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1.
Front Vet Sci ; 11: 1367810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086766

RESUMO

Bovine leukemia virus (BLV) establishes a lifelong persistent infection in dairy cattle. White blood cell count (WBC) is correlated with proviral load in the blood and milk of BLV-infected cattle, and testing WBC can be used to assess both BLV infectiousness levels and risk of BLV transmission from different types of infected animals. The objective of the study was to compare effective transmission rates (ß) and the basic reproduction ratio (R o) among two types of BLV-infected dairy cows in Chile: those affected with persistent lymphocytosis (PL) vs. aleukemic (AL).The estimated (ß) coefficient was higher in PL cattle [1.1; 95% Confidence interval (CI) (-1.6, 3.8)], compared to AL cattle (-3.1; 95% CI = -3.7, -2.5). In addition, the R o was higher in PL cattle (60.4; 95% CI = 3.5; 820.6), compared to AL cattle (1.5; 95% CI = 0.7, 3.1). The ratio between PL/AL expected rate of cases was 73.9. The estimated effective transmission rate and the Ro were higher in PL cattle compared to AL cattle. The WBC test is a convenient alternative that can be considered for risk identification and risk management of BLV infection in dairy herds; particularly in livestock regions where laboratory capacity is limited (e.g., use of PCR or gene sequencing techniques) and/or molecular tests are not cost-effective. Therefore, when prevalence of infection is high, the removal of PL cattle should be engaged to control BLV within-herds.

2.
Reprod Domest Anim ; 59(8): e14692, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39091039

RESUMO

Anti-Müllerian hormone (AMH) is a hormone produced by growing preantral and antral follicles of the ovary. AMH is accepted as an important biomarker for fertility and superovulation parameters in livestock species. This study aimed to evaluate changes in serum AMH level in the oestrous cycle, repeatability of AMH, the effect of age on serum AMH level and the effects of AMH on litter size in Romanov sheep. In the study, a total of 36 Romanov sheep were used as animal material. First blood samples (0th day) were collected from 36 ewes to evaluate AMH and progesterone levels. Second blood samples were collected randomly from 20 ewes 9 days after first sampling to compare AMH levels at two different periods of the oestrous cycle in Romanov ewes. The ewes were categorized into three groups as low, medium and high AMH based on their first AMH levels. Results indicated that serum AMH level did not change during the oestrous and dioestrous phases of the oestrous cycle and two random time points of the oestrous cycle (p > .05). Pearson correlation analysis revealed that there is a high (r = .95) and significant (p < .001) correlation between AMH levels at the 0th (AMH-1) and 9th (AMH-2) days. The effect of AMH level on litter size was found to be significant. Litter size was significantly higher in the high AMH group than in the low AMH group (p < .05). In addition, the age of ewes did not affect serum AMH levels (p > .05). ROC analysis indicates that AMH cut-off value >320 pg/mL with 70% sensitivity and 100% specificity can be used for litter size in Romanov ewes. In conclusion, AMH is highly repeatable and its serum AMH level did not change during the oestrous cycle in Romanov sheep. In addition, AMH affects litter size and can be reliably used as a marker for litter size in Romanov sheep.


Assuntos
Hormônio Antimülleriano , Biomarcadores , Tamanho da Ninhada de Vivíparos , Progesterona , Animais , Hormônio Antimülleriano/sangue , Feminino , Biomarcadores/sangue , Progesterona/sangue , Ciclo Estral/sangue , Ciclo Estral/fisiologia , Carneiro Doméstico/fisiologia , Ovinos/fisiologia
3.
Am J Epidemiol ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39086096

