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1.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806989

RESUMO

Mammalian oocytes are surrounded by an extracellular coat called the zona pellucida (ZP), which, from an evolutionary point of view, is the most ancient of the coats that envelope vertebrate oocytes and conceptuses. This matrix separates the oocyte from cumulus cells and is responsible for species-specific recognition between gametes, preventing polyspermy and protecting the preimplantation embryo. The ZP is a dynamic structure that shows different properties before and after fertilization. Until very recently, mammalian ZP was believed to be composed of only three glycoproteins, ZP1, ZP2 and ZP3, as first described in mouse. However, studies have revealed that this composition is not necessarily applicable to other mammals. Such differences can be explained by an analysis of the molecular evolution of the ZP gene family, during which ZP genes have suffered pseudogenization and duplication events that have resulted in differing models of ZP protein composition. The many discoveries made in recent years related to ZP composition and evolution suggest that a compilation would be useful. Moreover, this review analyses ZP biosynthesis, the role of each ZP protein in different mammalian species and how these proteins may interact among themselves and with other proteins present in the oviductal lumen.


Assuntos
Óvulo/citologia , Óvulo/fisiologia , Zona Pelúcida/fisiologia , Animais , Biomarcadores , Comunicação Celular , Evolução Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Mamíferos , Oócitos/citologia , Oócitos/fisiologia , Óvulo/ultraestrutura , Transporte Proteico , Espermatozoides/metabolismo , Zona Pelúcida/ultraestrutura , Glicoproteínas da Zona Pelúcida/genética , Glicoproteínas da Zona Pelúcida/metabolismo
3.
Environ Entomol ; 50(2): 390-398, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33891675

RESUMO

High-temperature events can influence insect population dynamics and could be especially important for predicting the potential spread and establishment of invasive insects. The interaction between temperature and environmental humidity on insect populations is not well understood but can be a key factor that determines habitat range and population size. The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive agricultural pest in the United States and Europe, which causes serious economic damage to a wide range of crops. This insect's range continues to expand. It has recently invaded the Central Valley of California, which has a hotter and drier climate compared with the Eastern United States where this insect is established. We investigated how high-temperature events and relative humidity would impact the survival and reproduction of H. halys. Using incubators and humidity chambers, we evaluated the impact of humidity and short-term (2 d) high-temperature exposure on the survival and development of H. halys eggs, nymphs, and adults. We found that high temperatures significantly reduced H. halys survival. The impact of humidity on H. halys survival was dependent on temperature and life stage. Low humidity decreased first-instar survival but not third- to fourth-instar survival. High humidity increased first instar survival but decreased third- to fourth-instar survival. Humidity did not influence adult or egg survival. We also found that high temperatures decreased H. halys reproduction. Our findings have important implications for understanding the invasive ecology of H. halys and may be used to improve models predicting H. halys range expansion.


Assuntos
Heterópteros , Óvulo , Animais , Europa (Continente) , Umidade , Temperatura
4.
Poult Sci ; 100(3): 100965, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33652534

RESUMO

We studied the correlations between egg geometrical parameters (i.e., egg shape index, sphericity, geometric mean diameter, surface area, and volume) and eggshell qualities, or the organic matrix in eggshell. Eggs were collected from 5 poultry breeds belonging to 3 species (commercial Hy-line Brown Chicken, Shaoxing Duck, Jinding Duck, Taihu Goose, and Zhedong White Goose). The geometrical parameters showed high variation among 3 species of poultry, and even between breeds in the same species. The five geometrical parameters were grouped into 2 sets, one contained shape index and sphericity, the other comprised geometric mean diameter, surface area, and volume. The parameters in the same set can be perfectly fitted to one another. Egg weight, shell membrane weight, and calcified shell weight were significantly correlated with geometric mean diameter, surface area, and volume. In accordance with false discovery rate-adjusted P value, both shell membrane relative weight and calcified shell thickness showed no significant correlations with any of the geometrical parameters. However, the correlations between geometrical parameters and other shell variables (calcified shell weight, shell relative weight, calcified shell thickness uniformity, and eggshell breaking strength) depend on breed. Both constitutive proportions and percentage contents of 3 eggshell matrix components (acid-insoluble, water-insoluble, and both acid and water facultative-soluble matrix) had no effects on egg shape and size. The correlations between the amounts of various shell matrix, egg shape and size depend on breed or species. This study provides a methodology and the correlation between geometrical parameters and eggshell qualities, and between geometrical parameters and organic matrix components in calcified shells.


