High red deer density depresses body mass of roe deer fawns

Many previous studies have pointed out that, when resources are limited, the potential for competition should be high among sympatric species that display overlaps in habitat and nutritional niches. However, reliable evidence of competition between red deer (Cervus elaphus) and roe deer (Capreolus capreolus) has not been yet reported for life history traits directly measuring performance such as body mass, reproduction, or survival. From long-term monitoring of deer populations in the reserve of La Petite Pierre (France), we measured the sex-specific responses of roe deer fawn body mass to changes in red deer density after accounting for possible confounding effects of date of shooting, climatic conditions, and roe deer density. As expected under the hypothesis of competition, red deer density in a given year had a marked negative influence on body mass of roe deer fawns born the same year and the following year. Fawn mass of roe deer males and females responded in similar ways to changes in red deer density. Our study provides the first evidence of a negative response of roe deer performance to high red deer density.     

Elaeophorosis in Barbary sheep and mule deer from the Texas Panhandle

Adult Elaeophora schneideri were recovered from the common carotid artery and its branches in 14 of 14 mule deer, Odocoileus hemionus, and 3 of 9 Barbary sheep or aoudads, Ammotragus lervia, from Palo Duro Canyon in the Texas Panhandle. Gross cutaneous lesions attributable to elaeophorosis in the Barbary sheep varied from small circumscribed scars up to 10 cm in diameter usually on the poll or orbital region to extensive proliferative irregular encrustations on the frontal, temporal and orbital regions, sometimes extending to the ears and muzzle. Individual lesions varied from slate-gray scarred areas to brown proliferative edematous and hyperemic encrustations, sometimes with depigmented pustules a few millimeters in diameter. Microscopic lesions ranged from granulation tissue to severe pyogranulomatous reactions with neutrophils, eosinophils, lymphocytes and plasma cells as the primary infiltration. Foreign body giant cells and/or microfilariae were not observed. Microscopic changes in the carotid arteries and their branches were limited to small villous projections on the intimal surface apparently resulting from medial hyperplasia. Cutaneous lesions attributable to elaeophorosis were not observed in mule deer. Histopathologic lesions in the carotid arteries of mule deer were similar to those observed in Barbary sheep. The comparative pathology of elaeophorosis in various hosts is reviewed and discussed in terms of its pathology in Barbary sheep. The potential ramifications of this infection on the expanding aoudad population in the southwestern United States require that elaeophorosis be considered in the management of this species, particularly in areas with sympatric mule deer populations.     

Lipogenic capacity and relative contribution of the different tissues and organs to lipid synthesis in male rat

The rates of 3H2O incorporation into total lipids and fatty acids were measured in vivo in the different organs and tissues of 7-week old male Wistar rats to compare the lipogenic capacity of those organs and tissues and to determine their relative contributions to body lipid synthesis. Our results were the following; (1) liver was the major site of the synthesis of total lipids and fatty acids (37 and 42%, respectively, of body synthesis); (2) white adipose tissues synthesized about 24% of the total lipids; mesenteric adipose tissue alone synthesizing 40% of the fatty acids produced in dissectable white adipose tissues; (3) skin showed low lipid synthesis but played an appreciable role in that synthesis (8% of the total) due to its large contribution to total body weight; (4) other organs (excluding liver) showed low lipid synthesis; however, that of the small intestine was 1-2% of body synthesis; (5) the rest of the carcass (mainly musculature and skeleton) contributed 25% to body lipid synthesis. The putative roles of the different tissues and organs in adipose tissue development have been discussed.     

Bacteria and nematodes in the conjunctiva of mule deer from Wyoming and Utah

Swabs of conjunctiva were collected from 44 live and 226 hunter-harvested mule deer (Odocoileus hemionus) from Wyoming and Utah (USA). We identified 29 gram negative and 22 gram positive bacterial taxonomic categories, but many isolates from hunter-harvested animals were environmental contaminants. Staphylococcus spp. and Micrococcus spp. were the most common gram positive bacteria isolated, and Enterobacter spp., Escherichia coli, and Pseudomonas spp. were common gram negative bacteria isolated. Thelazia californiensis were found in 15% of hunter-harvested deer in Utah in 1994 and in 8% in 1995. Nematodes were found in 40% of live deer in 1995 and 66% in 1996. Three live animals showed clinical signs of infectious keratoconjunctivitis (IKC) in 1996, but pathogenic bacteria were not isolated from these individuals. Hemolytic, non-piliated Moraxella ovis was isolated from two clinically normal live deer in 1996 and isolates were similar to those cultured from IKC cases from Wyoming and Utah.     

