Measures Of Body Condition Research Articles

Automated body length and body condition measurements of whales from drone videos for rapid assessment of population health

AbstractMonitoring body length and body condition of individuals helps determine overall population health and assess adaptation to environmental changes. Aerial photogrammetry from drone‐based videos is a valuable method for obtaining body length and body condition measurements of cetaceans. However, the laborious manual processing of drone‐based videos to select frames to measure animals ultimately delays assessment of population health and hinders conservation actions. Here, we apply deep learning methods to expedite the processing of drone‐based videos to improve efficiency of obtaining important morphological measurements of whales. We develop two user‐friendly models to automatically (1) detect and output frames containing whales from drone‐based videos (“DeteX”) and (2) extract body length and body condition measurements from input frames (“XtraX”). We use drone‐based videos of gray whales to compare manual versus automated measurements (n = 86). Our results show automated methods reduced processing times by one‐ninth, while achieving similar accuracy as manual measurements (mean coefficient of variation <5%). We also demonstrate how these methods are adaptable to other species and identify remaining challenges to help further improve automated measurements in the future. Importantly, these tools greatly speed up obtaining key morphological data while maintaining accuracy, which is critical for effectively monitoring population health.

PSI-9 Relationship of body condition measures and boar reproductive performance

Abstract In the swine industry, boar nutritional requirements are not well characterized; thus, boars are typically fed to maintain a specific body condition score (BCS). Assessing body condition with subjective scoring can lead to over or underfeeding, which may have repercussions on sperm production and(or) quality. There are objective tools to assess body condition in live boars, like backfat (BF) thickness measured with real-time ultrasound, the Knauer caliper, and flank-to-flank (F2F) length. The relationship of sperm production and quality with BCS has not been reported in modern genetics and modern boar studs. The purpose of this study was to evaluate the relationship of body condition measures with boar reproductive performance. Data collected in March 2023 on commercial boars (n = 147) included a BCS ranging from 2.25 to 3.5, ultrasound backfat (13.7 ± 4.37 mm) performed by a trained technician, body weight (BW; 222 ± 30.2 kg) estimated using heart girth and body length from poll to tailhead, F2F length (106.03 ± 5.94 cm) and Knauer caliper score (17.5 ± 2.37). Additional variables considered were boar genetic line, age, and collection frequency. Sperm production data (total motility, 92.1 ± 7.22%; concentration, 36.7 ± 12.10 mil/mL; ejaculate volume, 231.1 ± 73.72 mL; normal cells, 83.4 ± 11.27%) were obtained from the six collections immediately prior to body condition evaluation. Data were evaluated with the glmmTMB package of R Statistical Software using a generalized linear mixed model. There were no significant relationships between motility or ejaculate volume and boar body condition. Backfat depth was related to percentage of normal cells (P = 0.029) and inversely related to sperm concentration (P = 0.035). There was a tendency for boars with greater F2F to have greater sperm concentration (P = 0.090). Generally, the percentage of normal cells decreased with increasing BCS, though due to the low number of observations in the lower categories, only BCS 3.25 and BCS 3.5 boars were found to have a significant relationship with the trait (P = 0.004 and P = 0.022, respectively). Caliper measure was not related with any sperm parameters. While accessible tools are necessary for consistent management of boars, BF thickness measured by ultrasound was the only objective tool in this study with a significant relationship to any sperm parameters assessed. Measuring BF with ultrasound may not be practical for everyday use. More research should be done to further assess body condition measurements, objective measuring tools, and boar sperm production.

Effects of Body Condition, Anatomical Measurement, and Age on the Cumulative Number of Individual Egg Production and Laying Pattern in First Laying Hens

The individual egg production capacity of laying hens plays an outstanding role in achieving total production within a flock, which is affected by several internal and external factors. This study aimed to evaluate the effect of body condition, anatomical measurement, and age at the first laying (AFL) on the cumulative number of individual egg production (CNIEP) and laying pattern. Therefore, 172 Isa Brown laying chickens were investigated. Data on body condition and anatomical measurement were collected at the age of 16 weeks, while data on production was collected during 21 weeks of production (18-39 weeks). The obtained data were analyzed by Partial Least Square- Structural Equation Modeling (PLS-SEM) using smartPLS. The findings revealed that CNIEP could be predicted by body condition, anatomical measurement, and AFL. Compared to body condition and anatomical measurements, AFL was the most prominent factor in CNIEP. Body condition, anatomical measurement, AFL, and CNIEP had weak effects on the Isa Brown laying chickens’ patterns. Keywords: Anatomical measurement, Individual egg production, Laying pattern

