Arrival Date Research Articles

Risks of post-traumatic stress disorder among emergency medical technicians who responded to the 2016 Taiwan earthquake

Few studies have explored the field experiences and risk factors related to post-traumatic stress disorder (PTSD) among disaster rescue workers. A 6.4-magnitude earthquake struck southern Taiwan on February 6, 2016. A standardized, paper-based, self-administered survey questionnaire including demographic information, field experiences and the Post-Traumatic Stress Disorder Checklist (PCL) was conducted among emergency medical technicians (EMTs) one month after the earthquake. A multivariate regression model was used to analyze the associations between risk factors and the PCL. A two-sided p value less than 0.05 was considered statistically significant. The survey response rate was 86.1% (447/519). The respondents who exceeded the cut-off points for the re-experience, avoidance, or hyperarousal domains were 11.8%, 2.7%, or 4.7%, respectively. A proportion of 12.7% of respondents met partial PTSD. The personality characteristics of anxiety (p<0.001), perfectionism (p=0.023) and introvert tendency (p=0.002) were significantly correlated with partial PTSD. Emergency medical services (EMS) were significantly associated with partial PTSD than other main tasks (p<0.001). The prevalence of partial PTSD was higher but was not significantly different in the groups of lower educational level, longer EMT careers, earlier arrival date, fewer field working hours, or managing dead people. Both univariate and multivariate logistic regression analyses showed that an anxious personality and EMS as the main task during the missions were significantly associated with PTSD risk. Not only personality characteristics but also the task components could alter the PTSD risks in disasters. A broad realization of these risks may improve the mental outcomes of disaster rescuers.

Climatic conditions during migration affect population size and arrival dates in an Afro‐Palaearctic migrant

Long‐distance migrants are particularly susceptible to climate change because of their multi‐stage life‐cycle, but understanding how climatic conditions at each of these stages influence population dynamics remains a key challenge. Here, we use long‐term data from a UK population of Sand Martins Riparia riparia, a declining Afro‐Palaearctic migrant, to investigate how weather on the wintering grounds and at passage sites impacts population size and arrival date. General linear models revealed that population size increased and arrival date advanced over the study period, and both were predicted by regional climatic variables in the previous winter and on passage. These results add to a growing body of evidence showing that population change in migrant birds is influenced by climatic conditions at all stages of the life cycle.

Breeding, dispersal, migration and conservation of the Black-winged Stilt (Himantopus himantopus) in Hungary

Abstract The Black-winged Stilt was the bird of the year in Hungary in 2019. The population of the species increased from 20–25 breeding pairs to 550–680 pairs from 1980s to the present. 75–85% of the Hungarian population bred on effluent pools for pigs and settling pools at sugar beet factories in the first half of 1990s. There were significantly more breeding pairs in Hungary in 1999 compared to previous years, and finally 871 breeding pairs of Black-winged Stilts were documented in 2000 and the Hungarian population was estimated at 940–960 pairs. There were 550–680 breeding pairs in Hungary between 2015 and 2017. Significantly more clutches had more than five eggs in the sampled colonies during the influx in 2000 than in the egg collections before 1971 or in the sampled colony in 2008 as well. First arrivals reached Hungary between 5 and 20 March (median: 15 March) between 2005 and 2019. These arrival dates fall approximately a month earlier than the former arrival dates in mid-April during the 1980s. 470 Black-winged Stilts were observed in a single flock during post-breeding dispersal, this flock was the largest ever documented in Hungary. Stilts left Hungary by the first half of September in the 1980s, and in contrast, they left Hungary between 27 August and 4 January (median: 19 October) between 2005 and 2019. Recently, the most departure dates fall one and a half to three months later compared to the departure dates in the 1980s. Black-winged Stilts marked in Hungary disperse in the Carpathian Basin during their post-fledging/post-breeding dispersal. Based on ring readings of two individuals, they start to migrate southwest with stopover sites in Italy, but their wintering areas are unknown. Stilts hatched in Portugal (one individual) and France (two individuals) bred in Hungary during the large influxes in 1999 and 2000. Five Black-winged Stilts hatched in Italy were observed later in Hungary and are supposed to be breeders in Hungary in most cases. Furthermore, one individual captured as an adult in Spain and two trapped in Italy were observed in Hungary. The Hungarian population of Black-winged Stilt is threatened by predation on eggs and chicks, drainage of wetlands, and also by human-induced flooding of artificial wetlands (e.g. fishponds). Stilts regularly occupy artificial breeding islands the first years after habitat restoration. The Hungarian population of Black-winged Stilts is increasing due to habitat management with grazing animals, especially with Mangalica ‘Woolly’ Pigs and Water Buffalos.