RESUMO

BACKGROUND: Yearly bronchiolitis and influenza-like illness epidemics in France often involve high morbidity and mortality, which severely impacts healthcare. Epidemics are declared by the French National Institute of Public Health based on syndromic surveillance of primary care and emergency departments (ED), using statistics-based alarms. Although the effective reproduction number (Rt) is used to monitor the dynamics of epidemics, it has never been used as an early warning tool for bronchiolitis or influenza-like illness epidemics in France.We assessed whether Rt is useful for detecting seasonal epidemics by comparing it to the tool currently used (MASS) by epidemiologists to declare epidemic phases. METHODS: We used anonymized ED syndromic data from the Île-de-France region in France from 2010 to 2022. We estimated Rt and compared the indication of accelerated transmission (Rt >1) to the MASS epidemic alarm time points. We computed the difference between those two time points, time to epidemic peak, and the daily cases documented at first indication and peak. RESULTS: Rt provided alarms for influenza-like illness and bronchiolitis epidemics that were, respectively, 6 days (IQR[4;8]) and 64 days (IQR[52;80]) - in median - earlier than the alarms provided by MASS. CONCLUSION: Rt detected earlier signals of bronchiolitis and influenza-like illness epidemics. Using this early-warning indicator in combination with others to declare an annual epidemic could provide opportunities to improve healthcare system readiness.

4.
Ecol Evol ; 14(8): e11464, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39091335

RESUMO

Diatoms are single-celled organisms that contribute approximately 20% of the global primary production and play a crucial role in biogeochemical cycles and trophic chains. Despite their ecological importance, our knowledge of microevolution is limited. We developed a model using the SLiM evolutionary framework to address this knowledge gap. As a reference, we used the diatom Pseudo-nitzschia multistriata, which has been extensively studied in the Gulf of Naples. Our model recapitulates what we observe in natural populations, with microevolutionary processes that occur annually during a three-stage bloom phase. Interestingly, we found that non-bloom phases allow the population to maintain sex-generated diversity produced during blooms. This finding suggests that non-bloom phases are critical to counteract bloom-related pressures and mitigate genetic divergence at the species level. Moreover, our model showed that despite the consistent genetic differentiation during bloom phases, the population tends to return to pre-bloom states. While our model is limited to neutral dynamics, our study provides valuable insights into diatoms' microevolution, paving the way to explore the ecological implications of the life history dynamics of these organisms.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39089445

RESUMO

Temperature is a preeminent factor in the regulation of fish reproduction and hinders gonadal development beyond a specific threshold. To comprehend the molecular mechanism responsible for reproductive suppression at different temperature, expression of the genes encoding kisspeptin (kiss2), gonadotropin-releasing hormone (gnrh1) and their receptors (gpr54, gnrh1r) in the brain, and the gonadotropin (GTH) subunits (fshb and lhb) in the pituitary were studied in juvenile Nile tilapia (Oreochromis niloticus) along with gonadal histology. Fish were acclimatized to three distinct temperatures, including 31 °C, 34 °C and 37 °C for 14 days. The mRNA levels of kiss2, gpr54, gnrh1, and gnrh1r were significantly decreased at 37 °C compared to 31 °C and 34 °C in the both sexes. In parallel, the expression level of fshb in the both sexes and lhb in the female were significantly lower at 37 °C in the pituitary. Histologically, the gonads of both sexes had normal growth of gametes at control temperature (31 °C), whereas the spermatogenesis and oocyte maturation were slowed down and atretic oocytes were found in the ovary at 37 °C acclimation temperature. Taken together, the results imply that elevated temperature beyond the specific threshold may have a negative impact on reproduction by suppressing the gene expressions of kisspeptin/GnRH1/GTH system and eventually restrains normal growth and maturation of gametes in the both sexes of Nile tilapia.

6.
Gene ; : 148795, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39097207

RESUMO

COVID-19 vaccines have been illustrated to lessen the growth of sickness caused by the virus effectively. In any case, inoculation has consistently been controversial, with differing opinions and viewpoints. This has compelled some individuals to decide against receiving the vaccine. These divergent viewpoints have had a trivial impact on the epidemic's dynamics and the disease's development. In response to vaccinated individuals still falling ill, many countries have implemented booster vaccines to protect further. In this specific investigation, a mathematical model composed of seven compartments is employed to examine the effectiveness of a booster dose in preventing and treating the transmission of COVID-19. The principles of mathematics are employed to analyse and investigate the dynamics of the disease. Using a qualitative prototype analysis, we acquired valuable insights into its effectiveness. One essential aspect is the basic reproduction number, a critical determinant of the disease's spread. This calculation is determined by studying the system's equilibrium and evaluating its stability. Furthermore, we examined the balance from a local and global viewpoint, considering the possibility of bifurcation and the model's reproductive number sensitivity index. Through numerical simulations, we have visually illustrated the analytical findings outlined in this research paper and presented a thorough examination of the efficacy of booster shots as a preventive and therapeutic measure in the spread dynamics of COVID-19.