Hubungan Kebiasaan Sarapan dan Aktivitas Fisik dengan Status Gizi Remaja di SMP Negeri 6 Kupang

Nutritional status is a condition or measure of a person's body condition caused by a balance between intake of nutrients from food and nutritional needs. Adolescents are one of the groups at risk for nutritional problems. Nutritional problems in adolescents can be caused by food intake, physical activity, economy, social, and culture. This research was conducted at SMP Negeri 6 Kupang, Alak Sub-district, Kupang City. This research was purposed to analyze the correlation between breakfast habits and physical activity with the nutritional status of adolescents at SMP Negeri 6 Kupang (state junior high school). This research is a correlational analysis and the design approach is a cross-sectional study, with a sample of 100 students which consist of students in grades VII, VIII and IX. The instruments used in this research were nutritional status measurement sheet, breakfast habit questionnaire, PAL (Physical Activity Level), and antropometric measurement (body weight and height). The results of research using the Spearman's Rank Correlation Test show that there is a significant relationship between breakfast habits (p = 0.000 < 0.05) and nutritional status of adolescents and has a level correlation coefficient of 0.594 or sufficient. Meanwhile, there is no significant relationship between physical activity and nutritional status (p=0.940 > 0.05) and has a correlation coefficient of -0.008 or very weak. In conclusion, that breakfast habits are related to the nutritional status of adolescents, where as physical activity is not related to nutritional status of adolescents.

PSIX-26 Reproductive Management Practices for Beef Cow-Calf Producers in Virginia: a Survey

Abstract The Virginia Master Cattlemen (VMC) is an extension program with the goal of educating beef cattle producers on best practices and management. Reproduction management strategies are essential in ensuring beef cow-calf producers achieve one healthy calf, per cow, every year. Every year, during the VMC, a survey on reproductive management practices and adoption of technologies is performed as a representation of current practices of beef cow-calf producers. Over three years (2021-2023), we obtained data from a total of 276 producers in VA. Out of all participants, 71.74% indicated that they had a defined breeding season. Of those, 33.17% had a breeding season of 70 days or less. Furthermore, 47.81% of producers had both a Fall and Spring breeding season, while 24.12% and 28.07% of participants designated their breeding seasons as either Fall or Spring, respectively. Moreover, 62.28% of participants reported that 40% or more of their cows calve within the first 21 days of the calving season. The bull-to-cow ratio was assessed on operations electing to use natural service, with 71.27% of producers having a minimum of a 1:25 bull-to-cow ratio. A total of 66.54% of the participants reported regularly measuring body condition score of their cows. Over the three years, the most adopted reproductive practice on farms was pregnancy diagnosis, with 31.13% of producers indicating they perform pregnancy diagnosis on their herds every year. The second most utilized practice is the bull breeding soundness exam, with 26.11%. Artificial insemination is continuously gaining popularity, with 19.44% of producers reporting they artificially inseminated their cattle over the past three years. Additionally, 15% of producers reported estrus synchronization of their cattle. However, embryo transfer and sexed semen are the two reproductive practices that were least adopted by producers, with 3.72% and 4.60%, respectively. Overall, compared with the 2017 USDA NAHMS cow-calf report, Virginia producers are more advanced with their reproductive management practices compared with the average cattlemen in the United States.

PSVII-2 The Impact of Genomic Information Inclusion on Breeding Value Prediction for a Novel Parasite Resistance Indicator Trait in Brazilian Anglo-Nubian Goats: a Pilot Study