Sharp Differences in the Timing of Male and Female Spring Arrival in the European Stonechat, Saxicola Rubicola, and the Whinchat, S. Rubetra (Passeriformes, Muscicapidae), in North-Eastern Ukraine

Abstract Protandry, or the arrival of males prior to females to the breeding grounds is a widespread phenomenon in migratory birds though rarely examined in related species in which its manifestation can vary. European Stonechat and Whinchat are such a pair studied with use of individual marking in North-Eastern Ukraine in 1993–2008. An apparent protandry was found in Whinchat but not in European Stonechat. The difference between the arrival dates of male and female Whinchats (6 days) was significant. The mean time span between territory establishment by a male and subsequent pair formation was 10.6 days. By contrast, 38% of the first records of European Stonechats in spring were those of already paired birds and the difference between arrival dates of both sexes was non-significant. The proximate cause of protandry in Whinchat and its’ absence in European Stonechat seems to be the differences (or the lack thereof) in the onset of spring migration. The time lapse between the start of migration of male and female Whinchats originates at African wintering grounds and is maintained en route. The absence of the protandry in European Stonechat is probably a relict behaviour from the residency. The protandry in migratory populations of this species is yet to be developed.

Timing of Invasion by Africanized Bees Coincides with Local Extinction of a Specialized Pollinator of a Rare Poppy in Utah, USA

Abstract The introduction of exotic species can have profound impacts on mutualisms between native species in invaded areas. However, determining whether a new invader has impacted native species depends on accurately reconstructing the invasion timing. The arrival of Africanized honey bees (AHB) in southern Utah at some point between 1994 and 2011 has recently been implicated in the local extinction of Perdita meconis, a native specialist pollinator of an endangered poppy, Arctomecon humilis. Although AHBs were purportedly first detected in southern Utah in 2008, their presence in nearby Nevada, Arizona, and New Mexico by 1998–2001 suggests that they may have been present in Utah much earlier. We refined the arrival date of AHBs in southern Utah by using a molecular marker to determine maternal ancestry of museum specimens collected between 2000 and 2008. We found that AHBs were present in southern Utah from 2000 onwards, advancing the arrival date of this invader by at least 8 years. This lends credence to the hypothesis that AHBs played a critical role in the local extinction of P. meconis in Utah. This work also highlights the importance of vouchering even common species such as honey bees in museum collections to serve future research needs.

Idiosyncratic changes in spring arrival dates of Pacific Northwest migratory birds.

