Kidney Fat Index Research Articles

Demographic Risk Factors Vary in the Invasion Front of Chronic Wasting Disease in West Virginia, USA.

After detecting chronic wasting disease (CWD) in white-tailed deer (Odocoileus virginianus) in Hampshire County, West Virginia, USA, in 2005, we investigated the change of CWD apparent prevalence and potential factors influencing infection risk during the invasion front. Over eight sampling years (2006-2012 and 2017) during a 12-yr period within a 101-km2-area monitoring zone, we sampled and tested a total of 853 deer for CWD by ELISA and immunohistochemistry. Bayesian logistic regression of risk factors included collection year, age class, sex, and adjusted body weight (weight after accounting for sex, age, kidney fat index, and number of fetuses). In the whole-herd model (n=634), collection year, age, and adjusted body weight were associated with increased odds of CWD, whereas an age-weight interaction had a negative relationship. We found that males drove the positive associations with age and adjusted body weight, whereas females were responsible for the negative interaction effect. These findings suggest potential behavioral and physiological mechanisms related to sex that may influence CWD exposure. Older males exhibited higher CWD prevalence, aligning with previous studies. Notably, the novel finding of adjusted body weight as a risk factor in males warrants further investigation, and this study highlights the need for future research on social behavior and its role in CWD transmission within white-tailed deer populations.

Analysis of the individual condition of hares (Lepus europaeus Pall.) based on the body weight, KFI index, and pathological changes in selected internal organs

The study aimed to demonstrate the relationship between the presence of pathomorphological changes in the liver, heart, and kidneys of hares Lepus europaeus, and their individual condition expressed by body weight and the KFI index. The material for the study consisted of 70 hares harvested during two consecutive hunting seasons, 2021/2022 and 2022/2023, in two hunting districts in the western part of the Lublin Upland. Forty hares were examined in 2021/2022, and 30 were examined in 2022/2023. Pathomorphological changes were detected in 89% of the hares, and 14% of the hares with pathomorphological changes suffered from a parasitic invasion of the liver. In the group of hares with pathomorphological lesions, the poorest individual condition expressed by the body weight and kidney fat index (KFI) was found in individuals with a parasitic infection of the liver. This may indicate that parasites play a crucial role in the deterioration of the individual condition of hares and may have a negative impact on the survival and reproduction of the entire population.

SEASONAL AND HOST-ASSOCIATED VARIATION IN BOT FLY (OESTRIDAE: CUTEREBRINAE) PARASITISM OF LAGOMORPHS ACROSS AN ARID-LAND ECOSYSTEM IN SOUTHERN NEW MEXICO.

Bot flies (Oestridae: Cuterebrinae) are obligate mammalian parasites that complete the larval stage of their life cycle under the skin of their host. Most detailed studies of bot fly larval disease ecology have been conducted in temperate deciduous zone rodent systems. To understand the relative importance of seasonal and spatial factors, as well as factors intrinsic to the host, in underpinning the likelihood and extent of parasitism by bot flies in non-rodent hosts as well as in arid-land ecosystems, we examined the dynamic for black-tailed jackrabbit (Lepus californicus) and desert cottontail (Sylvilagus audubonii) parasitism by bot fly larvae (Cuterebra spp.) across 7 repeatedly sampled sites spread across approximately 500 km of the Chihuahuan Desert ecoregion of southern New Mexico. This environment is characterized by a climate that includes hot dry summers and cool to cold dry winters, as well as strongly seasonal summer monsoonal rains. Lagomorphs are a common mid-sized mammal in these landscapes. Bot fly parasitism was strongly seasonal, with peak prevalence and abundance in the spring, and there was spatial variation in the extent of parasitism between collection sites. Additionally, jackrabbits in better body condition were less likely to be parasitized (as indicated by kidney fat index). We did not find sex-based differences in bot fly parasitism between male and female jackrabbits. Thus, in arid-land ecoregions, abiotic factors are likely the primary driver of the bot fly-host interaction, whereas factors intrinsic to the host were of secondary importance for characterizing the interactions of bot flies and lagomorphs.