Assuntos
Casca de Ovo , Aves Domésticas , Animais , Galinhas/anatomia & histologia , Galinhas/classificação , Patos/anatomia & histologia , Patos/classificação , Casca de Ovo/anatomia & histologia , Casca de Ovo/química , Ovos , Gansos/anatomia & histologia , Gansos/classificação , Óvulo , Aves Domésticas/anatomia & histologia , Aves Domésticas/classificação , Especificidade da Espécie
5.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33672019

RESUMO

Putrajeevak (Putranjiva roxburghii Wall.; synonym Drypetes roxburghii (Wall.) Hurus) seeds have been used since ancient times in the treatment of infertility in the Ayurvedic system of medicine in India. In this study, the oil component of Putrajeevak seeds (PJSO) was extracted using the supercritical fluid extraction (SCFE) method using liquid CO2 and the constituents were analyzed using gas chromatography-flame ionized detectorand high-performance thin-layer chromatography. PJSO contained trace amounts of ß-sitosterol with oleic and linoleic acids as the major fatty acid constituents. Male and female zebrafish were mutagenized with N-ethyl-N-nitrosourea (ENU) and fish that produced less than 20 viable embryos were selected for the study. SCFE oil extracts from the P. roxburghii seeds were used in this study to reverse fertility impairment. The mutant fish were fed with PJSO for a period of 14 days and the rates of fertility, conception, and fecundity were determined with wild-type healthy fish as a breeding partner. Treatment with PJSO increased the ovarian follicle count as well as the number of mature eggs, while reducing the number of ovarian cysts. Sperm count as well as sperm motility were greatly enhanced in the ENU-mutagenized male zebrafish when treated with PJSO. The results obtained in this study demonstrate the effectiveness of P. roxburghii seed oil in reversing impaired fertility in both male and female zebrafish models.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Euphorbiaceae/química , Fertilidade/fisiologia , Sementes/química , Peixe-Zebra/fisiologia , Animais , Modelos Animais de Doenças , Ácidos Graxos/análise , Ácidos Graxos/química , Feminino , Fertilidade/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Ovário/fisiologia , Óvulo/fisiologia , Pelve/patologia , Óleos Vegetais/química , Óleos Vegetais/farmacologia , Óleos Vegetais/uso terapêutico , Sitosteroides/análise , Sitosteroides/química , Testículo/efeitos dos fármacos , Testículo/patologia
6.
J Vis Exp ; (169)2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33749672

RESUMO

Current risk assessment strategies for honey bees rely heavily upon laboratory tests performed on adult or immature worker bees, but these methods may not accurately capture the effects of agrochemical exposure on honey bee queens. As the sole producer of fertilized eggs inside a honeybee colony, the queen is arguably the most important single member of a functioning colony unit. Therefore, understanding how agrochemicals affect queen health and productivity should be considered a critical aspect of pesticide risk assessment. Here, an adapted method is presented to expose honey bee queens and worker queen attendants to agrochemical stressors administered through a worker diet, followed by tracking egg production in the laboratory and assessing first instar eclosion using a specialized cage, referred to as a Queen Monitoring Cage. To illustrate the method's intended use, results of an experiment in which worker queen attendants were fed diet containing sublethal doses of imidacloprid and effects on queens were monitored are described.


Assuntos
Agroquímicos/toxicidade , Abelhas/efeitos dos fármacos , Abelhas/fisiologia , Hierarquia Social , Medição de Risco , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Abelhas/embriologia , Comportamento Alimentar/efeitos dos fármacos , Feminino , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Óvulo/efeitos dos fármacos , Reprodução/efeitos dos fármacos
7.
J Insect Sci ; 21(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33585925

