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1.
Pesqui. vet. bras ; 42: e07159, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1406216

RESUMO

In Brazil the second largest sheep herd is in Rio Grande do Sul and in recent years the demand for meat consumption of this specie has increased. Intensive farming systems have made considerable progress in this region with the objective of increasing the production of sheep for slaughter and obtaining a uniform batch to ensure better quality of sheep meat to consumers. However, the agglomeration and stress that animals go through can lead to the occurrence of illnesses and economic loss to producers. The objectives of this paper were to determine the main causes of death that affected sheep in a feedlot system, to establish forms of control and prophylaxis of diagnosed illnesses, and to estimate the economic losses resulting from them. The objective was also to determine the causes of condemnation of organs or carcasses in the slaughterhouses that processed the sheep were sent, and to estimate the losses in this productive sector. For this, a follow-up work was carried out in an establishment located in the city of São Lourenço do Sul, Rio Grande do Sul, from October 2020 to September 2021. The dead sheep at the feedlot were necropsied, and the diagnosis was made based on clinical signs, pathology, and bacteriology. The main diseases diagnosed were parasitic enteritis (15.4%), pneumonia (13%), and listeriosis (9.6%). In the slaughterhouse study, the lesions that led to the highest number of condemnations were hydatidosis (29.9%), renal congestion (26.2%), and renal ischemia (25.8%). The economic losses estimated for the death of sheep in 2021 was R$17,480.00, significantly lower than the approximate losses in 2019 and 2020 of R$50,000.00 and R$54,000.00, respectively. This highlights the importance of technical assistance to reduce these losses due to mortality in sheep raised in a feedlot system. It was also observed the kidneys of the sheep were the organs most frequently selected for condemnation. The economic value of the kidneys sold as disposed waste was eight time lower than that the value of kidneys suitable for consumption.


No Rio Grande do Sul está localizado o segundo maior rebanho de ovinos do Brasil e a demanda pelo consumo de carne desta espécie animal tem aumentado nos últimos anos. As criações em sistema intensivo têm tido um avanço considerável nesta região com o objetivo de aumentar a produção de ovinos para o abate e obter um lote uniforme, garantindo melhor qualidade da carne aos consumidores. Por outro lado, a aglomeração e o estresse que os animais passam pode levar a ocorrência de enfermidades e trazer prejuízos econômicos aos produtores. Os objetivos deste trabalho foram determinar as principais causas de morte que afetaram ovinos em um sistema intensivo de criação, estabelecer formas de controle e profilaxia das enfermidades diagnosticadas, bem como estimar as perdas econômicas delas decorrentes. Objetivou-se, também, determinar as causas de condenação de órgãos ou carcaças nos frigoríficos aos quais os ovinos eram enviados para o abate, para estimar as perdas neste setor produtivo. Para isso, foi realizado um trabalho de acompanhamento em um estabelecimento localizado no município de São Lourenço do Sul, Rio Grande do Sul, no período de outubro de 2020 até setembro de 2021. Os ovinos mortos eram necropsiados e o diagnóstico realizado com base nos sinais clínicos, patologia e bacteriologia. As principais enfermidades diagnosticadas foram as parasitoses (15,4%) e as pneumonias (13%), seguidas de listeriose (9,6%). As lesões que levaram ao maior número de condenações foram hidatidose (29,9%), congestão renal (26,2%) e isquemia renal (25,8%). A estimativa de perdas econômicas no ano de 2021 foi de R$17.480,00, enquanto as perdas por morte de ovinos nos anos 2019 e 2020 foram de aproximadamente R$50.000,00 e R$54.000,00, respectivamente. Ficou evidenciada a importância da assistência técnica para a redução dessas perdas por mortalidade de ovinos criados em sistema intensivo. Observou-se, ainda, que os rins foram os órgãos mais frequentemente descartados para o consumo e que o valor de descarte como resíduo era oito vezes menor do que o valor dos rins aptos para o consumo.


Assuntos
Animais , Doenças dos Ovinos/epidemiologia , Causas de Morte , Pneumonia , Brasil , Ovinos , Enterite/parasitologia , Listeriose
2.
Exp Appl Acarol ; 81(4): 599-607, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32676999

RESUMO

Babesia bovis and Babesia bigemina are tick-transmitted piroplasms that cause severe damage to the livestock industry in tropical regions of the world. Recent studies demonstrated differences in infection levels of these haemoparasites among bovine breeds and variation between individual cows regarding resistance to these diseases. This study aimed to estimate the repeatability and correlations between B. bovis and B. bigemina using two cattle breeding systems, an individual system (IS) and a collective paddock system (CPS). All animals were Holstein breed, and the levels of B. bovis and B. bigemina in blood samples were estimated by quantitative polymerase chain reaction (qPCR). The estimated correlations for the B. bigemina and B. bovis DNA copy number for IS and CPS were moderate and high, respectively, whereas repeatability estimates for both systems and both Babesia species were moderate. Although we cannot infer that the type of rearing system directly influenced the correlation and repeatability coefficients, it appears that the bovine parasitemia burden may be dependent on (or determine) the parasitemia burden on ticks because the bovines remained in the same place for a longer time in both systems. Thus, the babesiosis infection levels of the ticks may have been uniform, a phenomenon that also ensures greater uniformity in cattle infection. This factor may have favored the occurrence of infected ticks leading to higher repeatability estimates and correlations. Our study confirms high variability in resistance/susceptibility between breeds, and the high correlations found may be linked to this characteristic and the most intensive breeding type of dairy cattle. Besides, under the present study conditions, the estimated correlations suggest that measuring an infection level of one Babesia species can predict the level of infection of the other.


