With the aim of evaluating how changes in the metabolic status in the last month of pregnancy affects reproductive efficiency, forty six Bos indicus multiparous cows (5.5 ± 2.4 parturitions), were used. Measureme...With the aim of evaluating how changes in the metabolic status in the last month of pregnancy affects reproductive efficiency, forty six Bos indicus multiparous cows (5.5 ± 2.4 parturitions), were used. Measurements of body weight (BW), body condition score (BCS) and dorsal back fat (BF) were taken in the last month of pregnancy, postpartum period previous to synchronization (average 50 d) and at breeding by natural mating following synchronization with a progestin (average 70 d). Average postpartum days to resumption to ovarian activity were 79.96 ± 16.5 d, and average postpartum days to conception was 88.5 ± 14 d. Days postpartum to resumption of the ovarian activity was positively correlated (0.51, P 0.01) with days postpartum to conception, also, days postpartum to conception was positively correlated with prepartum back fat (14 d before parturition) (0.44, P 0.05). It was observed that BF at calving which is an objective measurement had a low correlation with other productive variables such as BCS and BW (always less than 0.39). Body fat might be a more reliable indicator of the current metabolic status of the animal particularly in the last month of pregnancy when the indicators of BCS are somehow more difficult to interpret and subjective.展开更多
Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the ...Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the life cycle of individuals because it is associated with new demands： After leaving the nest, individuals have to find their own food and cope with a new set of previously unknown stressors. In this study, we aimed at better understanding how energetically demanding the post-ftedging period is in house sparrows Passer domesticus by measuring several indices of a fledgling＇s state （body condition, fat and muscle scores and plumage quality）. If the energetic demands of the post-fledging period are greater than those of the adult life, we predicted that fledglings should be in lower condition and should have a plumage of lower quality relative to adults. Supporting this prediction, the condition and the plumage of fledglings differed dramatically from those of adults. Interestingly, this difference disappeared in autumn. Overall, our results suggest that the post-fledging period is probably one of the most energetically demanding of the life cycle in this species. Supporting this idea, the resighting probability of fledglings was lower relative to adults. However, resighting probability depends on many factors （mortality, dispersal, habitat use and behaviours） and future studies are necessary to tease apart their relative importance in determining resighting probability [Current Zoology 60 （4）： 449-459, 2014].展开更多
Despite the widely accepted view that planted forests are valuable habitat for wildlife species,there is a lack of empirical evidence showing the suitability of this novel habitat,especially in relation to plantations...Despite the widely accepted view that planted forests are valuable habitat for wildlife species,there is a lack of empirical evidence showing the suitability of this novel habitat,especially in relation to plantations of exotic tree species.Furthermore,little is known about the effects of forest management on the ecology and dynamics of wild populations in the Neotropics.During the breeding season,the migrant flycatcher White-crested Elaenia is the most abundant bird species in forested landscapes in Chile.For several years we have studied different aspects of these artificial forests in the coastal range of south-central Chile as habitat for the species,particularly in contrast to the native forest.In general,our results indicate that plantation forests offer a poorer quality habitat,where the density of the species tends to be lower than in the native forest,although a significant edge effect suggests that its quality can be mitigated by planting as a matrix mosaic with native forest.Furthermore,compared to native forests,populations in plantations contained a higher proportion of younger adult individuals maintaining larger territories,and showing poorer body condition.We suggest that these differences could also have an impact on the birds'longevity and survival.展开更多
The objective was to quantify relationships between sow body condition and subsequent reproduction. Multiparous sows were measured at breeding (n = 1571) and farrowing (n = 887) on a commercial farm in eastern North C...The objective was to quantify relationships between sow body condition and subsequent reproduction. Multiparous sows were measured at breeding (n = 1571) and farrowing (n = 887) on a commercial farm in eastern North Carolina. Sow body condition measures included: sow body condition caliper (CS), weight (BW), backfat, longissimus muscle area (LMA) and visual body condition score (BCS). Sow production traits were: number born alive (NBA), litter birth weight (LBW), number weaned (NW), piglet survival (PS), litter weaning weight (LWW), wean-to-conception interval (WCI), farrowing rate and lactation average daily feed intake. Data were analyzed in SAS using PROC GLM for continuous traits and PROC GLIMMIX for categorical traits. Breeding CS had a curvilinear relationship (P 0.05) with NBA, LBW, NW, PS and WCI, with a CS of 15 being optimal for NBA, NW and PS and 14 ideal for LBW and WCI. Breeding LMA had a curvilinear relationship (P 0.05) with PS, with 51.5 cm<sup>2</sup> maximizing survival. Breeding BCS had a curvilinear relationship (P 0.05) with NBA, LBW, NW, PS and WCI, with 3.2 being optimal for NBA, NW and WCI and 3.0 ideal for LBW and PS. Farrowing CS had a curvilinear relationship (P 0.05) with NW and PS, with 15 being optimal. Farrowing BCS had a curvilinear relationship (P 0.05) with NW and PS, with 3.6 being ideal. Farrowing BW had a curvilinear relationship (P 0.05) with LWW and PS, with a BW of 220 and 210 kg, respectively, being optimal. Farrowing LMA had a curvilinear relationship (P 0.05) with WCI, with 51.6 cm<sup>2</sup> being ideal. Results provide sow body condition targets to maximize reproductive throughput. The present study suggests feeding sows to a target sow body condition caliper score of 14 to 15 (representing a back angle of 130˚ to 132.5˚) to maximize sow productivity.展开更多