Abstract Infection by Haemonchus contortus is the gastrointestinal parasitosis of greatest economic and social importance in the production of goats, being the leading cause of mortality in the Brazilian goat industry. Genetic selection for resistance to parasites in Anglo-Nubian goats has proven to be a viable alternative to traditional methods of controlling gastrointestinal nematodes, producing animals genetically superior in resistance to parasites. This study aimed to evaluate the impact of including genomic information on the estimation of variance components, genetic parameters, and predictive accuracy of genetic values for the new trait Parasitic Resistance (PR) in Anglo-Nubian goats. The PR is generated by measuring Body Condition Score, FAMACHA chart (ranging from 1 to 5), and Fecal Egg Count on a regular scale. These three traits were used as input variables in the CAPRIOVI software, which uses fuzzy logic to create the PR score, ranging from 0 to 10. Animals with lower scores are more likely to be parasitized and require treatment, while animals with higher scores are less likely to be infected. We used information from 352 animals, totaling 3,855 repeated measurements of PR over the years (2001 to 2020) and 1,500 animals in the pedigree. Animals with less than three measurements for any of the three input traits were removed from the dataset. Contemporary groups were built from information from the year of birth, data collection season, birth season, and physiological stage of the animal, considered as fixed effects, and age at the time of data collection as a covariate in an animal repeatability model. A total of 89 animals were genotyped using the Bead Chip Goats SNP50. After quality control, the remaining 38,659 SNPs (Table 1) were used to build the hybrid matrix (H). The variance components (VC) were estimated using the Bayesian Gibbs Sampling method, and breeding values were predicted using the Best Linear Unbiased Prediction (BLUP) and single-step Best Linear Unbiased Prediction (ssGBLUP) methods. The additive genetic variance and heritability estimation ranged from 0.13 to 0.14 and 0.04 to 0.05, respectively (Table 2). The accuracies obtained for PR with BLUP and ssGBLUP were 0.12 and 0.14, respectively, representing a gain of 16.7%. The genomic information (25 % of all animals with phenotypes) with the repeated records improved the predictive model capability based on accuracy. It also improved the VC estimation for PR in Anglo-Nubian goats raised in the Brazilian semi-arid region. These results highlight the positive impact of genetic evaluation of goats for PR, even with few phenotypes and genotyped animals. In addition to elucidating the additive genetic influence of parasite resistance, it can be a great source of information on the selection and production of Anglo-Nubian goats.

Cost of migration and migratory timing in Western Australian humpback whales

AbstractMigratory humpback whales (Megaptera novaeangliae) cover the cost of reproduction in low‐latitude breeding grounds with stored energy accumulated from polar feeding grounds. The ability to accumulate sufficient energy reserves during feeding periods is vital for key life history stages during migration, including mating, calving, and lactation. This study aimed to investigate the relationship between migration timing and body condition of Western Australian humpback whales. We used unmanned aerial vehicles to measure body condition (residual of body volume vs. length) in 2017 and 2021. Morphometric measurements were obtained from 460 individuals (71 calves, 83 juveniles, 235 adults, and 71 lactating females) during the northbound (toward breeding grounds) and southbound (toward feeding grounds) migration between May and November. Body condition decreased by 23 and 13 percentage points for juveniles and adults, respectively. The body condition of juveniles was shown to be correlated with migration timing for their northern migration, with individuals in better body condition migrating to the breeding grounds earlier. While stored energy is vital for humpback whales to successfully complete their vast migration to‐and‐from breeding grounds, we found no evidence that body condition affects the migration timing for adults, lactating females, and calves.

Beyond body condition: Experimental evidence that plasma metabolites improve nutritional state measurements in a free-living seabird

The ability to efficiently measure the health and nutritional status of wild populations in situ is a valuable tool, as many methods of evaluating animal physiology do not occur in real-time, limiting the possibilities for direct intervention. This study investigates the use of blood plasma metabolite concentrations, measured via point-of-care devices or a simple plate reader assay, as indicators of nutritional state in free-living seabirds. We experimentally manipulated the energy expenditure of wild black-legged kittiwakes on Middleton Island, Alaska, and measured the plasma concentrations of glucose, cholesterol, B-hydroxybutyrate, and triglycerides throughout the breeding season, along with measures of body condition (size-corrected mass [SCM] and muscle depth). Supplemental feeding improved the nutritional state of kittiwakes by increasing feeding rate (higher glucose and triglycerides, lower cholesterol), and flight-handicapping caused a slight nutritional decline (lower glucose and triglycerides, higher cholesterol and B-hydroxybutyrate). Glucose and triglycerides were the best indicators of nutritional state when used alongside SCM, and improved upon commonly used metrics for measuring individual condition (i.e. SCM or mass alone). Metabolite concentrations varied across the breeding period, suggesting that the pre-laying stage, when feeding rates tend to be lower, was the most nutritionally challenging period for kittiwakes (low glucose, high cholesterol). Muscle depth also varied by treatment and breeding stage, but differed from other nutritional indices, suggesting that muscle depth is an indicator of exercise and activity level rather than nutrition. Here we demonstrate potential for the use of blood plasma metabolites measured via point-of-care devices as proxies for evaluating individual health, population health, and environmental food availability.

