scholarly journals The mathematical model for forecasting the accumulation of heavy metals in pig production

Author(s):  
О. Chala ◽  
О. Chaly ◽  
S. Nagorny

The results of research represent the impact of extensive doses of heavy metals such as lead and cadmium in store pigs bodies. Heavy metals were fed jointly and individually in the doses exceeding the maximum allowable concentrations in the fodder by 10 and 20 times. Therefore, the process of intoxication of the biological object (a swine) by heavy metals is modeled in a way similar to that, which might occur as the result of environmental pollution. The study was performed in order to determine the targets and the extent of the impact of heavy metals exerted upon the body weight, weight of inner parts of the animal body, and the incorporation rate of heavy metals in the swine breeding products. Statistical processing of the obtained data allowed developing mathematical models and determining the correlational relationships between the aspects under investigation. It is determined that heavy metals exert an essential negative impact upon the rate of animal growth and the power of influence increases with the dose. It is also confirmed by a high value of correlational relationship between these parameters (the correlation coefficient (r) is 0.854). Thus, the body weight of swine during the latter of I-II stagesdecreased by 5.5 to 14.8% as it was compared to the control under the influence of hemotoxic substances. The extent of the impact was also dependent upon the toxin itself. Thus, the largest negative effect was observed both under the impact of cadmium only and of cadmium and lead taken together. The highest accumulation of heavy metals was observed in the liver and kidneys, whereas the lowest – in the muscles. The built regression equations showed that increasing of the dose of the relevant element in the fodder exerted the main impact on concentration of cadmium and lead in the body and meat. The content of cadmium in the fodder exerted an impact upon concentration of lead in the meat – with the increase of cadmium concentration the content of lead in the meat decreased. The results of the studies provide an overview of the targets and the extent of the impact exerted by heavy metals upon biological objects. The mathematical models may be used for prediction of the impact and the incorporation rate value of the hemotoxic substances in the swine breeding products. Key words: lead, cadmium, swine breeding products, ecocide environmental impact, migration of xenobiotic, mathematical model.

2018 ◽  
Vol 26 (2) ◽  
pp. 128-131 ◽  
Author(s):  
V. M. Kozak ◽  
V. V. Brygadyrenko

After accumulating in plants, lead and cadmium of technogenic origin concentrate in forest litter, thus inhibiting the speed of its microbiological decomposition and causing chronic intoxication of saprophage millipedes which feed on it. The 20-day laboratory experiment described in this article determined the toxic impact of lead and cadmium (at concentrations of 0.3, 3, 30, 300, 3,000 and 30,000 mg/kg of litter) on the body weight of Megaphyllum kievense (Lohmander, 1928) and microbiological decomposition of forest litter. The death rate of M. kievense increased from 10–20% to 40% at 3 and 30 g/kg of lead and to 100% at 30 g of cadmium per 1 kg of litter. Gain in body weight of M. kievense reliably decreased only at 3 g/kg of cadmium (0.71 to 0.20 mg/24-hours). Under the influence of lead, gain in body weight reliably decreased compared to the control already at 100 times smaller concentration (30 mg/kg of substrate – 0.74 to 0.10 mg/24-hours). Under the influence of both cadmium and lead, the decomposition of litter by microorganisms is slowed down only under the highest of the studied concentrations (30 g/kg). The results of the laboratory experiment showed high resistance of M. kievense to lead and cadmium, at levels significantly higher than natural concentrations of heavy metals in technogenically transformed ecosystems.


Author(s):  
Pablo A. Scacchi Bernasconi ◽  
Nancy P. Cardoso ◽  
Roxana Reynoso ◽  
Pablo Scacchi ◽  
Daniel P. Cardinali

