Female Body Weight Research Articles

Application of bivariate regression method for estimating the secondary natality in brown hare

Knowledge of reproductive performance of the European brown hare (Lepus europaeus, Pallas, 1778) is an essential condition for planning rational utilization. The direct possibility of estimating the number of leverets is the placental scar counting of the eviscerated females in the hunting bag. A condition for a reliable estimate is a sufficient sample quantity and the timing of sampling. Late sampling leads to a risky and unreliable estimate due to the disappearance of placental scars (amount of reproduction), which will result in under- or over-utilization. The goal of study is to test a method that enables reliable estimation for the amount of reproduction by using individual biological parameters and eliminates the risk resulting from timing. This case report is an attempt to estimate the number of placental scars (born leverets) by using the dried eye lens weight and body weight of fertile females by bivariate linear regression method. Based on the real placental scar number (y), three classes were created: class I: y=1-4; class II: y=5-9; class III: y=9-13 placental scares. The estimated values of the placental scar numbers (y’) using the regression model was only accurate for values belonging to class II. For those belonging to class I the model resulted over-, and to class III an underestimation. The linear regression model using eye lens weight and body weight as independent variables did not result in a reliable estimate of secondary natality for the entire stock in the given situation.

Spawning interactions between hatchery‐reared and wild naturalized rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) in high‐altitude tropical streams, Kenya

AbstractRainbow trout (Oncorhynchus mykiss) is among the most widely translocated fish species in the world. The current study evaluated the spawning interactions between naturalized and wild rainbow trout from two high‐altitude second‐order streams, in Kenya. Data on total length, weight, condition factor, fecundity, fertilization, egg diameter and fry survival were collected on spawning rainbow trout between March and December 2021. Length–weight relationship showed parabolic equations as W = 0.0144L2.900, W = 0.0069L3.0285 and W = 0.00027L3.175 for wild fish stock, hatchery‐reared and wild × hatchery‐reared rainbow trout, respectively. Total fecundity differed significantly among the hatchery‐reared, wild fish and the cross of the two (p < 0.05). The fertilization rate showed significant differences (p < 0.05), with no discernable difference observed between the hatchery‐reared and crossed (wild × hatchery‐reared). There was a positive correlation among the total fecundity to female egg weight, female body weight, fertilization rate and eyed egg survival in all the populations. Relative fecundity was significantly different among the three groups of fish (p < 0.05), but the differences between the hatchery and the crossed (wild × hatchery‐reared) fish showed no significant differences. We recommend the use of crossed (wild × hatchery‐reared) populations for fry production for use in aquaculture as they presented the highest fecundity and gave the best outcome of fry with high survival.

Age-Dependent Changes in the Effects of Androgens on Female Metabolic and Body Weight Regulation Systems in Humans and Laboratory Animals

In recent years, the effects of androgens on metabolic and body weight regulation systems and their underlying mechanisms have been gradually revealed in females. In women and experimental animals of reproductive age, androgen excess can adversely affect metabolic functioning, appetite, and body weight regulation. In addition, excess androgens can increase the risk of metabolic disorders, such as obesity, insulin resistance, and diabetes. These unfavorable effects of androgens are induced by alterations in the actions of hypothalamic appetite-regulatory factors, reductions in energy expenditure, insulin resistance in skeletal muscle, and β-cell dysfunction. Interestingly, these unfavorable effects of androgens on metabolic and body-weight regulation systems are neither observed nor evident in ovariectomized animals and post-menopausal women, indicating that the adverse effects of androgens might be dependent on the estrogen milieu. Recent findings may provide novel sex- and age-specific strategies for treating metabolic diseases.

PSII-4 Effects of Rye or Triticale with or without Crimson Clover on Forage Yield and Quality, and Gestating Beef Female Performance

