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In 2021 BL Lacertae underwent an extraordinary activity phase, which was intensively followed by the Whole Earth Blazar Telescope (WEBT) Collaboration. We present the WEBT optical data in the BVRI bands acquired at 36 observatories around the world. In mid-2021 the source showed its historical maximum, with R  = 11.14. The light curves display many episodes of intraday variability, whose amplitude increases with source brightness, in agreement with a geometrical interpretation of the long-term flux behaviour. This is also supported by the long-term spectral variability, with an almost achromatic trend with brightness. In contrast, short-term variations are found to be strongly chromatic and are ascribed to energetic processes in the jet. We also analyse the optical polarimetric behaviour, finding evidence of a strong correlation between the intrinsic fast variations in flux density and those in polarization degree, with a time delay of about 13 h. This suggests a common physical origin. The overall behaviour of the source can be interpreted as the result of two mechanisms: variability on time-scales greater than several days is likely produced by orientation effects, while either shock waves propagating in the jet, or magnetic reconnection, possibly induced by kink instabilities in the jet, can explain variability on shorter time-scales. The latter scenario could also account for the appearance of quasi-periodic oscillations, with periods from a few days to a few hours, during outbursts, when the jet is more closely aligned with our line of sight and the time-scales are shortened by relativistic effects. [ABSTRACT FROM AUTHOR]

In tropical and subtropical climate regions, heat stress is one of the main causes of production losses in laying quails, aggravated by the antinutritional effects of the phytate in diet ingredients, which negatively affect the bioavailability of minerals, especially calcium and phosphorus. This situation results in a reduction in production and the quality of eggs from commercial laying quails. Several nutritional strategies are utilized to reduce the adverse effects of high temperatures and antinutritional factors such as phytate. Among these strategies, the use of exogenous enzymes, such as phytase, stands out as a viable alternative. Phytase breaks down phytate molecules, optimizing the absorption of essential minerals and improving productive performance and egg quality under unfavorable conditions. Specifically, it is recommended to use 1500 FTU of phytase, as it not only reduces the effects of thermal stress but also enhances eggshell thickness and calcium absorption. In this context, this bibliographic review sought to produce a document demonstrating the beneficial effects of the phytase enzyme on the hydrolysis of the phytate molecule, the availability of calcium for Japanese quails (Coturnix japonica), and its implications in thermal stress due to heat.

Abstract This study evaluated the effects of broiler age (A) and levels of replacement (L) of control diet (CD) on the utilization of energy and nutrients of whole corn germ. 720 one-day-old broilers (b) were allocated at completely randomized design to six treatments and six replicates, in three assays: pre-starter (1-8 days, 10 b/cage), starter (15-22 days, 6 b/cage), and grower (28-35 days, 4 b/cage) phases. The treatments were: CD and four test diets (L): 100, 150, 200, 250, or 300 g kg-1 of the CD replaced by WCG levels. The data were adjusted to the response surface model. The stationary points for apparent energy metabolizable (AME) and AME corrected for nitrogen balance (AMEn) were: 4173 and 3591 kcal kg-1, respectively, and coefficients of gross energy (AMCGE), crude protein (AMCCP), dry matter (AMCDM), and ether extract (AMCEE) were: 49.3, 40.4, 72.6, and 61.3%, respectively; and Ileal digestibility coefficient of crude protein (IDCCP), dry matter (IDCDM), digestibility crude protein values (DCP), and digestibility dry matter value (DDM) were: 78.0, 57.96, 8.50, and 56.17%, respectively. The EP for AMEn was at 18 days of age, 28 g kg-1 WCG. There was a correlation between A and L on digestibility and metabolisability of nutrient’s WCG.

This study aimed to evaluate the nutritive value of three feeds (Cecropia sp., Pterodon sp., and Inga sp.) for sloths (Bradypus variegatus), based on nutritional composition and in vitro gas production. After a 14-day adaptation period to these feeds, approximately 500 g of gastric contents were collected from three female sloths, processed, and incubated with the food samples to evaluate digestibility and in vitro degradation kinetics. Regarding the nutritional composition, the neutral detergent fiber (NDFcp) content was higher with 404 g kg−1 DM (p = 0.001) in the leaves of Cecropia sp. The non-fibrous carbohydrate contents were greater with 499 g kg−1 DM in Pterodon sp. (p = 0.002). The greatest cellulose content (211 g kg−1 DM) was found in the leaves of C. pachystachya, as well as the lowest value of 143 g kg−1 DM for hemicellulose. Significant differences in the in vitro digestibility of crude protein (p = 0.041) were observed, with Inga sp. showing the highest value at 547 g kg−1 DM. In terms of kinetic parameters, Pterodon sp. exhibited higher total gas production (Vt) at 99 mL (p = 0.023) and digestion rates of fibrous carbohydrates (kdFC) at 0.0223%/h (p = 0.020) (p < 0.05). The leaves of Pterodon sp. and Inga sp. showed potential as suitable feeds for B. variegatus, while Cecropia sp. may have negative effects on dry matter intake due to its high NDF content, because of possible repletion effects on the stomach.