7.
Arch Physiol Biochem ; : 1-9, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092983

RESUMO

OBJECTIVE: To investigate the comprehensive effects of daily chronic asprosin administration on various pubertal and reproductive parameters in female rats. This study aims to elucidate the role of asprosin in regulating the onset of puberty and its influence on hormonal profiles and ovarian histology. METHODS: Asprosin was administered intraperitoneally (i.p.) at a dose of 500 ng/kg daily for eight weeks. Hormonal assays and histological analyses were performed to evaluate the effects of asprosin on the onset of puberty and reproductive function. RESULTS: Daily chronic administration of asprosin accelerated the onset of the first oestrus. Hormonal assays revealed significant elevations in serum levels of Follicle-Stimulating Hormone (FSH) and Oestradiol (E2), while Inhibin B levels decreased. Histological evaluations demonstrated an increased number of primary and secondary follicles in ovarian tissue, without affecting primordial follicle counts or reproductive organ weights. CONCLUSIONS: Role of adipokines in regulating puberty and reproductive function has increasingly gained recognition. This study aimed to provide the first comprehensive examination of the effects of daily chronic asprosin administration on pubertal and reproductive parameters in female rats. Utilising hormonal assays and histological analyses, asprosin was administered intraperitoneally (i.p.) at a dose of 500 ng/kg, daily, for eight weeks. Our findings revealed that daily chronic administration of asprosin accelerated the onset of the first oestrus. Hormonal assays showed significant elevations in serum levels of Follicle-Stimulating Hormone (FSH) and Oestradiol (E2), while Inhibin B levels decreased. Histological evaluations demonstrated an increased number of primary and secondary follicles in ovarian tissue, without affecting primordial follicle counts or reproductive organ weights. These results provide new insights into asprosin's role in advancing the age of first oestrus and modulating hormonal profiles, thereby offering potential benefits to the female reproductive system.

8.
Mult Scler Relat Disord ; 90: 105789, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39096667

RESUMO

BACKGROUND: Women have a higher risk of developing multiple sclerosis (MS) than men. The natural reproductive period from menarche to menopause corresponds to the period of active inflammatory disease in MS. Mothers and pregnant women with MS need information about how their disease may affect pregnancy and breastfeeding. AIM: The aim was to explore the reproductive factors in an MS-diagnosed population and to identify ways to support patients and their decision-making process. METHODS: We conducted a cross-sectional, Web-based survey of women living with MS in Asturias (Spain) using a community-based participatory approach. FINDINGS: Early menarche may predict the onset of MS. Pregnancy improves the general health of patients and reduces the number of relapses. Breastfeeding is often not practised and may cause concern in women. MS does not affect the age of menopause, but it can worsen symptoms. However, menopause does not increase the number of MS relapses. CONCLUSIONS: MS is increasingly diagnosed at an earlier age, which increases the number of women who become pregnant after being diagnosed with MS. The decrease in MS relapses during pregnancy and the increase during the postpartum period are consistent with previous reports. Women who choose to breastfeed are in the minority due to treatment incompatibility, although some currently used treatments are compatible with breastfeeding. However, there is a lack of information on this which should be investigated.