Low impact of tuberculosis severity on wild boar body condition

Body condition (BC), is a measure to assess the health status of domestic and wild animals. When food resources are abundant, a decrease in BC may indicate an increase in the energetic expenditure due to the effects of growth, reproduction, or disease. BC impoverishment is one of the most common clinical effects of diseases progressing chronically, such as animal tuberculosis (TB) caused by bacteria belonging to the Mycobacterium tuberculosis complex. The Eurasian wild boar (Sus scrofa) is the main wild TB reservoir in the Mediterranean basin. The specific aims of this work were to assess the relationship between sex, age and TB severity altogether on the BC of wild boar. For this purpose, we used the kidney fat index (KFI), to assess the impact of TB progression on the BC of 1372 hunter-harvested free-ranging wild boar in seven populations in southern Spain. Surprisingly, TB had only slight effects on wild boar BC and individuals exhibiting severe TB showed greater BC than TB-free individuals. The age (adults had greater BC than juveniles) and sex (females had greater BC than males) were the main BC determinants in wild boar. Sampling population and season explained more BC variability than individual factors, suggesting that other external factors might play an important role in the BC, and probably on the impact of the disease on this wild reservoir. The low impact of TB on wild boar BC suggests that individuals with severe TB and good BC represent potential long-term super-shedders of this pathogen.

Pearsonema plica in red foxes (Vulpes vulpes) from semi-arid areas of the Iberian Peninsula.

The nematode Pearsonema plica is a parasite infecting the urinary bladder of carnivores, with a described prevalence ranging from 1 to 90%. This parasite needs earthworms as intermediate host to complete its life cycle, being the red fox (Vulpes vulpes) a definitive host. The objective of this study was to analyse the prevalence and intensity of P. plica in the red fox population from the Region of Murcia (SE Spain), an area with semi-arid Mediterranean climate. The urinary bladder, kidneys and ureters of 167 red foxes were collected at necropsy, opened and observed to detect adult parasites. The influence of host variables (sex, age and body condition using Kidney Fat Index) and environmental variables (Normalized Difference Vegetation Index, Normalized Difference Moisture Index, Bare Soil Index, temperature, radiation, evapotranspiration, precipitation, Corine Land Cover categories and distance to urban areas) were evaluated using a Generalised Linear Model. Moran index was used to evaluate the parasite spatial aggregation. The prevalence found was very low (2.4%; median abundance 0 nematodes per fox; median intensity 7.5 nematodes per parasitized fox), which contrast with those described in other red fox populations in Europe. Environmental variables had a significant influence on the occurrence of P. plica, being NDMI, mean summer precipitation, percentage of forest and agricultural areas positively associated with P. plica abundance. The south-eastern Iberian Peninsula has a semi-arid climate that hinders the development of the life cycle of this nematode, which justifies its occurrence in specific areas where there are the suitable environmental conditions for the presence of earthworms. However, although semi-arid Mediterranean areas do not seem to be favourable carnivores to be parasitized by P. plica, we cannot underestimate the risk that exists in those areas where, either naturally or by human activity, there are environmental factors that favor the presence of this nematode.

Body condition of three autochthonous canid species from Serbia

The body condition of three autochthonous canid species in Serbia (wolf- Canis lupus, jackal-Canis aureus, and fox-Vulpes vulpes) was assessed based on the value of Kidney Fat Index (KFI). A total of 1232 specimens (147 wolves, 711 jackals, and 375 foxes) were collected during a ten years period. Data were analyzed according to multiple factors such as sex, age, seasons, species, and genus. The results indicate that the adult members of the Canis genus have a significantly better body conditional status than the yearlings as well as the representatives of the Vulpes genus (F (2, 900) = 71.465, p = 0.000). Significant differences in KFI across seasons are recorded in jackal (F (3, 542) = 6.912, p < 0.001) and fox (F (3, 371) = 2.675, p < 0.05) populations. Jackals have the highest KFI during winter when females are in significantly better body condition than males. None of these three canid species has shown a significant difference in body condition between sexes, although females had slightly higher KFI. Among adult female jackals, a difference in KFI between nursing ones and other adult and pregnant females is observed (H (2, n = 220) = 8.339, p = 0.016). Food deprivation which occurs naturally during the winter months does not affect the body conditional status of these predators which are well prepared for the upcoming breeding season. Considered as a whole, in spite of the differences observed at the genus level, the body condition status of these autochthonous canids measured through KFI index indicates decent average fitness status in wolves, jackals, and foxes in Serbia.

