Cervus Timorensis Russa Research Articles

An assessment of Zoonotic and Production Limiting Pathogens in Rusa Deer (Cervus timorensis rusa) from Mauritius

A population of approximately 70,000 rusa deer (Cervus timorensis russa) represents the most important mammal species reared for food on the island of Mauritius, being the main source of red meat for the local population. However, very limited information is available on the circulation of pathogens affecting the productivity and health of this species. To produce baseline data on the circulation of infectious pathogens in rusa deer under production, a serological survey and/or direct pathogen detection for six selected infectious diseases was undertaken in 2007 in a sample of 53% of the herds reared in semi-free-ranging conditions in hunting estates. Seropositive results were recorded for Johne's disease with an indirect ELISA test (1.7%, n = 351), heartwater with an immunofluorescence antibody test (IFAT) (95.5%, n = 178) and leptospirosis with a Microscopic Agglutination Test (MAT) (25.9%, n = 363). Significant associations were found between seroprevalence to some of the leptospiral serogroups detected (Tarassovi, Pomona, Sejroe and Mini) and age of the animals, animal density or location of the estates (being more prevalent in hotter and more humid areas). In addition, Mycobacterium bovis and M. avium subspecies paratuberculosis were confirmed in two deer carcasses by culture and PCR, respectively. No antibodies against Brucella spp. nor Rift Valley Fever virus were detected with the use of respective indirect ELISA's. The results obtained suggest that the population of rusa deer from Mauritius is exposed to a wide range of pathogens which may affect their productivity. In addition, the results highlight the potential public health risks incurred by deer industry workers and consumers. This survey fills an important gap in knowledge regarding the health of tropical deer meat in Mauritius and justifies the need to implement more regular surveys of selected pathogens in the deer population.

Epidemiological study of animal leptospirosis in new caledonia.

Leptospirosis is an important zoonotic disease in the world and a real public health concern for many years in New Caledonia. A cross-sectional survey was carried out on domestic and wild animals from New Caledonia in April 2009. Blood samples were collected from 30 cattle, 29 deers, (Cervus timorensis russa), 25 horses, 51 dogs, and 8 cats and were tested for 23 serovars of pathogenic Leptospira species by the microscopic agglutination test. From the total number of 143 samples, 84 (58.7%) were found to be positive towards one or several serovars of pathogenic leptospires. According to the species, the positive sera were obtained from 43% of 30 cattle, 72% of 29 Rusa deer, 80% of 25 horses, and 43% of 51 dogs, and fromall of the 8 cats tested. This study shows the broad dispersion and the high prevalence of the different serogroups of pathogenic Leptospira species tested, particularly among deer and horses. The disease is endemic in domestic animals and concerns all the species.

Toxoplasma gondiiin wild and domestic animals from New Caledonia

Samples (serum or meat juice) collected from 205 animals in New Caledonia in April 2009 were tested for antibodies against Toxoplasma gondii by ELISA using the multi-species ID Screen® Toxoplasmosis Indirect kit (IDVET, Montpellier). Antibodies to T. gondii were detected in 2% (1/49) of the pigs, in 3.3% (1/30) of the cattle, in 13.8% (4/29) of Rusa deers, in 16% (4/25) of the horses, in 32.8% (21/64) of the dogs, and in 50% (4/8) of cats. Statistically, no significant difference was observed between T. gondii seroprevalence and age or sex. No survey on the prevalence of T. gondii in animals has ever been conducted in New Caledonia and this is the first serological evidence of T. gondii in Rusa deer (Cervus timorensis russa). These results indicate an important circulation of T. gondii exists in the animal populations of New Caledonia. In view of humans being exposed, it is advisable to insist on sanitary education and on respect for good hygienic and food practice.

Bartonellae in animals and vectors in New Caledonia

Bartonellae are gram-negative facultative intracellular alpha-proteobacteria from the family Bartonellaceae. The natural history of bartonellae consists of a reservoir/host, which is a vertebrate with chronic intravascular infection with sustained bacteremia, and a vector (usually an arthropod) that transfers the bacteria from the reservoir to a susceptible yet uninfected host. In order to reveal the sources and reservoirs of Bartonella infection in animals and vectors in New Caledonia, we collected the blood samples of 64 dogs, 8 cats, 30 bovines, 25 horses and 29 wild deer Cervus timorensis russa and 308 associated blood-sucking parasites (14 keds Hippobosca equina, 258 ticks (22 Rhipicephalus microplus, 235 Rhipicephalus sanguineus, and 1 Haemaphysalis longicornis), 12 fleas Ctenocephalides felis and 24 dog lice Trichodectes canis). We isolated ten strains of Bartonella: four Bartonella henselae from cats and six Bartonella chomelii from cattle. The strains were characterized by sequencing of five genes (16S, ITS, rpoB, gltA and ftsZ). The six strains isolated from cattle were close to the reference strain of B. chomelii and were, probably, imported from France with cattle of Limousin race. PCR showed that 35% of keds collected from deer and 31% of deer were infected by B. aff. schoenbuchensis; all other samples were negative. Our data confirmed that in New Caledonia, as in other regions of the world, cats are the major reservoirs of B. henselae. We also confirmed that Hippoboscidae flies may serve as the vectors of ruminant-associated bartonellae.