Visually assessed body condition shows high heritability in a pedigreed great ape population.

Body condition, a measure for relative fat mass, is associated with primate health, fitness, and overall welfare. Body condition is often influenced by dietary factors, age, and/or sex, but several body condition measures (body weight, weight-to-height ratios, and so on) also show high heritability across primate species, indicating a role of genetic effects. Although different measures for body condition exist, many require direct handling of animals, which is invasive, time-consuming, and expensive, making them impractical in wild and captive settings. Therefore, noninvasive visual body condition score (BCS) systems were developed for various animal species, including macaques and chimpanzees, to visually assess relative fat mass. Here we evaluate the utility of a visual BCS system in bonobos by assessing (1) inter-rater reliability, (2) links with body mass, a traditional hands-on measure of condition, and (3) the factors driving individual variation in BCS. We adapted the chimpanzee BCS system to rate 76 bonobos in 11 European zoos (92% of the adult population). Inter-rater reliability was high (s* = 0.948), BCSs were positively associated with body mass (β = 0.075) and not predicted by diet, sex, or age, nor were they associated with a higher abundance of obesity-related diseases. Instead, BCSs showed high levels of heritability (h2 = 0.637), indicating that a majority of body condition variation in bonobos is attributable to genetic similarity of the individuals. This is in line with reported h2 -values for traditional body condition measures in primates and provides support for the reliability of visual BCS systems in great apes. The results of this study emphasize an often unanticipated role of genetics in determining primate body fat and health that has implications for the management of captive primates. Application of this tool in wild populations would aid to unravel environmental from genetic drivers of body condition variation in primates.

Cardiac remodeling caused by cold acclimation is reversible with rewarming in zebrafish (Danio rerio)

Cold acclimation of zebrafish causes changes to the structure and composition of the heart. However, little is known of the consequences of these changes on heart function or if these changes are reversible with rewarming back to the initial temperature. In the current study, zebrafish were acclimated from 27℃ to 20°C, then after 17 weeks, a subset of fish were rewarmed to 27°C and held at that temperature for 7 weeks. The length of this trial, 23 weeks, was chosen to mimic seasonal changes in temperature. Cardiac function was measured in each group at 27°C and 20°C using high frequency ultrasound. It was found that cold acclimation caused a decrease in ventricular cross-sectional area, compact myocardial thickness, and total muscle area. There was also a decrease in end-diastolic area with cold acclimation that reversed upon rewarming to control temperatures. Rewarming caused an increase in the thickness of the compact myocardium, total muscle area, and end-diastolic area back to control levels. This is the first experiment to demonstrate that cardiac remodeling, induced by cold acclimation, is reversible upon re-acclimation to control temperature (27°C). Finally, body condition measurements reveal that fish that had been cold-acclimated and then reacclimated to 27°C, were in poorer condition than the fish that remained at 20°C as well as the control fish at week 23. This suggests that the physiological responses to the multiple changes in temperature had a significant energetic cost to the animal. Summary statementThe decrease in cardiac muscle density, compact myocardium thickness and diastolic area in zebrafish caused by cold acclimation, was reversed with rewarming to control temperatures.

118 Relationship between age, gender, height, body condition score, and body weight in Thoroughbred yearlings raised in Kentucky

