Effects of Electromagnetic Fields on the Growth of Nestling American Kestrels

AbstractWe studied nestling American Kestrels (Falco sparverius) in a laboratory setting to determine whether exposure to electromagnetic fields (EMFs) affected their growth. Captive nestlings were raised by their parents under control or EMF conditions similar to those occurring near transmission lines in the wild. Nestlings also were exposed to EMFs as embryos when incubated by their parents. Measurements of body mass, and lengths of tarsi, antebrachia, and feathers were taken every three days after hatching. EMF exposure affected the growth of female and male nestlings. EMF nestlings and fledglings were heavier and had longer tarsi. The periods of maximal weight gain and antebrachial growth were delayed in EMF males compared to controls, although EMF males were heavier and had similarly long antebrachia to controls by 21 days of age. Growth of ninth primaries and central rectrices of nestlings were unaffected by EMF exposure. Growth patterns of male and female kestrel nestlings were similar to those previously reported for this species, although the periods of maximal weight gain and bone growth did not occur earlier in EMF males than females as it did in controls.

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Possible Epigenetic Origin of a Recurrent Gynandromorph Pattern in Megachile Wild Bees

Insects ◽

10.3390/insects12050437 ◽

2021 ◽

Vol 12 (5) ◽

pp. 437

Author(s):

Daniele Sommaggio ◽

Giuseppe Fusco ◽

Marco Uliana ◽

Alessandro Minelli

Keyword(s):

Current Knowledge ◽

Sex Differentiation ◽

General Pattern ◽

Body Parts ◽

Wild Bees ◽

Male And Female ◽

Female Phenotype ◽

In The Wild ◽

Gene Transcripts ◽

Individual Body

Gynandromorphs, i.e., individuals with a mix of male and female traits, are common in the wild bees of the genus Megachile (Hymenoptera, Apoidea). We described new transverse gynandromorphs in Megachile pilidens Alfkeen, 1924 and analyze the spatial distribution of body parts with male vs. female phenotype hitherto recorded in the transverse gynandromorphs of the genus Megachile. We identified 10 different arrangements, nine of which are minor variants of a very general pattern, with a combination of male and female traits largely shared by the gynandromorphs recorded in 20 out of 21 Megachile species in our dataset. Based on the recurrence of the same gynandromorph pattern, the current knowledge on sex determination and sex differentiation in the honey bee, and the results of recent gene-knockdown experiments in these insects, we suggest that these composite phenotypes are possibly epigenetic, rather than genetic, mosaics, with individual body parts of either male or female phenotype according to the locally expressed product of the alternative splicing of sex-determining gene transcripts.

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Intraskeletal bone growth patterns in the North Island Brown Kiwi ( Apteryx mantelli ): Growth mark discrepancy and implications for extinct taxa

Journal of Anatomy ◽

10.1111/joa.13503 ◽

2021 ◽

Author(s):

Christian T. Heck ◽

Holly N. Woodward

Keyword(s):

Bone Growth ◽

Growth Patterns ◽

Growth Mark ◽

The North

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Cancer cluster among young Indian adults living near power transmission lines in Bom Jesus do Tocantins, Pará, Brazil

Cadernos de Saúde Pública ◽

10.1590/s0102-311x1998000700016 ◽

1998 ◽

Vol 14 (suppl 3) ◽

pp. S161-S172 ◽

Cited By ~ 8

Author(s):

Sergio Koifman ◽

Iara Ferraz ◽

Trajano S. Viana ◽

Carmen L. P. Silveira ◽

Maria T. D. Carneiro ◽

...