RESUMO

One of the most important global problems is protecting food from insect pests. The negative effects of synthetic insecticides on human health led to a resurgence of interest in botanical insecticides due to their minimal ecological side effects. Therefore, the insecticidal potential of hexane, acetone, and methanol extracts of Gnidia kraussiana Meisn roots at 1 and 5g/kg, and neem seed oil (NSO), used as standard insecticide, were evaluated. Ovicidal and larvicidal toxicity was tested by treating freshly laid eggs and larvae at different immature stages of Callosobruchus maculatus (F.). Cowpea (Vigna unguiculata) (L.) Walp seed damage and weight loss were assessed after a storage period of 4 mo. Repellency effects were detected in choice test using a linear olfactometer. All the fractions were toxic to C. maculatus; however, their bioactivities were inversely correlated with products polarity. Extracts proved to be more toxic than the commercial NSO. The acetone extract was more effective against immature stages of C. maculatus than the methanol extract; eggs, first-, and second-instar larvae being the more susceptible. No cowpea seed damage and weight loss were recorded from the seeds treated with hexane and acetone extracts at the dosage of 5 g/kg, after 4 mo of storage. Extracts evoked stronger repellency effects compared with the tested standard insecticide. According to the above, hexane and acetone extracts are good candidates for incorporation in integrated pest management programs for the control of C. maculatus in stored cowpea seeds.


Assuntos
Besouros , Controle de Insetos , Malvales/química , Compostos Fitoquímicos , Extratos Vegetais , Vigna , Animais , Feminino , Larva , Masculino , Óvulo , Extratos Vegetais/química , Pupa , Sementes/crescimento & desenvolvimento , Vigna/crescimento & desenvolvimento
8.
J Insect Sci ; 21(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560361

RESUMO

Pest management of emerging pests can be challenging because very little fundamental knowledge is available to inform management strategies. One such pest, the red-headed flea beetle Systena frontalis (Fabricius) (Coleoptera: Chrysomelidae), is increasingly being identified as a pest of concern in cranberries Vaccinium macrocarpon Aiton (Ericales: Ericaceae). To improve our understanding of this pest and to develop more targeted management programs, we conducted field and laboratory studies to characterize the development, seasonal emergence patterns, and density-dependent plant injury. We found that significantly more flea beetle eggs hatched when exposed to sustained cold treatment between 0 and 5°C for 15 wk than at warmer temperatures, and for shorter and longer cold-period durations. The adults emerged sporadically over the summer, were patchily distributed, fed on both fruit and foliage, and preferentially fed on new plant growth. Using soil cores, we found eggs and larvae located relatively deep (>30 cm) in the soil. These patterns indicate that S. frontalis likely overwinters as eggs, and that targeting the larval stage may be the most effective management approach. Despite the cryptic nature of the larvae, continuing to improve our understanding of this life stage will be critical to optimizing control strategies.


Assuntos
Besouros/fisiologia , Herbivoria , Controle de Insetos , Traços de História de Vida , Vaccinium macrocarpon , Animais , Besouros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Óvulo/crescimento & desenvolvimento , Densidade Demográfica , Vaccinium macrocarpon/crescimento & desenvolvimento , Wisconsin
9.
Animal ; 15(1): 100030, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33579651

RESUMO

Gregarious nesting has often been observed in laying hens, where hens prefer to visit a nest already occupied by other hens over empty nests. This may result in overcrowding of the nests which is considered a welfare issue and, moreover, can increase the economic issue of floor eggs. This study aimed to describe gregarious nesting and spatial behavior in broiler breeders and how this relates to genetic background, fearfulness and mating behavior. Five commercially available genetic lines of broiler breeders were housed in 21 pens of 550 females and 50 males (six pens for lines 1 and 2, five pens for line 3 and two pens for lines 4 and 5) during the ages 20-60 weeks. Every 10 weeks, the plumage condition and wounds were assessed of 50 random hens per pen. Avoidance distance and novel object tests were performed to assess fearfulness at four time points. Distribution of eggs over nests was observed for 6 weeks at the onset of egg production at 26 weeks of age, and use of space was recorded at four time points, while (floor) egg production was noted daily per pen. We found differences between genetic lines over time in plumage condition and prevalence of wounds. Fear of humans was highest at the earliest age tested and did not correlate with general fearfulness as assessed by the novel object test. The distribution of eggs over nests was related to genetic background and was more uneven at the earliest age compared to later ages, and a more uneven distribution was correlated with an increased percentage of floor eggs. Distribution of birds over the litter area differed between the genetic lines, and less use of the litter area was correlated with an increased fear of humans and presence of wounds, suggesting an association with aggressive mating behavior. This difference in distribution of the birds could also explain the correlation between increased presence of wounds and decreased percentage of floor eggs. It is concluded that broiler breeders do show gregarious nesting, which is affected by genetic background. Both increased gregarious nesting and wounds are related to increased floor egg percentage, which should be studied further in broiler breeder research. Genetic selection for even use of the available nests and of the litter and slatted area would therefore support both broiler breeder welfare and performance.


