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1.
Braz. j. biol ; 83: e250003, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339392

RESUMO

Abstract This study estimated the length-weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m taken for standard length (SL - 0.1 cm precision) and total weight (TW - 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.


Resumo Este estudo estimou as relações comprimento-peso de 16 espécies de peixes que ocorrem às margens de praias arenosas ao longo da bacia do baixo Rio Negro, Amazônia brasileira. As espécies foram capturadas durante um dia de cada mês, de outubro a novembro de 2016, no início da manhã e no início da noite, usando rede de cerco (20 m de comprimento e 3,5 m de altura, 5 malha mm entre nós opostos). As medidas foram feitas para comprimento padrão (SL - precisão de 0,1 cm) e peso total (TW - precisão de 0,01 g). Os parâmetros a e b da equação WT = a.LTb foram estimados. Os valores de a variaram de 0,0018 a 0,0226 e os valores de b variaram de 2,5271 a 3,3244. Este estudo também fornece novos dados sobre comprimentos máximos para seis espécies, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa e Trachydoras microstomus, e novos reportes dos parâmetros da LWRs de 15 espécies de peixes.


Assuntos
Animais , Perciformes , Caraciformes , Characidae , Brasil , Rios
2.
Braz. J. Biol. ; 83: 1-5, 2023. mapas, tab
Artigo em Inglês | VETINDEX | ID: vti-765542

RESUMO

This study estimated the length–weight relationships of 16 fish species occurring close to the shores of sandy beaches along the lower Negro River basin, Brazilian Amazon. The specimens were captured for one day each month, in October to November 2016, early in the morning and early evening, using trawl net (20 m length and 3.5 m height, 5 mm mesh between opposite knots). Measurements were taken for standard length (SL 0.1 cm precision) and total weight (TW 0.01 g precision). The parameters a and b of the equation WT = a.LTb were estimated. The a values ranged from 0.0018 to 0.0226 and b values ranged from 2.5271 to 3.3244. This study also provides new data on of maximum lengths for six species, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa and Trachydoras microstomus, and new reports of the LWRs parameters of 15 fish species.(AU)


Este estudo estimou as relações comprimento-peso de 16 espécies de peixes que ocorrem às margens de praias arenosas ao longo da bacia do baixo Rio Negro, Amazônia brasileira. As espécies foram capturadas durante um dia de cada mês, de outubro a novembro de 2016, no início da manhã e no início da noite, usando rede de cerco (20 m de comprimento e 3,5 m de altura, 5 malha mm entre nós opostos). As medidas foram feitas para comprimento padrão (SL - precisão de 0,1 cm) e peso total (TW - precisão de 0,01 g). Os parâmetros a e b da equação WT = a.LTb foram estimados. Os valores de a variaram de 0,0018 a 0,0226 e os valores de b variaram de 2,5271 a 3,3244. Este estudo também fornece novos dados sobre comprimentos máximos para seis espécies, Amazonsprattus scintilla, Brycon pesu, Moenkhausia megalops, Pachyurus paucirastrus, Reganella depressa e Trachydoras microstomus, e novos reportes dos parâmetros da LWRs de 15 espécies de peixes.(AU)


Assuntos
Animais , Peixes/anatomia & histologia , Peixes/crescimento & desenvolvimento
3.
PeerJ ; 6: e5675, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30397539

