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1.
Animals (Basel) ; 14(2)2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38275785

RESUMO

Piglet mortality during lactation is a significant concern in swine production, influenced by complex interactions involving sow, piglet, environmental, and management factors. While crushing by the sow may be the ultimate cause of piglet mortality, there are many factors influencing the outcome, including parity, thermal stress, and animal housing systems. New farrowing systems are continuously being developed; however, it is difficult for producers to make decisions without any scientific basis. This study aimed to assess the impact of different farrowing pen layouts on piglet performance, considering parity and season. A total of 546 sows and 9123 piglets were monitored across 36 lactation cycles. Sows were randomly assigned to three farrowing pen layouts (standard, diagonal, and offset) in three rooms (20 sows by room). All farrowing pens had the same space allocations (2.7 m by 1.8 m and 2.1 m by 0.6 m for the sow area). The three types of farrowing pens were blocked by position within the room. Piglet performance traits (percent of stillborns, percent of mortality, percent of overlays, and average daily weight gain: ADG) and sows traits (health and parity) were monitored following US Meat Animal Research Center (USMARC) procedures. Results indicated that treatment, parity, and season influenced some piglet performance traits. The offset farrowing pen had a lower percent of stillborns compared to the standard. No significant differences were observed between the diagonal crate and the other treatments. When evaluating high mortality sow (>two piglets), the offset and standard treatments had a lower percent of overlays. Piglets from first-parity sows had lower ADG than those from higher-parity sows. A higher percent of overlays were observed in Autumn and Summer compared to Spring and Winter, and Summer had lower average daily weight gain than other seasons. The results suggest that modifying the layout (offset), with sows placed further away from the heating source, can reduce the percent of overlays in sows with high mortality (>2 piglets). In addition, the influence of season on the piglet production traits demonstrated the importance of proper management of the environment, even in systems with a certain level of climatic control.

2.
J Neuroendocrinol ; 36(1): e13357, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056947

RESUMO

This study furthers the investigation of how pituitary adenylate cyclase activating polypeptide (PACAP) and the PAC1 receptor (PAC1R) regulate the homeostatic energy balance circuitry. We hypothesized that apoptotic ablation of PACAP neurones in the hypothalamic ventromedial nucleus (VMN) would affect both energy intake and energy expenditure. We also hypothesized that selective PAC1R knockdown would impair the PACAP-induced excitation in anorexigenic proopiomelanocortin (POMC) neurones and inhibition of orexigenic neuropeptide Y (NPY)/agouti-related peptide (AgRP) neurones in the hypothalamic arcuate nucleus (ARC). The results show CASPASE-3-induced ablation of VMN PACAP neurones leads to increased energy intake and meal frequency as well as decreased energy expenditure in lean animals. The effects were more robust in obese males, whereas we saw the opposite effects in obese females. We then utilized visualized whole-cell patch clamp recordings in hypothalamic slices. PAC1R knockdown in POMC neurones diminishes the PACAP-induced depolarization, increase in firing, decreases in energy intake and meal size, as well as increases in CO2 production and O2 consumption. Similarly, the lack of expression of the PAC1R in NPY/AgRP neurones greatly attenuates the PACAP-induced hyperpolarization, suppression of firing, decreases in energy intake and meal frequency, as well as increases in energy expenditure. The PACAP response in NPY/AgRP neurones switched from predominantly inhibitory to excitatory in fasted animals. Finally, the anorexigenic effect of PACAP was potentiated when oestradiol was injected into the ARC in ovariectomized females. This study demonstrates the critical role of anorexigenic VMN PACAP neurones and the PAC1R in exciting POMC and inhibiting NPY/AgRP neurons to control homeostatic feeding.