Assuntos
Galinhas , Abrigo para Animais , Animais , Galinhas/genética , Ovos , Feminino , Pisos e Cobertura de Pisos , Oviposição , Óvulo , Reprodução
10.
J Am Vet Med Assoc ; 258(4): 416-424, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33539208

RESUMO

OBJECTIVE: To describe results of analysis of free-catch urine samples collected from Antillean manatees (Trichechus manatus manatus) under human care in the Caribbean. ANIMALS: 32 Antillean manatees in 5 Caribbean oceanaria and rescue centers. PROCEDURES: Urine samples were obtained by opportunistic free catch during physical examination or through the use of operant conditioning procedures. Urinalyses consisted of macro- and microscopic evaluations, biochemical analyses with test strips, and refractometry. Results were compared for manatees grouped on the basis of age, sex, and habitat. RESULTS: Urine samples were typically clear, straw colored, and alkaline (mean pH, 8.0); had a urinoid odor and low specific gravity (mean, 1.010); and had results on qualitative test strips that were consistently negative for the presence of glucose, bilirubin, ketones, proteins, nitrites, RBCs, and WBCs. Microscopically, the mean ± SD number of RBCs and WBCs/hpf was 0.5 ± 0.3 RBCs/hpf and 1.1 ± 1.5 WBCs/hpf. The presence of some epithelial cells and crystals was typical. Spermatozoa were found in urine from 1 of 15 sexually mature males, and parasite larvae and eggs were found in urine from 2 manatees. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the present study yielded the first compilation of baseline urinalysis values in healthy Antillean manatees under human care, which, when combined with physical examination and other diagnostic procedures, can help in monitoring the health of these animals. We encourage the use of free-catch urine collection methods, as used in the present study, for routine urinalyses of manatees under human care in zoos, aquaria, or rescue centers.


Assuntos
Trichechus manatus , Animais , Região do Caribe , Óvulo , Trichechus , Urinálise/veterinária
11.
Animal ; 15(2): 100124, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33573946

RESUMO

Enterotoxigenic Escherichia coli (ETEC) K99 is one of the major pathogens associated with calf diarrhea. The induction of passive immunity in animals by immunoglobulin Y and using probiotics are inexpensive alternatives to antibiotics for the prevention and treatment of a number of bacterial infections, including diarrhea. Hence, the aim of this research was to evaluate the impact of dietary probiotics and ETEC K99-specific egg yolk antibody supplements, alone and in combination with each other, on health and growth parameters, diarrhea incidence and immune stimulation in newborn Holstein calves. One hundred and twenty neonatal calves were allocated randomly into 4 dietary groups (n = 30 per group) received colostrum/milk without any additives (control group), or supplemented with egg yolk powder contained E. coli K99-specific antibody (Ab group; 1 g/day), a commercial probiotic, Hypro-calves (Pro group; 3 g/day), and their combination (Ab+Pro group), from day (d) 1 to d28 of age. Analyses of the growth parameters, feed efficiency, fecal score, and microbiota and immune function were carried out on d0, 14, 21, and 28 of the experiment. Calves in Ab or Ab+Pro group had higher (P < 0.05) average daily gain compared to control and Pro groups during 0-14d. Feed efficiency of calves in Ab and Ab+Pro groups was significantly higher than that in control group during the period of 0-14d; however, no significant differences were observed in 0-28d period. Diarrhea prevalence and fecal score in Ab+Pro group were lower than control group (P < 0.05). Calves in Ab+Pro group had the lowest number of fecal E. coli in comparison to other groups on d28 (P < 0.05). Feeding Ab+Pro supplement increased (P < 0.05) concentrations of blood IgA and serum CD4 compared to the control group. Likewise, calves in Pro group had higher CD4 levels as compared to the control calves (P < 0.05). Serum concentration of interferon-gamma in control group was lower than other groups (P < 0.05). Overall, these data suggest that feeding a combination of probiotic and specific antibody against ETEC to neonate Holstein calves enhances feed efficiency, boosts immunity, and reduces diarrhea prevalence.