RESUMO

Considering the ecological importance and potential value of Hediste diversicolor, a better understanding of its metabolic rate and potential growth rates is required. The aims of this study are: (i) to describe key biometric relationships; (ii) to test the effects of temperature and body size on standard metabolic rate (as measure by oxygen consumption) to determine critical parameters, namely Arrhenius temperature (TA ), allometric coefficient (b) and reaction rate; and (iii) to determine the metabolic scope for activity (MSA) of H. diversicolor for further comparison with published specific growth rates. Individuals were collected in a Mediterranean lagoon (France). After 10 days of acclimatization, 7 days at a fixed temperature and 24 h of fasting, resting oxygen consumption rates (VO2 ) were individually measured in the dark at four different temperatures (11, 17, 22 and 27 °C) in worms weighing from 4 to 94 mgDW (n = 27 per temperature). Results showed that DW and L3 were the most accurate measurements of weight and length, respectively, among all the metrics tested. Conversion of WW (mg), DW (mg) and L3 (mm) were quantified with the following equations: DW = 0.15 × WW, L3 = 0.025 × TL(mm) + 1.44 and DW = 0.8 × L33.68. Using an equation based on temperature and allometric effects, the allometric coefficient (b) was estimated at 0.8 for DW and at 2.83 for L3. The reaction rate (VO2 ) equaled to 12.33 µmol gDW-1 h-1 and 0.05 µmol mm L3-1 h-1 at the reference temperature (20 °C, 293.15 K). Arrhenius temperature (TA ) was 5,707 and 5,664 K (for DW and L3, respectively). Metabolic scope for activity ranged from 120.1 to 627.6 J gDW-1 d-1. Predicted maximum growth rate increased with temperature, with expected values of 7-10% in the range of 15-20 °C. MSA was then used to evaluate specific growth rates (SGR) in several experiments. This paper may be used as a reference and could have interesting applications in the fields of aquaculture, ecology and biogeochemical processes.

4.
Semina ciênc. agrar ; 38(1): 391-400, jan.-fev. 2017. tab
Artigo em Inglês | VETINDEX | ID: vti-24726

RESUMO

This study aimed to evaluate the growth of body components in crossbred ewe lambs fed increasing levels of dietary concentrate and to determine the optimum level of supplementation for finishing ewe production. Thirty crossbred (½ Pantaneira × ½ Texel) wool ewe lambs fed Tifton 85 hay (Cynodon spp.) and different dietary concentrate levels (20, 40, 60, and 80% DM basis) were selected for study. At the beginning of the study, six animals were slaughtered for determination of initial body composition. The remaining animals were slaughtered at approximately 48 kg live weight. The growth of body components in relation to body growth was estimated from the allometric model BC = a × (FBW)b , where BC is body component weight, a and b are growth equation parameters, and FBW is fasted body weight. Carcass, muscle, bone, and gastrointestinal tract were late maturing (b<1, P<0.01 ). Carcass and carcass fat growth was positively affected (linear, P<0.05). Total fat weight increased with increasing concentrate level (P<0.05). The addition of up to 60% concentrate in growing ewe lamb diets is recommended for production of carcasses with early deposition of muscle and fat. The addition of 20% concentrate in ewe lab diets is sufficient for production of carcasses with maximum deposition of muscle and no excess fat.(AU)


Objetivou-se avaliar o crescimento dos componentes corporais de borregas mestiças alimentadas com níveis crescentes de concentrado na dieta e estabelecer o nível adequado de suplementação para produção de fêmeas para abate. Foram utilizadas 30 borregas lanadas, oriundas de cruzamentos com ovinos da raça Texel, alimentadas com feno de capim-Tifton 85 (Cynodon spp.) e quatro níveis de concentrado na dieta (20, 40, 60 e 80%). No início do experimento foi realizado abate para determinação da composição corporal de seis borregas. Os demais foram abatidos com aproximadamente 48 kg. Para o estudo do crescimento dos componentes em relação ao crescimento corporal dos animais foi utilizado o modelo CC = a x PCJb , onde CC = peso do componente corporal; a e b parâmetros das equações de crescimento e PCJ = peso corporal em jejum. A carcaça, músculos, ossos e trato gastrintestinal foram classificados como componentes de crescimento precoce (b<1; P<0,01). Foi observado efeito linear positivo dos níveis de concentrado sobre o crescimento da carcaça e gordura da carcaça (P<0,05). A quantidade total de gordura aumentou com os níveis crescentes de inclusão de concentrado na dieta (P<0,05). Recomenda-se a inclusão de 60% de concentrado na dieta de borregas em crescimento para produção de carcaças com precocidade para deposição de músculo e gordura. A inclusão de 20% de concentrado na dieta de borregas é o suficiente para produção de carcaças com máxima deposição de músculos e sem excesso de gordura.(AU)


Assuntos
Animais , Ovinos/metabolismo , Composição Corporal , Ração Animal
5.
Semina Ci. agr. ; 38(1): 391-400, 2017.
Artigo em Inglês | VETINDEX | ID: vti-744562