Abstract The objective was to evaluate the effects of rye or triticale with or without crimson clover on forage yield and quality, and gestating beef female performance. In experiment 1, four cover crop treatments (trt) were randomly assigned to plot (0.49 ha/plot; 6 plots/trt) in a 2×2 factorial design. Treatments included cereal rye or triticale with or without crimson clover. Plots were seeded mid-September (rye or triticale: 101 kg/ha; crimson clover inclusion: 84 kg/ha cereal and 9 kg/ha legume). Treatments were mechanically harvested for haylage at the end of May. Plot yield was determined by total forage mass collection. Prior to ensiling, samples (12/plot) were composited within plot to evaluate forage quality. Data were analyzed using the MIXED procedure of SAS 9.4. Forage yield was greater (P < 0.01) with inclusion of crimson clover than without (3,208 vs. 2,654 kg/ha, respectively). Forage yield was not different (P = 0.17) between cereal type. Crimson clover inclusion reduced dry matter (P < 0.01). Between cereal types, rye had greater (P < 0.01) DM than triticale. Crimson clover inclusion increased CP (P < 0.01; 9.6% vs 8.6%, respectively). Neutral detergent fiber and acid detergent fiber were greater (P < 0.01) in rye compared with triticale. In experiment 2, spring-calving cows and heifers (n = 105; BW = 633 ± 100 kg; gestation = 198 ± 17 days) were randomly assigned to 1 of 5 treatment diets in a 42-day feeding trial to determine feed value of cover crops. Four diets were based on cover crops (60% inclusion) from experiment one with an additional control diet (CON; 85% alfalfa hay and 15% modified wet distillers grains). All treatments were limit fed (11.3 BW∙animal-1∙d-1/). Body weights (BW) and body condition scores (BCS) were assessed at trial initiation and conclusion. Data were analyzed using the MIXED procedure of SAS 9.4. Female final BW and BW change were greater (P < 0.01) in cover crop treatments compared with CON. Body weight change did not differ (P ≥ 0.21) between cereal type or with inclusion of crimson clover. Initial BCS was not different (P ≥ 0.47); however, final BCS was greater (P < 0.01) in cover crop treatments compared with CON. Crimson clover inclusion increased (P = 0.02) BCS change. In summary, inclusion of crimson clover increased forage yield, CP, and female BCS. Although rye cover crops had decreased quality prior to ensiling, there were no differences in cow performance compared with triticale. Substituting cover crops for alfalfa hay resulted in increased cow BW and BCS, suggesting the cover crops evaluated have greater feed value than alfalfa hay.

Impact of high-fat diet and exposure to constant light on reproductive competence of female ICR mice.

Obesity and exposure to light at night are prevalent in modern society and associated with changes in physiology and behavior that can affect a female's ability to support offspring growth during pregnancy and lactation. A 2X3 factor study of ICR mice was conducted to determine the effect of diet [control (CON; 10% fat) or high fat (HF; 60% fat)] and exposure to regular 12 h light:dark cycles (LD) or continuous low (L5) or high (L100) lux of light on gestation length, birth litter size, milk composition and litter growth to lactation day 12. HF diet reduced birth litter size, but increased postnatal d 12 litter weight (P<0.05), whereas constant light tended to increase litter weight (P=0.07). Continuous light increased gestation length, altered dam feed intake, increased serum prolactin and increased final dam and mammary gland weight (P<0.05), while decreasing mammary ATP content and milk lactose (P<0.05). Correlation analysis indicated a positive relationship between final litter weight and mammary size, metabolic stores (e.g. maternal fat pad weight), kcal of feed intake, and gestation length (P<0.05). Although CON mice spent more time eating than HF dams, the calorically dense HF diet was related to greater rates of litter growth to peak lactation. Constant light circadian disrupting effects appear to be confounded by a potential long day photoperiod response exemplified by higher circulating levels of prolactin and increased body and mammary weight of females exposed to these conditions. Other model systems may be better to study the interacting effects of obesity and circadian disruption on reproductive competence.

Growth, sex reversal pattern, and reproductive characteristics of Barramundi (Lates calcarifer) broodstock candidates reared in floating cages

Sex reversal of male to female is a characteristic of barramundi (Lates calcarifer), which is affected by several factors, thereby changing the broodstock population. A study was conducted in floating cages in Langkawi, Malaysia, to determine the weight point at the onset of the sex reversal phenomena. A total of 75 female and 55 male adult individuals (3–4 weeks of age) were sampled from the fish cultured in cages to ascertain their sex at different weights. The water temperature and salinity values were 29.82 °C and 33.12 ppt, respectively. The specimens were classified into twelve bodyweight classes (2.00–8.00 ± 0.5 kg intervals). Female specimen body weight distribution was highest in the 6.01–6.50 kg class (22.6%), followed by the 5.51–6.00 kg and 4.51–5.00 class (13.3%), while male specimen body weight distribution was highest in the 4.51–5.00 kg class (32.1%), followed by the 4.01–4.50 kg class (30.3%). Length-to-weight relationships for females and males of Asian Seabass indicated positive allometric growth. The correlation between body weight and GSI, using Pearson’s correlation, for both sexes, for the male and female barramundi, there was a weak correlation between body weight and GSI, which was 37 and 30%, respectively. Based on the present study’s findings, it can be concluded that sex reversal from male to female in Barramundi largely occurred at 4.57 kg body weight and 66.8 cm total length.