Assuntos
Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Pró-Opiomelanocortina , Animais , Masculino , Feminino , Pró-Opiomelanocortina/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Neuropeptídeo Y/metabolismo , Proteína Relacionada com Agouti/metabolismo , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Núcleo Hipotalâmico Ventromedial/metabolismo , Núcleo Arqueado do Hipotálamo/metabolismo , Dieta , Neurônios/metabolismo , Obesidade/metabolismo
3.
J Therm Biol ; 115: 103609, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37433235

RESUMO

Recent studies have investigated the use of infrared thermography (IRT) to monitor body surface temperature and correlate it with factors related to animal welfare and performance. In this context, this work proposes a new method for extracting characteristics for the temperature matrix obtained using IRT data from regions of the body surface of cows which, if associated with environmental variables through a machine learning algorithm it generates computational classifiers for heat stress condition. IRT data were collected from different parts of the body of 18 lactating cows housed in a free-stall, monitored for 40 non-consecutive days, three times a day (5:00 a.m., 1:00 p.m., and 7:00 p.m.), during summer and winter, along with physiological data (rectal temperature and respiratory rate) and meteorological data for each time. The IRT data is used to create a descriptor vector based on frequency, accounting for temperatures for a pre-defined range, referred to in the study as 'Thermal Signature' (TS). The generated database was used for training and assessing computational models based on Artificial Neural Network (ANN) to classify heat stress conditions. The models were built using the following predictive attributes for each instance: TS, air temperature, black globe temperature and wet bulb temperature. The goal attribute used for supervised training was the heat stress level classification generated from the rectal temperature and respiratory rate values measured. The models based on different ANN architectures were compared through metrics of the confusion matrix between predicted and measured data, obtaining better results with 8 TS ranges. The best accuracy for classification into four heat stress levels (Comfort, Alert, Danger, and Emergency) was 83.29% using the TS of the ocular region. The classifier for two heat levels of stress (Comfort and Danger) obtained accuracy of 90.10% also using the 8 TS bands of the ocular region.


Assuntos
Transtornos de Estresse por Calor , Termografia , Feminino , Bovinos , Animais , Termografia/métodos , Lactação , Temperatura Corporal/fisiologia , Resposta ao Choque Térmico , Modelos Animais , Transtornos de Estresse por Calor/veterinária
4.
J Emerg Manag ; 21(2): 155-163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37270414

RESUMO

Hurricane Maria was a disastrous weather event that devastated Puerto Rico (PR) in September 2017. Yet, little is known about people's perceptions of this event. In this investigation, we offer insight about Hurricane Maria's impact on PR's inhabitants. More specifically, we study a sample (n = 542 responses) of individuals' worry levels through four time points during the aftermath of Hurricane Maria: their variation through time, their relationship to decision making, and if and how certain demographic variables may influence them. For these purposes, we designed and implemented the Individual Emergency Response and Recovery Questionnaire, a web-based survey that measured several aspects of the objective and subjective experiences of individuals who underwent Hurricane Maria in PR. Results of a statistical analysis using nonparametric tests show that some of the demographic variables selected as factors of interest influence the worry levels reported by respondents. Most significant results coincide with conclusions drawn by literature: that time, age group, and the level of information influence worry levels. Another key finding is that the worry level may influence individual decision-making frequency. Understanding principal factors in people's behavior and perceptions during hurricanes is crucial to help us learn how to better prepare for and respond to natural disasters in the future.


Assuntos
Tempestades Ciclônicas , Desastres , Desastres Naturais , Humanos , Porto Rico , Inquéritos e Questionários
5.
J Emerg Manag ; 19(8): 157-165, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36239505

RESUMO

Situations faced in the advent of powerful hurricanes can be stressful for individuals due to the uncertainty they bring along. The consequences of these phenomena can leave individuals' recovery in their own hands until order is re-established, and support can reach out to them. This work aims to develop a tool to guide individuals through their decision-making during a hurricane disaster and recovery, using the experience of Hurricane María. The tool is a classic inventory model adapted to monitor individual's wellness through 48 hours after a hurricane arrival. This article presents the three stages followed in the development in this work: the assessment of individuals' sentiments toward Hurricane María via an online questionnaire, the development of the mathematical model, and the creation of a prototype in the form of a mobile application. Each phase presents an important contribution: a summary of first-hand knowledge obtained from the reactions of individuals who survived Hurricane María, a novel modeling approach to the problem, and a convenient framework that synthesizes both previous components.