Keyword(s):

Electromagnetic Fields ◽

Transmission Lines ◽

Power Transmission ◽

Organophosphorus Pesticides ◽

Daily Activities ◽

Blood Levels ◽

Continuous Exposure ◽

Power Transmission Lines ◽

Cancer Cluster ◽

Hair Samples

A case study was carried out to explore the occurrence of a cancer cluster in 1992 among young indian adults living in an Amazonian village near two 500 kV power transmission lines that began operating a decade ago. Current blood levels of DDT and organophosphorus pesticides and metal levels in hair samples were measured. Extremely low magnetic field exposure was determined during current daily activities carried out by the Indian villagers. Taking into account the cancer incidence rates in different Brazilian cities, the probability of the occurrence of this cluster by chance was considered remote (p< 0.003, Poisson distribution). High blood levels of p,p'-DDT (median levels ranging from 26 to 58 ppb) were observed. As a whole, this community showed a pattern of low exposure to organophosphorus pesticides, and high recent exposure was only observed in a few blood samples. Continuous exposure to extremely low electromagnetic fields originated in the power transmission lines (which reached 95.0 mG under the lines) was observed on several opportunities during daily activities carried out by Indian villagers. Further observational studies should evaluate the interaction between exposure to extremely low electromagnetic fields and prior exposure to tumor initiators in cancer development.

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The lambing period of mountain sheep: synthesis, hypotheses, and tests

Canadian Journal of Zoology ◽

10.1139/z82-001 ◽

1982 ◽

Vol 60 (1) ◽

pp. 1-14 ◽

Cited By ~ 62

Author(s):

Fred L. Bunnell

Keyword(s):

Body Weight ◽

Thermal Stress ◽

Weight Gain ◽

Female Body ◽

Extreme Environments ◽

Growth Patterns ◽

Central Tendency ◽

Seasonal Growth ◽

Early Weight Gain ◽

Definition Of

Data on lambing periods from 30 populations of North American mountain sheep are reviewed. Among all populations lambing begins later and duration is shorter at more northern altitudes (p < 0.00006). Correlations are enhanced (p < 0.00003) when latitude is replaced by a phenological index incorporating altitude. Termination of lambing is not correlated with latitude or with phenological index. Two broad patterns are evident. Populations feeding on vegetation of less predictable growth patterns ("desert type") have lengthy lambing seasons; populations feeding on vegetation exhibiting more predictable growth patterns ("alpine type") have shorter lambing seasons, typically two oestrous cycles in length. Definition of "types" by latitude or sheep taxonomy reveals significant differences in lambing periods, but correlations are enhanced when "types" are defined on the basis of habitat.Among taxa, birth weights are correlated with female body weight (rs = 0.87). Birth weights are heavier in extreme environments, seasonal growth patterns are expressed better in the alpine type, and early weight gain is most rapid in the northernmost subspecies. All populations show a strong central tendency with regard to peak lambing (17 May ± 6.8 days). Departures from that tendency respond more to predictability of vegetation than to thermal stress or predation pressure.

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Effects of Bisphenol-A (BPA) and black seed oil on body weight, lipid profile and serum glucose in male and female mice

10.33109/bjvmjj19lam2 ◽

2019 ◽

Vol 17 (1) ◽

Author(s):

K. M. Sujan ◽

E. Haque ◽

M. S. Rakib ◽

M. I. Haque ◽

A. Mustari ◽

...

Keyword(s):

Body Weight ◽

Weight Gain ◽

Bisphenol A ◽

Lipid Profile ◽

Seed Oil ◽

Serum Glucose ◽

Male And Female ◽

Female Mice ◽

Black Seed ◽

Black Seed Oil

Background: Bisphenol-A [BPA, 2, 2-bis (hydroxyphenyl) propane] is widely used in the manufacture of polycarbonate plastic, water bottles, feeders , baby bottles, epoxy resins and inside coating in metallic food cans. Black seed oil (BSO) (Nigella sativa) commonly known as black cumin, reported to be beneficial in function of various systems in the body. The study was carried out to investigate the effect of BPA and BSO on body weight, lipid profile and serum glucose in male and female mice. Methods : A total of thirty (15 male and 15 female) Swiss Albino mice (Mus musculus), aged 25-28 days with an average body weight of 27.4±1g were randomly divided into 3 groups consisting 5 mice in each for each sex. Group A served as vehicle control. Group B was administered BPA @ 50 mg/kg bw daily, while group C received both BPA @ 50 mg/kg/day and BSO @ 1ml/kg/day respectively. Results: Data revealed that BPA treated mice showed slight increase in body weight gain while BSO controlled the weight gain in BPA treated mice. Cholesterol and LDL values were significantly (p<0.01) increased and Triglycerides value was significantly (p<0.01) decreased in BPA-treated mice without significant alterations in HDL value. BPA & BSO treated female mice showed significant (p<0.01) decreased in cholesterol, triglycerides and LDL values. BPA reduced the blood glucose level and addition of BSO had synergistic effects of glucose utilization. Conclusions: It can be concluded that BPA is one of the potential risk factors for hyperlipidemia and obesity. These harmful effects could be alleviated by the ingestion of black seed oil.