Вариабельность биохимических показателей крови и установление референтных интервалов в доклинических исследованиях. Сообщение 10: монгольские песчанки

Gerbils as a type of laboratory animals are widely used as experimental models in a number of areas of biomedical research. This type of laboratory animals is relatively easy to maintain and handle. They are an alternative test system among rodents such as mice and rats. They are most often used in the study of cerebral ischemia or stroke, behavioral research, aging processes, the development of oncological diseases, as well as the study of para­sitic, viral and bacterial infections, studies of the mechanisms and therapy of epileptic seizures and metabolic disorders such as obesity and diabetes mellitus. The aim of this work was to create a database of reference intervals of biochemical parameters of normal healthy mature Mongolian gerbils with further use in daily routine laboratory practice in preclinical centers. The data that were used to form the reference intervals were obtained from intact animals in “Home оf Pharmacy”. All manipulations and experiments were approved by the bioethical commission. The study involved 20 males and 20 females (non-pregnant excluding the estrous cycle phase) of Mongolian gerbils. The age of the animals corresponded to the range of 6–8 weeks, the body weight of males and females was within 60 g. The levels of the following parameters were determined in the blood serum of animals: creatinine, urea, alanine aminotransferase, aspartateaminotransferase, alkaline phosphatase, cholesterol, triglycerides, total protein, albumin, glucose, total bilirubin, the number of globulins was calculated, as well as the ratio of albumin/globulins. The obtained ranges of males and females had no statistical difference between them. These intervals were analyzed for comparison with other reference intervals of gerbils found in the scientific literature, as well as with ranges of similar indicators characteristic of humans. Norms of biochemical parameters of blood serum of gerbils are an important tool necessary for monitoring animal health during biomedical research, monitoring the dynamics of modeling pathological conditions in animals and studying the safety of new pharmacological agents. An important aspect in preclinical research is the creation of any reference intervals of laboratory animals in each scientific center separately. This is due to a large number of pre-analytical, analytical and post-­analytical features, as well as minimizing the risk of misinterpretation of the data obtained during biomedical research.

Sex-specific differences in metabolic hormone and adipose tissue dynamics induced by moderate low-carbohydrate and ketogenic diet

Low-carbohydrates diets are increasingly used to treat obesity and metabolic disorders. A very low-carbohydrate, ketogenic diet is hard to follow and, due to the very high fat content, linked to severe side effects, like hyperlipidemia and atherogenesis. Therefore, a less restrictive, unsaturated fat-based low-carbohydrate diet appears as a promising alternative. Since neither sex differences, nor their effect on specific metabolic hormones and adipose tissue compartments have been investigated thoroughly in these diets, we aimed to analyze their dynamics and metabolic factors in mice. We found a significant sexual dimorphism with decreased body weight and subcutaneous fat only in males on ketogenic diet, while diminished insulin, elevated ghrelin and FGF-21 were present with a differential time course in both sexes. The non-ketogenic moderate low-carbohydrate diet increased body weight and perigonadal fat in females, but induced leptin elevation in males. Both diets enhanced transiently TNFɑ only in males and had no impact on behavior. Altogether, these results reveal complex sex-dependent effect of dietary interventions, indicating unexpectedly females as more prone to unfavorable metabolic effects of low-carbohydrate diets.

Supplemental feedings affect diet seasonality and niche width in urban Eurasian red squirrels

Abstract Urban environments are novel alternative habitats for wildlife. Anthropogenic food resources such as supplemental feeding (SF) are usually abundant, stable across seasons, and sometimes rich in calories. Although anthropogenic food resources could modify the seasonality and composition of the diets of urban animals, previous studies have been limited to qualitative assessments based on stomach content and food remains. Our study compared diet seasonality and niche width between rural and urban populations of Eurasian red squirrels (Sciurus vulgaris) in Hokkaido, Japan, using direct observation and stable isotope analysis. We found that dietary seasonality was lower in urban populations than in rural populations. The frequency of seed use was higher throughout the year in urban populations than in rural populations, possibly because of excessive seeds by SF in urban squirrels. Additionally, female body weights of the urban population were higher than those of the rural population. However, this was not true for males. Because high body weight can increase reproductive success in females, it is feasible that diet modification could contribute to population growth in urban squirrels. However, no differences in male body weight were observed, possibly due to energy loss caused by intense male–male competition at feeding sites. Our study highlights the importance of studying the multidimensional effects of anthropogenic foods on wildlife.