Assuntos
Babesia bovis , Babesia , Babesiose/epidemiologia , Doenças dos Bovinos , Bovinos/parasitologia , Animais , Babesia/isolamento & purificação , Babesia bovis/isolamento & purificação , Cruzamento , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , DNA de Protozoário/isolamento & purificação , Indústria de Laticínios , Parasitemia
3.
Plant Biol (Stuttg) ; 22(5): 872-880, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31984595

RESUMO

Enantiostyly is a floral polymorphism in which two floral forms in the same species differ in deflection of the stigma to right or left position. In monomorphic enantiostylous plants, flowers of the two morphs occur within the same individual, usually in the same proportion. In self-compatible species the function of monomorphic enantiostyly is proposed to increase outcrossing rates and offer a reproductive advantage under pollination limitation. Enantiostylous species are usually self-compatible and show heteranthery, with poricide anthers and pollen as pollinator reward; however, there are families, such as Vochysiaceae, that have different characteristics. We analysed the reproductive system and pollination biology of Qualea parviflora and Q. multiflora, two enantiostylous species from the Brazilian Cerrado that have specific morphological and physiological traits. For this, we characterized flower traits, performed hand pollinations and studied floral visitors. We found no differences between morphs in the proportion of flowers, nectar produced or its concentration, pollen quantity and fruit set. Both species were self-incompatible and quite generalist regarding floral visitors. Enantiostyly in self-incompatible plants seems to confer a reproductive advantage by reducing self-interference resulting from stigma clogging. This novel result helps to expand our knowledge on this complex floral polymorphism and opens new avenues for future research on this topic.


Assuntos
Myrtales , Polinização , Animais , Brasil , Flores/anatomia & histologia , Myrtales/fisiologia , Pólen , Polinização/fisiologia , Reprodução/fisiologia
4.
Insect Sci ; 27(6): 1322-1333, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31553524

RESUMO

Termite colonies are usually headed by primary reproductives, which establish nests during the swarming season. However, secondary reproductives may develop in some species and become supplementary or replacement breeders, extending colony lifespan. Here we investigate the developmental origin, fecundity and genetic characterization of ergatoid reproductives in the Neotropical termite Nasutitermes aquilinus (Holmgren), using morphometrical and histological techniques, five microsatellite loci and the COI mitochondrial DNA. Twelve measurements performed on 208 apterous individuals of N. aquilinus revealed 10 groups, including ergatoid females, which developed from major workers through two successive molts, and were characterized by the presence of imaginal features such as eyes and wing buds. The differentiation of these features was correlated to physogastric development in these ergatoids. Histology revealed oocytes in all maturation stages in worker-derived reproductives of N. aquilinus, presence of nonflagellate spermatozoa inside the spermatheca, and royal fat body. Thus, ergatoid reproductives were reproductively functional. According to the genotypes of 221 individuals from 11 nests, and mitochondrial haplotypes of 43 ergatoids, 73% of the colonies were simple families, whereas 27% were extended families. Despite the occurrence of related reproductives, low inbreeding rates were detected within and among colonies. Such values could be explained given that sib mating itself cannot result in a higher inbreeding rate but depend on several factors discussed in detail. This is the first study to investigate the genetic structure of termite colonies influenced by the development of ergatoids, and further investigations are encouraged to understand the influence of these reproductives on colony lifespan.


Assuntos
Isópteros/fisiologia , Animais , DNA Mitocondrial/análise , Feminino , Fertilidade/genética , Haplótipos , Isópteros/genética , Isópteros/crescimento & desenvolvimento , Masculino , Repetições de Microssatélites , Reprodução/genética
5.
Semina Ci. agr. ; 39(1): 311-316, jan.-fev. 2018. tab
Artigo em Inglês | VETINDEX | ID: vti-728480

RESUMO

The objective of the current study was to analyze the productive parameters of pigs housed in single and double capacity in the nursery, growth, and finishing phases in the Wean-to-Finish (WF) system. The research was carried out in the pig sector of the Centro de Ciências Agroveterinárias (CAV) at the Universidade do Estado de Santa Catarina (UDESC), in Lages, Santa Catarina. Ninety male castrated pigs weaned at 28 days of age and with an initial mean weight of 7.91 kg were used. They were housed in a WF shed and divided into two treatments: T1 with three animals per pen, 1.5 m2 of space per animal and 0.38 m of feeder space from weaning until slaughter; and T2 with six animals per pen, 0.75 m2 of space per animal and 0.19 m of feeder space in the nursery phase (up to 63 days old); and three animals per pen, with 1.5 m2 of space per animal and 0.38 m of feeder space for the growth and termination phases. The animals were individually weighed and the average daily feed intake (ADFI), average daily weight gain (ADWG), and feed conversion ratio (FCR) were calculated and a randomized design with a total of 10 replicate pens per treatment (with each pen considered an experimental unit) were used. Animals were slaughtered at 161 days of age. The design was completely randomized. We found no significant difference in ADWG, ADFI, or FCR in either the nursery or growth/finish phases an...(AU)


O objetivo do presente estudo foi analisar os parâmetros produtivos de suínos nas fases de creche, crescimento e terminação criados em sistema Wean-to-Finish (WF), alojados em lotações simples e dupla. A pesquisa foi realizado no setor de suinocultura do Centro de Ciências Agroveterinárias (CAV) da Universidade do Estado de Santa Catarina (UDESC), em Lages/SC. Foram utilizados 90 suínos machos, castrados, desmamados com 28 dias de idade com peso médio inicial de 7,91 kg. Estes, foram alojados em galpão WF e divididos em dois tratamentos: T1, com três animais por baia, espaço de 1,5 m2/animal e no comedouro de 0,38 m do alojamento até o abate; e T2, com seis animais por baia na fase de creche (até 63 dias de idade), espaço de 0,75 m2/animal, 0,19 m de espaço no comedouro; e para as fases crescimento e de terminação, três animais por baia, com espaço de 1,5 m2/animal e 0,38 m de espaço no comedouro. Foram realizadas pesagens individuais dos animais e calculados o consumo médio diário de ração (CMDR), o ganho médio de peso diário (GMPD) e a conversão alimentar (CA), e utilizado o delineamento ao acaso num total de dez baias de repetição por tratamento (cada baia foi considerada como uma unidade experimental). Os animais foram abatidos com idade de 161 dias. O delineamento foi inteiramente casualizado. Não houve diferença significativa nas fases referentes à creche e...(AU)