A serologic survey of mule deer and elk in Utah.

Sera from mule deer (Odocoileus hemionus) and elk (Cervus canadensis) in central and northern Utah were tested for the prevalence of antibodies to 11 diseases communicable to man or domestic livestock. Antibodies to Francisella tularensis (at 1:20) were found in 47 of 88 (53.4%) elk and 1 of 89 (1.1%) deer. A screening slide agglutination test for titers to Brucella (at 1:20) showed two reactors in elk but none in deer sera. No positive antibody titers were obtained in tests for anaplasmosis, Colorado tick fever, Rocky Mountain spotted fever, Q-fever, psittacosis, Powassan, western equine encephalitis, St. Louis encephalitis and California encephalitis.     

Blood and urinary profiles of free-ranging desert mule deer in Arizona

As a corollary to a more comprehensive study on their ecology, we documented blood and urinary profiles for 10 free-ranging desert mule deer (Odocoileus hemionus crooki) (five males, five females) captured by net-gun shot from a helicopter during February 1988 in Saguaro National Monument, Arizona. Pursuit with the helicopter for netting deer ranged from 3 to 15 min. Blood profiles included seven hematological characteristics and 12 serum chemistries, electrolytes, hormones and enzymes. Urine samples were assayed for urea nitrogen, creatinine, sodium, potassium, calcium and phosphorus. Urinary data were compared as ratios to creatinine. Serum cholesterol was greater (P less than 0.05) in males than females. Pursuit time was correlated with serum non-esterified fatty acids (r = 0.67, P less than 0.05) and influenced urinary specific gravity (r2 = 0.77, P less than 0.004), urea nitrogen: creatinine (r2 = 0.79, P less than 0.005), and potassium: creatinine (r2 = 0.42, P = 0.08) ratios. Increasing specific gravity was related to urinary creatinine concentration (r2 = 0.72, P less than 0.008). All deer exhibited acute adrenal stimulation, accompanied by elevated serum creatine phosphokinase and urinary potassium: creatinine ratios, which were indicative of acute excitement and muscle trauma associated with the capture process. We demonstrated that urinary data are a valuable supplement to serum data in demonstrating effects of intense physical exertion, and both forms of data emphasize the need to assess capture-related excitability as a source of variation in blood and urine characteristics of free-ranging desert mule deer.     

Epidemiology of chronic wasting disease in captive white-tailed and mule deer

The natural occurrence of chronic wasting disease (CWD) in a 1993 cohort of captive white-tailed deer (Odocoileus virginianus) afforded the opportunity to describe epidemic dynamics in this species and to compare dynamics with those seen in contemporary cohorts of captive mule deer (O. hemionus) also infected with CWD. The overall incidence of clinical CWD in white-tailed deer was 82% (nine of 11) among individuals that survived >15 mo. Affected white-tailed deer died or were killed because of terminal CWD at age 49-76 mo (x = 59.6 mo, SE = 3.9 mo). Epidemic dynamics of CWD in captive white-tailed deer were similar to dynamics in mule deer cohorts. Incidence of clinical CWD was 57% (4/7) among hand-raised (HR) and 67% (4/6) among dam-raised (DR) mule deer; affected HR mule deer succumbed at 64-86 mo of age (x = 72 mo; SE = 5 mo), and affected DR mule deer died at age 31-58 mo (x = 41.3 mo; SE = 6.1 mo). Sustained horizontal transmission of CWD most plausibly explained epidemic dynamics, but the original source of exposures could not be determined. Apparent differences in mean age at CWD-caused death among these cohorts may be attributable to differences in the timing or intensity of exposure to CWD, and these factors appear to be more likely to influence epidemic dynamics than species differences. It follows that CWD epidemic dynamics in sympatric, free-ranging white-tailed and mule deer sharing habitats in western North American ranges also may be similar.