Shifts in the timing of bird migration have been associated with climatic change and species traits. However, climatic change does not affect all species or geographic locations equally. Climate in the Pacific Northwest has shifted during the last century with mean temperatures increasing by 1 °C but little change in total annual precipitation. Few long-term data on migration phenology of birds are available in the Pacific Northwest. We analyzed trends in spring arrival dates from a site in the Oregon Coast Range where nearly daily inventories of birds were conducted in 24 of 29 years. Several species showed statistically significant shifts in timing of first spring arrivals. Six of 18 species occur significantly earlier now than during the initial phase of the study. One species arrives significantly later. Eleven show no significant shifts in timing. We associated trends in spring migration phenology with regional climatic variables, weather (precipitation and temperature), traits of species such as migration strategy, foraging behavior, diet, and habitat use, and regional trends in abundance as indexed by Breeding Bird Survey data. We found no set of variables consistently correlated with avian phenological changes. Post hoc analyses of additional climate variables revealed an association of migratory arrival dates across the 18 species with rainfall totals in northern California, presumably indicating that songbird arrival dates in Oregon are slowed by spring storm systems in California. When only the six species with the most strongly advancing arrival dates were analyzed, winter maximum temperatures in the preceding three winters appeared consistently in top models, suggesting a possible role for food availability early in spring to promote the survival and successful reproduction of the earliest-arriving birds. However, additional data on food availability and avian survival and reproductive success are required to test that hypothesis. Despite the appearance of some climate variables in top models, there remains a mismatch between strongly advancing arrival dates in some songbirds and a lack of clear directional change in those climate variables. We conclude that either some previously unrecognized variable or combination of variables has affected the timing of migration in some species but not others, or the appearance of statistically significant directional changes over time can occur without being driven by consistent environmental or species-specific factors.

Factors influencing plasticity in the arrival-breeding interval in a migratory species reacting to climate change.

Climate change is profoundly affecting the phenology of many species. In migratory birds, there is evidence for advances in their arrival time at the breeding ground and their timing of breeding, yet empirical studies examining the interdependence between arrival and breeding time are lacking. Hence, evidence is scarce regarding how breeding time may be adjusted via the arrival‐breeding interval to help local populations adapt to local conditions or climate change. We used long‐term data from an intensively monitored population of the northern wheatear (Oenanthe oenanthe) to examine the factors related to the length of 734 separate arrival‐to‐breeding events from 549 individual females. From 1993 to 2017, the mean arrival and egg‐laying dates advanced by approximately the same amount (~5–6 days), with considerable between‐individual variation in the arrival‐breeding interval. The arrival‐breeding interval was shorter for: (a) individuals that arrived later in the season compared to early‐arriving birds, (b) for experienced females compared to first‐year breeders, (c) as spring progressed, and (d) in later years compared to earlier ones. The influence of these factors was much larger for birds arriving earlier in the season compared to later arriving birds, with most effects on variation in the arrival‐breeding interval being absent in late‐arriving birds. Thus, in this population it appears that the timing of breeding is not constrained by arrival for early‐ to midarriving birds, but instead is dependent on local conditions after arrival. For late‐arriving birds, however, the timing of breeding appears to be influenced by arrival constraints. Hence, impacts of climate change on arrival dates and local conditions are expected to vary for different parts of the population, with potential negative impacts associated with these factors likely to differ for early‐ versus late‐arriving birds.

Suicide risk among refugees compared with non-refugee migrants and the Swedish-born majority population.

It has been hypothesised that refugees have an increased risk of suicide. To investigate whether risk of suicide is higher among refugees compared with non-refugee migrants from the same areas of origin and with the Swedish-born population, and to examine whether suicide rates among migrants converge to the Swedish-born population over time. A population-based cohort design using linked national registers to follow 1 457 898 people born between 1 January 1970 and 31 December 1984, classified by migrant status as refugees, non-refugee migrants or Swedish-born. Participants were followed from their 16th birthday or date of arrival in Sweden until death, emigration or 31 December 2015, whichever came first. Cox regression models estimated adjusted hazard ratios for suicide by migrant status, controlling for age, gender, region of origin and income. There were no significant differences in suicide risk between refugee and non-refugee migrants (hazard ratio 1.28, 95% CI 0.93-1.76) and both groups had a lower risk of suicide than Swedish born. During their first 5 years in Sweden no migrants died by suicide; however, after 21-31 years their suicide risk was equivalent to the Swedish-born population (hazard ratio 0.94, 95% CI 0.79-1.22). After adjustment for income this risk was significantly lower for migrants than the Swedish-born population. Being a refugee was not an additional risk factor for suicide. Our findings regarding temporal changes in suicide risk suggest that acculturation and socioeconomic deprivation may account for a convergence of suicide risk between migrants and the host population over time. None.