Body condition score(BCS)is an important management tool in the modern dairy industry,and one of the basic techniques for animal welfare and precision dairy farming.The objective of this study was to use a vision syst...Body condition score(BCS)is an important management tool in the modern dairy industry,and one of the basic techniques for animal welfare and precision dairy farming.The objective of this study was to use a vision system to evaluate the fat cover on the back of cows and to automatically determine BCS.A 3D camera was used to capture the depth images of the back of cows twice a day as each cow passed beneath the camera.Through background subtraction,the back area of the cow was extracted from the depth image.The thurl,sacral ligament,hook bone,and pin bone were located via depth image analysis and evaluated by calculating their visibility and curvature,and those four anatomical features were used to measure fatness.A dataset containing 4820 depth images of cows with 7 BCS levels was built,among which 952 images were used as training data.Taking four anatomical features as input and BCS as output,decision tree learning,linear regression,and BP network were calibrated on the training dataset and tested on the entire dataset.On average,the BP network model scored each cow within 0.25 BCS points compared to their manual scores during the study period.The measured values of visibility and curvature used in this study have strong correlations with BCS and can be used to automatically assess BCS with high accuracy.This study demonstrates that the automatic body condition scoring system has the possibility of being more accurate than human scoring.展开更多
Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the...Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the ISO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RMS) of vertical vibrations. However, the effect of the payload is not considerable on the RMS. Moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.展开更多
Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incid...Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incidence and impact of oral lesions in nestlings of a facultative scavenger species,the black kite Milvus migrans,were examined over seven breeding seasons in the highly degraded environment close to Madrid,Spain.We found an overall prevalence of 31%of nestlings with oral lesions,with no clear spatial pattern in nests with affected and unaffected individuals.The occurrence and number of oral lesions were negatively associated with nestling body condition and brood size.Broods,where all siblings had oral lesions,were smaller than those where some or all siblings were apparently healthy,suggesting that oral disease could be causing nestling mortality and,consequently,brood size reduction.In turn,nestling body condition was negatively affected by lesion occurrence,brood size,and laying date.Although these relationships were bidirectional,piecewise structural equation modeling analyses showed a greater negative effect of body condition on lesion occurrence than vice versa,indicating that nestlings in poorer body condition were more likely to develop oral lesions(which could contribute to aggravate their state of deterioration)than those in better condition.Nestlings from small broods were also more likely to have oral disease(directly or indirectly through their lower body condition)than nestlings from large broods.Nestlings that hatched last in the broods showed greater development stress than those that hatched first.Anthropogenic stressors could trigger poor body condition,and contribute to microbiota dysbiosis-related diseases.Although further research is needed to determine the consequences for the long-term fitness of individuals,actions should be taken to mitigate adverse conditions that may favor the appearance of environmental diseases associatedwithperi-urbanareas,giventheirrapidexpansion overnatural areas.展开更多
The study was conducted to evaluate the fattening performance of Arsi, Borana, Harar and Holstein Friesian crossbred bulls finished under a similar feeding condition at the beef farm in Haramaya University. The averag...The study was conducted to evaluate the fattening performance of Arsi, Borana, Harar and Holstein Friesian crossbred bulls finished under a similar feeding condition at the beef farm in Haramaya University. The average daily weight gain of the four breeds ranges from 0.49 to 0.71 kg. Feed conversion efficiency also ranges from 0.11 - 0.15. Simple linear regression models were used to explore the relationship between live body weight change and change in body condition score as well as seven linear body measurements for all age groups. An average change for a unite of body condition score was equivalent to 20.3, 20.61, 22.42 and 27.78 kg for Borana, Arsi, Harar and Holstein Friesian crossbred bulls respectively. Body condition score was significantly influenced by breeds. There was a significant breed by age interaction effect on the initial body condition score of the four breeds. There was a significant and positive strong association between change in body weight and body condition score. There was a significant and strong correlation between change in body weight and change in Total topline, neck length, heart girth, flank circumference and rump length having correlation coefficients ranges from 0.57 to 0.97. A higher net profit of 7380.47 ETB per head was recorded by Borana bulls followed by Harar bulls, Arsi and Holstein Friesian crossbred with net profit of 5406.86, 5193.29 and 3384.98 ETB per head respectively. Borana bulls are more superior in weight gain and net profit. Bodyweight change could be predicted based on body condition score change during the fattening period.展开更多
Subcutaneous fat deposition has many important roles in dairy cattle,including immunological defense and mechanical protection.The main objectives of this study are to identify key candidate genes regulating subcutane...Subcutaneous fat deposition has many important roles in dairy cattle,including immunological defense and mechanical protection.The main objectives of this study are to identify key candidate genes regulating subcutaneous fat deposition in high-producing dairy cows by integrating genomic and transcriptomic datasets.A total of 1654 genotyped Holstein cows are used to perform a genome-wide association study(GWAS)aiming to identify genes associated with subcutaneous fat deposition.Subsequently,weighted gene co-expression network analyses(WGCNA)are conducted based on RNA-sequencing data of 34 cows and cow yield deviations of subcutaneous fat deposition.Lastly,differentially expressed(DE)m RNA,lnc RNA,and differentially alternative splicing genes are obtained for 12 Holstein cows with extreme and divergent phenotypes for subcutaneous fat deposition.Forty-six protein-coding genes are identified as candidate genes regulating subcutaneous fat deposition in Holstein cattle based on GWAS.Eleven overlapping genes are identified based on the analyses of DE genes and WGCNA.Furthermore,the candidate genes identified based on GWAS,WGCNA,and analyses of DE genes are significantly enriched for pathways involved in metabolism,oxidative phosphorylation,thermogenesis,fatty acid degradation,and glycolysis/gluconeogenesis pathways.Integrating all findings,the NID2,STARD3,UFC1,DEDD,PPP1R1B,and USP21 genes are considered to be the most important candidate genes influencing subcutaneous fat deposition traits in Holstein cows.This study provides novel insights into the regulation mechanism underlying fat deposition in high-producing dairy cows,which will be useful when designing management and breeding strategies.展开更多
Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller （1994） h...Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller （1994） hypothesized that the right testis serves a compensatory role and increases in size when the left one is defective, and further suggested that testes asymmetry may be a reliable indicator of individual body condition. In this paper, we tested the compensation hypothesis in the Guenther＇s frog, Hylarana guentheri. From 60 sampled males, we found that there was a significant directional asymmetry in testes mass, with the left testis size being significantly correlated with relative testes asymmetry, providing evidence that the right testis had a compensatory function. However, testes mass and asymmetry were not correlated with body condition. Hence, we found no evidence that testes asymmetry in the Guenther＇s frog reflected male condition, and male age was also not related to testes mass or asymmetry.展开更多
Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness...Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness.Although direct consumption entails the greatest effect,predators can affect prey by means of other mechanisms.For instance,injuries inflicted by failed predation attempts can jeopardize prey fitness,even beyond the short-term.In anuran tadpoles,failed predation typically results in partial tail loss,which is known to reduce swimming speed.However,the potential consequences of tadpole partial tail loss after metamorphosis remain understudied.Because tail materials could be important in conforming metamorph body,we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes.We clipped 55%tail length of pre-tail-resorption stage anesthetized tadpoles,and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls.Also,we tested whether tail length correlated with metamorph body size of individuals of the control groups.Tailclipped tadpoles produced smaller metamorphs than both controls(the bdy size of metamorphs from both controls was similar),which could incur costs in mid-term survival or time to first reproduction.This effect could be particularly important in areas with introduced predators,if autochthonous tadpoles lack defenses against them.Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body,according to the negative effect of shorter tails in a correlational analysis,and clipped tails in an experimental test,on metamorph body size.展开更多
The compensation hypothesis predicts that if the left testis is defective e.g.due to developmental stress,the increased right testis serves a compensatory role,and thereby displaying testes asymmetry which can be a re...The compensation hypothesis predicts that if the left testis is defective e.g.due to developmental stress,the increased right testis serves a compensatory role,and thereby displaying testes asymmetry which can be a reliable indicator of male body condition.Here,to test the prediction of the compensation hypothesis,we analyzed difference in size between left testis and right testis and the relationship between testes asymmetry and male body condition in the swelled vent frog(Feirana quadranus).We found that the left testis was larger than right testis,displaying a significant directional asymmetry in testes size.Although testes mass was correlated with body condition,testes asymmetry was not correlated with body condition,which cannot provide evidence that the right testis had a compensatory function.Our findings suggest no evidence for the compensation hypothesis in this species due to lacking the compensatory function in right testis.展开更多
The objectives of the current study were to evaluate the estrous response and pregnancy rate following timed artificial insemination (TAI) with frozen-thawed semen in cows. The study was carried out in cows at differe...The objectives of the current study were to evaluate the estrous response and pregnancy rate following timed artificial insemination (TAI) with frozen-thawed semen in cows. The study was carried out in cows at different villages of KwaZulu-Natal (KZN;n = 160) and Limpopo provinces (L;n = 171). Cows were selected randomly as presented by the farmers, regardless of parity, age, breed and body weight following pregnancy diagnosis. The cows were grouped according to breed type and body condition score (BCS) on a scale of 1-5. Selected cows were inserted a controlled intravaginal drug release (CIDR<sup>®</sup>) and removed on day 8, followed by administration of prostaglandin. Heat was observed on day 9 with the aid of heat mount detectors (HMD) that were placed on the individual cow’s tail head. Cows on heat were then inseminated twice at 12 hours interval. Pregnancy diagnosis was performed by an ultrasound scanner and rectal palpation 90 days after TAI. Data were analyzed using SAS 2006. Estrous responses were 100% in KZN and 99% in Limpopo. The lowest pregnancy rate was recorded in Brahman and Bonsmara type cows with BCS ≤ 2.5 regardless of province. Interestingly, Nguni type cows with BCS ≤ 2.5 had higher average pregnancy rate of 59.5% in Limpopo and 53.5% in KZN. However, cows with BCS ≥ 3 had better pregnancy rate regardless of breed type and province. In conclusion, village cows can be synchronized successfully and inseminated with frozen-thawed semen. However, pregnancy rates are low in cows with lower body condition. Village Nguni type cows were not affected by body condition scoring as they had higher and similar pregnancy rate as those that had body condition of ≥3.展开更多
We compared spring-summer activity of adult female Agassiz’s Desert Tortoises (Gopherus agassizii) among three consecutive years (1997, 1998, and 1999) that differed dramatically in winter rainfall and annual plant p...We compared spring-summer activity of adult female Agassiz’s Desert Tortoises (Gopherus agassizii) among three consecutive years (1997, 1998, and 1999) that differed dramatically in winter rainfall and annual plant production at a wind energy facility in the Sonoran Desert of southern California. Winter rainfall was approximately 71%, 190%, and 17% of the long-term average (October-March = 114 mm) for this area in water years (WY) 1997, 1998, and 1999, respectively. The substantial precipitation caused by an El Ni?o Southern Oscillation (ENSO) event in WY 1998 produced a generous annual food plant supply (138.2 g dry biomass/ m2) in the spring. Primary production of winter annuals during below average rainfall years (WY 1997 and WY 1999) was reduced to 98.3 and 0.2 g/m2, respectively. Mean rates of movement and mean body condition indices (mass/length) did not differ significantly among the years. The drought year following ENSO (WY 1999) was statistically similar to ENSO in every other measured value, while WY 1997 (end of a two year drought) was statistically different from ENSO using activity area, minimum number of burrows used, and percentage of non-movements. Our data suggest that female G. agassizii activity can be influenced by environmental conditions in previous years.展开更多