Reproduction and Production Performance of Swamp Buffalo (Bubalus bubalis) at the Small-Scale Holder Farmer in Sragen Regency, Central Java, Indonesia

This research aimed to determine the performance of swamp buffalo reproduction and production at the small-scale holder farmer in Sragen Regency, Central Java, Indonesia, from June to September 2021. The method used in this research was a survey with a census (complete) sample determination. Data collection applies to interviews, observations and literature studies. Research parameters used in reproductive performance were calving interval (CI), service per conception (S/C), age of the first estrus, age of first birth and postpartum estrus. In contrast, production performance parameters were chest circumference, body length and estimated body weight. The result of research on reproductive performance showed that the average CI were 13.2±0.9 months, S/C 1.25±0.4 time, age of first estrus 2.7±0.6 years, age of first birth 3.7±0.5 years and postpartum estrus were 30–60 days. The result of research on the production of male buffalo body length was 205.3±1.7, and the body length of female buffalo was 127.2±4.3 cm, whereas the chest circumference of female was 205.3±1.7 cm and the chest circumference of the male was 189±2.8 cm. The estimated body weight of females and males were 516.7±7.7 kg and 445.2±11.9 kg. Based on the result of the research, the characteristics of swamp buffalo reproduction and production in Sragen Regency were classified as good.

Effect of supplementary concentrate feeding to lambs on the growth performance and body morphometry

A study was conducted to evaluate the effect of feeding concentrate to suckling lambs on their performance. Experiment comprised 40 day old suckling lambs having 1.56 kg average birth weight, with 20 female and 20 male lambs selected randomly from the flocks of four farmers in village Mundida, Odisha. The male and female lambs were divided into two experimental groups so that each experimental group of 20 lambs consisted of 10 male and equal numbers of females. Group 1 (Control) was maintained on suckling and grazing only, while Group 2, balanced concentrate mixture was supplemented in addition to suckling and grazing. Concentrate was supplemented from 2nd fortnight upto 6th fortnight of age. Body weight, average daily gain were recorded upto14th fortnight ofage. Body measurements were recorded at every fortnight interval. Either of the male or female lambs group body weight did not differ significantly till the 2nd fortnight, while upon concentrate supplementation from 2nd fortnight, the lambs in Group 2 showed significantly higher body weights and average daily gain from 3rd fortnight till the end of observation at every stage (14th fortnight). Body measurements differences between the groups were observed only after commencement of the concentrate supplementation which resulted in higher values for the lambs in Group 2 from 4th or 5th till the last fortnight. Results revealed that supplementation of concentrate to the four weeks old grazing lambs for a period of 8 weeks improved the body weight, weight gain and reduces cost of lamb production.

Growth Performance and Feed Intake Assessment of Italian Holstein Calves Fed a Hay-Based Total Mixed Ration: Preliminary Steps towards a Prediction Model.

The aim of this study was to evaluate the effects of a complete hay-based total mixed ration (TMR) for calves, focusing on their feed intake, animal growth performance, and fecal output, and to develop a preliminary estimation equation for solid feed intake and body weight in Holstein heifer calves. Twenty female Italian Holstein calves (37.14 ± 2.72 kg) born between February and July were studied from the day of birth until 77 days of age. From the fourth day of life, they were fed 3 L/day of pasteurized milk twice daily and supplemented with the same hay-based TMR. The data on feed intake, fecal characteristics, and growth performances were collected and showed that these calves had adequate parameters. Moreover, the data collected was used to create equations to predict body weight and solid feed intake using a mixed model. The goodness of fit of the developed equations was evaluated by coefficients of determinations (R2). The equation obtained shows high R2 (0.98 for solid feed intake and 0.99 for calf weight), indicating the satisfactory precision and accuracy needed to predict female calves' body weight and solid feed intake.