Assuntos
Doenças dos Bovinos , Probióticos , Animais , Animais Recém-Nascidos , Bovinos , Diarreia/prevenção & controle , Diarreia/veterinária , Feminino , Sistema Imunitário , Imunoglobulinas , Incidência , Óvulo , Gravidez
12.
Zoolog Sci ; 38(1): 20-25, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33639714

RESUMO

Oviparous, ovoviviparous and viviparous reproduction are interesting subjects for understanding animals' evolutionary pathways and adaptation to their life history and habitat conditions. In this study, we examined the reproductive mode of the ovoviviparous mayfly Cloeon dipterum, particularly comparing embryogenesis between hand-pairing and unmated females' common oviduct. Our study suggested that the high developmental rate of C. dipterum observed in a recent study could be ascribed to their absorption of unfertilized eggs. The developmental rates of hand-paired females were almost 100%, while their egg-bearing numbers were lower than those of virgin females. Thus, such reduced egg numbers suggest the maternal absorption of unfertilized eggs. This trait is thought to have evolved with the ovoviviparous characteristics of C. dipterum. We identified the basis of the irregularity of this species exhibiting such a high (i.e., 100%) developmental rate in our previous recent study.


Assuntos
Desenvolvimento Embrionário , Ephemeroptera/embriologia , Ephemeroptera/fisiologia , Óvulo , Animais , Tamanho Corporal , Embrião não Mamífero , Feminino , Masculino , Oviductos/fisiologia , Ovoviviparidade
13.
Animal ; 15(2): 100109, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33573984

RESUMO

European farms for broiler breeders often have raised slatted areas in front of the nests, but in other regions of the world no raised slatted areas are provided. This study aimed to investigate the effects of a raised slatted area on leg health, mating behaviour and floor laying behaviour. Ten groups of 33 broiler breeder hens and three males were housed in two pen types: with or without a raised slatted area in front of the nests. Each pen had one plastic and one wooden nest. Between 25 and 31 weeks of age, ten marked hens per pen were weighed and assessed weekly on foot pad dermatitis, hock burn and wounds. At the end of week 31, animals were euthanized and bone strength of the tibia and humerus of these individuals was assessed. At 24, 27 and 30 weeks of age, mating behaviour was observed for an hour per pen, noting both numbers of successful and unsuccessful copulations. The number of eggs laid in the nests and on the floor was recorded daily between 20 and 31 weeks of age. Foot pad dermatitis scores were affected by age, but not by pen type. Generally, there were only minor issues with foot pad dermatitis (scores <11 on a 0-100 scale), probably due to the young age of the hens. Body weight was not affected by pen type, while the prevalence of hock burns was too low to analyse and no difference in bone strength was found for the tibia and the humerus. Overall, mating behaviour was less frequent in pens with raised slats than in pens without raised slats (29 ±â€¯2 vs 35 ±â€¯3 times/h) and more frequent at 27 weeks of age than at 24 and 30 weeks of age (38 ±â€¯1 vs 31 ±â€¯4 and 27 ±â€¯2 times/h). The pens with raised slats had a lower percentage of floor eggs than pens without raised slats (11.2 ±â€¯0.4 vs 19.3 ±â€¯0.5%). The wooden nest was preferred over the plastic nest as on average 63% of the eggs were laid in the wooden nest. This study shows that providing raised slats decreases mating behaviour and percentage of floor eggs, although its effects on leg health remain inconclusive.