Wild populations are continuously subjected to changes in environmental factors that pose different challenges.Body condition and hormones have been commonly used as health indicators due to their potential correlatio...Wild populations are continuously subjected to changes in environmental factors that pose different challenges.Body condition and hormones have been commonly used as health indicators due to their potential correlation with fitness.In the present study,we analyzed whether habitats of different quality influenced body mass,food intake and physiological stress levels in wild wood mice(Apodemus sylvaticus).Field work was seasonally carried out in Holm oak woods and pine forests in central Spain.A total of 93 wood mice from 4 different populations(2 per habitat type)were live-trapped.From each captured individual we noted body mass and food intake,measured as the amount of bait remaining in each trap.The physiological stress levels were measured non-inva-sively in collected fresh feces by quantifying fecal corticosterone metabolites(FCM)with a 5a-pregnane-3ß,11ß,21-triol-20-one enzyme immunoassay.Wood mice abundances decreased from spring to summer,were higher in Holm oak woods than in pine forests and also resulted in different age-class distribution between both habitats.Individuals inhabiting pine forests showed a lower body mass and increased food intake,probably because of the comparatively lower food quality and availability in this habitat.Furthermore,these individuals showed increased physiological stress levels,likely due to the lower quality habitat in relation to both food and vegetation cover availability.Overall,besides affecting local wood mouse abundance,our study underscores the effect of habitat quality on body mass,food intake and the endocrine stress response.Considering the wood mouse’s piv-otal position in ecosystems,these results could help in the understanding of environmental traits hampering the viability of wild populations.展开更多
Species loss by habitat replacement operating as an ecological filter is a well-known consequence of modern human activities. In contrast, the ecological and evolutionary response of species overcoming those filters i...Species loss by habitat replacement operating as an ecological filter is a well-known consequence of modern human activities. In contrast, the ecological and evolutionary response of species overcoming those filters in convertedhabitats has not been thoroughly explored. Species that persist are subject to novel and potentially stressful conditions that may induce certain morphological changes. We evaluated changes in the functional morphology of threeanuran species persisting after the conversion of areas of the Atlantic Forest into pine plantations. We specificallyevaluated differences in body size and body condition indices, head width, and hind legs’ length between adultindividuals from both habitats and sexes. Habitat conversion and sexual dimorphism affected the morphology ofthe three anurans, with varying effects upon species and traits. Regarding the effect of habitat conversion, Elachistocleis bicolor increased body condition in plantations with no changes in the other traits, Physalaemus cuvierishowed only a marginal increment in residual body mass in plantations, and Odontophrynus americanus exhibiteda substantial increment in body size while maintaining its body condition in plantations. Remarkably, none of theresults suggested these persistent anurans were stressed by forest conversion. This study shows that habitat conversion may induce intraspecific morphological changes in ecologically relevant traits of persistent species, andthat disturbed areas do not necessarily imply stressful, low quality habitats affecting all persistent native speciesnegatively.展开更多
The relationships between vertebrate pests and crop damage are often complex and difficult to study.In palm oil plantations rodents remain the major pests,causing substantial monetary losses.The present study examined...The relationships between vertebrate pests and crop damage are often complex and difficult to study.In palm oil plantations rodents remain the major pests,causing substantial monetary losses.The present study examined the numerical and functional responses of rodents to changes in the availability of oil palm fruit and the damage associated with that response.For the study,200 traps were set in pairs on a 10×10 trapping grid for 3 consecutive nights in each of 6 study plots at 8-week intervals in a 2569 ha oil palm plantation at Labu,Negeri Sembilan state in Peninsular Malaysia over 14 months.A total of 1292 individual rats were captured over 25200 trap-nights.Animals were identified,aged,sexed,weighed and measured.An index of the relative abundance of rats was calculated based on trapping success.Damage to infructescences was assessed at each trap point.Regardless of the age of palms,there were positive and significant relationships between the relative abundance of rats and numbers of infructescences.The levels of damage to infructescences were significantly correlated with the relative abundance of rats.A steep increase in damage was observed with an increase in mature infructescences,indicating a feeding preference of rats for mature infructescences.For both males and females of all rat species,there were weak and non-significant correlations between body condition and infructescence numbers.These results indicated that there was a numerical and a functional response by rats to the availability of palm fruit and a resulting increase in depredation of oil palm fruits.The ways in which this information might aid in future pest control are discussed.展开更多
文摘With the aim of evaluating how changes in the metabolic status in the last month of pregnancy affects reproductive efficiency, forty six Bos indicus multiparous cows (5.5 ± 2.4 parturitions), were used. Measurements of body weight (BW), body condition score (BCS) and dorsal back fat (BF) were taken in the last month of pregnancy, postpartum period previous to synchronization (average 50 d) and at breeding by natural mating following synchronization with a progestin (average 70 d). Average postpartum days to resumption to ovarian activity were 79.96 ± 16.5 d, and average postpartum days to conception was 88.5 ± 14 d. Days postpartum to resumption of the ovarian activity was positively correlated (0.51, P 0.01) with days postpartum to conception, also, days postpartum to conception was positively correlated with prepartum back fat (14 d before parturition) (0.44, P 0.05). It was observed that BF at calving which is an objective measurement had a low correlation with other productive variables such as BCS and BW (always less than 0.39). Body fat might be a more reliable indicator of the current metabolic status of the animal particularly in the last month of pregnancy when the indicators of BCS are somehow more difficult to interpret and subjective.