Earlier colony arrival but no trend in hatching timing in two congeneric seabirds (Uria spp.) across the North Atlantic.

A global analysis recently showed that seabird breeding phenology (as the timing of egg-laying and hatching) does not, on average, respond to temperature changes or advance with time (Keogan et al. 2018 Nat. Clim. Change8, 313-318). This group, the most threatened of all birds, is therefore prone to spatio-temporal mismatches with their food resources. Yet, other aspects of the breeding phenology may also have a marked influence on breeding success, such as the arrival date of adults at the breeding site following winter migration. Here, we used a large tracking dataset of two congeneric seabirds breeding in 14 colonies across 18° latitudes, to show that arrival date at the colony was highly variable between colonies and species (ranging 80 days) and advanced 1.4 days/year while timing of egg-laying remained unchanged, resulting in an increasing pre-laying duration between 2009 and 2018. Thus, we demonstrate that potentially not all components of seabird breeding phenology are insensitive to changing environmental conditions.

Drivers of variation in migration behavior for a linked population of long-distance migratory passerine

AbstractDespite advances in tracking technologies, migration strategies remain poorly studied for many small-bodied passerines. Understanding variation within a migration strategy is important as variation impacts a population’s resilience to environmental change. Timing, pathway, and stopovers vary based on intrinsic and extrinsic factors that impact individual migration decisions and capacity. Here, we studied drivers of variation in migration across a linked population of Golden-winged Warbler (Vermivora chrysoptera) using data from 37 light-level geolocators. We tested if behaviors vary in response to extrinsic factors: season, year, and proximity to a large geographic barrier—the Gulf of Mexico—and intrinsic factors: age and wing chord. Spring migration was nearly twice as fast as fall migration, with tightly correlated arrival and departure dates that were consistent among years, in contrast to no correlation or consistency in fall. This aligns with predictions for selection to minimize time spent migrating in spring and a relaxation of that pressure in fall. Twenty-nine birds staged for multiple days (mean: 7.5, SE: 0.6) in stopover habitats before crossing the Gulf of Mexico in spring, but 6 individuals overwintering closer to the Gulf coast forewent the stopover and completed migration 8 days faster. These findings suggest birds capable of crossing the Gulf without a stopover may experience a selective advantage by minimizing total migration time. After crossing the Gulf, individuals reduced travel speed and stopover duration, indicating constraints on movement differ before and after the barrier. Wing chord, but not age, positively predicted the total distance and duration of migration, and neither varied with timing, suggesting migration distance impacts morphology, but strategies do not vary with age. Ultimately, we find undescribed stopover locations south of the Gulf are important for most of the population, while high variation in migration behaviors suggest potential resilience to changing environmental conditions.Causantes de variación en el comportamiento migratorio para una población vinculada de un paseriforme migratorio de larga distancia

Individual Variability in Migration Timing Can Explain Long-Term, Population-Level Advances in a Songbird