Assuntos
Animais , Criação de Animais Domésticos , Suínos/crescimento & desenvolvimento , Matadouros/organização & administração , Alojamento , Abate de Animais , Brasil
6.
Semina ciênc. agrar ; 39(1): 311-316, jan.-fev. 2018. tab
Artigo em Inglês | VETINDEX | ID: biblio-1501071

RESUMO

The objective of the current study was to analyze the productive parameters of pigs housed in single and double capacity in the nursery, growth, and finishing phases in the Wean-to-Finish (WF) system. The research was carried out in the pig sector of the Centro de Ciências Agroveterinárias (CAV) at the Universidade do Estado de Santa Catarina (UDESC), in Lages, Santa Catarina. Ninety male castrated pigs weaned at 28 days of age and with an initial mean weight of 7.91 kg were used. They were housed in a WF shed and divided into two treatments: T1 with three animals per pen, 1.5 m2 of space per animal and 0.38 m of feeder space from weaning until slaughter; and T2 with six animals per pen, 0.75 m2 of space per animal and 0.19 m of feeder space in the nursery phase (up to 63 days old); and three animals per pen, with 1.5 m2 of space per animal and 0.38 m of feeder space for the growth and termination phases. The animals were individually weighed and the average daily feed intake (ADFI), average daily weight gain (ADWG), and feed conversion ratio (FCR) were calculated and a randomized design with a total of 10 replicate pens per treatment (with each pen considered an experimental unit) were used. Animals were slaughtered at 161 days of age. The design was completely randomized. We found no significant difference in ADWG, ADFI, or FCR in either the nursery or growth/finish phases an...


O objetivo do presente estudo foi analisar os parâmetros produtivos de suínos nas fases de creche, crescimento e terminação criados em sistema Wean-to-Finish (WF), alojados em lotações simples e dupla. A pesquisa foi realizado no setor de suinocultura do Centro de Ciências Agroveterinárias (CAV) da Universidade do Estado de Santa Catarina (UDESC), em Lages/SC. Foram utilizados 90 suínos machos, castrados, desmamados com 28 dias de idade com peso médio inicial de 7,91 kg. Estes, foram alojados em galpão WF e divididos em dois tratamentos: T1, com três animais por baia, espaço de 1,5 m2/animal e no comedouro de 0,38 m do alojamento até o abate; e T2, com seis animais por baia na fase de creche (até 63 dias de idade), espaço de 0,75 m2/animal, 0,19 m de espaço no comedouro; e para as fases crescimento e de terminação, três animais por baia, com espaço de 1,5 m2/animal e 0,38 m de espaço no comedouro. Foram realizadas pesagens individuais dos animais e calculados o consumo médio diário de ração (CMDR), o ganho médio de peso diário (GMPD) e a conversão alimentar (CA), e utilizado o delineamento ao acaso num total de dez baias de repetição por tratamento (cada baia foi considerada como uma unidade experimental). Os animais foram abatidos com idade de 161 dias. O delineamento foi inteiramente casualizado. Não houve diferença significativa nas fases referentes à creche e...


Assuntos
Animais , Alojamento , Criação de Animais Domésticos , Matadouros/organização & administração , Suínos/crescimento & desenvolvimento , Abate de Animais , Brasil
7.
Plant Biol (Stuttg) ; 20(1): 101-112, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28977737

RESUMO

Three synchronopatric Cactaceae species, Echinopsis rhodotricha, Harrisia balansae and Praecereus saxicola, have mostly nocturnal anthesis and similar flowers, characteristics that motivated us to perform a comparative study of reproductive ecology. Reproductive phenology was sampled monthly from December 2014 to November 2015. We describe floral biology, breeding system via pollination treatments and evaluate floral visitors from focal and filming observations. Pollen grains found on moth proboscis were compared among cactus species under light microscopy. We used fluorescent dye particles to test intra- and interspecific pollen flow. These three species have extended flowering with greater intensity in the wet season, causing high overlap. They have white and hypocrateriformis flowers that open at twilight or nightfall and last about 15 h. H. balansae seems to be self-incompatible, while E. rhodotricha presented self-compatibility. P. saxicola presented self-fertility, but most of the population seems to be self-incompatible. We suggest sphingophily for the three species, but only P. saxicola was visited by Manduca rustica (Sphingidae). However, we observed pollen grains of all three species on the proboscis of moths, especially M. rustica and M. sexta. Prolonged anthesis allowed bees (herein considered as secondary pollinators) to visit flowers of E. rhodotricha and P. saxicola. It can be concluded that the studied species share nocturnal and diurnal pollinators, suggesting interspecific pollen flow, which, however, could not be detected with fluorescent dye particles. In view of the low frequency of primary pollinators, it appears that these three species have different reproductive strategies, ensuring the fruiting and production of viable seeds.