Assuntos
Galinhas , Abrigo para Animais , Animais , Feminino , Pisos e Cobertura de Pisos , Óvulo , Reprodução
14.
Poult Sci ; 100(2): 1008-1015, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518059

RESUMO

A large number of antimicrobials are used for the treatment of bacterial infections, and the emergence of antimicrobial-resistant Escherichia coli (E. coli) in livestock and the transfer of resistant isolates to humans poses a serious potential risk to public health. In particular, broiler parent stock produce thousands of eggs for commercial broiler chickens and can transfer antimicrobial-resistant bacteria and drug-resistance genes to chicks. This study was conducted to investigate the prevalence and characteristics of third-generation cephalosporin-resistant and extended-spectrum ß-lactamases (ESBL)-producing E. coli isolated from the broiler parent stock in Korea. Among 51 cefotaxime-resistant E. coli isolates, 45 (88.2%) isolates were identified as multidrug resistant and 21 isolates showed phenotypic and genotypic characteristics of CTX-M-producing E. coli. The CTX-M genes CTX-M-14, CTX-M-15, CTX-M-1, and CTX-M-1 were detected in 10, 7, 3, and 1 isolates, respectively. ISEcp1 or IS26 + ISEcp1 were identified upstream of all CTX-M-type genes, and orf477 and IS903 were detected downstream of 9 and 10 CTX-M-type genes, respectively. Thirteen (61.9%) of the 21 CTX-M-producing E. coli isolates harbored class 1 integrons with 4 different gene cassette arrangements. Among the plasmid replicons, CTX-M-1 was located on I1, F, and FIB; CTX-M-14 on F and FII; CTX-M-15 on FII, FIA, and FIB; and CTX-M-65 on FIB. This is the first study to investigate the presence and distribution of third-generation cephalosporin-resistant and CTX-M-producing E. coli isolated from the broiler parent stock level in Korea, and the results indicate that comprehensive surveillance and persistent monitoring systems in broiler parent stock farms are necessary to prevent the dissemination of resistant isolates.


Assuntos
Galinhas/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/metabolismo , Doenças das Aves Domésticas/microbiologia , Animais , Antibacterianos/farmacologia , Cefotaxima/farmacologia , Resistência Microbiana a Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Óvulo , Doenças das Aves Domésticas/epidemiologia , República da Coreia/epidemiologia , beta-Lactamases/genética
15.
Poult Sci ; 100(2): 1142-1153, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518073

RESUMO

The objective of this study was to determine and evaluate the impact of the age and housing system on blood indicators (triacylglycerides, total cholesterol, aspartate aminotransferase, total proteins, albumin, glucose) and physical egg quality parameters (egg weight, shape index and surface area, eggshell proportion, thickness, strength, and color, albumen proportion and index, Haugh units, yolk proportion, index and yolk-to-albumen ratio) in selected native breeds of the Czech Republic (the Czech Golden Spotted hens) and Slovakia (the Oravka hens). Furthermore, the concentration of cholesterol in the yolk was determined. A total of 132 animals were used. There were 60 eggs collected from each breed at each monitored period for the evaluation of egg quality. Blood samples were taken by puncture of a wing vein. The assessments were made when the hens were of 34, 42, and 50 weeks old. Enriched cages and floor pens with litter were used as housing systems. The effects of breed, housing system, and age were observed. Furthermore, interactions among these factors were calculated. The significant effect of housing system was found in total cholesterol (P = 0.098) and aspartate aminotransferase (P = 0.0343) and the significant effect of age in total protein (P = 0.0392). The significant effect of breed (P = 0.0199), housing system (P = 0.0001), and age (P = 0.0001) was found in concentration of cholesterol in the yolk. Regarding the egg quality, the significant effect of breed (P = 0.0001) was found in eggshell color, albumen index and Haugh units, whereas the significant effect of housing system was found in egg weight (P = 0.0002), egg surface area (P = 0.0003), eggshell proportion (P = 0.0460), thickness (P = 0.0216), strength (P = 0.0049), and color (P = 0.0009). The significant effect of age was determined in all parameters except for the eggshell proportion and strength. The results represent an interesting comparison of changes in biochemical blood and egg quality parameters. It is necessary to further evaluate these indicators, especially in other genetic resources of hens, where the data are often nonexisting.


