Anatomical and histological traits of Brycon amazonicus liver cultivated in a semi-intensive system

The work aimed to evaluate the weight-length relationship and the condition factor, characterizing the biometry, anatomy, histology and volumetric density of the liver of Brycon amazonicus, in different stages of body growth. The experiment used twenty specimens in four stages of body growth (PI, PII, PIII and PIV) harvested every 90 days, containing five specimens, each group. The livers were dissected, weighed (g) and processed routinely using the hematoxylin and eosin technique. The data were submitted to analysis of variance, Pearson’s correlation test and linear regression. The equation that represented the weight-length relation was W = 0.05902 x L2.63, with negative allometric growth, but with a relative condition factor equal to 1.0. The liver was divided into three lobes with the gallbladder close to the right lobe and its color varied from light red to dark red, not varying in relation to other fish species. The hepatosomatic relationship followed body growth until the PII group stage and then declined, demonstrating the behavior of its development in Brycon amazonicus. The organ consists predominantly of hepatocytes, followed by sinusoidal vessels and capillaries, with histological morphology similar to that of many species of fish. Melanomacrophage centers were found only in the most developed animals, but in small quantities, prompting the development of new research on this cell, in this species. In this way, research of this nature allows the characterization of fish species, helping to improve breeding methods, understanding pathological processes caused by diseases, and obtaining better productive capacity, serving an increasingly demanding and prosperous market.

Antenatal Antibiotic Exposure Affects Enteral Feeding, Body Growth, and Neonatal Infection in Preterm Infants: A Retrospective Study

Background: Antibiotics are widely prescribed by obstetricians, which exposes a large number of infants to antenatal antibiotics (AAB). The effect of AAB on various aspects of neonatal development of preterm infants remains unclear.Methods: In this retrospective study, infants born with gestational age (GA) between 22 +0 and 36 +6 weeks at our unit from 2017 to 2019 were included. Multivariable analysis was adopted to examine the associations between AAB exposure and various outcomes related to enteral feeding process, body growth, and neonatal infection after adjusting for potential confounders. Further subanalysis on the exposure level of AAB and stratified analysis by GA (<34 vs. ≥34 weeks) were also conducted.Results: In this cohort comprising 2,543 preterm infants, AAB was associated with decreased risks of feeding intolerance (odds ratio [OR]: 0.63, 95% confidence interval [CI]: 0.48–0.82) and neonatal infection (OR: 0.63, 95% CI: 0.41–0.94). Higher AAB exposure level was associated with higher Z scores of birth weight (β = 0.37, 95% CI: 0.27–0.47), but lower Δbodyweight Z-scores (β = −0.20, 95% CI: −0.27 to −0.13). AAB was positively associated with the parameters related to body growth in infants with GA <34 weeks but negatively associated in those with GA ≥34 weeks.Conclusions: AAB exposure affects the enteral feeding process and neonatal infection. The effects on body growth vary by the exposure level of AAB and GA of infants. A well-designed prospective and preferably multi-centre study with predefined parameters is required to confirm our findings.

Allocation costs of regeneration: tail regeneration constrains body growth under low food availability in juvenile lizards

The balance of energy allocated to development and growth of different body compartments may incur allocation conflicts and can thereby entail physiological and evolutionary consequences. Regeneration after autotomy restores the functionality lost after shedding a body part but requires a strong energy investment that may trade-off with other processes, like reproduction or growth. Caudal autotomy is a widespread antipredator strategy in lizards, but regeneration may provoke decreased growth rates in juveniles that could have subsequent consequences. Here, we assessed the growth of intact and regenerating hatchling wall lizards (Podarcis muralis) exposed to different food regimens. Regenerating juveniles presented slightly but significantly lower body growth rates than individuals with intact tails when facing low food availability, but there were no differences when food was supplied ad libitum. Regenerating individuals fed ad libitum increased their ingestion rates compared to intact ones during the period of greatest tail growth, which also reveals a cost of tail regeneration. When resources were scarce, hatchlings invested more in tail regeneration in relation to body growth, rather than delay regeneration to give priority to body growth. We propose that, in juvenile lizards, regeneration could be prioritized even at the expense of body growth to restore the functionality of the lost tail, likely increasing survivorship and the probability to reach reproductive maturity. Our study indicates that food availability is a key factor for the occurrence of trade-offs between regeneration and other growth processes, so that environmental conditions would be determinant for the severity of the costs of regeneration.

Incubation temperature and physiological aging in the zebra finch

In birds, incubation temperature has received increased attention as an important source of phenotypic variability in offspring. A lower than optimal incubation temperature may negatively affect aspects of nestling physiology, such as body growth and energy metabolism. However, the long-term effects of sub-optimal incubation temperature on morphology and physiology are not well understood. In a previous study, we showed that zebra finches from eggs incubated at a low temperature (35.9°C) for 2/3 of the total incubation time suffered a lower post-fledging survival compared to individuals that had been incubated at higher temperatures (37.0 and 37.9°C). In the present study, we investigated whether these variations in incubation temperature could cause permanent long-lasting differences in body mass, body size, or basal metabolic rate. Furthermore, we tested whether the observed differences in survival between treatment groups would be reflected in the rate of physiological deterioration, assessed through oxidative damage and decreased metabolic rate with age (i.e. ‘metabolic aging’). Incubation temperature did not significantly affect embryonic or nestling body growth and did not influence final adult body mass or body size. Nor was there any long-term effect on basal metabolic rate. Birds from eggs incubated at the lowest temperature experienced an accumulation of oxidative damage with age, although this was not accompanied by an accelerated rate of metabolic aging. The present results suggest that the low survival in these birds was possibly mediated by increased oxidative stress, but independent of body growth and the basal metabolic rate.

Marketing Fed Cattle Based on Expectations of the Underlying Carcass Value Dynamics

Fed cattle profitability is determined by complicated dynamic processes of body growth, carcass development, and seasonal prices. A structural model is constructed to contend with all these dynamic processes to predict optimal market timing. Informed simulations are conducted and compared to those observed in the data, as well as to a previous model ignoring the evolution of carcass value. The results indicate that significant improvements to profitability are attainable with the new method. The results also indicate the opportunity cost of not accounting for carcass value, even with error, is more severe than when these dynamics are ignored.

The body weight performance of indigenous indonesian chickens in the grower phase

Body weight is a critical parameter to monitor in chickens due to its correlation with better performance during the production phase. Hence, this study aimed to present an overview of the body weight performance of indigenous Indonesian chickens in the grower phase. The study was conducted in Gunung Kidul, Yogyakarta. Data of body weight performance data of 227 Merawang, 157 Murung Panggang, and 416 KUB chickens in the grower phase were collected. These weights were measured 4 times at 6, 8, 10, and 12 weeks while rearing the chickens in battery cages in a closed house under similar management. The result showed that the Murung Panggang chickens at each age had the highest body weight and uniformity value (P<0.05), followed by Merawang and KUB. The body growth curve of the Merawang, Murung Panggang, and KUB chickens at the 6th week showed similar weights, ranging between 400-600 g. However, at the 8th, 10th, and 12th weeks, the Merawang and Murung Panggang chickens had higher body weight performance. Therefore, this study suggested that Merawang and Murung Panggang chickens may have a greater potential to attain higher final body weights.