Assuntos
Cactaceae/fisiologia , Pólen/fisiologia , Polinização , Adaptação Fisiológica/fisiologia , Animais , Brasil , Ecologia , Flores/fisiologia , Mariposas/fisiologia , Polinização/fisiologia , Reprodução/fisiologia , Fatores de Tempo
8.
Plant Biol (Stuttg) ; 20(2): 244-251, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29069536

RESUMO

Since tropical trees often have long generation times and relatively small reproductive populations, breeding systems and genetic variation are important for population viability and have consequences for conservation. Miconia albicans is an obligate, diplosporous, apomictic species widespread in the Brazilian Cerrado, the savanna areas in central Brazil and elsewhere in the Neotropics. The genetic variability would be, theoretically, low within these male-sterile and possibly clonal populations, although some variation would be expected due to recombination during restitutional meiosis. We used ISSR markers to assess genetic diversity of M. albicans and to compare with other tropical trees, including invasive species of Melastomataceae. A total of 120 individuals from six populations were analysed using ten ISSR primers, which produced 153 fully reproducible fragments. The populations of M. albicans presented mean Shannon's information index (I) of 0.244 and expected heterozygosity (He ) of 0.168. Only two pairs of apparently clonal trees were identified, and genetic diversity was relatively high. A hierarchical amova for all ISSR datasets showed that 74% of the variance was found among populations, while only 26% of the variance was found within populations of this species. Multivariate and Bayesian analyses indicated marked separation between the studied populations. The genetic diversity generated by restitutional meiosis, polyploidy and possibly other genome changes may explain the morpho-physiological plasticity and the ability of these plants to differentiate and occupy such a wide territory and different environmental conditions. Producing enormous amounts of bird-dispersed fruits, M. albicans possess weedy potential that may rival other Melastomataceae alien invaders.


Assuntos
Melastomataceae/genética , Árvores/genética , Brasil , DNA de Plantas/genética , Marcadores Genéticos/genética , Variação Genética/genética , Repetições de Microssatélites/genética , Filogenia , Reação em Cadeia da Polimerase , Clima Tropical
9.
Rev. biol. trop ; Rev. biol. trop;65(2): 735-743, Apr.-Jun. 2017. tab, ilus
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-897577

RESUMO

AbstractPitcairnioideae is the second most diverse subfamily of bromeliads (Bromeliaceae), a group exclusive to tropical regions of the New World. Pitcairnioid bromeliads have floral traits assumed to promote outcrossing through biotic pollination systems; however, the reproductive biology of most of the species of this group has not been documented. Pitcairnia heterophylla is an epiphytic (seldom saxicolous) bromeliad occurring from Southern Mexico, into the Northern Andes. We studied the pollination and breeding system of P. heterophylla in an epiphytic population at a mountain forest in Costa Rica from January to April 2013. We performed hand pollination experiments (agamospermy, autonomous self-pollination, hand self-pollination and hand cross-pollination) on 89 flowers from 23 individuals (3-6 flowers per individual) in 2013 flowering season. Nectar production was measured on 18 unvisited flowers of six individuals with a hand-held refractometer. Simultaneously, floral visitors were recorded on eight individuals with trail cameras for a total of 918 hours (115 ± 52 hours per individual, mean ± SE). Under natural conditions, seed set (540.4 ± 55.2) was similar to manually selfed flowers (516.3 ± 41.5) and autonomously selfed flowers (521.1 ± 29.0), but lower to manually outcrossed flowers (670.2 ± 31.3). The flowers of P. heterophylla are self-compatible, capable of autonomous pollination, and non-agamospermous. Intrafloral self-pollination is facilitated by adichogamy and lack of floral herkogamy. The scentless red flowers of P. heterophylla with tubular corollas and nectar production suggested ornithophilic pollination which was confirmed by video recording of 46 hummingbird visits. The most common floral visitor was the short-billed hummingbird Lampornis calolaemus which accounted for 78 % of the visits. However, the visitation rate during the flowering season was low (0.6 visits per day per plant). Selfing in P. heterophylla might be explained as a mechanism of reproductive assurance and to reduce interspecific pollen flow with taxonomically unrelated plants.


ResumenLa subfamilia Pitcairnioideae es la segunda más diversa de las bromelias (Bromeliaceae), un grupo exclusivo de la región Neotropical. Las bromelias pitcairnioideas poseen rasgos florales que se asume promueven el exo-cruzamiento a través de sistemas de polinización biótica; sin embargo, la biología reproductiva de la mayoría de especies de este grupo no se ha documentado. Pitcairnia heterophylla es una bromelia epífita (raramente saxícola) que se encuentra en el sur de México, América Central y el norte de los Andes. Se estudió la polinización y el sistema de apareamiento de una población P. heterophylla en un bosque montano en Costa Rica entre enero y abril 2013. Se realizaron cuatro experimentos de polinización (agamospermia, auto-polinización espontánea, auto-polinización manual, exo-polinización manual) en 89 flores de 23 individuos (3-6 flores por individuo). Se cuantificó la producción de néctar de 18 flores en seis individuos con un refractómetro. Simultáneamente, se registraron los visitantes florales de ocho individuos en el campo con ayuda de cámaras trampa por un total de 918 horas (115 ± 52 horas por individuo, promedio ± ES). Bajo condiciones naturales la producción de semillas fue similar (540.4 ± 55.2) a la producción de las flores auto-polinizadas manualmente (516.3 ± 41.5) y las flores auto-polinizadas espontáneamente (521.1 ± 29.0), pero fue menor a las flores exo-cruzadas (670.2 ± 31.3). Las flores de P. heterophylla son auto-compatibles, con alta capacidad de polinización espontánea y sin capacidad de agamospermia. La auto-polinización intra-floral es facilitada por la ausencia de dicogamia y hercogamia floral. Las flores rojas, sin aroma, con corola tubular y con producción de néctar sugirieron polinización por ornitofilia, lo que se confirmó con el registro de 46 visitas por colibríes (Apodiformes: Trochilidae). El visitante floral más común fue Lampornis calolaemus (78 % de las visitas). A pesar de esto, la tasa de visitas durante el periodo de estudio fue baja (0.6 visitas por día por planta). La capacidad de autofecundación de P. heterophylla puede ser explicada como un mecanismo de aseguramiento reproductivo, así como para reducir el flujo de polen inter-específico de plantas taxonómicamente no relacionadas.