RESUMO

This study aimed to evaluate the growth of body components in crossbred ewe lambs fed increasing levels of dietary concentrate and to determine the optimum level of supplementation for finishing ewe production. Thirty crossbred (½ Pantaneira × ½ Texel) wool ewe lambs fed Tifton 85 hay (Cynodon spp.) and different dietary concentrate levels (20, 40, 60, and 80% DM basis) were selected for study. At the beginning of the study, six animals were slaughtered for determination of initial body composition. The remaining animals were slaughtered at approximately 48 kg live weight. The growth of body components in relation to body growth was estimated from the allometric model BC = a × (FBW)b, where BC is body component weight, a and b are growth equation parameters, and FBW is fasted body weight. Carcass, muscle, bone, and gastrointestinal tract were late maturing (b 1, P 0.01). Carcass and carcass fat growth was positively affected (linear, P 0.05) by concentrate level. Total fat weight increased with increasing concentrate level (P 0.05). The addition of up to 60% concentrate in growing ewe lamb diets is recommended for production of carcasses with early deposition of muscle and fat. The addition of 20% concentrate in ewe lab diets is sufficient for production of carcasses with maximum deposition of muscle and no excess fat.


Objetivou-se avaliar o crescimento dos componentes corporais de borregas mestiças alimentadas com níveis crescentes de concentrado na dieta e estabelecer o nível adequado de suplementação para produção de fêmeas para abate. Foram utilizadas 30 borregas lanadas, oriundas de cruzamentos com ovinos da raça Texel, alimentadas com feno de capim-Tifton 85 (Cynodon spp.) e quatro níveis de concentrado na dieta (20, 40, 60 e 80%). No início do experimento foi realizado abate para determinação da composição corporal de seis borregas. Os demais foram abatidos com aproximadamente 48 kg. Para o estudo do crescimento dos componentes em relação ao crescimento corporal dos animais foi utilizado o modelo CC = a x PCJb, onde CC = peso do componente corporal; a e b parâmetros das equações de crescimento e PCJ = peso corporal em jejum. A carcaça, músculos, ossos e trato gastrintestinal foram classificados como componentes de crescimento precoce (b 1; P 0,01). Foi observado efeito linear positivo dos níveis de concentrado sobre o crescimento da carcaça e gordura da carcaça (P 0,05). A quantidade total de gordura aumentou com os níveis crescentes de inclusão de concentrado na dieta (P 0,05). Recomenda-se a inclusão de 60% de concentrado na dieta de borregas em crescimento para produção de carcaças com precocidade para deposição de músculo e gordura. A inclusão de 20% de concentr

6.
J Fish Biol ; 89(1): 863-75, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27401485

RESUMO

A total of 66 fish species belonging to 32 families were recorded between November 2012 and April 2014 in the southern arm of the delta to the Atrato River. Total length (LT ; range: 1·7-48 cm), total mass (MT ), LT and MT relationships (b values ranged from 1·8 to 3·7, mostly with negative allometric growth), and LT frequency (for 25 species) were estimated for freshwater, estuarine and marine species. LT and MT of Porichthys pauciradiatus and Membras argentea are given for the first time and maximum LT records for 14 species exceed those in the literature.


Assuntos
Biodiversidade , Estuários , Peixes , Animais , Região do Caribe , Colômbia , Água Doce , Rios
7.
Animal ; 10(12): 2051-2060, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27225818