The Histopathological &amp; Behavioral Changes on Mice Experimentally Infected with Toxoplasma Gondii

Toxoplasmosis is one of the most important and common zoonotic diseases worldwide with an infection rate ranging between 20-80% of the world’s population. The affecting in a wide range of mammals, including humans, causes significant disease effects on human health and economic animals. The parasite has an amazing ability to spread within the host’s body and uses various strategies to overcome the blood-brain barrier, with the ability to exist for life within the cells of the infected host. The current study aimed at following up the histopathological changes in the brain of mice experimentally infected with toxoplasmosis. A placenta samples were collected from Al-Salam Teaching Hospital in Mosul, and the parasite was isolated and injection of 100 tissue cyst into the peritoneal cavity of laboratory mice. The animals were divided into three groups, and the mice were dissected after 21, 30 and 40 days of infection period in order to study histopathological changes in the cortex, hippocampus and amygdala. The results of the numbers of parasite cysts in the hippocampus, amygdala and cortex showed an increase in the number of parasite cysts in the cortex compared with the hippocampus and amygdala, the histological sections showed in addition to vacuolar degenerative changes and Apoptosis. After 30 days of infection, the results showed a decrease in body weight in males. The histological sections showed necrosis of the granular cell layer, edema around the nerve axons. The results of the third group, after 40 days of infection, showed a decrease in body weight in males and females compared with the control group and an increase in brain weight in males. The histological sections showed the loss of nuclei in the cells of the basal medial nuclei, vacuolar degeneration, in addition to the presence of vacuolization.

Growth rate of red fox puppies of Vyatka fire type

Purpose: assessment of the dynamics of the growth of the red fox in the process of its ontogenetic development.Materials and methods. The article describes and analyzes the body weight and linear body measurements of females and males of the red fox of the Ognivka Vyatskaya type in postnatal ontogenesis. The research was carried out in the Vyatka farm (Kirov region). The animals were kept in the same conditions, fed in accordance with age and physiological condition. Linear measurements and weighting were performed at 3, 4, 5, 6 and 7 months of age. Growth indicators were fox body weight, body length, snout, head and tail, girth and height of the chest, snout width, length and girth of the front and hind legs.Results. As a result of the studies, periods of intensive puppy growth were identified. The maximum increase in body weight and linear measurements is observed from 3 to 4 months of age, when intensive growth and development of the animal organism is observed. Throughout the study, the coefficient of body weight variation (CV) was maximal compared to linear body measurements and ranged from 6% in 3-month-old puppies to 17% in 6-month-old animals, which makes it possible to consider body weight as an individual indicator of puppy development. All linear measurements at all study timelines had a coefficient of variation (CV) below 10% (ranged from 1 to 8%), that is, one can judge the weak degree of variability of the studied features. Also, during all study periods, sexual dimorphism is visible, males significantly exceeded the size and body weight of females in all studied parameters (p &lt; 0.005).Conclusion. The dynamics of the growth and development of red fox puppies of the Ognivka Vyatskaya type were revealed. Age-related changes in the exterior parameters of young red foxes have been studied.

Abstract GS.11: Exercise Therapy During Doxorubicin Treatment Provides Sex-specific Cardioprotection

Moderate-intensity exercise is routinely prescribed to patients with cardiovascular diseases to improve cardiac function. It has also been recommended in patients undergoing anti-cancer chemotherapy to attenuate cardiotoxic effects. We recently identified that moderate endurance exercise in healthy mice causes the remodeling of cardiac physiology in a sex-specific manner. Therefore, we hypothesized that exercise therapy applied during doxorubicin chemotherapy would produce sex-specific cardioprotection. Male and female mice were divided into three groups, 1) sedentary control, 2) DOX - doxorubicin treated at 5 mg/kg/week for 6 weeks, and 3) EXDOX - 2 weeks of forced treadmill running for 2 weeks before DOX + exercise for an additional 6 weeks. Mouse health was tracked daily. Total body weight, echocardiography, and electrocardiography were assessed every 2 weeks. At the end of the protocol, triple parametric optical mapping was performed to determine the remodeling of cardiac metabolism-excitation-contraction coupling (MECC). DOX treatment increased morbidity and reduced total body weight in both males and females. DOX-induced action potential duration (APD) prolongation in both sexes and, additionally, in males alone, increased anisotropic ratio of conduction (index for arrhythmogenicity) and rise time of calcium transients (CaRT). In EXDOX mice, the onset of morbidity was delayed in both males and females compared to DOX mice. Total body weight in male EXDOX mice, but not females, was further reduced compared to DOX treatment alone. Echocardiography revealed increased LV wall thickness in male and female EXDOX mice vs DOX, while stroke volume was reduced in females alone. Next, DOX-induced APD prolongation was prevented in EXDOX females but not males. Furthermore, DOX-induced increase in CaRT was further increased in EXDOX males, in addition to increased calcium transient duration and reduced calcium decay constant. Taken together, these data suggest significant sex dimorphism in cardiac adaptation to DOX treatment and exercise therapy during DOX treatment. Female mice undergoing exercise therapy during DOX treatment demonstrated greater cardioprotection and attenuation of MECC remodeling.