Assuntos
Tempestades Ciclônicas , Desastres , Humanos , Inquéritos e Questionários
6.
Int J Biometeorol ; 66(12): 2477-2488, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36201039

RESUMO

This study aimed to evaluate the change in the air temperature and the impacts of heat waves using Climate Change Indexes on the physiological and productive responses of lactating Holstein cows. Daily data of maximum and minimum air temperature for 1981-2021 were used. Heat waves were determined using six Climate Change Indexes. Individual data on respiratory rate, rectal temperature, and milk yield were collected in the summers of 2018, 2019, and 2021. The temperature trend analysis showed a significant (p < 0.0001) increase in maximum temperature, minimum temperature, and days in a heat wave. All six indexes increased significantly (p > 0.01). The increase in warm nights (> 20 °C) and the hottest days (> 35 °C) was the highest since 2010. Heat waves were classified into short (< 5 days) and long (> 5 days) of greater (> 36 °C) or lesser (< 36 °C) intensity. During the long and short heat waves of greater intensity, the respiratory rate increased (p < 0.05) until the fourth day. On the other hand, rectal temperature was higher (p < 0.05) from the fourth day until the end of the long heat waves. Therefore, the decrease in milk yield was significantly greater from the fourth or fifth day onwards. Finally, the evaluation method based on indexes was efficient to demonstrate the negative effects on physiological parameters and milk yield and can be indicated to evaluate heat stress in lactating cows.


Assuntos
Transtornos de Estresse por Calor , Lactação , Feminino , Bovinos , Animais , Lactação/fisiologia , Temperatura Corporal , Leite , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico/fisiologia , Temperatura Alta
7.
J Physiol ; 600(22): 4939-4961, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36217719

RESUMO

We tested the hypothesis that N/OFQ neurones in the arcuate nucleus (N/OFQARC ) inhibit proopiomelanocortin (POMCARC ) neurones in a diet- and hormone-dependent manner to promote a more extensive rebound hyperphagia upon re-feeding following an 18 h fast. We utilized intact male or ovariectomized (OVX) female mice subjected to ad libitum-feeding or fasting conditions. N/OFQARC neurones under negative energy balance conditions displayed heightened sensitivity as evidenced by a decreased rheobase threshold, increased firing frequency, and increased burst duration and frequency compared to ad libitum-feeding conditions. Stimulation of N/OFQARC neurones more robustly inhibited POMCARC neurones under fasting conditions compared to ad libitum-feeding conditions. N/OFQARC inhibition of POMCARC neurones is hormone dependent as chemostimulation of N/OFQARC neurones from fasted males and OVX females produced a sizable outward current in POMCARC neurones. Oestradiol (E2 ) markedly attenuated the N/OFQ-induced POMCARC outward current. Additionally, N/OFQ tonically inhibits POMCARC neurones to a greater degree under fasting conditions than in ad libitum-feeding conditions as evidenced by the abrogation of N/OFQ-nociceptin opioid peptide (NOP) receptor signalling and inhibition of N/OFQ release via chemoinhibition of N/OFQARC neurones. Intra-arcuate nucleus application of N/OFQ further elevated the hyperphagic response and increased meal size during the 6 h re-feed period, and these effects were mimicked by chemostimulation of N/OFQARC neurones in vivo. E2 attenuated the robust N/OFQ-induced rebound hyperphagia seen in vehicle-treated OVX females. These data demonstrate that N/OFQARC neurones play a vital role in mitigating the impact of negative energy balance by inhibiting the excitability of anorexigenic neural substrates, an effect that is diminished by E2 in females. KEY POINTS: Nociceptin/orphanin FQ (N/OFQ) promotes increased energy intake and decreased energy expenditure under conditions of positive energy balance in a sex- and hormone-dependent manner. Here it is shown that under conditions of negative energy balance, i.e. fasting, N/OFQ inhibits anorexigenic proopiomelanocortin (POMC) neurones to a greater degree compared to homeostatic conditions due to fasting-induced hyperexcitability of N/OFQ neurones. Additionally, N/OFQ promotes a sustained increase in rebound hyperphagia and increase in meal size during the re-feed period following a fast. These results promote greater understanding of how energy balance influences the anorexigenic circuitry of the hypothalamus, and aid in understanding the neurophysiological pathways implicated in eating disorders promoting cachexia.