AbstractCombinations of fructose- and fat-rich diets in experimental animals can model the human metabolic syndrome (MS). In rats, the increase in blood pressure (BP) after diet manipulation is sex related and highly dependent on testosterone secretion. However, the extent of the impact of diet on rodent hypophysial-testicular axis remains undefined. In the present study, rats drinking a 10% fructose solution or fed a high-fat (35%) diet for 10 weeks had higher plasma levels of luteinizing hormone (LH) and lower plasma levels of testosterone, without significant changes in circulating follicle-stimulating hormone or the weight of most reproductive organs. Diet manipulation brought about a significant increase in body weight, systolic BP, area under the curve (AUC) of glycemia after an intraperitoneal glucose tolerance test (IPGTT), and plasma low-density lipoprotein cholesterol, cholesterol, triglycerides, and uric acid levels. The concomitant administration of melatonin (25 μg/mL of drinking water) normalized the abnormally high LH levels but did not affect the inhibited testosterone secretion found in fructose- or high-fat-fed rats. Rather, melatonin per se inhibited testosterone secretion. Melatonin significantly blunted the body weight and systolic BP increase, the increase in the AUC of glycemia after an IPGTT, and the changes in circulating lipid profile and uric acid found in both MS models. The results are compatible with a primary inhibition of testicular function in diet-induced MS in rats and with the partial effectiveness of melatonin to counteract the metabolic but not the testicular sequelae of rodent MS.


Author(s):  
Андрей Геннадьевич Деменков ◽  
Геннадий Георгиевич Черных

С применением математической модели, включающей осредненные уравнения движения и дифференциальные уравнения переноса нормальных рейнольдсовых напряжений и скорости диссипации, выполнено численное моделирование эволюции безымпульсного закрученного турбулентного следа с ненулевым моментом количества движения за телом вращения. Получено, что начиная с расстояний порядка 1000 диаметров от тела течение становится автомодельным. На основе анализа результатов численных экспериментов построены упрощенные математические модели дальнего следа. Swirling turbulent jet flows are of interest in connection with the design and development of various energy and chemical-technological devices as well as both study of flow around bodies and solving problems of environmental hydrodynamics, etc. An interesting example of such a flow is a swirling turbulent wake behind bodies of revolution. Analysis of the known works on the numerical simulation of swirling turbulent wakes behind bodies of revolution indicates lack of knowledge on the dynamics of the momentumless swirling turbulent wake. A special case of the motion of a body with a propulsor whose thrust compensates the swirl is studied, but there is a nonzero integral swirl in the flow. In previous works with the participation of the authors, a numerical simulation of the initial stage of the evolution of a swirling momentumless turbulent wake based on a hierarchy of second-order mathematical models was performed. It is shown that a satisfactory agreement of the results of calculations with the available experimental data is possible only with the use of a mathematical model that includes the averaged equations of motion and differential equations for the transfer of normal Reynolds stresses along the rate of dissipation. In the present work, based on the above mentioned mathematical model, a numerical simulation of the evolution of a far momentumless swirling turbulent wake with a nonzero angular momentum behind the body of revolution is performed. It is shown that starting from distances of the order of 1000 diameters from the body the flow becomes self-similar. Based on the analysis of the results of numerical experiments, simplified mathematical models of the far wake are constructed. The authors dedicate this work to the blessed memory of Vladimir Alekseevich Kostomakha.


2020 ◽  
Vol 11 (5) ◽  
pp. 489-509
Author(s):  
R. Cheng ◽  
H. Liang ◽  
Y. Zhang ◽  
J. Guo ◽  
Z. Miao ◽  
...  

This study aimed to determine the impact of Lactobacillus plantarum PC170 concurrent with antibiotic treatment and/or during the recovery phase after antibiotic treatment on the body weight, faecal bacterial composition, short-chain fatty acids (SCFAs) concentration, and splenic cytokine mRNA expression of mice. Orally administrated ceftriaxone quantitatively and significantly decreased body weight, faecal total bacteria, Akkermansia muciniphila, and Lactobacillus plantarum, and faecal SCFAs concentration. Ceftriaxone treatment also dramatically altered the faecal microbiota with an increased Chao1 index, decreased species diversities and Bacteroidetes, and more Firmicutes and Proteobacteria. After ceftriaxone intervention, these changes all gradually started to recover. However, faecal microbiota diversities were still totally different from control by significantly increased α- and β-diversities. Bacteroidetes all flourished and became dominant during the recovery process. However, mice treated with PC170 both in parallel with and after ceftriaxone treatment encouraged more Bacteroidetes, Verrucomicrobia, and Actinobacteria, and the diversity by which to make faecal microbiota was very much closer to control. Furthermore, the expression of splenic pro-inflammatory cytokine tumour necrosis factor-α mRNA in mice supplemented with PC170 during the recovery phase was significantly lower than natural recovery. These results indicated that antibiotics, such as ceftriaxone, even with short-term intervention, could dramatically damage the structure of gut microbiota and their abilities to produce SCFAs with loss of body weight. Although such damages could be partly recovered with the cessation of antibiotics, the implication of antibiotics to gut microbiota might remain even after antibiotic treatment. The selected strain PC170 might be a potential probiotic because of its contributions in helping the host animal to remodel or stabilise its gut microbiome and enhancing the anti-inflammatory response as protection from the side effects of antibiotic therapy when it was administered in parallel with and after antibiotic treatment.