The use of radiography for measurements of the medullary cavity in the metacarpal bone in the European roe deer Capreolus capreolus for assessment of ontogenetic quality – preliminary study

&lt;b&gt;The objective was to verify the research hypothesis concerning a correlation between the surface area of the medullary bone and other fat indices and carcass weight. This study was also focused on identification of potential differences in the mean values of the fat parameters and carcass weight between the forest and field ecotypes of roe deer. The medullary cavity area was measured using the DIRA 200 program. Metacarpal bone III and the phalanges of the 2nd and 3rd fingers were measured as well. The investigations involved 38 females of the European roe deer Capreolus capreolus aged 3-5 years.The investigations revealed a negative statistically significant correlation between the surface area of the medullary cavity in metacarpal bone III and the kidney fat index KFI (rs = -0.483; p&lt;0.05) and the weight of the perirenal adipose tissue (rs = -0.362; p&lt;0.05). No correlation was shown between the area of the medullary cavity of metacarpal bone III and the doe carcass weight (rs = 0.093; ns). The size of the medullary cavity is an anatomical parameter that is not susceptible to cyclical changes in environmental conditions. As shown in this study, it is independent of the body weight and determines the amount of bone marrow and, hence, the amount of accumulated fat reserves. We believe that, besides biometric measurements, the surface area of the medullary cavity can be a good parameter for assessment of the ontogenetic quality of roe deer and for comparison of populations.

Ocena wybranych wskaźników kondycji osobniczej saren Capreolus capreolus poza sezonem łowieckim

The aim of the study was to assess the condition of roe deer in the closed hunting season based on the analysis of body weight and fat reserves in roe deer killed in road collisions. The research material consisted of kidneys dissected from 12 bucks, 4 does, and 5 fawns killed in road accidents between February 12 and May 10, 2020. The measurements were used for calculation of the kidney fat index (KFI) based on the formula [Bobek et al. 1984]: KFI = kidney weight with fat/kidney weight without fat. The study presents the distribution of the analyzed parameters with reference to the animal sex and month in which the animal died in the road collision. A distinct decline in the value of fat reserves expressed as the KFI index and the perirenal fat weight mass was observed in the study. In the first two months (February, March), this decrease coincided with reduced body weight, which rapidly increased in April. This may have been related to the intensive vegetation growth. Nevertheless, the costs of the breeding season (primarily in males) resulted in further weight loss in May. The analysis of carcass weight and fat reserves in roe deer killed in road collisions can complete the information about their individual condition and indirectly shows the condition of the roe deer population in the closed hunting season, i.e. in the critical period for this species (winter and the beginning of the breeding season).

Differential effects of ruminally protected amino acids on fattening of fallow deer in two culling periods