10.
Plant Reprod ; 30(2): 69-79, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28303339

RESUMO

Late-acting self-incompatibility (LSI) has been defined as a genetically controlled self-sterility mechanism that prevents seed set by selfing, despite normal pollen tube growth and ovule penetration in self-pollinated pistils. In species of the Bignoniaceae with LSI, such as Handroanthus impetiginosus, the selfed pistils are characterized by a marked delay in ovule penetration, fertilization, and endosperm initiation, followed by uniform pistil abscission. This highlights the contentious possibility of a post-zygotic self-incompatibility system. However, previous studies were unable to confirm fusion of the sperm and egg cell nuclei in selfed ovules. In the present study, the cytology of the embryo sac, double fertilization, and pistil longevity was investigated in H. impetiginosus using comparative nuclei microspectrofluorometry of DAPI-stained sections of self- vs. unpollinated pistils. Differences in both pistil longevity and ovary size between self- and unpollinated flowers at the time of pistil abscission were significant. Zygotes with double the DNA content in their nuclei relative to unfertilized egg cell nuclei were verified in selfed ovules from the first day after pollination onward, and G1 karyogamy appeared to have occurred. Our cytological analysis clearly indicates that ovules of self-pollinated pistils in H. impetiginosus are fertilized before pistil abscission but no embryogenesis initiation occurs, which strongly supports the idea of a post-zygotic self-incompatibility mechanism.


Assuntos
Bignoniaceae/fisiologia , Autoincompatibilidade em Angiospermas , Bignoniaceae/genética , DNA de Plantas , Flores/fisiologia , Microespectrofotometria , Polinização , Autoincompatibilidade em Angiospermas/genética
11.
Am Nat ; 189(3): 297-314, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28221824

RESUMO

Dioecy has a demographic disadvantage compared with hermaphroditism: only about half of reproductive adults produce seeds. Dioecious species must therefore have fitness advantages to compensate for this cost through increased survival, growth, and/or reproduction. We used a full life cycle approach to quantify the demographic costs and benefits associated with dioecy while controlling for demographic differences between dioecious and hermaphroditic species related to other functional traits. The advantage of this novel approach is that we can focus on the effect of breeding system across a diverse tree community. We built a composite integral projection model for hermaphroditic and dioecious tree populations from Barro Colorado Island, Panama, using long-term demographic and newly collected reproductive data. Integration of all costs and benefits showed that compensation was realized through increased seed production, resulting in no net costs of dioecy. Compensation was also facilitated by the low contribution of reproduction to population growth. Estimated positive effects of dioecy on tree growth and survival were small and insignificant for population growth rates. Our model revealed that, for long-lived organisms, the cost of having males is smaller than generally expected. Hence, little compensation is required for dioecious species to maintain population growth rates similar to those of hermaphroditic species.


Assuntos
Reprodução , Árvores/crescimento & desenvolvimento , Colorado , Panamá , Clima Tropical
12.
Braz. j. biol ; Braz. j. biol;76(4): 975-982, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828090

RESUMO

Abstract Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine ‘Isabel’ (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) and August 2012 (P4). We recorded the duration (days) of the phenological stages, pruning (P), woolly bud (W), budburst (B), inflorescence development (ID), flowering (F), ripening (R) and harvest (H). We analysed the floral biology, the sexual system and the breeding system. We measured the growing degree days (GDD) required to reach the subperiods P-B, B-F and F-H. The periods P1, P2, P3 and P4 lasted for 116, 125, 117 and 130 days, respectively. The number of days of harvest were similar in the same dry (P1 and P3) and rainy (P2 and P4) periods. All the periods that we recorded were shorter than those observed in other regions of Brazil, which may be attributable to the mean temperature and carbohydrate metabolism. The flowers are green, hermaphroditic, with an odour of mignonette, low pollen viability and autogamous. The base temperature of 10°C was considered the most adequate for the subperiods as has been documented for other grape varieties in Brazil. Thus, temperature was also the most adequate for the cycles, presenting a smaller standard deviation (0.119, 0.147, 0.156 and 0.153 to P1, P2, P3 and P4, respectively) when compared to a base temperature of 12°C (0.122, 0.158, 0.165 and 0.160 to P1, P2, P3 and P4, respectively). The higher and the lower observed GDD were 1972.17 and 1870.05, respectively, both above the values recorded in other parts of Brazil for same variety. The phonological results, including knowledge of growing degree days, are important to the planning of cultures at the study site and in other regions that have similar climatic conditions and make it possible to pre-determine the harvest.


Resumo Fenologia e biologia reprodutiva de espécies cultivadas são importantes para a compreensão dos requerimentos para a produção de frutos e sementes, bem como para o manejo de polinizadores. O presente estudo objetivou caracterizar a fenologia, a biologia reprodutiva e a exigência térmica (graus-dias) da videira “Isabel” (Vitis labrusca) no nordeste do Brasil, durante janeiro/2011 (P1), Agosto/2011 (P2), Abril/2012 (P3) e Agosto/2012 (P4). Analisamos a duração (dias) dos estádios fenológicos poda (PO), gema-algodão (GA), brotamento (BR), aparecimento da inflorescência (AI), florescimento (FL), início da maturação (IM) e colheita (CO). Analisamos a biologia floral, o sistema sexual e o sistema reprodutivo. As exigências térmicas foram obtidas em termos de graus-dia (GD) necessários para atingir os subperíodos PO-BR, BR-FL e FL-CO. A duração do ciclo foi de 116, 125, 117 e 130 dias para as épocas P1, P2, P3 e P4 respectivamente, sendo o número de dias de colheita semelhantes no período seco (P1 e P3) e chuvoso (P2 e P4). Todos os períodos analisados foram mais curtos do que aqueles observados em outras regiões do Brasil, o que pode ser atribuído à temperatura média e ao metabolismo de carboidratos. As flores são verdes, hermafroditas, com odor almiscarado, baixa viabilidade polínica e autógama. A temperatura base de 10ºC foi considerada a mais adequada para os subperíodos e tem sido documentada para outras variedades de uva no Brasil; portanto, a temperatura foi também a mais adequada para os ciclos, apresentando um desvio padrão menor (0,119; 0,147; 0,156 e 0,153 para P1, P2, P3 e P4, respectivamente), comparado com uma temperatura base de 12ºC (0,122; 0,158; 0,165 e 0,160 para P1, P2, P3 e P4, respectivamente). O maior é o menor GDD observado foram 1972,17 e 1870,05, respectivamente. Os resultados fenológicos, incluindo o conhecimento dos graus dias, são importantes para o planejamento de culturas no local e em outras regiões com condições climáticas semelhantes, tornando possível pré-determinar a colheita.