Forty years ago, Henneke and coworkers developed a body condition score (BCS) system for horses that is widely used today. This system applies a score of 1 to an emaciated horse and a score of 9 to an extremely obese horse. The system was originally designed to measure BCS in Quarter Horse broodmares, but it has subsequently been adapted to measure body condition in horses of all breeds and life stages. The NRC (2007) suggests that weight gain of 16 to 20 kg will increase the body condition of a 500-kg horse from a 4 to a 5. There is little information regarding the relationship between BCS and weight gain in young horses. This study evaluated the relationship between age, gender, wither height (HT), BCS, and body weight (BW) in a large group of yearlings raised in central Kentucky over a 17-year period (2002–2018). Measurements were taken from colts (n = 2,048) and fillies (n = 2,032) during August of their yearling year. BCS was scored in 0.5 increments. Differences in measurements between genders were determined using an unpaired t-test. Colts (age 515.1 ± 34.7 d, BW 461.7 ± 34.7 kg, HT 155.3 ± 3.5 cm, BCS 5.88 ± 0.34; mean ± SD) and fillies (age 516.6± 34.0 d, BW 446.8 ± 32.4 kg, HT 153.7 ± 3.4 cm, BCS 5.94 ± 0.34; mean ± SD) were not different in age, but colts were heavier (P < 0.01) and taller (P < 0.01). Fillies had a higher BCS (P < 0.01). Over 95% of the yearlings had BCS of 5.5 to 6.5 with > 60% having a BCS of 6.0. Within each gender, multiple linear regression analysis using age, year of birth, HT, and BCS as independent variables and BW as the dependent variable resulted in regression coefficients for BCS of 15.1 ± 1.5 kg and 20.1 ± 1.4 kg (±SE) for colts and fillies, respectively. This suggests that weight gains from 15 to 20 kg will increase the body condition score of 450-kg yearlings from 5.5 to 6.5. The majority (>80%) of the yearlings measured in this study were being prepped for yearling sales where BCS of 6.0 is considered ideal. An understanding of how much BW gain is needed to affect BCS should be useful in the sales-prepping process.

Lipid Extraction and Sample Preservation Techniques for Stable Isotope Analysis and Ecological Assays.

Lipid extraction is an important component of many ecological and ecotoxicological measurements. For instance, percent lipid is often used as a measure of body condition, under the assumption that those individuals with higher lipid reserves are healthier. Likewise, lipids are depleted in 13C compared with protein, and it is consequently a routine to remove lipids prior to measuring carbon isotopes in ecological studies so that variation in lipid content does not obscure variation in diet. We provide detailed methods for two different protocols for lipid extraction: Soxhlet apparatus and manual distillation. We also provide methods for polar and non-polar solvents. Neutral (non-polar) solvents remove some lipids but few non-lipid compounds whereas polar solvents remove not only most lipids but also many non-lipid compounds. We discuss each of the methods and provide guidelines for best practices. We recommend that for stable isotope analysis, researchers test for a relationship between the change in the carbon stable isotope ratio and the amount of lipid extracted to see if the degree of extraction has an impact on isotope ratios. Stable isotope analysis is widely used by ecologists, and we provide a detailed methodology that minimizes known biases.

Relationships between environmental stressors and Cliff Swallow (Petrochelidon pyrrhonota) feather coloration and colony size

Cliff Swallows (Petrochelidon pyrrhonota) are aerial insectivores that experience mortality from vehicle collisions because they often nest and hunt under bridges and road culverts. Individual traits that may convey social information, such as body condition, or feather reflectance, may be associated with better coping around cars and other environmental stressors. Cliff swallow colony size may also be affected by environmental stressors. Our objective is to determine if proximity to roads and water level near the colony were related to wing length, body condition, colony size, and feather coloration in Cliff Swallows. We will do this by taking feather samples and measuring reflectance, and taking other body condition measurements, in addition to measuring colonies’ proximity to roads and level of water near the colonies’ locations.

Veterinary aid clinic assessments of working ponies in West Nusa Tenggara province, Indonesia: A retrospective study

Working ponies in the West Nusa Tenggara (NTB) province of Indonesia are relied upon as the principal mode of transport. They have important cultural, logistical and One Health significance for the local community. Given the tropical climate, these ponies face well recognised health and welfare challenges. Parameters relating to the general health and welfare of the ponies were assessed following data analysis of clinical records from three veterinary clinics held in 2018 and 2019. Records relating to 454 clinical examinations of ponies (n=365 stallions) aged between 1 to 25 years (mean 7.59 ± 4.70) were analysed. The mean body condition score (1 to 5 scoring system) across all clinics was 2.89 (±0.49; range 1.5, 4.5), with no significant difference between clinics (P= 0.297). The majority of ponies (84.57%; 95% CI 80.50, 87.92; 307/363) assessed presented with tachypnoea, 37.24% presented with tachycardia (95% CI 32.78, 41.92; 159/427), 14.80% (95% CI 11.10, 19.46; 41/277) recorded rectal temperatures considered hyperthermic (>38.5°C), and 38.0% did not show obvious evidence of sweating (95% CI 32.21, 44.16; 95/250). Ponies examined at the April/May 2019 clinic were more likely to be considered hyperthermic (P=0.009) and/or presented with tachycardia (P<0.001), whereas ponies examined in the November 2019 clinic were more likely to present with tachypnoea (P=0.001). In general, the objective measures of body condition and health indices of these ponies were considered adequate. Some abnormalities relating to prolonged recovery following exercise whilst working were considered likely related to thermoregulatory stress. Parasite burdens were found to be low, no haemoprotozoan parasites were detected and median faecal egg count was zero. Measures to encourage cooling and greater frequent rest periods continued surveillance and monitoring the health of these ponies will result in both enhanced welfare and advances in One Health initiatives.