RESUMO

The mean fibre diameter (MFD) of wool is the primary determinant of price, processing performance and textile quality. This study determines the primary influences on MFD as Saxon Merino sheep age, by allometrically relating MFD to fleece-free liveweight (FFLwt). In total, 79 sheep were grazed in combinations of three stocking rates and two grazing systems (GS: sheep only; mixed with Angora goats) and studied over 3 years. Measurements were made over 14 consecutive periods (Segments), including segments of FFLwt gain or FFLwt loss. Using shearing and liveweight records and dye-bands on wool, the FFLwt and average daily gain (ADG) of each sheep were determined for each segment. The mean and range in key measurements were as follows: FFLwt, 40.1 (23.1 to 64.1) kg; MFD, 18.8 (12.7 to 25.8) µm. A random coefficient restricted maximum likelihood (REML) regression mixed model was developed to relate the logarithm of MFD to the logarithm of FFLwt and other effects. The model can be written in the form of ${\rm MFD}\,{\equals}\,\rkappa \left( {{\rm GS,}\,{\rm A}{\rm ,}\,{\rm Segment}{\rm .Plot,}\,{\rm Segment,}\,{\rm ADG}} \right){\times}{\rm FFLwt}^{{\left( {\ralpha \left( {{\rm GS}} \right){\plus}\rbeta \left(\rm A \right){\plus}\rgamma \left( {{\rm Segment}{\rm .Plot}} \right)} \right)}} $ , where $\ralpha \left( {{\rm GS}} \right)\,{\equals}\,\;\left\{ {\matrix{\!\! {0.32\left( {{\rm SE}\,{\equals}\,{\rm 0}{\rm .038}} \right)\,{\rm when}\,{\rm sheep}\,{\rm are}\,{\rm grazed}\,{\rm alone}} \hfill \cr \!\!\!\!{0.49\left( {{\rm SE}\,{\equals}\,{\rm 0}{\rm .049}} \right)\,{\rm when}\,{\rm sheep}\,{\rm are}\,{\rm mixed}\,{\rm with}\,{\rm goats}} \hfill \cr } } \right.$ ß(A) is a random animal effect, γ(Segment.Plot) a random effect associated with Segment.plot combinations, and κ a constant that depends on GS, random animal effects, random Segment.plot combination effects, Segment and ADG. Thus, MFD was allometrically related to the cube root of FFLwt over seasons and years for sheep, but to the square root of FFLwt for sheep grazed with goats. The result for sheep grazed alone accords with a primary response being that the allocation of nutrients towards the cross-sectional growth of wool follicles is proportional to the changes in the skin surface area arising from changes in the size of the sheep. The proportionality constant varied systematically with ADG, and in sheep only grazing, was about 5 when sheep lost 100 g/day and about 6 when sheep gained 100 g/day. The proportionality constant did not systematically change with chronological age. The variation in the allometric coefficient between individual sheep indicates that some sheep were more sensitive to changes in FFLwt than other sheep. Key practical implications include the following: (a) the reporting of systematic increases in MFD with age is likely to be a consequence of allowing sheep to increase in size during shearing intervals as they age; (b) comparisons of MFD between sheep are more likely to have a biological basis when standardised to a common FFLwt and not just to a common age;


Assuntos
Envelhecimento/fisiologia , Ovinos/fisiologia , Lã/fisiologia , Animais , Estudos Transversais , Folículo Piloso/fisiologia , Estações do Ano
8.
R. bras. Reprod. Anim. ; 37(3): 298-300, jul.-set. 2013. graf
Artigo em Português | VETINDEX | ID: vti-8116

RESUMO

Este estudo busca conhecer a variação dos índices corporais da viola como indicativo do período reprodutivo, a fim de que tal conhecimento possa auxiliar no processo de gestão e conservação desse importante recurso pesqueiro. Foi avaliado um total de 50 animais, sendo 25 machos e 25 fêmeas. Os dados mensurados foram: biometria, índice gonadossomático, índice hepatossomático e coeficiente de alometria. A viola não apresenta crescimento diferenciado entre machos e fêmeas no período que antecede a reprodução, entretanto a correlação entre o índice gonadossomático e o índice hepatossomático é um indicador da proximidade do período de desova.(AU)


Thus, the aim of this study is to know the variation of corporal indexes in Violas, as indicator of reproductive period, helping in the pregnancy process and conservation of this important fishing resource. It has been collected, a total of 50 animals, 25 males and 25 females. The data measured were: biometry, gonadosomatic and hepatossomatic indexes and allometric coefficient. The Viola does not present differential growth between males and females during the period before reproduction, however, the correlation between the gonadosomatic and hepatossomatic indexes is an indicator of the proximity of the spawn period. (AU)


Assuntos
Animais , Masculino , Feminino , Peixes/crescimento & desenvolvimento , Reprodução/fisiologia , Biometria/instrumentação , /métodos
9.
Vet. Méx ; 43(2): 113-121, abr.-jun. 2012. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-656403