9.
Andrology ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092868

RESUMO

BACKGROUND: Sleep deprivation (SD) can cause damage to the male reproductive system. However, the duration required for such damage and the specific sequence and severity of damage to the testis and epididymis remain unclear. OBJECTIVE: To investigate the effects of different durations of SD on different parts of the testis and epididymis caput, corpus, and cauda. METHODS: Adult ICR mice were randomly assigned to five groups: the SD group (SD for 18 h/day for 1, 2, 3, or 4 weeks), the SD + Vit E group (supplemented with Vit E 50 mg/kg/d during 4 weeks of SD, the SD+NS group (saline supplementation during 4 weeks of SD), the SD + RS group (5 weeks of recovery sleep after 4 weeks of SD), and a normal sleep control (Ctrl) group. Following the interventions, sperm parameters, testicular and epididymal histopathology, inflammatory response, and oxidative stress markers were compared between the groups. RESULTS: Compared to the Ctrl group, the SD group showed a decrease in sperm motility and concentration from SD 2 W and SD 3 W, respectively. Decreases in sperm concentration and motility were more pronounced in the cauda compared to the caput and corpus. Pathological damage was less severe in the epididymis caput than in the corpus and cauda. After 4 weeks of SD, inflammation and oxidative stress increased in both testes and epididymis. Both sleep recovery and vitamin E supplementation showed significant improvements, though they did not fully reach the level of the Ctrl group. CONCLUSION: Chronic SD for more than 2 weeks causes varying degrees of damage to the testis, epididymis caput, corpus, and cauda in male mice. This damage is not fully reversible after 5 weeks of sleep recovery and antioxidant stress treatment. These findings help us to identify and prevent SD damage to the male reproduction at an early stage.

10.
Andrology ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092870

RESUMO

Novel male contraceptives have been in development for well over half a century, and despite a robust predicted global market for new methods, funding for research and development has been extremely limited. While the pharmaceutical industry previously supported male contraceptive research and development, industry partners are only spectators in the current space, awaiting a product that has been de-risked by the public sector before re-entering the field. Current male contraceptive development efforts are thus primarily funded by nonprofit, non-governmental, and government agencies who also act as the primary advocates for the field. Specific organizations include the International Consortium on Male Contraception, the Population Council, the Male Contraceptive Initiative, the World Health Organization, and the US National Institutes of Health. The funding provided by these public agencies, alongside their social and policy-based advocacy efforts such as market research, public education, and calls to action have kept the male contraceptive product development space afloat, resulting in a pipeline of potential products advancing towards market approval. However, as these products mature into more expensive clinical stages of development, they continue to face significant funding challenges, which many programs may not overcome. To fully realize the benefits of novel male contraceptive options, it is incumbent on philanthropic entities, impact investors, venture capital, and/or the pharmaceutical sector to provide significant and timely support for male contraceptive research and development.

11.
Expert Rev Mol Diagn ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107971

RESUMO

INTRODUCTION: Preimplantation Genetic Testing (PGT) is a cutting-edge test used to detect genetic abnormalities in embryos fertilized through Medically Assisted Reproduction (MAR). PGT aims to ensure that embryos selected for transfer are free of specific genetic conditions or chromosome abnormalities, thereby reducing chances for unsuccessful MAR cycles, complicated pregnancies, and genetic diseases in future children. AREAS COVERED: In PGT, genetics, embryology and technology progress and evolve together. Biological and technological limitations are described and addressed to highlight complexity and knowledge constraints and draw attention to concerns regarding safety of procedures, clinical validity, and utility, extent of applications and overall ethical implications for future families and society. EXPERT OPINION: Understanding the genetic basis of diseases along with advanced technologies applied in embryology and genetics contribute to faster, cost-effective, and more efficient PGT. Next Generation Sequencing-based techniques, enhanced by improved bioinformatics, are expected to upgrade diagnostic accuracy. Complicating findings such as mosaicism, mt-DNA variants, variants of unknown significance, or variants related to late-onset or polygenic diseases will however need further appraisal. Emphasis on monitoring such emerging data is crucial for evidence-based counseling while standardized protocols and guidelines are essential to ensure clinical value and respect of Ethical, Legal and Societal Issues.