文摘Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the life cycle of individuals because it is associated with new demands： After leaving the nest, individuals have to find their own food and cope with a new set of previously unknown stressors. In this study, we aimed at better understanding how energetically demanding the post-ftedging period is in house sparrows Passer domesticus by measuring several indices of a fledgling＇s state （body condition, fat and muscle scores and plumage quality）. If the energetic demands of the post-fledging period are greater than those of the adult life, we predicted that fledglings should be in lower condition and should have a plumage of lower quality relative to adults. Supporting this prediction, the condition and the plumage of fledglings differed dramatically from those of adults. Interestingly, this difference disappeared in autumn. Overall, our results suggest that the post-fledging period is probably one of the most energetically demanding of the life cycle in this species. Supporting this idea, the resighting probability of fledglings was lower relative to adults. However, resighting probability depends on many factors （mortality, dispersal, habitat use and behaviours） and future studies are necessary to tease apart their relative importance in determining resighting probability [Current Zoology 60 （4）： 449-459, 2014].
基金Comisión Nacional de Investigación Científica y Tecnológica CONICYT,Gobierno de Chile,for funding his graduate studiesFondo Nacional de Desarrollo Científico y Tecnológico FONDECYT,Gobierno de Chile,supported this research through the proyect Id:1120314。
文摘Despite the widely accepted view that planted forests are valuable habitat for wildlife species,there is a lack of empirical evidence showing the suitability of this novel habitat,especially in relation to plantations of exotic tree species.Furthermore,little is known about the effects of forest management on the ecology and dynamics of wild populations in the Neotropics.During the breeding season,the migrant flycatcher White-crested Elaenia is the most abundant bird species in forested landscapes in Chile.For several years we have studied different aspects of these artificial forests in the coastal range of south-central Chile as habitat for the species,particularly in contrast to the native forest.In general,our results indicate that plantation forests offer a poorer quality habitat,where the density of the species tends to be lower than in the native forest,although a significant edge effect suggests that its quality can be mitigated by planting as a matrix mosaic with native forest.Furthermore,compared to native forests,populations in plantations contained a higher proportion of younger adult individuals maintaining larger territories,and showing poorer body condition.We suggest that these differences could also have an impact on the birds'longevity and survival.
文摘The objective was to quantify relationships between sow body condition and subsequent reproduction. Multiparous sows were measured at breeding (n = 1571) and farrowing (n = 887) on a commercial farm in eastern North Carolina. Sow body condition measures included: sow body condition caliper (CS), weight (BW), backfat, longissimus muscle area (LMA) and visual body condition score (BCS). Sow production traits were: number born alive (NBA), litter birth weight (LBW), number weaned (NW), piglet survival (PS), litter weaning weight (LWW), wean-to-conception interval (WCI), farrowing rate and lactation average daily feed intake. Data were analyzed in SAS using PROC GLM for continuous traits and PROC GLIMMIX for categorical traits. Breeding CS had a curvilinear relationship (P 0.05) with NBA, LBW, NW, PS and WCI, with a CS of 15 being optimal for NBA, NW and PS and 14 ideal for LBW and WCI. Breeding LMA had a curvilinear relationship (P 0.05) with PS, with 51.5 cm<sup>2</sup> maximizing survival. Breeding BCS had a curvilinear relationship (P 0.05) with NBA, LBW, NW, PS and WCI, with 3.2 being optimal for NBA, NW and WCI and 3.0 ideal for LBW and PS. Farrowing CS had a curvilinear relationship (P 0.05) with NW and PS, with 15 being optimal. Farrowing BCS had a curvilinear relationship (P 0.05) with NW and PS, with 3.6 being ideal. Farrowing BW had a curvilinear relationship (P 0.05) with LWW and PS, with a BW of 220 and 210 kg, respectively, being optimal. Farrowing LMA had a curvilinear relationship (P 0.05) with WCI, with 51.6 cm<sup>2</sup> being ideal. Results provide sow body condition targets to maximize reproductive throughput. The present study suggests feeding sows to a target sow body condition caliper score of 14 to 15 (representing a back angle of 130˚ to 132.5˚) to maximize sow productivity.
基金The work was sponsored by the Key R&D and Promotion Projects in Henan Province(Science and Technology Development,No.192102110089)Open Funding Project of Key Laboratory of Equipment and Informatization in Environment Controlled Agriculture,Ministry of Agriculture and Rural Affairs,P.R.China(No.2011NYZD1804)Key Scientific Research Project Plan of Colleges and Universities in Henan Province(No.19A416003).