Morphological and morphometric features of indigenous chicken in North Shewa zone, Oromia regional state, Ethiopia

This study was conducted in the Kuyu and Girar Jarso districts of north Shoa Zone Oromia regional state, Ethiopia, to generate information on the morphological and morphometric characterization of local chicken ecotypes. Multi-stage purposive random sampling technique was used to collect the data. Morph metric data were collected on body weight and other linear measurements and analyzed using the statistical analysis system’s generalized linear model (GLM) procedures. A total of 576 (192 male and 384 female) chickens were considered for qualitative and quantitative traits studies. The results showed that all indigenous chicken in the study area possesses normal feather morphology where, as 99.5% normal and 0.5% crest feather distribution were found. The dominant skin color was yellow, 59.2%, followed by white, 31.6%. With regard to shank color, the yellow color was the dominant (47.6%), followed by white (29.3%) and gray (16.7%). Red (13%), white (11.8%), and Kohima (11.1%) were the predominant plumage colors observed in the study area. The overall mean of body weight, chest circumference, wing span, body length, and shank length for males and females were 1.7 and1.2 kg, 28.7 and 27 cm, 40.4, 39.4, 37.5, 35.3, 8.4 and 8.2 cm respectively. In the present study, morphological and phenotypical variations have been observed among the indigenous chicken populations; hence, an in-depth molecular evaluation is needed to show the level of genetic variation and relationship among them.

Population structure and reproductive dynamics of the ridged swimming crab Charybdis natator in the southern Taiwan Strait of China: significant changes within 25 years

The ridged swimming crab Charybdis natator (Portunidae) is a commercially important crustacean species in China. The purpose of this study is to compare its population structure and reproductive pattern within the same fishing area (the southern Taiwan Strait) from two datasets over 25 years; one from 1994−1996 (the early years of the C. natator fishery) and the other from 2019. The overall sex ratio (male:female) changed from a male bias (1:0.76, p &amp;lt; 0.01) in 1994−1996 to a female bias (1:1.38, p &amp;lt; 0.01) in 2019. Male body sizes (carapace width, CW) were significantly larger than those of females in both datasets (p &amp;lt; 0.05). The average CW and body weight (BW) of males and females in 2019 were significantly smaller (p &amp;lt; 0.01) and lighter (p &amp;lt; 0.01) than those in 1994−1996. The maximum body size and the proportion of large-sized individuals (CW &amp;gt; 10 cm) decreased dramatically over 25 years. One spawning peak season was identified from each dataset, i.e., March−August 1994−1996 and February−April 2019, revealing a 1-month shift. The minimum body sizes for female maturation (carrying eggs) were 6.9 cm CW in 1994−1996 and 6.1 cm CW in 2019, an 11.6% reduction over 25 years. For the first time, the CW at 50% female maturation, the relationship between female absolute fecundity and CW, and egg diameters were obtained from the 2019 dataset, which can be applied in the future comparisons. Recent studies have revealed a consistent spawning peak in February–April for several commercially important crabs in the southern Taiwan Strait. These findings should be considered in crab fishery management. Furthermore, both fishery- and environment-associated factors influencing crustacean population structure and reproductive dynamics merit further investigation.