12.
World J Clin Cases ; 12(22): 5168-5176, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39109004

RESUMO

BACKGROUND: The incidence of monodermal teratomas of the reproductive system is low, and most doctors lack adequate understanding, which can easily lead to missed diagnoses and/or misdiagnosis. Therefore, it is important to fully understand the clinical characteristics, diagnosis, differential diagnosis, and treatment of monodermal teratomas of the reproductive system. CASE SUMMARY: Case 1: A 14-year-old boy was admitted to the hospital with a right testicular mass for 1 wk and underwent surgical resection. He was finally diagnosed with right testicular monodermal teratoma with no special postoperative discomfort. Case 2: A 40-year-old woman was admitted to the hospital for uterine abnormalities indicated by ultrasound 20 d prior and underwent laparoscopic surgery. She was finally diagnosed with a left ovarian monodermal teratoma with a satisfactory postoperative quality of life. Case 3: A 49-year-old woman was admitted to the hospital with a pelvic mass that was discovered on B-ultrasound a week prior and underwent laparoscopic resection of the left adnexa. She was finally diagnosed with left ovarian monodermal teratoma, and her postoperative quality of life was satisfactory. CONCLUSION: Monodermal teratoma is a rare tumor whose clinical manifestations are primarily benign. Simple surgical resection of the tumor is effective.

13.
Sci Rep ; 14(1): 18153, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103404

RESUMO

Across the globe, many species of insects are facing population decline. This is largely driven by anthropogenic changes to the environment, including the widespread exposure of invertebrates to endocrine disrupting chemicals (EDCs), which impair fertility. To test whether generations of Drosophila melanogaster born from parents exposed to a common dietary EDC, equol, could recover reproductive function, we quantified the reproductive capacity of the two subsequent generations. Using a novel suite of flow cytometry assays to assess sperm functionality in real time, we find that sperm function is compromised across three generations, even after non-exposed in individuals contribute to the breeding population. Though the sex ratio alters in response to EDC exposure, favouring the survival of female offspring, most lineages with ancestral EDC exposure exhibit persistent subfertility in both the male and female. Male offspring with ancestral EDC exposure present with reduced fertility and dysfunctional spermatozoa, whereby spermatozoa are metabolically stressed, lack DNA integrity and present with permanent epigenetic alterations. Across generations, male and female offspring demonstrate distinct patterns of reproductive characteristics, depending upon the specific lineage of EDC exposure. Our results illustrate how dietary EDCs present in agricultural plants could promote transgenerational subfertility and contribute to declining insect populations.


Assuntos
Drosophila melanogaster , Disruptores Endócrinos , Fertilidade , Espermatozoides , Animais , Masculino , Disruptores Endócrinos/toxicidade , Feminino , Drosophila melanogaster/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Exposição Dietética/efeitos adversos , Infertilidade/induzido quimicamente , Reprodução/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Razão de Masculinidade
14.
Sci Rep ; 14(1): 18112, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103482

RESUMO

This study presents a computational investigation of a stochastic Zika virus along with optimal control model using the Legendre spectral collocation method (LSCM). By accumulation of stochasticity into the model through the proposed stochastic differential equations, we appropriating the random fluctuations essential in the progression and disease transmission. The stability, convergence and accuracy properties of the LSCM are conscientiously analyzed and also demonstrating its strength for solving the complex epidemiological models. Moreover, the study evaluates the various control strategies, such as treatment, prevention and treatment pesticide control, and identifies optimal combinations that the intervention costs and also minimize the proposed infection rates. The basic properties of the given model, such as the reproduction number, were determined with and without the presence of the control strategies. For R 0 < 0 , the model satisfies the disease-free equilibrium, in this case the disease die out after some time, while for R 0 > 1 , then endemic equilibrium is satisfied, in this case the disease spread in the population at higher scale. The fundamental findings acknowledge the significant impact of stochastic phonemes on the robustness and effectiveness of control strategies that accelerating the need for cost-effective and multi-faceted approaches. In last the results provide the valuable insights for public health department to enabling more impressive mitigation of Zika virus outbreaks and management in real-world scenarios.