Assuntos
Vitis/crescimento & desenvolvimento , Reprodução , Sementes/crescimento & desenvolvimento , Temperatura , Brasil , Flores/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento
13.
Braz. J. Biol. ; 76(4): 975-982, Oct.-Dec. 2016. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-21645

RESUMO

Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine Isabel (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) and August 2012 (P4). We recorded the duration (days) of the phenological stages, pruning (P), woolly bud (W), budburst (B), inflorescence development (ID), flowering (F), ripening (R) and harvest (H). We analysed the floral biology, the sexual system and the breeding system. We measured the growing degree days (GDD) required to reach the subperiods P-B, B-F and F-H. The periods P1, P2, P3 and P4 lasted for 116, 125, 117 and 130 days, respectively. The number of days of harvest were similar in the same dry (P1 and P3) and rainy (P2 and P4) periods. All the periods that we recorded were shorter than those observed in other regions of Brazil, which may be attributable to the mean temperature and carbohydrate metabolism. The flowers are green, hermaphroditic, with an odour of mignonette, low pollen viability and autogamous. The base temperature of 10°C was considered the most adequate for the subperiods as has been documented for other grape varieties in Brazil. Thus, temperature was also the most adequate for the cycles, presenting a smaller standard deviation (0.119, 0.147, 0.156 and 0.153 to P1, P2, P3 and P4, respectively) when compared to a base temperature of 12°C (0.122, 0.158, 0.165 and 0.160 to P1, P2, P3 and P4, respectively). The higher and the lower observed GDD were 1972.17 and 1870.05, respectively, both above the values recorded in other parts of Brazil for same variety.(AU)


Fenologia e biologia reprodutiva de espécies cultivadas são importantes para a compreensão dos requerimentos para a produção de frutos e sementes, bem como para o manejo de polinizadores. O presente estudo objetivou caracterizar a fenologia, a biologia reprodutiva e a exigência térmica (graus-dias) da videira Isabel (Vitis labrusca) no nordeste do Brasil, durante janeiro/2011 (P1), Agosto/2011 (P2), Abril/2012 (P3) e Agosto/2012 (P4). Analisamos a duração (dias) dos estádios fenológicos poda (PO), gema-algodão (GA), brotamento (BR), aparecimento da inflorescência (AI), florescimento (FL), início da maturação (IM) e colheita (CO). Analisamos a biologia floral, o sistema sexual e o sistema reprodutivo. As exigências térmicas foram obtidas em termos de graus-dia (GD) necessários para atingir os subperíodos PO-BR, BR-FL e FL-CO. A duração do ciclo foi de 116, 125, 117 e 130 dias para as épocas P1, P2, P3 e P4 respectivamente, sendo o número de dias de colheita semelhantes no período seco (P1 e P3) e chuvoso (P2 e P4). Todos os períodos analisados foram mais curtos do que aqueles observados em outras regiões do Brasil, o que pode ser atribuído à temperatura média e ao metabolismo de carboidratos. As flores são verdes, hermafroditas, com odor almiscarado, baixa viabilidade polínica e autógama. A temperatura base de 10ºC foi considerada a mais adequada para os subperíodos e tem sido documentada para outras variedades de uva no Brasil; portanto, a temperatura foi também a mais adequada para os ciclos, apresentando um desvio padrão menor (0,119; 0,147; 0,156 e 0,153 para P1, P2, P3 e P4, respectivamente), comparado com uma temperatura base de 12ºC (0,122; 0,158; 0,165 e 0,160 para P1, P2, P3 e P4, respectivamente). O maior é o menor GDD observado foram 1972,17 e 1870,05, respectivamente.(AU)


Assuntos
Vitis/crescimento & desenvolvimento , Produtos Agrícolas , Estágios do Ciclo de Vida
14.
R. bras. Ci. avíc. ; 18(4): 619-628, Out-Dez. 2016. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-683981

RESUMO

The objective of this study was to identify the growth curve of live weight of turkeys reared in different systems (intensive and free- range) with the best mathematical model. To achieve this goal, the live weight of male and female turkeys (Large White) reared for 0-18 weeks were used. Logistic, Gompertz, Von Bertalanffy, and Gauss were used to determine the best model for the turkeys. In comparison of the models, values of Coefficient of Determination (R2), Mean Squares of Error (MSE) and Model Efficiency (ME) were used. In Von Bertalanffy model, the coefficient of determinations for males and females were found as 0.9974 and 0.99915 in intensive system and 0.9794 and 0.9804 in Free-Range system, respectively. As a result of this study, because the highest R2 and the lowest MSE were observed in Von Bertalanffy model, it was the best among the models to identify growth curve of the turkeys.(AU)