RESUMO

The objective of the present study was to estímate growth curve parameters of length and weight in whitefish Chirostoma estor (EE), blacknose silverside Chirostoma promelas (PP) and their reciprocal hybrids (EP and PE) up to 300 days of age from a complete diallel cross under culture conditions in Morelia, Michoacan, Mexico. The length was measured monthly from hatching, while the weight was measured monthly from 120 days of age. The total number of each observation (samples) was analyzed for length 1006 (26), 771 (22), 513 (22) and 421 (21) for groups EP, PE, PP and EE, respectively. Total number of observations (samples) was analyzed for weight 630 (16), 521 (14), 263 (13) and 256 (13) for groups EP, PE, PP and EE, respectively. The growth curves for weight and length were estimated using nonlinear regression models. The group EE reached an estimated weight of 7.89 g at 300 days of age, 65% higher than the PP (4.78 g) and 57 % higher than the average of their hybrids (P < 0.01); EE had a length of 9.31 cm (14%) larger than PP (7.97 cm) and 13% larger than the average of their hybrids (P < 0.01). The four groups showed a positive allometric growth with values of 3.20 to 3.3 (P < 0.05). The results of this study are the first comparative estimates of growth characteristics up to 300 days of age for these species and their hybrids in captivity.


El objetivo del presente estudio fue estimar parámetros de las curvas de crecimiento del peso y la longitud en el pez blanco Chirostoma estor (EE), el pez blanco pico negro Chirostoma promelas (PP) y de sus híbridos recíprocos (EP y PE) hasta los 300 días de edad a partir de un cruzamiento dialélico completo bajo condiciones de cultivo en Morelia, Michoacán, México. La longitud se midió mensualmente desde la eclosión, mientras que el peso se midió mensualmente a partir de los 120 días. Los números totales de observaciones (muestras) analizadas para longitud fueron 1006 (26), 771 (22), 513 (22) y 421 (21) para los grupos EP, PE, PP y EE, respectivamente. Los números totales de observaciones (muestras) analizadas para peso fueron 630 (16), 521 (14), 263 (13) y 256 (13) para los grupos EP, PE, PP y EE, respectivamente. Las curvas de crecimiento para peso y longitud se estimaron con modelos de regresión no lineal. El grupo EE alcanzó un peso estimado de 7.89 g a los 300 días de edad, 65% mayor que el de PP (4.78 g) y 57% mayor que el promedio de los híbridos (P < 0.01); EE tuvo una longitud de 9.31 cm (14%) mayor que PP (7.97 cm) y 13% mayor que la del promedio de los híbridos (P < 0.01). Los cuatro grupos, mostraron un crecimiento de tipo alométrico positivo con valores de 3.2 a 3.3 (P < 0.05). Los resultados de este estudio son las primeras estimaciones comparativas de las características de crecimiento hasta los 300 días de edad para estas especies y sus híbridos en cautiverio.

10.
Artigo em Inglês | VETINDEX | ID: vti-717802

RESUMO

In order to evaluate the effects of broiler genotype and of heat exposure on performance, carcass characteristics, and protein and fat accretion, six hundred one-day-old male broilers were randomly assigned in a 2 x 3 factorial arrangement, according to the following factors: genetic group (selected and non-selected broilers) and pair-feeding scheme (Ad32 - reared under heat stress and fed ad libitum; Ad23 - reared at thermoneutrality and fed ad libitum; Pf23 - reared at thermoneutrality and pair fed with Ad32), with a total of six treatments with four replicates of 25 birds each. Independent of pair-feeding scheme, selected broilers showed better feed conversion, higher carcass yield, and lower abdominal fat deposition rate. However, as compared to non-selected broilers, they reduced more intensively feed intake when heat exposed, which promoted significant breast-yield decrease, and more pronounced changes on carcass chemical composition. These findings allows concluding that, in both genetic groups, both environmental temperature and feed-intake restriction influence abdominal fat deposition rate and other carcass characteristics; however, the impact of heat exposure on broiler performance is more noticeable on the selected line.

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