文摘Body condition score(BCS)is an important management tool in the modern dairy industry,and one of the basic techniques for animal welfare and precision dairy farming.The objective of this study was to use a vision system to evaluate the fat cover on the back of cows and to automatically determine BCS.A 3D camera was used to capture the depth images of the back of cows twice a day as each cow passed beneath the camera.Through background subtraction,the back area of the cow was extracted from the depth image.The thurl,sacral ligament,hook bone,and pin bone were located via depth image analysis and evaluated by calculating their visibility and curvature,and those four anatomical features were used to measure fatness.A dataset containing 4820 depth images of cows with 7 BCS levels was built,among which 952 images were used as training data.Taking four anatomical features as input and BCS as output,decision tree learning,linear regression,and BP network were calibrated on the training dataset and tested on the entire dataset.On average,the BP network model scored each cow within 0.25 BCS points compared to their manual scores during the study period.The measured values of visibility and curvature used in this study have strong correlations with BCS and can be used to automatically assess BCS with high accuracy.This study demonstrates that the automatic body condition scoring system has the possibility of being more accurate than human scoring.
文摘Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the ISO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RMS) of vertical vibrations. However, the effect of the payload is not considerable on the RMS. Moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.
基金supported by projects CGL2009-12753-C02-01/BOS,CGL2010-15726,and PID2019-109685GB-I100 of the Spanish Ministry of Science,Innovation and Universities.
文摘Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens,making the epizootiology of environmental diseases difficult to unravel.The incidence and impact of oral lesions in nestlings of a facultative scavenger species,the black kite Milvus migrans,were examined over seven breeding seasons in the highly degraded environment close to Madrid,Spain.We found an overall prevalence of 31%of nestlings with oral lesions,with no clear spatial pattern in nests with affected and unaffected individuals.The occurrence and number of oral lesions were negatively associated with nestling body condition and brood size.Broods,where all siblings had oral lesions,were smaller than those where some or all siblings were apparently healthy,suggesting that oral disease could be causing nestling mortality and,consequently,brood size reduction.In turn,nestling body condition was negatively affected by lesion occurrence,brood size,and laying date.Although these relationships were bidirectional,piecewise structural equation modeling analyses showed a greater negative effect of body condition on lesion occurrence than vice versa,indicating that nestlings in poorer body condition were more likely to develop oral lesions(which could contribute to aggravate their state of deterioration)than those in better condition.Nestlings from small broods were also more likely to have oral disease(directly or indirectly through their lower body condition)than nestlings from large broods.Nestlings that hatched last in the broods showed greater development stress than those that hatched first.Anthropogenic stressors could trigger poor body condition,and contribute to microbiota dysbiosis-related diseases.Although further research is needed to determine the consequences for the long-term fitness of individuals,actions should be taken to mitigate adverse conditions that may favor the appearance of environmental diseases associatedwithperi-urbanareas,giventheirrapidexpansion overnatural areas.
文摘The study was conducted to evaluate the fattening performance of Arsi, Borana, Harar and Holstein Friesian crossbred bulls finished under a similar feeding condition at the beef farm in Haramaya University. The average daily weight gain of the four breeds ranges from 0.49 to 0.71 kg. Feed conversion efficiency also ranges from 0.11 - 0.15. Simple linear regression models were used to explore the relationship between live body weight change and change in body condition score as well as seven linear body measurements for all age groups. An average change for a unite of body condition score was equivalent to 20.3, 20.61, 22.42 and 27.78 kg for Borana, Arsi, Harar and Holstein Friesian crossbred bulls respectively. Body condition score was significantly influenced by breeds. There was a significant breed by age interaction effect on the initial body condition score of the four breeds. There was a significant and positive strong association between change in body weight and body condition score. There was a significant and strong correlation between change in body weight and change in Total topline, neck length, heart girth, flank circumference and rump length having correlation coefficients ranges from 0.57 to 0.97. A higher net profit of 7380.47 ETB per head was recorded by Borana bulls followed by Harar bulls, Arsi and Holstein Friesian crossbred with net profit of 5406.86, 5193.29 and 3384.98 ETB per head respectively. Borana bulls are more superior in weight gain and net profit. Bodyweight change could be predicted based on body condition score change during the fattening period.
基金the support of founding by the Key Research Project of Ningxia Hui Autonomous Region(2022BBF02017)the earmarked fund for CARS-36the Program for Changjiang Scholar and Innovation Research Team in University(IRT-15R62)。
文摘Subcutaneous fat deposition has many important roles in dairy cattle,including immunological defense and mechanical protection.The main objectives of this study are to identify key candidate genes regulating subcutaneous fat deposition in high-producing dairy cows by integrating genomic and transcriptomic datasets.A total of 1654 genotyped Holstein cows are used to perform a genome-wide association study(GWAS)aiming to identify genes associated with subcutaneous fat deposition.Subsequently,weighted gene co-expression network analyses(WGCNA)are conducted based on RNA-sequencing data of 34 cows and cow yield deviations of subcutaneous fat deposition.Lastly,differentially expressed(DE)m RNA,lnc RNA,and differentially alternative splicing genes are obtained for 12 Holstein cows with extreme and divergent phenotypes for subcutaneous fat deposition.Forty-six protein-coding genes are identified as candidate genes regulating subcutaneous fat deposition in Holstein cattle based on GWAS.Eleven overlapping genes are identified based on the analyses of DE genes and WGCNA.Furthermore,the candidate genes identified based on GWAS,WGCNA,and analyses of DE genes are significantly enriched for pathways involved in metabolism,oxidative phosphorylation,thermogenesis,fatty acid degradation,and glycolysis/gluconeogenesis pathways.Integrating all findings,the NID2,STARD3,UFC1,DEDD,PPP1R1B,and USP21 genes are considered to be the most important candidate genes influencing subcutaneous fat deposition traits in Holstein cows.This study provides novel insights into the regulation mechanism underlying fat deposition in high-producing dairy cows,which will be useful when designing management and breeding strategies.