Assuntos
Processos Estocásticos , Infecção por Zika virus , Zika virus , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/transmissão , Humanos , Zika virus/fisiologia , Simulação por Computador , Modelos Epidemiológicos
15.
Front Endocrinol (Lausanne) ; 15: 1361358, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104816

RESUMO

Objective: To investigate whether incising the septum facilitates reproductive outcomes for patients with a septate uterus compared to expectant management. Methods: Research was retrieved from three electronic databases: PubMed, Embase, and the Cochrane Library, with no time or language restrictions. Two authors independently selected the articles and extracted data regarding study characteristics, quality, and results. A random-effects model was employed, and summary risk ratios (RR) with 95% confidence intervals (CI) were calculated. Results: A total of 468 patients from two randomized controlled trials and one cohort study were included in the systematic review and meta-analysis. Pooled results showed that septum resection did not improve the live birth rate for patients with a septate uterus (RR = 0.84, 95% CI = 0.56 - 1.25, P = 0.39). Additionally, no significant differences were found between the septum resection and expectant management groups in terms of clinical pregnancy (RR = 1.08, 95% CI 0.81 - 1.44, P = 0.60), abortion (RR = 1.99, 95% CI 0.80 - 4.98, P = 0.14), and preterm delivery rates (RR = 0.99, 95% CI 0.42 - 2.31, P = 0.98). Conclusion: Our data provide clear evidence that septum resection does not improve the reproductive outcomes of patients with a septate uterus. These findings might be useful for revising current clinical guidelines.


Assuntos
Útero Septado , Feminino , Humanos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Útero Septado/cirurgia
16.
R Soc Open Sci ; 11(6): 231715, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39100187

RESUMO

Tuberculosis (TB) remains a significant global health concern, necessitating effective control strategies. This article presents a mathematical model to evaluate the comparative effectiveness of medical mask usage and case detection in TB control. The model is constructed as a system of ordinary differential equations and incorporates crucial aspects of TB dynamics, including slow-fast progression, medical mask use, case detection, treatment interventions and differentiation between symptomatic and asymptomatic cases. A key objective of TB control is to ensure that the reproduction number, R c , remains below unity to achieve TB elimination or persistence if R c exceeds 1. Our mathematical analysis reveals the presence of a transcritical bifurcation when the R c = 1 signifies a critical juncture in TB control strategies. These results confirm that the effectiveness of case detection in diminishing the endemic population of symptomatic individuals within a TB-endemic equilibrium depends on exceeding a critical threshold value. Furthermore, our model is calibrated using TB yearly case incidence data per 100 000 population from Indonesia, India, Lesotho and Angola. We employed the bootstrap resampling residual approach to assess the uncertainty inherent in our parameter estimates which provides a comprehensive distribution of the parameter values. Despite a declining trend in new incidence, these four countries exhibit a reproduction number greater than 1, indicating persistent TB cases in the presence of ongoing TB control programmes. We employ the partial rank correlation coefficient in conjunction with the Latin hypercube sampling method to conduct a global sensitivity analysis of the R c parameter for each fitted parameter in every country. We find that the medical mask use is more sensitive to reduce R c compared with the case detection implementation. To further gain insight into the necessary control strategy, we formulated an optimal control and studied the cost-effectiveness analysis of our model to investigate the impact of case detection and medical mask use as control measures in TB spread. Cost-effectiveness analysis demonstrates that combining these interventions emerges as the most cost-effective strategy for TB control. Our findings highlight the critical importance of medical masks and their efficacy coupled with case detection in shaping TB control dynamics, elucidating the primary parameter of concern for managing the control reproduction number. We envisage our findings to have implications and be vital for TB control if implemented by policymakers and healthcare practitioners involved in TB control efforts.