A well-balanced amino acid profile in the feedstuffs for livestock is essential to support adequate growth. This is well studied for monogastric species but still not well understood for ruminants and especially for the most unconventional species, like cervids. This study investigated the influence of ruminally protected lysine (Lys) and methionine (Met) supplementation during the fattening period, as well as two slaughter seasons (late autumn (LA) v. late winter (LW)), on the growth, carcass traits, body condition and blood plasma metabolites of fallow deer (Dama dama). Forty-five yearlings of fallow deer bucks were allocated into three groups, balanced by weight (40.2 ± 2.7 kg). The deer were pasture-fed and supplemented with barley, free-choice mineral premix, silage during the winter period, and varying levels of ruminally protected Lys and Met: no amino acids (Control), 9 g/day of Lys, and 9 g/day of Lys plus 3 g/day of Met (Lys+Met). Animals were slaughtered in two separate seasons, LA (six animals per group), and LW (nine animals per group). Animals culled in LA had higher average daily weight gain than LW (P = 0.002), due to the reduced growth during winter typical for seasonal cervids in temperate zone, mediated by the photoperiod. Dressing percentage was significantly higher in LW and in the Lys+Met group (P = 0.002). Body condition score (P = 0.024), kidney fat index (KFI) (P = 0.005), and internal fat (P < 0.001) increased significantly with Lys+Met supplementation. During LW, KFI (P = 0.004) and kidney fat (P = 0.001) were also significantly higher than in LA. Blood creatinine concentration increased significantly for deer receiving Lys (P = 0.002) and Lys+Met (P < 0.001). Also, triglycerides level increased in Lys group (P < 0.001). These findings highlight the effects of Lys and Met supplementation on the growth and internal fat storage for winter survival, suggesting a different use of the supplemented resource according to the season. Also, the observed effects on protein and fat metabolism of fallow deer may influence the production of farmed animals, and offer interesting insights about the physiology of the species.

Decline in body condition and high drought mortality limit the spread of wild chital deer in north-east Queensland, Australia

Chital deer (Axis axis) were introduced to the Burdekin district of northern Queensland, Australia in 1886. Compared with most successful ungulate introductions they have been slow to expand their distribution and increase in abundance (Moriarty 2004). In this study we consider the possibility that forage shortages caused by periodic droughts have caused sufficient mortalities to limit the increase and spread of chital in the region. The Burdekin district experiences fluctuations in forage according to seasonal rainfall as well as multi-year droughts. This study recorded the decline in body condition, measured as kidney fat index (KFI) and bone marrow fat (BMF), over the wet and dry seasons of two successive years in two chital deer populations during a period when annual rainfall was ~40% below average. We relate the falls in mean KFI from ~45–15%, and mean BMF from ~80–50% to the surveyed decline in chital populations of ~80%. The extent of the decline implies increased mortalities in all age classes as well as reduced reproductive output. We propose that it is likely that chital populations have experienced several such drought mortality events since the 1890s which have contributed to their limited spread.

Comparative analysis of body weight and condition in two brown hare populations

The condition of the populations are useful parameters for the reasonable game management. In this study the physical condition of Brown hare stocks (Lepus europaeus, Pallas 1785) was analyzed, measured body weight (BW) and determined kidney fat index (KFI). These methods were applied during our survey in the hunting period of 2014/15 and 2015/16. In total 272 (123 male and 149 female) samples were collected from two hunting areas in Great Plain (from County Békés and Jász-Nagykun Szolnok). The aim of our work was to collect data concerning the conditions of the populations. All hares was sexed and classified in 2 age groups (young &lt;1years), and (old&gt; 1years). The age was established by Stroh-mark in the hunting field and by dried eye lenses in the laboratory. BW and the weight of the kidney and perirenal fat was measured and the data were statistically analysed (group statistics, Levene’s test for Equality of Variances and, t-tests for Equality of Means). As a result of our examination the range of KFI was 1.25-5.14. The weight of perirenal fat was between 2-34gramm.KFI was greater in females than males. The average BW of the hares in every age groups were less than it is according to literature dates, however the conditions of the hares were good and in very good in both hunting areas. The BW and the amount of the perirenal fat in adult female hares were the greatest.