Migratory animals may be particularly at-risk due to global climate change, as they must match their timing with asynchronous changes in suitable conditions across broad, spatiotemporal scales. It is unclear whether individual long-distance migratory songbirds can flexibly adjust their timing to varying inter-annual conditions. Longitudinal data for individuals sampled across migration are ideal for investigating phenotypic plasticity in migratory timing programs, but remain exceptionally rare. Using the largest, repeat-tracking data set available to date for a songbird (n=32, purple martin Progne subis), we investigated individual variability in migration timing across 7,000-14,000 kilometre migrations between North American breeding sites and South American overwintering sites. In contrast to previous studies of songbirds, we found broad, within-individual variability between years in the timing of spring departure (0-20d), spring crossing of the Gulf of Mexico (0-20d), and breeding site arrival (0-18d). Spring departure and arrival dates were consistent across years (depart r=0.61; arrive r=0.67), however the lower bounds of confidence intervals spanned 0.5 indicating that this finding should be cautiously interpreted until more data accumulates. Fall migration timing was more variable at the individual level (depart range= 0-19d; gulf crossing range range=1-15d; arrive range=0-24d). Fall arrival date was the least repeatable (r=0.002), perhaps due to timing of this leg being the least resource limited, as purple martins are not territorial in winter and join large communal roosts. High within-individual variability in the timing of this diurnal migrant may reflect the greater influence of environmental and social cues as compared to more solitary, nocturnally migrating songbirds. Further, large, within-individual variability in migration dates (0-24d) suggest that advances in spring arrival dates with climate change that have been reported for multiple songbird species (including purple martins) could potentially be explained by intra-individual flexibility in migration timing. However, whether phenotypic plasticity will be sufficient to keep up with the pace of climate change remains to be determined.

Anti-parasite treatment results in decreased estimated survival with increasing lead (Pb) levels in the common eider Somateria mollissima.

Field experiments where parasites are removed through treatment and contaminant levels in host tissues are recorded can provide insight into the combined effects of parasitism and contaminants in wild populations. In 2013 and 2014, we treated northern common eider ducks (Somateria mollissima) arriving at a breeding colony with either a broad-spectrum antihelminthic (PANACUR®) or distilled water, and measured their blood lead (Pb) levels. Breeding propensity and clutch sizes were inversely related to Pb in both treatment groups. In comparison, a negative effect of Pb on resight probability the following year was observed only in the anti-parasitic treatment (APT) group. These contrasting patterns suggest a long-term benefit to survival of intestinal parasitism in eiders experiencing Pb exposure. The arrival date of hens explained some, but not all, of the effects of Pb. We weigh the merits of different hypotheses in explaining our results, including protective bioaccumulation of Pb by parasites, condition-linked thresholds to costly reproduction and the direct effects of APT on eider health. We conclude that variation in helminth parasitism influences survival in this migratory bird in counterintuitive ways.

Evaluation of EPAS1 variants for association with bovine congestive heart failure

Background: Bovine congestive heart failure (BCHF) has become increasingly prevalent in feedlot cattle in the Western Great Plains of North America. BCHF is an untreatable complex condition involving pulmonary hypertension that culminates in right ventricular failure and death. A protein variant of hypoxia-inducible factor 2 alpha (HIF2α, encoded by the endothelial PAS domain-containing protein 1 gene, EPAS1) was previously reported to be associated with pulmonary hypertension at altitudes exceeding 2,000 m. Our aim was to evaluate EPAS1 haplotypes for association with BCHF in feedlot cattle raised at moderate altitudes (1,200 m). Methods: Paired samples of clinical cases and unaffected controls were collected at four feedlots in Nebraska and Wyoming. Each pair (n =102) was matched for source, pen, breed type, sex, arrival date, and management conditions. Cases were identified by animal caretakers, euthanized, and diagnosis was confirmed at necropsy. Cases were derived from 30 different ranch operations, with the largest source contributing 32. Animals were tested for eight EPAS1 haplotypes encoding 36 possible different diploid combinations. Results: The common, ancestral EPAS1 haplotype encoding HIF2α with alanine (A) at position 606 and glycine (G) at position 610 was equally frequent in cases and controls (0.67). The EPAS1 variant haplotype reported to be associated with disease (encoding threonine (T) at position 606 and serine (S) at position 610) was not enriched in cases compared with controls (0.21 and 0.25, respectively). Frequencies of other EPAS1 haplotypes (e.g., encoding Q270, L362, or G671) were each less than 0.05 overall. McNemar’s test with 45 discordant pairs showed the linked T606/S610 variant was not associated with BCHF (OR = 0.73, CI 95 0.38 -1.4, p-value = 0.37). Conclusions: HIF2α polypeptide variants were not significantly associated with BCHF in feedlot cattle at moderate altitudes. Thus, a wider search is needed to identify genetic risk factors underlying this disease.