The objective of this study was to evaluate the performance of commercial laying hens fed with different levels of Moringa oleifera leaf meal in their diet. For this purpose, 150 laying hens of the Dekalb White lineage, at 62 weeks of age, and with an initial average weight of 1.458 kg ± 8.70g, were used. They were housed in cages measuring 1.00 X 0.40 X 0.45m, equipped with chute-type feeders, automatic cup-type drinkers and chute for collecting eggs. They were distributed in a completely randomized design, consisting of five treatments with five replications of six birds. The treatments consisted of a reference diet, without moringa inclusion, and four test diets with levels of 1.5%, 3.0%, 4.5% and 6% inclusion of moringa leaf meal. Water was provided ad libitum, and 120 g of feed per bird per day. The total experimental period lasted 122 days. The data obtained were subjected to analysis of variance and Dunnett's test at 5% significance and, when significant, subjected to regression analysis. Analysis of the leaf flour revealed the presence of antinutritional factors in small concentrations. It was observed that the addition of moringa to the birds' diet did not influence performance parameters and provided significant increases in the average egg weight according to moringa inclusion levels of 1.5%, 4.5% and 6% when compared to the control diet, as well as a significant increase in the color of the egg yolks for all levels tested (1.5 to 6%). A reduction in Haugh unit values was observed when inclusion levels of moringa were 4.5% and 6%. Despite a reduction in Haugh unit values, they are still within the classification standards. Analysis of the biochemical parameters of the birds' blood serum did not show significant influences according to the levels of moringa inclusion in the diet, although a numerical reduction was observed in the cholesterol levels of birds fed with an inclusion of 6% of leaf flour in the diet, which could possibly be related to the presence of phytochemical compounds, more precisely β-sitosterol. Moringa oleifera leaf meal can be used to feed laying birds without causing harm to the birds' performance, in addition to intensifying the color of the yolks.

A preguiça-comum (Bradypus variegatus) tem sido vítima das investidas antrópicas desordenadas, o que tem elevado o número de acidentes e doenças para a espécie. Propôs-se com esse estudo, realizar uma descrição das artérias coronárias, assim como apontar os achados histopatológicos do coração do bicho-preguiça, a fim de favorecer o diagnóstico por imagem, semiologia e clínica médica das espécies. Foram dissecados 18 exemplares de B. variegatus obtidos após morte natural. Quinze deles, sendo 5 machos e 9 fêmeas adultas e 1 jovem, foram fixados com formaldeído e conservados em solução salina. Em 2 machos e 1 fêmea, foi injetado, a partir da artéria carótida comum esquerda, látex corado em vermelho, para tornar as coronárias mais evidentes. Na fêmea também foi injetado através da veia jugular externa direita, látex corado em azul, para evitar equívoco na identificação arterial. Os animais tiveram o tórax aberto a fim de avaliar e retirar o coração para descrição detalhada das artérias coronárias. Para análise histopatológica, foram confeccionadas lâminas histológicas oriundas de corações coletados de 4 animais (3 adultos e 1 jovem). Com base nas análises arteriais, as preguiças possuem duas coronárias: uma a direita e uma a esquerda, que irrigam suas respectivas faces. O coração é composto por endocárdio, miocárdio e epicárdio, semelhante aos mamíferos em geral. Todavia, observou-se necroses endocárdicas, de fibras musculares cardíacas, além de degenerações mixomatosas de válvulas e trombos no lúmen vascular. Esses eventos necróticos, mais extensos, estão relacionados a infartos, enquanto os mais discretos podem ser associados a situações de estresse vivenciadas pelos espécimes.

Sloths are wild animals with arboreal habits, with slow metabolism, found in tropical forests from South America to Central America. However, the lack of knowledge of their anatomy does not favor the conservation of the species in veterinary care centers, due to its peculiar anatomy. Therefore, the objective of this study was to describe the topography and morphology of the spleen of the species Bradypusvariegatus, in order to collect more information to support and assist in the clinical-surgical processes of the species. Eight corpses of B. variegatus, previously fixed with 20% formaldehyde and preserved in 30% saline solution, were dissected for the macroscopic study of the spleen. A healthy animal, living in semi-captivity, was assigned to perform a tomography of the abdominal region, for observation of the spleen, while two specimens were destined for the microscopic study of the organ immediately after death. Based on the data obtained, the spleen presented a topography and tissue composition similar to other mammals, but its morphology, absence of visceral lienal hilum and anatomical arrangement in the abdominal cavity differed from most domestic and wild animals.