基金support is provided by the Foundation of Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education,China WesNormal University(XNYB01-3)
文摘Testes size in most animals commonly shows directional asymmetry. In birds, the left testis mass is usually larger than the right one, but the reports on the testes asymmetry in anurans are very few. Moller （1994） hypothesized that the right testis serves a compensatory role and increases in size when the left one is defective, and further suggested that testes asymmetry may be a reliable indicator of individual body condition. In this paper, we tested the compensation hypothesis in the Guenther＇s frog, Hylarana guentheri. From 60 sampled males, we found that there was a significant directional asymmetry in testes mass, with the left testis size being significantly correlated with relative testes asymmetry, providing evidence that the right testis had a compensatory function. However, testes mass and asymmetry were not correlated with body condition. Hence, we found no evidence that testes asymmetry in the Guenther＇s frog reflected male condition, and male age was also not related to testes mass or asymmetry.
文摘Studies on the impacts of variation of biotic interactions at key life cycle stages are crucial to understand the interface between ecological and developmental processes.Predators exert a major impact on prey fitness.Although direct consumption entails the greatest effect,predators can affect prey by means of other mechanisms.For instance,injuries inflicted by failed predation attempts can jeopardize prey fitness,even beyond the short-term.In anuran tadpoles,failed predation typically results in partial tail loss,which is known to reduce swimming speed.However,the potential consequences of tadpole partial tail loss after metamorphosis remain understudied.Because tail materials could be important in conforming metamorph body,we assess the effects of tadpole partial tail loss on metamorph body size in Iberian spadefoot toads Pelobates cultripes.We clipped 55%tail length of pre-tail-resorption stage anesthetized tadpoles,and compared their body size as metamorphs with anesthetized and non-anesthetized non-tail-clipped controls.Also,we tested whether tail length correlated with metamorph body size of individuals of the control groups.Tailclipped tadpoles produced smaller metamorphs than both controls(the bdy size of metamorphs from both controls was similar),which could incur costs in mid-term survival or time to first reproduction.This effect could be particularly important in areas with introduced predators,if autochthonous tadpoles lack defenses against them.Results suggest that materials resorbed from tadpole tail tissues might be reallocated into metamorph body,according to the negative effect of shorter tails in a correlational analysis,and clipped tails in an experimental test,on metamorph body size.
基金the National Natural Sciences Foundation of China(31471996,31772451,31970393)the Key Cultivation Foundation of China West Normal University(17A006)+1 种基金the Science and Technology Youth Innovation Team of Sichuan Province(19CXTD0022)Talent Project of China West Normal University(17YC335)to provide for financial support。
文摘The compensation hypothesis predicts that if the left testis is defective e.g.due to developmental stress,the increased right testis serves a compensatory role,and thereby displaying testes asymmetry which can be a reliable indicator of male body condition.Here,to test the prediction of the compensation hypothesis,we analyzed difference in size between left testis and right testis and the relationship between testes asymmetry and male body condition in the swelled vent frog(Feirana quadranus).We found that the left testis was larger than right testis,displaying a significant directional asymmetry in testes size.Although testes mass was correlated with body condition,testes asymmetry was not correlated with body condition,which cannot provide evidence that the right testis had a compensatory function.Our findings suggest no evidence for the compensation hypothesis in this species due to lacking the compensatory function in right testis.
文摘The objectives of the current study were to evaluate the estrous response and pregnancy rate following timed artificial insemination (TAI) with frozen-thawed semen in cows. The study was carried out in cows at different villages of KwaZulu-Natal (KZN;n = 160) and Limpopo provinces (L;n = 171). Cows were selected randomly as presented by the farmers, regardless of parity, age, breed and body weight following pregnancy diagnosis. The cows were grouped according to breed type and body condition score (BCS) on a scale of 1-5. Selected cows were inserted a controlled intravaginal drug release (CIDR<sup>®</sup>) and removed on day 8, followed by administration of prostaglandin. Heat was observed on day 9 with the aid of heat mount detectors (HMD) that were placed on the individual cow’s tail head. Cows on heat were then inseminated twice at 12 hours interval. Pregnancy diagnosis was performed by an ultrasound scanner and rectal palpation 90 days after TAI. Data were analyzed using SAS 2006. Estrous responses were 100% in KZN and 99% in Limpopo. The lowest pregnancy rate was recorded in Brahman and Bonsmara type cows with BCS ≤ 2.5 regardless of province. Interestingly, Nguni type cows with BCS ≤ 2.5 had higher average pregnancy rate of 59.5% in Limpopo and 53.5% in KZN. However, cows with BCS ≥ 3 had better pregnancy rate regardless of breed type and province. In conclusion, village cows can be synchronized successfully and inseminated with frozen-thawed semen. However, pregnancy rates are low in cows with lower body condition. Village Nguni type cows were not affected by body condition scoring as they had higher and similar pregnancy rate as those that had body condition of ≥3.