2009 ◽  
Vol 38 (6) ◽  
pp. 1081-1087 ◽  
Author(s):  
Vitor Visintin Silva de Almeida ◽  
Augusto César de Queiroz ◽  
Robério Rodrigues Silva ◽  
Fabiano Ferreira da Silva ◽  
Aline Cardoso Oliveira ◽  
...  

This experiment was carried out with the objective of determining the macrominerals (Ca, P, Mg, K and Na) requirements of Nellore steers under grazing. Twenty four Nellore steers (371 ± 14 kg of BW and 26 mo old) were used. Four steers were slaughtered at the beginning of the experiment (reference group), serving as a reference in subsequent study. The remaining 20 animals were weighed and distributed into a completely randomized design with four supplementation levels offer: 0.0 (mineral mixture - control), 0.3, 0.6 and 0.9% of BW, with five replications. The supplements, based on ground corn, soybean meal and/or urea, were previously balanced to achieve an average daily gain of 350, 650 and 850g, respectively, for the different supplementation levels offer. The contents of macrominerals retained in the animal body were determined by regression equations of the macrominerals body content logarithm in function of the empty body weight logarithm (EBW). Net macrominerals requirements for a gain of 1kg of EBW were obtained using the equation Y'= b.10ª.Xb-1, with a and b, respectively, the intercept and the regression coefficient of the prediction equations of macrominerals in the animal body contents for each macromineral considered. The concentrations of all macrominerals, in the empty body weight and gain of the empty body weight, decreased with the increase in the body weight. Total calcium and phosphorus dietary requirements are higher than those recommended in the literature.


Animals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2679
Author(s):  
Lihuai Yu ◽  
Hongmin Li ◽  
Zhong Peng ◽  
Yuzhu Ge ◽  
Jun Liu ◽  
...  

This study examined the impact of early weaning on antioxidant function in piglets. A total of 40 Duroc × Landrace × Large White, 21-day-old piglets (half male and half female) were divided into suckling groups (SG) and weaning groups (WG). Piglets in WG were weaned at the 21st day, while the piglets in SG continued to get breastfed. Eight piglets from each group were randomly selected and slaughtered at 24th-day (SG3, WG3) and 28th-day old (SG7, WG7). The body weight, liver index, hepatocyte morphology, antioxidant enzymes activity, gene expression of antioxidant enzymes, and Nrf2 signaling in the liver of piglets were measured. The results showed that weaning caused decreased body weight (p < 0.01), lower liver weight (p < 0.01), and decreased the liver organ index (p < 0.05) of piglets. The area and size of hepatocytes in the WG group was smaller than that in the SG group (p < 0.05). We also observed that weaning reduced the activity of superoxide dismutase (SOD) and catalase (CAT) (p < 0.05) in the liver of piglets. Relative to the SG3 group, the gene expression of GSH-Px in liver of WG3 was significantly reduced (p < 0.05). The gene expression of Nrf2 in the SG3 group was higher than that in the WG3 group (p < 0.01). The gene expression of NQO1 in the SG7 group was higher than that in the WG7 group (p < 0.05). In conclusion, weaning resulted in lower weight, slowed liver development, and reduced antioxidant enzymes activity, thereby impairing liver antioxidant function and suppressing piglet growth.