Interindividual variation and consistency of migratory behavior in the Eurasian woodcock

Diverse spatio-temporal aspects of avian migration rely on relatively rigid endogenous programs. However, flexibility in migratory behavior may allow effective coping with unpredictable variation in ecological conditions that can occur during migration. We aimed at characterizing inter- and intraindividual variation of migratory behavior in a forest-dwelling wader species, the Eurasian woodcock Scolopax rusticola, focusing on spatio-temporal consistency across repeated migration episodes. By satellite-tracking birds from their wintering sites along the Italian peninsula to their breeding areas, we disclosed a remarkable variability in migration distances, with some birds flying more than 6,000 km to Central Asian breeding grounds (up to 101°E). Prebreeding migration was faster and of shorter duration than postbreeding migration. Birds moving over longer distances migrated faster during prebreeding migration, and those breeding at northernmost latitudes left their wintering areas earlier. Moreover, birds making longer migrations departed earlier from their breeding sites. Breeding site fidelity was very high, whereas fidelity to wintering areas increased with age. Migration routes were significantly consistent, both among repeated migration episodes and between pre- and postbreeding migration. Prebreeding migration departure date was not significantly repeatable, whereas arrival date to the breeding areas was highly repeatable. Hence, interindividual variation in migratory behavior of woodcocks was mostly explained by the location of the breeding areas, and spatial consistency was relatively large through the entire annual cycle. Flexibility in prebreeding migration departure date may suggest that environmental effects have a larger influence on temporal than on spatial aspects of migratory behavior.

Sex-Specific Spatiotemporal Variation and Carry-Over Effects in a Migratory Alpine Songbird

For migratory animals, events at one stage of the annual cycle can produce constraints or benefits that carry over to subsequent stages. Differing life-history strategies among individuals can influence the expression of these carry-over effects, leading to pronounced within-population variation in migration. For example, reproductive roles can drive spatiotemporal segregation during the non-breeding season and promote sex-specific carry-over effects, such as reproductive effort affecting autumn migration behaviour. For an alpine breeding population of horned larks Eremophila alpestris in northern British Columbia, Canada, we addressed sex-specific variation in migration behaviour and carry-over effects during both autumn and spring migration using light-level geolocators. Males spent more time farther north and arrived an average of 6 days earlier at the breeding site in spring. Females delayed autumn departure following greater reproductive effort, in turn demonstrating flexible migration behaviour by increasing migration speed and decreasing stopover use. Males maintained autumn migration behaviour regardless of reproductive effort or departure date. Finally, both sexes used staging areas in spring (average stopover = 41 days), with consequences for breeding success. Individuals that used staging areas during spring migration exhibited greater nest success and produced 1.8 more fledglings on average than those that migrated directly from their winter site. Consistent use of staging areas may allow individuals to monitor environmental conditions and optimize their breeding arrival date to acquire high-quality territories while avoiding the cost of arriving too early in a harsh alpine habitat. Overall, our results indicate: (1) sex-specific flexibility in migration strategies that carry-over to and from the reproductive period, and (2) spring staging areas may be a critical component of the annual life-cycle for alpine breeding larks. These behaviours may be particularly important for alpine and arctic birds because the stochastic nature of their breeding habitat likely selects for flexible responses to prevailing conditions.