基金supported in part by the US Geological Survey,Western Ecological Research Center,Joshua Tree National Park,and the Bureau of Land Management,California Desert DistrictAnalysis and manuscript preparation was supported by the California Energy Commission,Research Development and Demonstration Division,Public Interest Energy Research program(contract#500-09-020)
文摘We compared spring-summer activity of adult female Agassiz’s Desert Tortoises (Gopherus agassizii) among three consecutive years (1997, 1998, and 1999) that differed dramatically in winter rainfall and annual plant production at a wind energy facility in the Sonoran Desert of southern California. Winter rainfall was approximately 71%, 190%, and 17% of the long-term average (October-March = 114 mm) for this area in water years (WY) 1997, 1998, and 1999, respectively. The substantial precipitation caused by an El Ni?o Southern Oscillation (ENSO) event in WY 1998 produced a generous annual food plant supply (138.2 g dry biomass/ m2) in the spring. Primary production of winter annuals during below average rainfall years (WY 1997 and WY 1999) was reduced to 98.3 and 0.2 g/m2, respectively. Mean rates of movement and mean body condition indices (mass/length) did not differ significantly among the years. The drought year following ENSO (WY 1999) was statistically similar to ENSO in every other measured value, while WY 1997 (end of a two year drought) was statistically different from ENSO using activity area, minimum number of burrows used, and percentage of non-movements. Our data suggest that female G. agassizii activity can be influenced by environmental conditions in previous years.
基金an FPU scholarship from the Spanish Ministry of Education and Science(grant number:AP2008-03430).
文摘Wild populations are continuously subjected to changes in environmental factors that pose different challenges.Body condition and hormones have been commonly used as health indicators due to their potential correlation with fitness.In the present study,we analyzed whether habitats of different quality influenced body mass,food intake and physiological stress levels in wild wood mice(Apodemus sylvaticus).Field work was seasonally carried out in Holm oak woods and pine forests in central Spain.A total of 93 wood mice from 4 different populations(2 per habitat type)were live-trapped.From each captured individual we noted body mass and food intake,measured as the amount of bait remaining in each trap.The physiological stress levels were measured non-inva-sively in collected fresh feces by quantifying fecal corticosterone metabolites(FCM)with a 5a-pregnane-3ß,11ß,21-triol-20-one enzyme immunoassay.Wood mice abundances decreased from spring to summer,were higher in Holm oak woods than in pine forests and also resulted in different age-class distribution between both habitats.Individuals inhabiting pine forests showed a lower body mass and increased food intake,probably because of the comparatively lower food quality and availability in this habitat.Furthermore,these individuals showed increased physiological stress levels,likely due to the lower quality habitat in relation to both food and vegetation cover availability.Overall,besides affecting local wood mouse abundance,our study underscores the effect of habitat quality on body mass,food intake and the endocrine stress response.Considering the wood mouse’s piv-otal position in ecosystems,these results could help in the understanding of environmental traits hampering the viability of wild populations.
文摘Species loss by habitat replacement operating as an ecological filter is a well-known consequence of modern human activities. In contrast, the ecological and evolutionary response of species overcoming those filters in convertedhabitats has not been thoroughly explored. Species that persist are subject to novel and potentially stressful conditions that may induce certain morphological changes. We evaluated changes in the functional morphology of threeanuran species persisting after the conversion of areas of the Atlantic Forest into pine plantations. We specificallyevaluated differences in body size and body condition indices, head width, and hind legs’ length between adultindividuals from both habitats and sexes. Habitat conversion and sexual dimorphism affected the morphology ofthe three anurans, with varying effects upon species and traits. Regarding the effect of habitat conversion, Elachistocleis bicolor increased body condition in plantations with no changes in the other traits, Physalaemus cuvierishowed only a marginal increment in residual body mass in plantations, and Odontophrynus americanus exhibiteda substantial increment in body size while maintaining its body condition in plantations. Remarkably, none of theresults suggested these persistent anurans were stressed by forest conversion. This study shows that habitat conversion may induce intraspecific morphological changes in ecologically relevant traits of persistent species, andthat disturbed areas do not necessarily imply stressful, low quality habitats affecting all persistent native speciesnegatively.
基金Live trapping and The project was funded by the Ministry of Science,Technology and Innovation,Malaysia,under the Science Fund(05-01-04-SF0740)carried out with animal ethics approval from the University of Queensland(NRSM/325/08/NRSM).
文摘The relationships between vertebrate pests and crop damage are often complex and difficult to study.In palm oil plantations rodents remain the major pests,causing substantial monetary losses.The present study examined the numerical and functional responses of rodents to changes in the availability of oil palm fruit and the damage associated with that response.For the study,200 traps were set in pairs on a 10×10 trapping grid for 3 consecutive nights in each of 6 study plots at 8-week intervals in a 2569 ha oil palm plantation at Labu,Negeri Sembilan state in Peninsular Malaysia over 14 months.A total of 1292 individual rats were captured over 25200 trap-nights.Animals were identified,aged,sexed,weighed and measured.An index of the relative abundance of rats was calculated based on trapping success.Damage to infructescences was assessed at each trap point.Regardless of the age of palms,there were positive and significant relationships between the relative abundance of rats and numbers of infructescences.The levels of damage to infructescences were significantly correlated with the relative abundance of rats.A steep increase in damage was observed with an increase in mature infructescences,indicating a feeding preference of rats for mature infructescences.For both males and females of all rat species,there were weak and non-significant correlations between body condition and infructescence numbers.These results indicated that there was a numerical and a functional response by rats to the availability of palm fruit and a resulting increase in depredation of oil palm fruits.The ways in which this information might aid in future pest control are discussed.