17.
Conserv Physiol ; 12(1): coae048, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39100510

RESUMO

Hormone monitoring of at-risk species can be valuable for evaluation of individual physiological status. Traditional non-invasive endocrine monitoring from urine and faeces typically captures only a short window in time, poorly reflecting long-term hormone fluctuations. We examined toenail trimmings collected from African (Loxodonta africana) and Asian (Elephas maximus) elephants during routine foot care, to determine if long-term hormone patterns are preserved in these slow-growing keratinized tissues. We first measured the growth rate of elephant toenails biweekly for one year, to establish the temporal delay between deposition of hormones into nail tissue (at the proximal nail bed) and collection of toenail trimmings months later (at the distal tip of the nail). In African elephants, toenails grew ~0.18 ± 0.015 mm/day (mean ± SEM) and in Asian elephants, toenails grew ~0.24 ± 0.034 mm/day. This slow growth rate, combined with the large toenail size of elephants, may mean that toenails could contain a 'hormone timeline' of over a year between the nail bed and nail tip. Progesterone, testosterone and cortisol were readily detectable using commercial enzyme immunoassays, and all assays passed validations, indicating that these hormones can be accurately quantified in elephant toenail extract. In most cases, variations in hormone concentrations reflected expected physiological patterns for adult females and males (e.g. ovarian cycling and musth) and matched individual health records from participating zoos. Progesterone patterns aligned with our calculations of temporal delay, aligning with female ovarian cycling from over six months prior. Unexpectedly, male testosterone patterns aligned with current musth status at the time of sample collection (i.e. rather than prior musth status). Though this sample type will require further study, these results indicate that preserved hormone patterns in elephant toenails could give conservationists a new tool to aid management of elephant populations.

18.
Lab Anim ; : 236772241244834, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39102523

RESUMO

Ad libitum feeding of laboratory zebrafish has potential benefits for colony management, but would require a new type of diet, such as a gel that remains in the tank. We hypothesized that adult zebrafish fed a gel diet would have similar body size and reproductive success compared with those fed a standard micro-pellet diet. The gel diet's impact on water quality was determined to be safe for zebrafish prior to starting a 12-week feeding study. Two hundred adult AB zebrafish of mixed sex were randomly assigned to be fed exclusively either gel or micro-pellet diet. Fish body length and mass were measured every two weeks, and fish were bred within each feed group to assess fecundity. Zebrafish consumed less gel diet than expected. Body length, mass, and breeding success were lower in the gel diet fish than in the micro-pellet diet fish. Low consumption of the gel diet and/or nutritional differences between the two diets may have contributed to reduced growth and fecundity. Though the gel diet could reduce time personnel spend feeding and be safer for fish in static tanks, the tested formulation was not a satisfactory alternative to the control micro-pellet diet in a research zebrafish colony.

20.
Res Vet Sci ; 177: 105368, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39098094

RESUMO

To boost the immune function around parturition, recombinant bovine granulocyte colony-stimulating factor (rbG-CSF) has been used to increase the number of neutrophils. Therefore, the aim of this study was to quantify the effect of rbG-CSF administration on the incidence of postpartum pathologies, reproductive performance, and milk production during the first three months of lactation. A total of 199 Holstein cows from one herd were included and were randomly allocated into two groups: Control (n = 103) and rbG-CSF (n = 96). Cows in the rbG-CSF group received 2 doses of a rbG-CSF injectable formulation, one 7 days before the expected date of calving and the other within 24 h after calving. For 6 weeks following calving, animals were examined weekly to assess the presence of postpartum pathologies. Milk production, protein and fat content, and somatic cell count were determined monthly by the regional dairy herd improvement association. Data about the reproductive performance were collected from on-farm software. To analyse the effect of treatment on the incidence of postpartum pathologies, Pearson's χ2 test and multivariable logistic regressions were performed. The effect on reproductive performance was analysed using Cox proportional hazard regression analysis for days open, binary logistic regression for first service conception rate and Oneway ANOVA test for the number of artificial inseminations. The effects of treatment on milk yield and milk composition were checked using GLM repeated measures analysis. No statistically significant differences were observed between treatment groups for any of the parameters evaluated. Only parity had a significant effect on days open and milk production (p < 0.05). In conclusion, in the present study no evidence was found that rbG-CSF could have an effect on the reproductive and productive parameters evaluated.

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