The cooler the better? Indirect effect of spring–summer temperature on fecundity in a capital breeder

AbstractFemale reproductive performance is a central component of ungulate population dynamics, and it can be influenced by individual, social, and environmental factors. Researchers have often assumed direct effects of different predictors on reproduction, yet more complex relationships should be considered when investigating temporal variations in life‐history traits within a broader eco‐evolutionary context. In this study, we explored direct effects of individual, social, and environmental predictors on female reproductive performance and investigated potential causal chains among variables. We analyzed the variation in fecundity, measured as the probability of being pregnant, in 215 adult female deer Cervus elaphus culled on the Italian Alps, with respect to age, body mass, kidney fat, jaw length, lactation status, population size, temperature and precipitation in spring–summer, temperature and snow depth in winter, and the delayed effect of spring–summer temperature. We used random forest and logistic regression models to select variables whose direct effects best explained variation in fecundity. Path analysis was used to test for alternative hypotheses of direct/indirect effects between pre‐selected weather (spring–summer temperature) and individual (age, kidney fat index [KFI]) predictors. The most important direct predictors of fecundity were age, kidney fat, and the interaction between kidney fat and spring–summer temperature. Path analysis supported the hypothesis that higher spring–summer temperature had negative, indirect effects on the probability of being pregnant, mediated by decreasing values of KFI. Our study revealed some complex, cause–effect relationships between weather stochasticity, body condition, and reproduction, possibly suggesting a conditional trade‐off between opportunity for reproduction and survival, and emphasizing how environmental variations and individual characteristics may interact to shape life‐history traits in ungulate populations.

Biometrical measurements as efficient indicators to assess wild boar body condition

Body condition (i.e., the amount of the energy stored in organs and tissues) is a key parameter that has been related with health, reproductive performance and density of wild ungulates including the wild boar (Sus scrofa). In this wild pig, a reference method to assess body condition has not yet been agreed and different procedures have been used in recent literature. The aim of this work was to generate an easy and reliable method based on biometrical measurements and with the ability to predict body fat in live or die boars. For this, a total of 207 hunted wild boar from three Spanish populations with contrasting food availability were included in this study. Sex, age, biometrical parameters (body weight, total length and chest girth) and body condition indicators (brisket and rump fat thickness, kidney fat index (KFI), ratio between chest girth-total length and scaled mass index) were assessed for each animal. A boosted regression trees (BRT) approach was carried out to find models based on age, sex and biometrical features that predicted brisket fat thickness in the studied animals. BRT models including sex, body weight, total length and chest girth as explanatory variables were able to predict brisket fat thickness in wild boar (68–73% of deviance explained). These models were not influenced by the location of sampling and their predictive values showed a good agreement with real brisket fat thickness (94.1–95.6). Predictive values obtained in BRT models from each area also agreed with food availability suggesting this is a valid indicator of body condition of wild boar in a broad range of environmental conditions.

Impact of environmental diversity of hunting complexes in the Lublin region on ontogenetic quality indicators in roe deer (Capreolus capreolus)

Populations of game are not confined to single ecosystems but function within higher-order units, e.g. ecological landscape. The basis for the establishment of the hunting complexes was the assumption that the existing game hunting grounds, i.e. the basic units implementing game management, are too small and do not cover the natural areas inhabited by game populations. Roe deer are flexible species and easily adapt to various site conditions, so they inhabit many different habitats, from large forest complexes, through small in-field tree stands and shrubs, to treeless grounds and field monocultures. The aim of the study was to determine a possible impact of environmental conditions prevailing in the hunting complexes of the Regional Directorate of State Forests (RDLP in Lublin) on the ontogenetic quality of roe deer. The study was conducted on 518 European roe deer (Capreolus capreolus) aged from 4 to 7 years (379 bucks and 139 does) harvested within hunting seasons 2010/2011–2013/2014. The results have shown that animals originating from areas with greater forest cover and denser stands are characterised by lower values of the mean ontogenetic quality parameters (carcase weight, kidney fat index, chest girth, weight of antlers) in comparison with animals from typical agricultural areas with fragmented forest complexes. These results indicate that, even in the case of such a eurytopic species as the roe deer, the ontogenetic quality differs between individual hunting complexes. The study has proved that strategies for hunting management of the roe deer should take into account the impact of the landscape structure, which provides a rationale behind creation of hunting complexes.