Assuntos
Envelhecimento/fisiologia , Galinhas/fisiologia , Ovos/normas , Abrigo para Animais/classificação , Envelhecimento/sangue , Animais , Galinhas/sangue , Colesterol/análise , Colesterol/sangue , República Tcheca , Casca de Ovo , Gema de Ovo/química , Feminino , Óvulo , Soro , Eslováquia
16.
Poult Sci ; 100(2): 1192-1204, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518077

RESUMO

Ambient conditions during chicken embryogenesis, such as insufficient oxygen or changes in temperature, are expected to cause permanent phenotypic changes and affect their posthatch performance. Decades of genetic selection for high growth rate resulted with various physiological and morphological changes that can affect the broiler fitness under environmental stress. To evaluate the selection effect on responses to environmental challenge during embryonic development, and the long-term implications, we have used a unique genetic line, that was not selected for over 30 yr (since 1986), as control for the modern commercial genetic line. At embryonic day 5 (E5), broiler embryos from these 2 genetic lines were divided into 2 treatments: 1) control; 2) 15% O2 concentration for 12 h/day from E5 through E12 the embryonic period of chorioallantoic membrane formation. Embryos and hatched chicks were characterized for physiological and morphological parameters. Significant differences in relative embryo weight and yolk consumption were found between the 2 lines. The modern line was characterized by a higher metabolic rate and rapid growth, supported by higher hemoglobin levels and hematocrit concentrations, whereas the 1986 line had slower metabolism, lower levels of hematocrit and hemoglobin, higher oxygen volume per 1 g of embryonic tissue indicating higher oxygen availability. Both lines exhibited changes in heart rate, and blood parameters corresponding to cardiovascular system adaptation after hypoxic exposure, seemingly implemented to increase oxygen-carrying capacity to the embryo tissues. Our finding stand in agreement that the genetic selection for high growth rate that led to higher metabolism without a fit of the cardiovascular system, increased the imbalance between oxygen supply and demand.


Assuntos
Embrião de Galinha/crescimento & desenvolvimento , Galinhas/fisiologia , Membrana Corioalantoide/crescimento & desenvolvimento , Hipóxia/veterinária , Oxigênio/metabolismo , Animais , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Feminino , Frequência Cardíaca , Hipóxia/genética , Hipóxia/fisiopatologia , Óvulo , Fatores de Tempo
17.
Zoo Biol ; 40(2): 150-159, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33559914

RESUMO

While we generally understand the optimal ultraviolet B (UVB) environment for the growth and reproduction of female Panther Chameleons Furcifer pardalis, we do not know the relative importance of UVB irradiance and dose for optimal husbandry outcomes. Accordingly, we experimented with Panther Chameleon females to test the hypothesis that UVB dose (irradiance × exposure duration) determines the outcome, regardless of the combination of UVB irradiance and exposure duration generating the dose. We varied UVB irradiance and exposure duration across treatment groups while keeping dose similar and within a range previously documented to result in reproductive success. The growth rate, age of maturity, and measurable vitamin D status were not significantly different among the treatment groups. Individuals in all groups produced viable eggs that successfully hatched. Thus, we found some support for the hypothesis that the UVB dose determines the outcome regardless of UVB irradiance. However, mean egg vitamin D3 concentration and percent hatching were higher in the highest UVB irradiance group, despite similar doses among the three groups. Preliminary field data reveal that this species occupies UV irradiance Zone 4 in Madagascar, the highest zone for reptiles recorded. Only the irradiance of the high UVB irradiance group in our experiment approached this zone and resulted in the best reproductive success. Biosynthesis of vitamin D3 and provisioning to eggs is more efficient when exposure to UVB irradiance is similar to that in their natural environment. Establishing an optimal UVB environment, based on knowledge of the natural UVB environment, is important for the propagation of Panther Chameleons in captivity.


Assuntos
Lagartos/crescimento & desenvolvimento , Lagartos/fisiologia , Reprodução/fisiologia , Raios Ultravioleta , Animais , Colecalciferol/biossíntese , Colecalciferol/efeitos da radiação , Feminino , Madagáscar , Masculino , Óvulo/química , Fatores de Tempo
18.
Int J Mol Sci ; 22(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530555

RESUMO

The number of sources of anthropogenic magnetic and electromagnetic fields generated by various underwater facilities, industrial equipment, and transferring devices in aquatic environment is increasing. These have an effect on an array of fish life processes, but especially the early developmental stages. The magnitude of these effects depends on field strength and time of exposure and is species-specific. We review studies on the effect of magnetic fields on the course of embryogenesis, with special reference to survival, the size of the embryos, embryonic motor function, changes in pigment cells, respiration hatching, and directional reactions. We also describe the effect of magnetic fields on sperm motility and egg activation. Magnetic fields can exert positive effects, as in the case of the considerable extension of sperm capability of activation, or have a negative influence in the form of a disturbance in heart rate or developmental instability in inner ear organs.