Progressive delays in the timing of sardine migration in the southwest Indian Ocean

Phenological shifts represent one of the most robust bioindicators of climate change. While considerable multidecadal records of plant and animal phenology exist for the northern hemisphere, few noteworthy records are available for the southern hemisphere. We present one of the first phenological records of fish migration for the southern hemisphere, and one of the only phenological records for the southwest Indian Ocean. The so-called ‘sardine run’ – an annual winter migration of sardines, northeast of their summer spawning grounds on the Agulhas Bank off the coast of Durban, South Africa – has been well documented in local newspapers given the importance placed on fishing and fishing-tourism in the region. An analysis of the first arrival dates of sardines reveals a 1.3 day per decade delay over the period 1946–2012. Although this phenological shift reveals a poor association with sea surface temperatures (SST), it coincides with a poleward shift in the position of the 21 °C mean annual SST isotherm – the threshold temperature for sardine populations. The timing of sardine arrivals near Durban corresponds closely with the number of mid-latitude cyclones passing over the Durban coastline during the months of April and May. The strength of the run is strongly associated with ENSO conditions. The complex suite of factors associated with this phenological shift poses challenges in accurately modelling the future trajectory for this migratory event.&#x0D; Significance:&#x0D; &#x0D; The sardine run, a significant event for tourism and fisheries, is occurring progressively later in the year.&#x0D; The incidence of failed sardine runs has increased in frequency over the period 1946–2012.&#x0D; These changes in fish migration phenology coincide with a poleward shift in the position of the 21 °C mean annual SST isotherm.&#x0D; The strength in the sardine run is strongly associated with ENSO conditions.&#x0D;

220 A comparison of synovex one alone to synovex choice followed by synovex plus as implant strategies for finishing heifers

Abstract A commercial feedyard study utilizing crossbred heifers (n = 1,737; initial BW 313 kg) fed for 182 days compared the effect of two implant strategies on performance and carcass characteristics. The study design was a randomized complete block with block as arrival date and initial BW; with pen as the experimental unit (12/treatment). Heifers were implanted with Synovex ONE Feedlot [200 mg trenbolone acetate (TBA), 28 mg estradiol benzoate (EB)] on d 1 (ONE), or implanted with Synovex Choice (100 mg TBA, 14 mg EB) on d 1 followed by Synovex Plus (200 mg TBA, 28 mg EB) on d 95 (CH/Plus). Statistical analysis was conducted using the Mixed procedure of SAS with treatment and block considered fixed effects for performance. Quality grade (QG) and yield grade (YG) data were analyzed using the GLIMMIX procedure of SAS. Implanting with Ch/PLUS tended to improve ADG and HCW (P ≤ 0.13) compared to implanting with ONE. Heifers implanted using ONE tended (P = 0.09) to have greater DMI than CH/PLUS heifers. Intakes were similar (P = 0.34) between treatments before re-implanting, but CH/Plus heifers had lower (P &lt; 0.01) DMI in the final 85 days. Heifers implanted using CH/PLUS had significantly (P &lt; 0.01) greater G:F calculated on a carcass basis compared to heifers implanted with ONE. Heifers implanted with CH/PLUS had significantly (P ≤ 0.02) lower marbling score and YG, higher dressing percentage, and greater LM area compared to heifers implanted with ONE. Heifers implanted with ONE tended to have improved QG distribution (P = 0.06) but poorer YG distribution (P = 0.09) compared to heifers implanted using CH/PLUS. These data suggest that implanting heifers with Synovex ONE Feedlot resulted in slightly less efficiency but better quality grade when fed equal days compared with using Synovex Choice and Plus reimplant program.

Evaluation of EPAS1 variants for association with bovine congestive heart failure.