Leptin, but not Estradiol, Signaling in PACAP Neurons Modulates Puberty Onset

Abstract The adipose-derived hormone leptin critically modulates reproductive function, such that its absence results in hypothalamic hypogonadism. Pituitary adenylate cyclase-activating polypeptide (PACAP)-expressing neurons are potential mediators of leptin's action on the neuroendocrine reproductive axis because they are leptin-sensitive and involved in both feeding behavior and reproductive function. In the complete absence of PACAP, male and female mice exhibit metabolic and reproductive abnormalities, yet there is some sexual dimorphism in the reproductive impairments. We tested whether PACAP neurons play a critical and/or sufficient role in mediating leptin's effects on reproductive function by generating PACAP-specific leptin receptor (LepR) knockout and rescue mice, respectively. We also generated PACAP-specific estrogen receptor alpha knockout mice to determine whether estradiol-dependent regulation of PACAP was critically involved in the control of reproductive function and whether it contributed to the sexually dimorphic effects of PACAP. We showed that LepR signaling in PACAP neurons is critically involved in the timing of female, but not male, puberty onset, but not fertility. Rescuing LepR-PACAP signaling in otherwise LepR-deficient mice was unable to rescue the reproductive deficits observed in LepR null mice but led to a marginal improvement in body weight and adiposity in females. Finally, PACAP-specific estrogen receptor alpha knockout did not lead to any changes in body weight or puberty onset compared with control mice. These data highlight that PACAP is a critical mediator of some of leptin's, but not estradiol's, influence on puberty onset in females, but is not critically involved in relaying leptin's effects in males or in adult females.

Репродуктивная экология бесхвостых амфибий: влияние внутренних и внешних факторов

This research paper examines the influence of internal factors (female body weight, body condition) and external ecological factors on the reproductive parameters of females, as well as on the reproductive ecology of adult individuals of anuran amphibians. Among the most significant reproductive characteristics of females are the number of eggs in a clutch, the proportion of reproductive products to female body weight (contribution to reproduction), and the average weight of eggs. The body weight of the female and the ecological (meteorological) conditions of her activity during the year preceding spawning, as well as the hibernation conditions, have the greatest impact on the quantitative expression of these parameters. The proportion of reproductive products to female body weight in anuran amphibians usually ranges from 13 to 30%. Climate warming can directly affect the reproductive parameters of females, the survival of metamorphs, and the phenology of the spawning period.

The influence of the water-salt extract of the medicinal leech Hirudo verbana Carena, 1820 on the general course of embryogenesis in rats after intraperitoneal administration

Background. The increase in infectious and non-infectious diseases occurrence during pregnancy prompts scientists to search for substances that can fight these ailments. This especially applies to natural substances that have virtually no side effects. These include substances obtained from medicinal leeches. These substances have a wide range of therapeutic effects; as to their practical use, all preclinical studies must be completed. This particularly refers to the presence of an embryotoxic effect. The aim of this work was to investigate the effect of the water-salt extract of the medicinal leech Hirudo verbana Carena, 1820 on the general course of embryogenesis in rats when administered intraperitoneally. Materials and Methods. The work was performed on female non-linear white rats. Two experimental groups of animals were injected intraperitoneally with a water-salt extract of the medicinal leech at a concentration of 5 μg/g of the animal, in a volume of 0.5 mL, three times before mating and three times during pregnancy every 3 days. Two control groups were injected intraperitoneally with physiological saline according to the same scheme as the experimental groups. Subsequently, one of the control and experimental groups underwent euthanasia, dissection of the abdominal cavity and uterine horns on the 20th day of pregnancy. We analyzed the total number of corpora lutea of pregnancy, the number of live and dead fetuses. Fetuses were weighed, examined for the presence of skin hematomas, mutilations, and external abnormalities in the develop­ment of internal organs. The other two groups of control and experimental animals were left until the offspring were born. Then the females of both groups were weighed, and their general condition was assessed. Newborn rats were examined, weight and body length were determined, mortality was recorded from the beginning of birth to 15 days, the presence of skin hematomas, mutilations, and external anomalies of the development of internal organs were checked. Results and discussion. The study established that the intraperitoneal injection of a water-salt extract of a medicinal leech before and during pregnancy in female rats does not cause any toxic effect during embryogenesis and at the early stages of post-embryonic ontogenesis. During the external examination of fetuses and offspring in both groups, no developmental anomalies were noted, all organs in both groups were of normal topography and size. The number of subcutaneous hematomas in the experimental group of fetuses compared to the control group decreased by an average of 50%, postnatal mortality decreased by an average of more than 3 times, as well as an increase in body weight in females, an increase in body weight and body length in the fetus and offspring in the early post-embryonic period ontogenesis (p &lt;0.05). Conclusion. Intraperitoneal administration of a therapeutic dose of a water-salt extract of the medicinal leech to female rats before and during pregnancy, after every three days, does not have any toxic effect on the course of embryogenesis and later in early post-embryonic ontogenesis.