Assuntos
Animais , Masculino , Feminino , Perus/crescimento & desenvolvimento , Perus/fisiologia , Reprodução/fisiologia , Dinâmica não Linear , Aves Domésticas/crescimento & desenvolvimento , Interpretação Estatística de Dados , Métodos de Análise Laboratorial e de Campo/métodos , Peso Corporal/fisiologia , Criação de Animais Domésticos/métodos , /veterinária
15.
Rev. bras. ciênc. avic ; 18(4): 619-628, Out-Dez. 2016. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1490310

RESUMO

The objective of this study was to identify the growth curve of live weight of turkeys reared in different systems (intensive and free- range) with the best mathematical model. To achieve this goal, the live weight of male and female turkeys (Large White) reared for 0-18 weeks were used. Logistic, Gompertz, Von Bertalanffy, and Gauss were used to determine the best model for the turkeys. In comparison of the models, values of Coefficient of Determination (R2), Mean Squares of Error (MSE) and Model Efficiency (ME) were used. In Von Bertalanffy model, the coefficient of determinations for males and females were found as 0.9974 and 0.99915 in intensive system and 0.9794 and 0.9804 in Free-Range system, respectively. As a result of this study, because the highest R2 and the lowest MSE were observed in Von Bertalanffy model, it was the best among the models to identify growth curve of the turkeys.


Assuntos
Masculino , Feminino , Animais , Aves Domésticas/crescimento & desenvolvimento , Dinâmica não Linear , Interpretação Estatística de Dados , Métodos de Análise Laboratorial e de Campo/métodos , Perus/crescimento & desenvolvimento , Perus/fisiologia , Reprodução/fisiologia , Criação de Animais Domésticos/métodos , Peso Corporal/fisiologia
16.
Plant Biol (Stuttg) ; 18(6): 903-912, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27634630

RESUMO

This study tested the hypothesis that self-compatibility would be associated with floral traits that facilitate autonomous self-pollination to ensure reproduction under low pollinator visitation. In a comparison of two pairs of Ipomoea species with contrasting breeding systems, we predicted that self-compatible (SC) species would have smaller, less variable flowers, reduced herkogamy, lower pollinator visitation and higher reproductive success than their self-incompatible (SI) congeners. We studied sympatric species pairs, I. hederacea (SC)- I. mitchellae (SI) and I. purpurea (SC)-I. indica (SI), in Mexico, over two years. We quantified variation in floral traits and nectar production, documented pollinator visitation, and determined natural fruit and seed set. Hand-pollination and bagging experiments were conducted to determine potential for autonomous self-pollination and apomixis. Self-compatible Ipomoea species had smaller flowers and lower nectar production than SI species; however, floral variation and integration did not vary according to breeding system. Bees were primary pollinators of all species, but visitation rates were seven times lower in SC than SI species. SC species had a high capacity for autonomous self-pollination due to reduced herkogamy at the highest anther levels. Self-compatible species had two to six times higher fruit set than SI species. Results generally support the hypothesis that self-compatibility and autonomous self-pollination ensure reproduction under low pollinator visitation. However, high variation in morphological traits of SC Ipomoea species suggests they maintain variation through outcrossing. Furthermore, reduced herkogamy was associated with high potential for autonomous self-pollination, providing a reproductive advantage that possibly underlies transitions to self-compatibility in Ipomoea.


Assuntos
Flores , Ipomoea , Cruzamento , Flores/anatomia & histologia , Flores/fisiologia , Frutas/anatomia & histologia , Frutas/fisiologia , Ipomoea/anatomia & histologia , Ipomoea/fisiologia , México , Fenótipo , Polinização , Reprodução , Sementes/anatomia & histologia , Sementes/fisiologia , Autofertilização , Simpatria
17.
Ann Bot ; 118(2): 281-303, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27373539

RESUMO

BACKGROUND AND AIMS: Poa subgenus Poa supersect. Homalopoa has diversified extensively in the Americas. Over half of the species in the supersection are diclinous; most of these are from the New World, while a few are from South-East Asia. Diclinism in Homalopoa can be divided into three main types: gynomonoecism, gynodioecism and dioecism. Here the sampling of species of New World Homalopoa is expanded to date its origin and diversification in North and South America and examine the evolution and origin of the breeding system diversity. METHODS: A total of 124 specimens were included in the matrix, of which 89 are species of Poa supersect. Homalopoa sections Acutifoliae, Anthochloa, Brizoides, Dasypoa, Dioicopoa, Dissanthelium, Homalopoa sensu lato (s.l.), Madropoa and Tovarochloa, and the informal Punapoa group. Bayesian and parsimony analyses were conducted on the data sets based on four markers: the nuclear ribosomal internal tanscribed spacer (ITS) and external transcribed spacer (ETS), and plastid trnT-L and trnL-F. Dating analyses were performed on a reduced Poa matrix and enlarged Poaceae outgroup to utilize fossils as calibration points. A relaxed Bayesian molecular clock method was used. KEY RESULTS: Hermaphroditism appears to be pleisiomorphic in the monophyletic Poa supersect. Homalopoa, which is suggested to have originated in Eurasia 8·4-4·2 million years ago (Mya). The ancestor of Poa supersect. Homalopoa radiated throughout the New World in the Late Miocene-Early Pliocene, with major lineages originating during the Pliocene to Pleistocene (5-2 Mya). Breeding systems are linked to geographic areas, showing an evolutionary pattern associated with different habitats. At least three major pathways from hermaphroditism to diclinism are inferred in New World Homalopoa: two leading to dioecism, one via gynodioecism in South America and another directly from hermaphroditism in North America, a result that needs to be checked with a broader sampling of diclinous species in North America. A third pathway leads from hermaphroditism to gynomonoecism in Andean species of South America, with strictly pistillate species evolving in the highest altitudes. CONCLUSIONS: Divergence dating provides a temporal context to the evolution of breeding systems in New World Poa supersect. Homalopoa The results are consistent with the infrageneric classification in part; monophyletic sections are confirmed, it is proposed to reclassify species of sect. Acutifoliae, Dasypoa and Homalopoa s.l. and it is acknowledged that revision of the infrageneric taxonomy of the gynomonoecious species is needed.