Deciphering leptospirosis eco-epidemiology in New Caledonia

Leptospirosis is a zoonosis of worldwide distribution with major incidence in the tropics. In New Caledonia, it has been studied for years and is regarded as a major public health concern. It is characterized by an endemic pattern with seasonal epidemics arising during rainy periods, notably during “la Nina” periods. Both the endemic and epidemics have a rural epidemiology and result from the infection by a variety of Leptospira strains. The Institute Pasteur in New Caledonia (IPNC) is the reference laboratory for human leptospirosis and has been studying this disease for years, notably developing and implementing efficient molecular diagnostic tools. At the same time, an expertise on this disease has led to numerous studies on the epidemiology and physiopathology of leptospirosis. IPNC recently started a study aiming at identifying the Leptospira strains currently circulating in New Caledonia and their corresponding animal reservoirs. Because leptospirosis is a complex pathology involving reservoir hosts, environmental sources of infection and susceptible mammals including Man, the control of human leptospirosis has to take these animal reservoirs into account. In any region, a limited number of pathogenic Leptospira strains are circulating which can cause disease in humans. Every single Leptospira strain is supposed to be maintained by one or several reservoir animal host species. Current molecular methods allow identifying the infecting Leptospira strain at a sub-species level, possibly by directly using these molecular tools with DNA extracted from animal and human clinical specimens. We evaluated the usefulness of the sequence polymorphism of diagnostic PCR products and used this molecular tool for studying the prevalence and identification of the different Leptospira strains in both rodent and non-rodent Mammals. Because rodents are known to play a pivotal role in the maintenance of major Leptospira strains, an ecological study of rodent dynamics and their Leptospira prevalence is conducted in an area of highest incidence, taking seasonal and meteorological variability into account. Preliminary results confirm their role as reservoirs for L. interrogans Icterohaemorragiae and L. borgpetersenii Ballum and highlight a joint effect of temperature and pluviometry on rodents’ populations and their Leptospira carriage. Additionally, the introduced deer Cervus timorensis russa was shown to be a reservoir for L. borgpetersenii Hardjo.

Rapid Leptospira identification by direct sequencing of the diagnostic PCR products in New Caledonia

BackgroundMost of the current knowledge of leptospirosis epidemiology originates from serological results obtained with the reference Microscopic Agglutination Test (MAT). However, inconsistencies and weaknesses of this diagnostic technique are evident. A growing use of PCR has improved the early diagnosis of leptospirosis but a drawback is that it cannot provide information on the infecting Leptospira strain which provides important epidemiologic data. Our work is aimed at evaluating if the sequence polymorphism of diagnostic PCR products could be used to identify the infecting Leptospira strains in the New Caledonian environment.ResultsBoth the lfb1 and secY diagnostic PCR products displayed a sequence polymorphism that could prove useful in presumptively identifying the infecting leptospire. Using both this polymorphism and MLST results with New Caledonian isolates and clinical samples, we confirmed the epidemiological relevance of the sequence-based identification of Leptospira strains. Additionally, we identified one cluster of L. interrogans that contained no reference strain and one cluster of L. borgpetersenii found only in the introduced Rusa deer Cervus timorensis russa that is its probable reservoir.ConclusionsThe sequence polymorphism of diagnostic PCR products proved useful in presumptively identifying the infecting Leptospira strains. This could contribute to a better understanding of leptospirosis epidemiology by providing epidemiological information that cannot be directly attained from the use of PCR as an early diagnostic test for leptospirosis.

Population genetic structure of wild and farmed rusa deer (Cervus timorensis russa) in New-Caledonia inferred from polymorphic microsatellite loci

Historical records indicate that 12 rusa deer (Cervus timorensis russa) were introduced in New-Caledonia during the 1870s. We used eight polymorphic microsatellite DNA loci to assess the genetic differentiation and diversity of farmed and wild deer populations. Past genetic bottlenecks were detected in both sub-populations, although higher genetic diversity was maintained in farmed populations, probably due to the regular introduction of reproducers from wild populations and from other farms. The genetic structure of farmed and wild populations differed significantly. There was a significant isolation by distance for wild populations, whereas farmed populations were significantly differentiated between farms independently from their geographical proximity. Wild rusa deer consisted of small populations (with effective population sizes ranging between 7 and 19 individuals depending on the methods used), with a low parent-offspring dispersion range (0.20-2.02 km). Genetic tools and direct observations provided congruent estimates of dispersion and population sizes. We discuss the relevance of our results for management purposes.