Assuntos
Embrião não Mamífero/efeitos da radiação , Desenvolvimento Embrionário/efeitos da radiação , Peixes , Campos Magnéticos , Animais , Permeabilidade da Membrana Celular/efeitos da radiação , Peixes/crescimento & desenvolvimento , Peixes/fisiologia , Larva , Óvulo/efeitos da radiação
19.
Poult Sci ; 100(2): 835-843, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518137

RESUMO

Magnolol is a multifunctional plant polyphenol. To evaluate the effects of magnolol on laying hens in the late laying period, 360 (50-week-old) laying hens were randomly assigned to 4 dietary treatments: a non-supplemented control diet (C), and control diets supplemented with 100, 200, and 300 mg/kg of magnolol (M100, M200, and M300), respectively. Each treatment had 6 replicates with 15 hens per replicate. Results showed that dietary supplementation of 200 and 300 mg/kg of magnolol increased the laying rate and the M200 group had a lower feed conversion ratio (P < 0.05). Magnolol supplementation (200 and 300 mg/kg) could linearly increase albumen height and Haugh unit of fresh eggs in the late phase of the laying cycle (P < 0.01). And magnolol linearly alleviated the decline of the albumen height and Haugh unit of eggs stored for 14 d (P < 0.01). The total superoxide dismutase activity in the ovaries of M100 group was greater than that in the other treatments (P < 0.05). As dietary magnolol levels increased, villus height of jejunum and ileum linearly increased (P < 0.01). M200 and M300 groups had higher expression level of occludin in the ileum compared with group C (P < 0.01). The level of nitric oxide production and inducible nitric oxide synthase expression in the ileum of M200 group were lower than that in the C group (P < 0.05). In conclusion, dietary supplementation of 200 and 300 mg/kg magnolol can improve hen performance, albumen quality of fresh and storage eggs, and hepatic lipid metabolism in the late laying cycle. Also, magnolol has a good effect on increasing villi and improving the intestinal mucosal mechanical barrier function.


Assuntos
Antioxidantes/farmacologia , Compostos de Bifenilo/farmacologia , Galinhas/fisiologia , Ovos/normas , Intestinos/efeitos dos fármacos , Lignanas/farmacologia , Oviposição/efeitos dos fármacos , Ração Animal/análise , Animais , Antioxidantes/administração & dosagem , Compostos de Bifenilo/administração & dosagem , Galinhas/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Feminino , Intestinos/anatomia & histologia , Intestinos/fisiologia , Lignanas/administração & dosagem , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Óvulo
20.
Poult Sci ; 100(2): 643-653, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518118

RESUMO

Gender determination in incubated eggs (in ovo) has the potential to substitute the highly discussed practice of culling male layer chicks. The aim of this study was to investigate the effect pictures have on peoples' preferences toward in ovo sexing at different stages of embryonic development and chick culling. For this purpose, an online survey was conducted with a representative sample of 482 respondents in Germany. A within-subject design with 2 choice experiments was used to investigate the influence pictures have on respondents' preferences and willingness to pay. The first-choice experiment contained plain text only; the second contained also pictures of a chick or the incubated eggs at the corresponding stages of development. Findings reveal that in ovo gender determination at each proposed day of incubation (d1, d4, and d9) was preferred to chick culling. In ovo screening on d1 and d4 was significantly preferred to d9. This preference for early gender determination increased significantly as a consequence to the provision of pictures. Results furthermore reveal that a high error rate of gender determination or the lack of a meaningful utilization of incubated eggs can decrease approval for in ovo gender determination to an extent, where no positive willingness to pay remains. Findings of this study are useful for stakeholders in poultry production when considering the implementation of in ovo gender determination as a morally admissible substitute to chick culling.


Assuntos
Abate de Animais/métodos , Galinhas , Comportamento de Escolha , Comportamento do Consumidor , Animais , Feminino , Alemanha , Masculino , Modelos Econométricos , Óvulo , Fotografação , Fatores Socioeconômicos , Inquéritos e Questionários
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