An Environmentally Relevant Mixture of Perfluorooctanesulfonic Acid and Perfluorohexanesulfonic Acid Does Not Conform to Additivity in Northern Leopard Frogs Exposed Through Metamorphosis.

Per- and polyfluoroalkyl substances (PFAS) are chemicals associated with adverse health effects. At aqueous film-forming foam sites, they occur as mixtures, with perfluorooctanesulfonic acid (PFOS) and perfluorohexanesulfonic acid (PFHxS) commonly co-occurring in the highest concentrations. Although PFOS and PFHxS toxicities have been studied, few studies have tested their potential interaction. Using Rana pipiens, the present study compared toxicities of a 1:1 PFOS:PFHxS mixture to PFOS and PFHxS individually with the prediction that responses would be additive. Gosner stage 25 (GS 25) tadpoles were exposed through metamorphosis (GS 46) to 0.5 and 1 ppb PFOS or PFHxS alone or to a mixture of 0.5 ppb PFOS and 0.5 ppb PFHxS. Tadpoles were weighed and measured (snout-vent length [SVL]) at day 31, metamorphic climax (GS 42), and GS 46. These values were used to calculate the scaled mass index (SMI), a measure of body condition. Body burdens were quantified on day 31 and at GS 46. The PFOS and PFHxS body burdens were elevated relative to controls at GS 46. No effects were observed on survival, SVL, or mass. Single PFAS effects included a 17% reduction in SMI at day 31 (0.5 ppb PFHxS) and a 1.1-day longer metamorphic period (1 ppb PFHxS) relative to controls. Mixture results deviated from additivity-SMIs were higher than expected on day 31 and lower than expected at GS 42. In addition, time to GS 42 in the PFAS mixture exceeded expected additivity by 12 days. Results from a chronic exposure to a 1:1 PFOS:PFHxS mixture resulted in changes in body condition and length of metamorphosis that deviated from additivity. More PFAS mixture toxicity studies conducted at relevant ratios and concentrations are needed. Environ Toxicol Chem 2022;41:3007-3016. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Interactions of cranial helminths in the European polecat (Mustela putorius): Implications for host body condition

Multiple helminth species commonly co-occur within mammals and their interactions may negatively affect the survival and breeding success of their hosts. However, it has been difficult to prove competition or mutualism between co-infesting helminths in field studies of wild mammals. The sinus cavities of European polecats (Mustela putorius) can be parasitised by the trematode Troglotrema acutum and the nematode Skrjabingylus nasicola and both helminths can co-occur within hosts. While both parasites can damage the host's bone structure and cause severe pathologies, their impact on host body condition is unclear. It is also unknown whether both parasites interact and how this might affect cranial damage and host body condition. We examined 515 fresh polecat skulls for the presence of both helminths and measured the hosts' amount of kidney perirenal fat as a measure of body condition. Our results demonstrated that, in addition to a host-intrinsic fixed factor (sex) and random factors accounting for spatial and temporal stochasticity, the helminths influenced each other's presence. Infestation with T. acutum increased the probability of catching S. nasicola with increasing age of the host, while males already infested with S. nasicola were more likely to become infested with T. acutum than females infested with the nematode. While we speculate that both effects resulted from parasite-induced behavioural alterations (increased foot consumption), it is not clear why, in the latter case, this effect would be stronger in males than females. We showed that the abundances of both parasites had significant positive effect on the likely presence of skull damage and a significant negative effect on the predicted presence of kidney fat. Given the evolutionary arms race that both host-parasite systems have undergone, it appears unlikely that either helminth played a significant factor in the population decline of the polecat in Europe.

