Plateau. Based on the high-quality single-nucleotide polymorphisms (SNPs) obtained, an analysis of [...] Read more.

The genetic basis for Tibetan sheep adaptation to different high-altitude environments remains unknown. This study conducted whole-genome resequencing on 80 Tibetan sheep individuals from four major distribution areas on the Qinghai–Tibet Plateau. Based on the high-quality single-nucleotide polymorphisms (SNPs) obtained, an analysis of population-level genomic selection signals was performed. Population genomic analysis revealed that Tibetan sheep distributed across China originated in northern China but showed evidence of gene flow from South Asian sheep. Between populations from extremely high-altitude and mid-altitude regions, selection analyses identified five strongly positive selected genes (HIF1AN [Hypoxia Inducible Factor 1 Alpha Subunit Inhibitor], HBE1 [Hemoglobin Subunit Epsilon 1], HBE2 [Hemoglobin Subunit Epsilon 2], TNFAIP3 [TNF Alpha Induced Protein 3], RAD50 [RAD50 Double Strand Break Repair Protein]). These genes are associated with adaptation to hypoxia and intense UV radiation in high-altitude environments. Selection analyses between populations from extremely high-altitude and mid-altitude regions identified five strongly selected genes (HIF1AN [Hypoxia Inducible Factor 1 Alpha Subunit Inhibitor], HBE1 [Hemoglobin Subunit Epsilon 1], HBE2 [Hemoglobin Subunit Epsilon 2], TNFAIP3 [TNF Alpha Induced Protein 3], RAD50 [RAD50 Double Strand Break Repair Protein]) associated with hypoxia and intense UV radiation in high-altitude environments. Comparative genomic analyses of populations in cold and arid environments identified several candidate genes related to energy and water homeostasis, as well as hair development (TP53 [Tumor Protein P53], ATG101 [Autophagy Related 101], ATP12A [ATPase H+/K+ Transporting Non-Gastric Alpha2 Subunit], KRT80 [Keratin 80], KRT7 [Keratin 7]). Additionally, Tibetan sheep in the high-altitude arid deserts exhibit stronger adaptive selection for energy homeostasis and water utilization; meanwhile, the HIF-1 [Hypoxia Inducible Factor 1] signaling pathway helps counteract oxidative stress induced by extreme water scarcity in the plateau environment. Our study supports the hypothesis that Tibetan sheep originated in northern China and identifies distinct adaptive features in the Tibetan sheep genome corresponding to their habitats. Full article

(This article belongs to the Special Issue Advanced Welfare-Oriented, Efficient, and High-Quality Ruminant Production: Mechanisms and Practices)

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21 pages, 3309 KB

Open AccessArticle

Microcystin-LR-Induced Oxidative Stress, Transcriptome Changes, Intestinal Microbiota, and Histopathology in Rana chensinensis Tadpoles

by You Wang, Bingjie Wang, Zhuolin He, Jiaxin Chen, Chenyang Liu, Zhanqi Wang, Muhammad Irfan and Lixia Zhang

Animals 2026, 16(2), 316; https://doi.org/10.3390/ani16020316 - 20 Jan 2026

Abstract

Microcystin-LR (MC-LR), produced by Cyanobacteria, is being detected in many types of waters, posing a universal threat to aquatic animals. However, there have been few comprehensive endpoints assessed, including oxidative stress, transcriptome changes, intestinal microbiota, and histopathology, in anurans exposed to MC-LR. In [...] Read more.

Microcystin-LR (MC-LR), produced by Cyanobacteria, is being detected in many types of waters, posing a universal threat to aquatic animals. However, there have been few comprehensive endpoints assessed, including oxidative stress, transcriptome changes, intestinal microbiota, and histopathology, in anurans exposed to MC-LR. In this study, all these effects of MC-LR on Chinese brown frog (Rana chensinensis David, 1875) tadpoles were investigated by exposing the tadpoles to MC-LR at different concentrations (0, 0.1, 1.0, 5.0, and 10.0 μg/L) for 7 days. Our results revealed that treatment of tadpoles with the high MC-LR dosage (10.0 μg/L) induced a significant increase in malondialdehyde (MDA) content and decreases in superoxide dismutase (SOD) activity, glutathione peroxidase (GPx) activity, and total antioxidant capacity (TAC). RNA-seq analysis of the liver showed that the number of differentially expressed genes (DEGs) was 2361 under lower MC-LR stress (1.0 μg/L), while the number of DEGs increased to 3185 under higher MC-LR stress (10.0 μg/L). Gene Ontology analysis showed that several biological processes and molecular functions related to digestion were enriched in both MC-LR treated groups, such as digestion, serine-type endopeptidase activity, and serine-type peptidase activity. KEGG enrichment analysis also indicated that the digestion for pancreatic secretion, protein digestion and absorption, and fat digestion and absorption pathways were significantly enriched in the treatment groups. Additionally, the bacterial richness was elevated by MC-LR exposure. At the phylum level, treatment with MC-LR changed the relative abundances of Desulfobacterota, Fusobacteriota, and Actinobacteriota. At the genus level, MC-LR caused significant alterations in the abundances of 23 genera. Furthermore, examination of sections obtained from the livers and intestines of tadpoles in the treatment groups showed damaged histological structure. The knowledge from this study will have potential value for understanding the mechanisms related to MC-LR toxicity in anurans. Full article

(This article belongs to the Section Aquatic Animals)

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17 pages, 4757 KB

Open AccessArticle

Antiviral Activity of Eugenol Against Chinese Rice-Field Eel Rhabdovirus in Monopterus albus

by Jingwen Jiang, Mingyang Xue, Wenzhi Liu, Yong Zhou, Yiqun Li and Yuding Fan

Animals 2026, 16(2), 315; https://doi.org/10.3390/ani16020315 - 20 Jan 2026

Abstract

Chinese rice-field eel rhabdovirus (CrERV) is a serious epidemic pathogen of Chinese rice-field eel and causes severe economic losses to aquaculture. However, there are no commercial drugs presently available to control CrERV infection. Eugenol is a bioactive compound extracted from clove plants and [...] Read more.

Chinese rice-field eel rhabdovirus (CrERV) is a serious epidemic pathogen of Chinese rice-field eel and causes severe economic losses to aquaculture. However, there are no commercial drugs presently available to control CrERV infection. Eugenol is a bioactive compound extracted from clove plants and exhibits potential antiviral activity. In the study, the antiviral activity of eugenol against CrERV was investigated in Chinese rice-field eel (Monopterus albus). Eugenol reached the highest inhibition rate of 96.6% at 40 mg/L in Chinese rice-field eel kidney cells (CrEK). Notably, eugenol exhibits antiviral activity by directly targeting CrERV and additionally confers prophylactic effects against infection via its action on CrEK cells. The results of exploring the viral invasion cycle demonstrated that eugenol primarily exerted its antiviral effect during the middle stage and late stage (12 h and 24 h) of viral infection. In addition, eugenol inhibited CrERV-induced apoptosis of CrEK cells, maintained mitochondrial membrane potential levels, maintained physiological cellular morphology and structure, and protected cells from loss of cellular morphology, formation of apoptotic vesicles, and cell fragmentation. For the in vivo study, eugenol increased the survival rate of CrERV-infected rice-field eel by 56% and 48%, in prevention experiments and treatment experiments, respectively. Concurrently, eugenol significantly reduced viral loads and induced the upregulation of anti-inflammatory and antioxidant genes, indicating its potential for immunoregulation. In summary, eugenol holds potential for both preventing and treating CrERV infections in the aquaculture context. Full article

(This article belongs to the Section Aquatic Animals)

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