Assuntos
Melhoramento Vegetal , Poa/genética , Poaceae/genética , Teorema de Bayes , Evolução Biológica , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Flores/classificação , Flores/genética , Fósseis , América do Norte , Filogenia , Plastídeos/genética , Poa/classificação , Poaceae/classificação , Análise de Sequência de DNA , América do Sul
18.
Am J Bot ; 102(5): 745-57, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26022488

RESUMO

PREMISE OF THE STUDY: Isometric and allometric scaling of a conserved floral plan could provide a parsimonious mechanism for rapid and reversible transitions between breeding systems. This scaling may occur during transitions between predominant autogamy and xenogamy, contributing to the maintenance of a stable mixed mating system. METHODS: We compared nine disjunct populations of the polytypic, mixed mating species Oenothera flava (Onagraceae) to two parapatric relatives, the obligately xenogamous species O. acutissima and the mixed mating species O. triloba. We compared floral morphology of all taxa using principal component analysis (PCA) and developmental trajectories of floral organs using ANCOVA homogeneity of slopes. KEY RESULTS: The PCA revealed both isometric and allometric scaling of a conserved floral plan. Three principal components (PCs) explained 92.5% of the variation in the three species. PC1 predominantly loaded on measures of floral size and accounts for 36% of the variation. PC2 accounted for 35% of the variation, predominantly in traits that influence pollinator handling. PC3 accounted for 22% of the variation, primarily in anther-stigma distance (herkogamy). During O. flava subsp. taraxacoides development, style elongation was accelerated relative to anthers, resulting in positive herkogamy. During O. flava subsp. flava development, style elongation was decelerated, resulting in zero or negative herkogamy. Of the two populations with intermediate morphology, style elongation was accelerated in one population and decelerated in the other. CONCLUSIONS: Isometric and allometric scaling of floral organs in North American Oenothera section Lavauxia drive variation in breeding system. Multiple developmental paths to intermediate phenotypes support the likelihood of multiple mating system transitions.


Assuntos
Flores/anatomia & histologia , Oenothera/anatomia & histologia , Oenothera/fisiologia , Evolução Biológica , Flores/genética , Flores/fisiologia , Geografia , México , Oenothera/genética , Fenótipo , Reprodução , Estados Unidos
19.
Am J Bot ; 102(5): 758-64, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26022489

RESUMO

PREMISE OF THE STUDY: The mating system is an important component of the complex set of reproductive isolation barriers causing plant speciation. However, empirical evidence showing that the mating system may promote reproductive isolation in co-occurring species is limited. The mechanisms by which the mating system can act as a reproductive isolation barrier are also largely unknown. METHODS: Here we studied progeny arrays genotyped with microsatellites and patterns of stigma-anther separation (herkogamy) to understand the role of mating system shifts in promoting reproductive isolation between two hybridizing taxa with porous genomes, Pitcairnia albiflos and P. staminea (Bromeliaceae). KEY RESULTS: In P. staminea, we detected increased selfing and reduced herkogamy in one sympatric relative to two allopatric populations, consistent with mating system shifts in sympatry acting to maintain the species integrity of P. staminea when in contact with P. albiflos. CONCLUSIONS: Mating system variation is a result of several factors acting simultaneously in these populations. We report mating system shifts as one possible reproductive barrier between these species, acting in addition to numerous other prezygotic (i.e., flower phenology and pollination syndromes) and postzygotic barriers (Bateson-Dobzhansky-Muller genetic incompatibilities).


Assuntos
Bromeliaceae/anatomia & histologia , Bromeliaceae/fisiologia , Repetições de Microssatélites , Isolamento Reprodutivo , Brasil , Bromeliaceae/genética , Flores/anatomia & histologia , Especiação Genética , Genótipo , Reprodução , Simpatria
20.
Plant Biol (Stuttg) ; 16(5): 956-66, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24641568

RESUMO

The mistletoe Psittacanthus robustus was studied as a model to link flower phenology and nectar secretion strategy to pollinator behaviour and the reproductive consequences for the plant. The bright-coloured flowers presented diurnal anthesis, opened asynchronously throughout the rainy season and produced copious dilute nectar as the main reward for pollinators. Most nectar was secreted just after flower opening, with little sugar replenishment after experimental removals. During the second day of anthesis in bagged flowers, the flowers quickly reabsorbed the offered nectar. Low values of nectar standing crop recorded in open flowers can be linked with high visitation rates by bird pollinators. Eight hummingbirds and two passerines were observed as potential pollinators. The most frequent flower visitors were the hummingbirds Eupetomena macroura and Colibri serrirostris, which actively defended flowering mistletoes. The spatial separation between anthers, stigma and nectar chamber promotes pollen deposition on flapping wings of hovering hummingbirds that usually probe many flowers per visit. Seed set did not differ between hand-, self- and cross-pollinated flowers, but these treatments set significantly more seeds than flowers naturally exposed to flower visitors. We suggest that the limitation observed in the reproductive success of this plant is not related to pollinator scarcity, but probably to the extreme frequency of visitation by territorial hummingbirds. We conclude that the costs and benefits of plant reproduction depend on the interaction strength between flowers and pollinators, and the assessment of nectar secretion dynamics, pollinator behaviour and plant breeding system allows clarification of the complexity of such associations.


Assuntos
Aves/fisiologia , Loranthaceae/fisiologia , Néctar de Plantas/metabolismo , Polinização , Animais , Comportamento Animal , Flores/fisiologia , Reprodução , Territorialidade
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