2020 ◽  
pp. 442-451
Author(s):  
А.V. Batig ◽  
A. Ya. Kuzyshyn

One of the most important problems that pose a serious threat to the functioning of railways is the problem of freight cars derailment. However, according to statistics, the number of cases of the derailments of freight cars in trains annually grows. Тo prevent such cases, the necessary preventive measures are developed, and to study the causes of their occurrence, a significant number of mathematical models, programs and software systems created by leading domestic and foreign scientists. Studies of such mathematical models by the authors of this work have led to the conclusion that they are not sufficiently detailed to the extent that it is necessary for analyze the reasons of its derailment. At the same time, an analysis of the causes of the rolling stock derailments on the railways of Ukraine over the past five years showed that in about 20 % of cases they are obvious, and in 7 % of cases they are not obvious and implicitly expressed. The study of such cases of rolling stock derailment during an official investigation by the railway and during forensic railway transport expertises requires the use of an improved mathematical model of a freight car, which would allow a quantitative assessment of the impact of its parameters and rail track on the conditions of railway accidents. Therefore, taking into account the main reasons that caused the occurrence of such railroad accidents over the last five years on the railways of Ukraine, the article selected the main directions for improving the mathematical model of a freight car, allowing to cover all the many factors (explicit and hidden) and identify the most significant ones regarding the circumstances of the derailment rolling stock off the track, established on the basis of a computer experiment. It is proposed in the mathematical model of a freight car to take into account the guiding force, the value of which is one of the main indicators of the stability of the rolling stock. The authors of the article noted that not taking into account the influence of the guiding forces on the dynamics of the freight car can lead to an erroneous determination of the reasons for the rolling stock derailment or even to the impossibility of establishing them.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Oumer Sheriff ◽  
Kefyalew Alemayehu ◽  
Aynalem Haile

Abstract Background An exploratory field research was conducted in northwestern Ethiopia, to characterize the morphological features of Arab and Oromo goat populations as an input to design community-based breeding programs. Ten qualitative and nine quantitative traits were considered from 747 randomly selected goats. All data collected during the study period were analyzed using R statistical software. Results Plain white coat color was predominantly observed in Arab goats (33.72%) while plain brown (deep and light) coat color was the most frequent in Oromo goats (27.81%). The morphometric measurements indicated that Oromo goats have significantly higher body weight and linear body measurements than Arab goats. Positive, strong and highly significant correlations were obtained between body weight and most of the body measurements in both goat populations. The highest correlation coefficients of chest girth with body weight for Arab (r  =  0.95) and Oromo (r  =  0.92) goat populations demonstrated a strong association between these variables. Live body weight could be predicted with regression equations of y  =  − 33.65  +  0.89  ×  for Arab goats (R2  =  90) and y  =  − 37.55  +  0.94  ×  for Oromo goats (R2  =  85), where y and x are body weight and chest girth, respectively, in these goat types. Conclusions The morphological variations obtained in this study could be complemented by performance data and molecular characterization using DNA markers to guide the overall goat conservation and formulation of appropriate breeding and selection strategies.


2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Mahsa Maroofi ◽  
Javad Nasrollahzadeh

Abstract Background Intermittent calorie restriction (ICR) is a novel method of dietary restriction for body weight control with the potential to improve obesity-related cardiometabolic markers, but the impact of this diet on subjects with hypertriglyceridemia (HTG) remains unknown. Methods Eighty-eight subjects with overweight or obesity and mild-to-moderate HTG were randomized to the continuous calorie restriction (CCR) group, or ICR group (a very low-calorie diet during 3 days of the week) for 8 weeks (44 patients in each group). Body composition, plasma lipids, glucose, insulin, adiponectin, and liver enzymes were measured at baseline and after 8 weeks. An intention-to-treat analysis was performed. Results The body weight decreased in both groups (4.07 ± 1.83 kg in the CCR group and 4.57 ± 2.21 kg in the ICR group) with no significant difference between the groups. There was no significant difference between the two groups in the reduced amount of fat mass, fat-free mass, and waist circumference. Both groups achieved a significant reduction in plasma triglycerides after 8 weeks (by 15.6 and 6.3% in ICR and CCR groups, respectively) with no difference between treatment groups. HOMA-IR improved significantly in ICR compared to the CCR group (P = 0.03). Plasma glucose, insulin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, liver enzyme, and adiponectin were not different between the two groups. Conclusions The results of this short-term study suggest that three-days a week of the ICR is comparable to a CCR diet for the reduction of triglycerides level in patients with HTG and in the short-term it appears to be more effective than continuous dieting in improving insulin resistance. However, longer-term studies are needed to confirm these findings. Trial registration Trial registration number:NCT04143971.


2020 ◽  
Vol 32 ◽  
pp. 27-43 ◽  
Author(s):  
Sumei Hu ◽  
Lu Wang ◽  
Jacques Togo ◽  
Dengbao Yang ◽  
Yanchao Xu ◽  
...  
Keyword(s):  
The Body ◽  

Sign in / Sign up

Export Citation Format

Share Document