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Changes in African Elephant (Loxodonta africana) faecal steroid concentrations post-defaecation

Bothalia ◽

10.4102/abc.v48i2.2312 ◽

2018 ◽

Vol 48 (1) ◽

Cited By ~ 6

Author(s):

Judith T. Webber ◽

Michelle D. Henley ◽

Yolanda Pretorius ◽

Michael J. Somers ◽

Andre Ganswindt

Keyword(s):

Reproductive Function ◽

Loxodonta Africana ◽

African Elephant ◽

Sample Collection ◽

Male And Female ◽

Freeze Dried ◽

Metabolite Concentrations ◽

Endocrine Status ◽

In The Wild ◽

Sun And Shade

Background: Faecal hormone metabolite measurement is a widely used tool for monitoring reproductive function and response to stressors in wildlife. Despite many advantages of this technique, the delay between defaecation, sample collection and processing may influence steroid concentrations, as faecal bacterial enzymes can alter steroid composition post-defaecation.Objectives: This study investigated changes in faecal glucocorticoid (fGCM), androgen (fAM) and progestagen (fPM) metabolite concentrations in faeces of a male and female African elephant (Loxodonta africana) post-defaecation and the influence of different faeces-drying regimes.Method: Subsamples of fresh faeces were frozen after being dried in direct sun or shade for 6, 20, 24, 48 and 72 h and 7 and 34 days. A subset of samples for each sex was immediately frozen as controls. Faecal hormone metabolite concentrations were determined using enzyme immunoassays established for fGCM, fAM and fPM monitoring in male and female African elephants.Results: Hormone metabolite concentrations of all three steroid classes were stable at first, but changed distinctively after 20 h post-defaecation, with fGCM concentrations decreasing over time and fPM and fAM concentrations steadily increasing. In freeze-dried faeces fGCM concentrations were significantly higher than respective concentrations in sun-dried material, which were in turn significantly higher than fGCM concentrations in shade-dried material. In contrast, fAM concentrations were significantly higher in sun- and shade-dried faeces compared to freeze-dried faeces. Higher fPM concentrations were also found in air-dried samples compared to lyophilised faeces, but the effect was only significant for sun-dried material.Conclusion: The revealed time restriction for collecting faecal material for hormone monitoring from elephants in the wild should be taken into account to assure reliable and comparable results. However, if logistics allow a timely collection, non-invasive hormone measurement remains a powerful and reliable approach to provide information about an elephant’s endocrine status.

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Rapid Weight Gain Following Weight Cutting in Male and Female Professional Mixed Martial Artists

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2020-0369 ◽

2021 ◽

pp. 1-9

Author(s):

Kadhiresan R. Murugappan ◽

Ariel Mueller ◽

Daniel P. Walsh ◽

Shahzad Shaefi ◽

Akiva Leibowitz ◽

...

Keyword(s):