Assuntos
Estradiol , Pró-Opiomelanocortina , Masculino , Feminino , Camundongos , Animais , Pró-Opiomelanocortina/metabolismo , Estradiol/farmacologia , Peptídeos Opioides/farmacologia , Peptídeos Opioides/metabolismo , Metabolismo Energético , Hiperfagia , Nociceptina
8.
Front Endocrinol (Lausanne) ; 13: 877647, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35721722

RESUMO

Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP), a pleiotropic neuropeptide, is widely distributed throughout the body. The abundance of PACAP expression in the central and peripheral nervous systems, and years of accompanying experimental evidence, indicates that PACAP plays crucial roles in diverse biological processes ranging from autonomic regulation to neuroprotection. In addition, PACAP is also abundantly expressed in the hypothalamic areas like the ventromedial and arcuate nuclei (VMN and ARC, respectively), as well as other brain regions such as the nucleus accumbens (NAc), bed nucleus of stria terminalis (BNST), and ventral tegmental area (VTA) - suggesting that PACAP is capable of regulating energy homeostasis via both the homeostatic and hedonic energy balance circuitries. The evidence gathered over the years has increased our appreciation for its function in controlling energy balance. Therefore, this review aims to further probe how the pleiotropic actions of PACAP in regulating energy homeostasis is influenced by sex and dynamic changes in energy status. We start with a general overview of energy homeostasis, and then introduce the integral components of the homeostatic and hedonic energy balance circuitries. Next, we discuss sex differences inherent to the regulation of energy homeostasis via these two circuitries, as well as the activational effects of sex steroid hormones that bring about these intrinsic disparities between males and females. Finally, we explore the multifaceted role of PACAP in regulating homeostatic and hedonic feeding through its actions in regions like the NAc, BNST, and in particular the ARC, VMN and VTA that occur in sex- and energy status-dependent ways.


Assuntos
Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Núcleos Septais , Metabolismo Energético/fisiologia , Feminino , Homeostase , Humanos , Hipotálamo/metabolismo , Masculino , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Núcleos Septais/metabolismo
9.
Transfus Med ; 32(2): 153-161, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35001439

RESUMO

INTRODUCTION: South America is one of the regions most affected by the COVID-19 pandemic. Specific and affordable treatments are needed to treat SARS-CoV-2 infection. Evidence regarding the use of convalescent plasma in COVID-19 patients is still limited. We compared the safety and efficacy of COVID-19-convalescent plasma administration as a complement to standard treatment in the early management of patients with moderate SARS-CoV-2 infection. METHODS: We carried out a random double blinded, placebo-controlled trial that compared standard treatment plus convalescent plasma (CP) or plus non-convalescent plasma in the management of COVID-19 patients. The main outcome was survival and secondary endpoints included: length of hospitalisation (LOH), days from treatment to discharge, time to clinical improvement or death within a 28-day period, and adverse reactions to treatment. RESULTS: Administration of CP with antibodies against SARS-CoV-2 did not affect patient survival, RR = 1.003, 95% CI (0.3938, 2.555). These results led to terminate the RCT prematurely. However, early treatment of COVID-19 patients with CP tended to decrease the LOH while the delay in CP treatment was associated with longer hospitalisation. In addition, delay in CP treatment negatively affected the recovery of the respiratory rate. CONCLUSION: Use of CP for the treatment of COVID-19 patients is safe and its early use can decrease the LOH and improve respiratory function. Early administration of antibody-rich CP could contribute to decrease the negative impact of COVID-19 pandemic in patients with impaired immune response.