Fat reserve assessment in Pyrenean chamois using body measurements

Body condition is a measure of the energetic reserves stored in tissues and organs of animals in anticipation of periods of special energetic demands or to attenuate food shortages. For more than half a century, the kidney fat index (KFI) has been the most common invasive method for assessing body condition in ungulates. Since KFI requires animal necropsy, other non-invasive indicators based on body measurements have been suggested to assess body condition of mammals. These include the residuals from an ordinary least squares regression of body mass and linear measure of size (OLSr), the scores from a Principal Components Analysis on body measurements (PCAsc), and the scaled mass index (SMI). These indices, however, are often difficult to interpret and little effort has been made to confirm whether they are related to direct measures of fat reserves. We used the Bland-Altman method and linear models applied to biometric data to explore whether these three biometric indices can be used to assess body condition in 94 adult male and female Pyrenean chamois (Rupicapra pyrenaica pyrenaica). Animals were hunter-harvested in the Eastern Pyrenees (Spain) during two contrasting periods of food availability. We found that OLS residuals from the regression between body weight and hind foot length were the best proxy for fat reserves in both periods of the year. This simple, low cost and non-invasive biometric indicator can be used for monitoring body condition of chamois populations and probably in other ungulate species with similar life strategies.

Determining changes in the nutritional condition of red deer in Mediterranean ecosystems: Effects of environmental, management and demographic factors

Monitoring changes in the nutritional status of wild populations is crucial to understanding how species respond to natural or human-mediated variations in food availability and quality. It is a fundamental step for decision-making in wildlife management. Many studies on nutritional ecology still tend to rely on the use of single indicators. Nonetheless, nutrition has multiple interdependent facets that should be combined to better understand how organisms interact with their environment through feeding. Here, data from a large-scale cross-sectional survey conducted between 2010 and 2013 were used to examine the influence of environmental conditions and management practices on the variation of faecal nitrogen content (FN, index of dietary quality) and kidney fat index (KFI, indicator of nutritional condition) in red deer Cervus elaphus in the Mediterranean ecosystems of Iberia. Variations in the nutritional indicators in relation to sex, age, faecal fibre contents and faecal counts of lungworm larvae were also analysed. Our results showed that FN levels were statistically and positively correlated with vegetation primary productivity (P = 0.003). In contrast, faecal fibre fractions were significantly and negatively correlated with FN concentrations (P = 0.024 for hemicellulose, P < 0.0001 for cellulose and lignin). Moreover, a negative, marginally significant relationship was found between FN and the average altitude of the study areas (P = 0.055). The KFI was statistically higher in females than in males (P < 0.0001) and increased with increasing FN levels (P = 0.01). Fat stores were also statistically and positively correlated with vegetation productivity (P = 0.001) and with the amount of supplementary food provided (P = 0.04). The effect of high-quality diets on deer kidney fat deposits was gradually lower as the population density increased (P = 0.02). This result was more marked in non-food-supplemented populations. Both FN and KFI were statistically higher during the winter in relation to the autumn (P < 0.0001 and P = 0.005, respectively). This study shows that FN can be used to monitor and predict changes in the dietary quality, and the KFI in the nutritional status, in red deer in Mediterranean environments, reliably. Since both indicators showed different sensitivity to intrinsic, ecological and management determinants, this research also highlights their value and complementary use when studying populations of large wild herbivores.

Pre-, postnatal growth and maternal condition in a free ranging fallow deer population

We studied prenatal and postnatal growth rates and maternal effects in fallow deer (Dama dama) populations in free-ranging habitats in the Carpathian Basin. Data in this five-year long study were collected from pregnant females from December to the end of the hunting season (February), from newborns (May-June) and from 4–12 months-old fawns (October-June) in southwestern Hungary (Lábod region). The aims were to analyze foetal growth rate, assess the interaction between prenatal growth and maternal condition, and to examine factors influencing birth mass, and to measure fawn growth rates. During the study period foetal body mass (BM), body length (BL) and head length (HL) showed sigmoid growth. Correlations (rP) among the three features (BM, BL and HL) ranged from 0.78 to 0.93. Foetal BM was a quadratic function of foetal BL in both sexes. Foetal BM was linearly and negatively related to maternal kidney-fat-index (KFI) and body mass. Average birth mass was greater in males (4.66 kg) than females (4.31 kg), and it was greater in the middle of the fawning season (in the middle of June) than in the beginning (in May). The BM and the KFI of the fawns decreased at the end of the winter (February, eight months of age) but increased thereafter. The growth analysis of fawns generally showed that males compared with the females were heavier and larger; however it was not manifested clearly in all cases.