Weight Loss ◽

Weight Gain ◽

Body Mass ◽

Martial Arts ◽

Female Athletes ◽

Rapid Weight Loss ◽

Mixed Martial Arts ◽

Rapid Weight Gain ◽

Male And Female ◽

Small Series

Rapid weight loss or “weight cutting” is a common but potentially harmful practice used in mixed martial arts competition. Following the official weigh-in, competitors refeed and rehydrate themselves in a process known as rapid weight gain (RWG) to realize a potential competitive advantage. While data from surveys and small series have indicated the majority of mixed martial arts athletes engage in rapid weight loss, there is a lack of officially collected data from sanctioning organizations describing its prevalence. The present investigation represents a summary of the data collected between December 2015 and January 2018 by the California State Athletic Commission. In total, 512 professional mixed martial artists (455 males and 57 females) were included. Of these, 503 (98%) athletes gained body mass between weigh-in and their bouts. Total RWG between weigh-in and competition was 5.5 ± 2.5 kg, corresponding to an 8.1% ± 3.6% body mass increase. Total RWG was 5.6 ± 2.5 kg (8.1% ± 3.6%) for males and 4.5 ± 2.3 kg (8.0% ± 3.8%) for females. More than one quarter of men and one third of women gained >10% body mass between weigh-in and competition. Athletes from leading international promotions gained more absolute, but not relative, body mass than those from regional promotions. Our findings indicate RWG is nearly ubiquitous in professional , with a similar prevalence in male and female athletes. Trends based on promotion suggest a larger magnitude of RWG in presumably more experienced and/or successful mixed martial artists from leading international promotions.

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Effect of different levels of digestible lysine on performance, and blood parameters of male and female broilers in the starter period

Proceedings of the British Society of Animal Science ◽

10.1017/s175275620003060x ◽

2009 ◽

Vol 2009 ◽

pp. 221-221

Author(s):

F Alemi ◽

M Shivazad ◽

M Zaghari ◽

H Moravej ◽

A Mahdavi ◽

...

Keyword(s):

Body Composition ◽

Weight Gain ◽

Amino Acid ◽

Blood Parameters ◽

Male And Female ◽

Feed Formulation ◽

Increase Weight Gain ◽

Improve Body Composition ◽

Different Levels ◽

The Ideal

Lysine is the reference amino acid (AA) in the ideal AA ratios for chickens. Feed formulation based on digestible AA has been shown to increase weight gain and feed intake and improve body composition in broilers. Amino acid (AA) in most feed ingredients will not be totally digested, and knowledge of such efficiency is important in formulating diets and will be used to eliminate differences in absorption efficiencies due to feedstuff sources. This study was conducted to evaluate the growth performance and blood parameters of broilers fed various levels of DL (Digestible Lysine) supplemented in diets from day 1 to day 18.

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Effect of long-term undernutrition on male and female rat diaphragm contractility, fatigue, and fiber types

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.4.1540 ◽

1994 ◽

Vol 76 (4) ◽

pp. 1540-1547 ◽

Cited By ~ 15

Author(s):

D. J. Prezant ◽

B. Richner ◽

T. K. Aldrich ◽

D. E. Valentine ◽

E. I. Gentry ◽

...

Keyword(s):

Weight Gain ◽

Fatigue Resistance ◽

Female Rats ◽

Fiber Types ◽

Female Rat ◽

Male And Female ◽

Male And Female Rats ◽

Males And Females ◽

Diaphragm Atrophy

The effects of long-term undernutrition (10 wk) on diaphragm contractility, fatigue, and fiber type proportions were studied in male and female rats. Contractility and fatigue resistance indexes were measured in an in vitro diaphragm costal strip preparation by using direct stimulation at 37 degrees C. Undernutrition allowed for continued growth in males and females but with substantial reductions in weight gain. Relative to control rats of the same sex, final weights were significantly lower in undernourished males (74 +/- 3%) than females (90 +/- 5%), but weight gain was not significantly different between undernourished males (58 +/- 5%) and females (60 +/- 3%). Only in males did undernutrition significantly reduce costal diaphragm weight (to 77 +/- 5% of control). Diaphragm forces, normalized for cross-sectional area, were not significantly different from male or female control values. Fatigue resistance indexes (fatigue/baseline force) were increased at all stimulation frequencies in undernourished males but not in undernourished females. Costal diaphragm atrophy, involving types I and II fibers, occurred in undernourished males but not in undernourished females. In conclusion, despite long-term undernutrition reducing weight gain to similar levels in males and females (relative to control), there was excellent preservation of diaphragm weight, function, and structure in females but, although diaphragm atrophy occurred, there was preserved contractility and increased fatigue resistance in males.

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