Background: Bovine congestive heart failure (BCHF) has become increasingly prevalent in feedlot cattle in the Western Great Plains of North America. BCHF is an untreatable complex condition involving pulmonary hypertension that culminates in right ventricular failure and death. A protein variant of hypoxia-inducible factor 2 alpha (HIF2α, encoded by the endothelial PAS domain-containing protein 1 gene, EPAS1) was previously reported to be associated with pulmonary hypertension at altitudes exceeding 2,000 m. Our aim was to evaluate EPAS1 haplotypes for association with BCHF in feedlot cattle raised at moderate altitudes (1,200 m). Methods: Paired samples of clinical cases and unaffected controls were collected at four feedlots in Nebraska and Wyoming. Each pair (n =102) was matched for source, pen, breed type, sex, arrival date, and management conditions. Cases were identified by animal caretakers, euthanized, and diagnosis was confirmed at necropsy. Cases were derived from 30 different ranch operations, with the largest source contributing 32. Animals were tested for eight EPAS1 haplotypes encoding 36 possible different diploid combinations. Results: The common, ancestral EPAS1 haplotype encoding HIF2α with alanine (A) at position 606 and glycine (G) at position 610 was equally frequent in cases and controls (0.67). The EPAS1 variant haplotype reported to be associated with disease (encoding threonine (T) at position 606 and serine (S) at position 610) was not enriched in cases compared with controls (0.21 and 0.25, respectively). Frequencies of other EPAS1 haplotypes (e.g., encoding Q270, L362, or G671) were each less than 0.05 overall. McNemar's test with 45 discordant pairs showed the linked T606/S610 variant was not associated with BCHF (OR = 0.73, CI 95 0.38 -1.4, p-value = 0.37). Conclusions: HIF2α polypeptide variants were not significantly associated with BCHF in feedlot cattle at moderate altitudes. Thus, a wider search is needed to identify genetic risk factors underlying this disease.

Length polymorphisms at two candidate genes explain variation of migratory behaviors in blackpoll warblers (Setophaga striata).

Migratory behaviors such as the timing and duration of migration are genetically inherited and can be under strong natural selection, yet we still know very little about the specific genes or molecular pathways that control these behaviors. Studies in candidate genes Clock and Adcyap1 have revealed that both of these loci can be significantly correlated with migratory behaviors in birds, though observed relationships appear to vary across species. We investigated geographic genetic structure of Clock and Adcyap1 in four populations of blackpoll warblers (Setophaga striata), a Neotropical–Nearctic migrant that exhibits geographic variation in migratory timing and duration across its boreal breeding distribution. Further, we used data on migratory timing and duration, obtained from light‐level geolocator trackers to investigate candidate genotype–phenotype relationships at the individual level. While we found no geographic structure in either candidate gene, we did find evidence that candidate gene lengths are correlated with five of the six migratory traits. Maximum Clock allele length was significantly and negatively associated with spring arrival date. Minimum Adcyap1 allele length was significantly and negatively associated with spring departure date and positively associated with fall arrival date at the wintering grounds. Additionally, we found a significant interaction between Clock and Adcyap1 allele lengths on both spring and fall migratory duration. Adcyap1 heterozygotes also had significantly shorter migration duration in both spring and fall compared to homozygotes. Our results support the growing body of evidence that Clock and Adcyap1 allele lengths are correlated with migratory behaviors in birds.

No detectable effect of light-level geolocators on the behaviour and fitness of a long-distance migratory seabird

Light-level geolocators are increasingly popular devices for tracking migratory birds. However, to ensure that data on migratory behaviour represent natural behaviour that is not affected by potentially harmful effects of carrying such a device, their effects on behaviour and fitness should be assessed. A review of studies that tested for effects of tarsus-mounted light-level geolocators on seabirds showed that results are equivocal and often difficult to interpret due to the inclusion of only few traits and/or the lack of a proper experimental design. We therefore experimentally tested whether tarsus-mounted light-level geolocators affected a long-distance migratory seabird, the Common Tern Sterna hirundo. Using a well-matched treatment and control group, including both males and females, we tested whether light-level geolocators, deployed in the second half of incubation, affected the subsequent share of incubation, provisioning rate, reproductive performance, phenology or survival of tagged birds or their partners. In the year of deployment, we found no evidence for the behaviour of tagged birds or their partners to be affected by the geolocators. Moreover, we found no effect on their reproductive performance and departure date from the breeding colony. Finally, neither local survival to the next season, nor arrival date to the breeding colony in that season differed between tagged birds or their partners and control birds. These results suggest that a year of carrying a light-level geolocator attached to the tarsus has negligible effects on Common Terns and that such a device can be used to study their migratory behaviour without causing problems or introducing bias.