Effects of density, season, and food intake on sika deer nutrition on Yakushima Island, Japan

AbstractSika deer (Cervus nippon) suffer severe winter food limitation in northern Japan; however, plant food resources are available during winter in southern Japan and, consequently, deer nutritional status may not decrease there. To test this hypothesis, we measured seasonal changes in Riney's kidney fat index (RKFI) and stomach intake in 74 culled deer individuals from five areas with different deer densities on Yakushima Island, Japan. The average RKFI differed significantly among populations and ranged from 22.91 ± 11.91 to 76.23 ± 15.99. There was no significant correlation between RKFI and deer density. The total fresh weight of rumen contents also differed significantly among populations, ranging from 0.51 to 3.51 kg. Food intake and RKFI exhibited an L‐shaped distribution in the vicinity of a town ranch. However, we found that food intake had a significantly positive effect in populations at the other four locations, suggesting that changes in nutritional status were related to the quantity of deer rumen contents. Neither deer density nor season were significantly correlated with RKFI values. The average RKFI values exceeded 20 in all five locations. These findings indicate that the deer were not in a poor nutritional condition even in high density areas of &gt;70 head/km2, which supports the above hypothesis. Notably, food intake varied among individuals in the same area, but was independent of body weight and age, which suggests that food selectivity differs between deer individuals.

Does Kidney Fat Index Determine Body Condition of the Common Hippopotamus (Hippopotamus amphibius) in Luangwa River, Zambia?

The body condition of common hippopotamus (Hippopotamus amphibius) in Luangwa River, eastern Zambia was assessed using Kidney Fat Index. Thirty-two (32) hippopotamus carcasses from culled specimens were picked at random to assess body condition. Using a sharp knife, kidneys were extracted from the lumen of each of the 32 hippopotamus carcasses. The whole kidney with surrounding fat was weighed in grammes using a solar powered digital weighing scale. The fat deposited immediately around the kidney (ignoring the fat extending anteriorly and posteriorly in the kidney mesentery), was removed and re-weighed. Kidney Fat Index index of 40 percent was obtained suggesting poor body condition rating of 40.91 percent Left kidneys had 40.20 percent and the right kidneys 41.63 percent Kidney Fat Index varied significantly between seasons (i£ 2 = 55.99, DF= 8, ii= 0.05, P < 0.001), being higher during the first half of the year January - June when pasture was in good condition and lower in the last half of the year July - December, when grass was of poor quality. Quality of pasture per season determined body condition of hippopotamus. More research is required to establish hippopotamus body condition classes during years of good rains and drought.

On the population biology of Sarcoptes scabiei infesting Iberian ibex (Capra pyrenaica)

ABSTRACTIn this study, we analysed the Sarcoptes scabiei infrapopulations of 315 Iberian ibex (Capra pyrenaica) by means of skin digestion and differential mite counts. Mean density reached 178.2 mites/cm2 (range: 0.71–4514.29). Although the most frequently affected zones were hosts’ extremities and withers, higher mite densities were obtained from lips and extremities, suggesting that indirect infection through the substrate could also play a role in the disease epidemiology, together with direct transmission. The sex ratio of mites was female-biased (mean: 5.18 ♀♀/♂, range: 0.5–17). Larvae were more frequently found (nearly 50% of specimens) than nymphs, adult females or adult males. Mite density varied significantly between years and decreased with host age. Most of the variance was explained by the year, host sex, weight and kidney fat index (KFI). Taking into account the catabolic nature of the disease, our results suggest that hosts in good body condition could evidence a certain degree of resistance to the disease, which presumably has a genetic basis.