Assuntos
COVID-19 , Imunização Passiva , COVID-19/terapia , Humanos , Imunização Passiva/métodos , Pandemias , SARS-CoV-2 , Soroterapia para COVID-19
10.
Anim Biosci ; 34(9): 1552-1558, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32299174

RESUMO

OBJECTIVE: This work was carried out to evaluate the effects of zilpaterol hydrochloride (ZH) and ractopamine hydrochloride (RH) combined with immunocastration on the welfare traits of feedlot Nellore cattle. METHODS: Ninety-six Nellore males (average body weight [BW] = 409±50 kg; average 20 mo of age) were divided into two groups according to BW; half of the animals in each group received two doses of an immunocastration (ImC) vaccine in a 30 day interval, and the other half did not receive the vaccine (NoC). Afterward, the animals were housed and fed a common diet for 70 days. Then, they were split into three groups and fed one of the following diets for 30 additional days: control (CO) diet, with no ß-AA; ZH diet, containing 80 mg/d ZH; and RH diet, containing 300 mg/d RH. Welfare traits were assessed by monitoring body surface temperature using infrared thermography (IRT) and plasma cortisol and temperament measurements. RESULTS: There was no interaction between sexual condition and diet for any trait. The ImC and NoC groups did not differ in rectal and ocular temperatures. The ImC animals had higher flight speeds (p = 0.022) and tended to have higher cortisol levels (p = 0.059) than the NoC animals. Animals fed ZH and RH did not differ in cortisol levels, respiratory rate, rectal temperature, temperature measured by IRT, or temperament behaviour. CONCLUSION: The ImC animals showed a less stable temperament during handling practices than NoC, whereas ZH and RH supplementation had no adverse effects on animal welfare.

11.
J Exp Biol ; 221(Pt 18)2018 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-30104303

RESUMO

Temperature-correlated shifts in reproductive timing are now well documented in numerous bird species. However, whether temperature directly influences reproductive timing or whether its effects are mediated by an intermediate environmental cue, such as plant phenology, remains poorly understood. In this study, we investigated the direct effects of temperature on reproductive timing in house finches (Haemorhous mexicanus), which have a range and breeding diet not well represented in previous studies of temperature and reproductive timing. We conducted experiments with captive male house finches in which temperature was elevated within realistic ranges and the effects on the timing of preparations for reproduction, as well as on the termination of reproduction and the onset of prebasic feather molt, were examined. We found no adjustments in the timing of reproductive preparations of males in direct response to temperature. However, elevated temperature did advance the breeding-molt transition. Our results suggest that elevated temperatures in the range tested here do not directly impact physiological preparations for reproduction in male house finches, but may constrain the timing of the breeding-molt transition in this species.


Assuntos
Dieta/veterinária , Tentilhões/fisiologia , Muda , Comportamento de Nidação , Reprodução/fisiologia , Temperatura , Animais , Masculino , Fatores de Tempo
12.
Pathog Dis ; 70(2): 167-75, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24339197

RESUMO

Atypical enteropathogenic Escherichia coli (aEPEC) strains produce attaching-effacing (AE) lesions on enterocytes due to the interaction of the adhesin intimin with its translocated receptor. aEPEC strain 1551-2 was previously shown to invade HeLa and T84 cells by means of the uncommon intimin subtype omicron. Other aEPEC strains carrying uncommon intimin subtypes have also been shown to invade differentiated T84 intestinal cells. In this study, seven aEPEC strains carrying the most common EPEC intimin subtypes (alpha, beta, and gamma) were evaluated regarding the ability to invade differentiated intestinal Caco-2 cells. Although all strains adhered to and promoted AE lesions, the numbers of cell-associated bacteria varied significantly between the different strains regardless of the intimin subtype (P < 0.05). Gentamicin protection assay and transmission electron microscopy analyses showed that in comparison with the invasive strain 1551-2, only one strain (aEPEC EC423/03, intimin beta) was invasive (P = 0.05). Although both strains persisted intracellularly until 48 h, the number of viable bacteria of EC423/03 decreased, whereas that of 1551-2 increased significantly up to 24 h and then decreased. In conclusion, invasiveness is a sporadic property among aEPEC strains carrying some common intimin subtypes.


Assuntos
Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Endocitose , Enterócitos/microbiologia , Escherichia coli Enteropatogênica/fisiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Animais , Antibacterianos/farmacologia , Células CACO-2 , Bovinos , Criança , Pré-Escolar , Escherichia coli Enteropatogênica/classificação , Escherichia coli Enteropatogênica/genética , Escherichia coli Enteropatogênica/isolamento & purificação , Gentamicinas/farmacologia , Humanos , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Transmissão
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