Long duration advertisement calls of nesting male plainfin midshipman fish are honest indicators of size and condition.

The plainfin midshipman fish (Porichthys notatus) has long served as a model organism for neuroethology research on acoustic communication and related social behaviors. Type I or 'singing' males produce highly stereotyped, periodic advertisement calls that are the longest known uninterrupted vertebrate vocalizations. Despite the extensive literature on the acoustic behaviour of this species, it remains unclear whether reproductive males signal their quality via their highly energetic, multiharmonic advertisement calls. Here, we recorded the advertisement calls of 22 reproductive type I males at night in a controlled laboratory setting in which males were housed in aquaria maintained at a constant temperature (13.9±0.3°C). The duration of the advertisement calls from type I males was observed to increase from the first call of the night to the middle call after which call duration remained steady until the early morning hours and first light. A strong positive correlation was observed between loudness (sound pressure level and maximum sound pressure level) of the advertisement call and body size (mass and standard length; rs>0.8). In addition, an asymptotic relationship was observed between the harmonic frequencies (f0-f10) of the advertisement calls and male body condition, with harmonic frequencies initially increasing with body condition indices, but then plateauing when body condition measures were high. Taken together, our results suggest that type I male advertisement calls provide reliable honest information about male quality regarding size and body condition. Such condition-dependent information of calling males could potentially be used by receptive females to help facilitate mate choice decisions.

Guided Classification Measurement of Body Condition in Beef Cows

Guided Classification Measurement of Body Condition in Beef Cows

Testing the parasite-mediated competition hypothesis between sympatric northern and southern flying squirrels.

Competition is a driving factor in shaping ecological communities and may act directly or indirectly through apparent competition. We examined a classic example of parasite-mediated competition between northern (Glaucomys sabrinus) and southern flying squirrels (G. volans) via the intestinal nematode, Strongyloides robustus, and tested whether it could act as a species barrier in a flying squirrel hybrid zone. We live-trapped flying squirrels (G. sabrinus and G. volans), grey squirrels (Sciurus carolinensis), red squirrels (Tamiasciurus hudsonicus), and chipmunks (Tamias striatus) from June–September 2019 at 30 woodlots in Ontario, Canada. Fecal samples from squirrels were collected and analyzed for the presence of endoparasite eggs. For each individual, we calculated Scaled Mass Index (SMI) as a measure of body condition to assess the effect of S. robustus on squirrels. We found eggs of S. robustus in all species except chipmunks. Infection with S. robustus did not appear to affect body condition of southern flying squirrels and grey squirrels, but we did find a weak negative effect on northern flying squirrels and red squirrels. Despite a weak asymmetric effect of S. robustus on flying squirrels, we did not find any evidence that parasite-mediated competition could lead to competitive exclusion from woodlots. Furthermore, S. robustus eggs were common in feces of the red squirrel, a species largely sympatric with northern flying squirrel.

Effects of Using Farm-Grown Forage as a Component in ad Libitum Liquid Feeding for Pregnant Sows in Group-Housing on Body Condition Development and Performance

When feeding pregnant sows, optimal body condition at birth is sought to avoid the effects of a deviant nutritional condition on health and performance. Various feeding concepts exist but mainly have a restriction in quantity and renunciation of farm-grown forage in common. An ad libitum liquid feeding system based on farm-grown forage in combination with a sow sorting gate (according to body weight—using mechanical scales) was realized on a commercial swine farm. The sorting gate coordinated access to two feeding areas with rations based on whole plant wheat-silage (WPWS) differing in energy content. In this study with a total of 183 pregnant sows, effects of restrictive dry feeding (System I) were compared with ad libitum liquid feeding based on farm-grown forage (System II). Sows were monitored regarding body condition development during pregnancy by measuring body condition score (BCS), body weight (BW), and back fat thickness (BFT) on different time points. Sow and piglet health (vaginal injuries of sows, rectal temperature during the peripartal period, vitality of newborn piglets) and performance data regarding litter characteristics were also recorded. Body condition development of the sows was absolutely comparable. Performance indicators and the course of birth were also similar but with significantly higher scores for piglet vitality in System II (p &lt; 0.05). The tested concept offers opportunities for more animal welfare and sustainability but remains to be further investigated regarding the repertoire of possibly applied farm-grown forage and the effects of the concept in the transit phase of sows.