Chemical composition, palatability and physical characteristics of venison from farmed deer

ABSTRACTThe quality of venison from farmed deer were evaluated based on chemical composition, palatability scores, W‐B shear force, ultimate pH, and color. The samples of venison were derived from javan rusa (Cervus timorensis russa), moluccan rusa (Cervus timorensis moluccensis), sambar (Cervus unicolor brookei), fallow (Dama dama) and imported red deer (Cervus elaphus). Moluccan rusa and red deer were fed grass. Javan rusa, sambar and fallow deer were fed concentrate. The venison obtained from grazing deer (grass‐fed) gave higher moisture content (75.3%) than concentrate‐fed or confinement‐raised deer (74.4%) and imported venison (70.62%). Fat content in venison shows some differences between muscles and species. The concentrate‐fed animals had a higher (P < 0.05) fat content in the venison than the grazing deer. Temperate deer (fallow and red deer) showed higher (P < 0.05) fat content than tropical deer (rusa and sambar deer). Venison obtained from concentrate‐fed deer showed normal ultimate pH values (pH ≤ 6.0) and more reddish in color than grass‐fed deer. The concentrate‐fed venison produced slightly higher (P > 0.05) palatability scores than grass‐fed venison. Feeding regimens (grass‐fed vs. concentrate‐fed) significantly (P < 0.05) influenced fat composition in the venison of farmed deer in this study.

L’élevage du cerf sur l’Ile de la Réunion voie de diversification d’une agriculture insulaire et enjeu de coopération régional

The rusa deer, Cervus timorensis russa, has become fully acclimatised to the subtropical conditions prevailing in La Réunion Island. Fourteen farms are referenced to date, breeding a stock of some 2,200 hinds. The first deer were introduced there during the seventeenth century from Indonesia, by European sailors who wanted to find fresh animal protein on their voyage to India. The first animal husbandry was nevertheless settled in the 1980s, with a view to utilise marginal land which could not be used by any other agricultural speculation. Deer are principally reared extensively, within a propitious sanitary environment, and animal productivity is good with an average of 0.7 weaned fawn per hind and per year. Local authorities have encouraged the development of smaller intensive farms to diversify animal productions on the island, but because of the high mortality rates in new-born fawns this kind of production appears to yield mediocre economic results. Rural development institutions are supporting venison producers in such areas as market organisation, pasture management, and pathological survey. On this multiethnic island, venison is consumed by all religious populations, contrary to porl and beef meat. The total demand for venison meat is estimated to exceed 100 tons per year: local production is about 30 tons, while imports, mainly from Europe and New Zealand, reach 50 tons. An increase in both animal productivity and the number of deer farmers could lead to an increase in the local venison production. Furthermore, the deer farming sector could be at the heart of such regional co-development programs as are strongly encouraged by the President of the Regional Council and as already initiated with nearby Maurititus in the field of pasture management.

Home range and habitat use of introduced rusa deer (Cervus timorensis russa) in a mosaic of savannah and native sclerophyll forest of New Caledonia

New Caledonia's unique flora evolved in the absence of ruminant herbivores until the 19th century. Native sclerophyll forests have been drastically reduced in extent, and browsing by introduced rusa deer is considered a major threat. We carried out a radio‐tracking study on wild rusa deer on a mosaic of savannahs and sclerophyll forest. The estimated mean home range size was 501 ±33 ha, with little seasonal variation. Deer showed a remarkable site fidelity (the average distance between the site of capture and the geographic centre of activity was 1042 ± 149 m). They used preferentially the sclerophyll forest and flood plains, especially during the dry season. These results confirm that rusa deer are likely to have a significant impact on the threatened sclerophyll forests, and they give some positive prospects for population control implemented locally.

Effect of drinking saline water on food and water intake, food digestibility, and nitrogen and mineral balances of rusa deer stags (Cervus timorensis russa)

AbstractThe salinity tolerance of Javan rusa deer (Cervus timorensis russa) was investigated with seven stags, aged 4·5 years. Animals were offered a medium-quality chaffed lucerne hay and given five different levels of water salinity: (a) control (570 mg/kg of total dissolved salts (TDS)) and (b) ‘saline’ water with TDS contents of 1000, 3500, 6000 and 8500 mg/kg. Food intake, food digestibility and nitrogen balance were not affected by increasing salt concentration in drinking water, however the drinking water (DW) intake, the total (food plus drinking) water intake and the DW:dry-matter ratio increased with increasing salt concentration. Some deer given water containing 8500 mg TDS per kg showed signs of stress which included large between-day fluctuations in water intake, opening of the orbital gland, head shaking, and rapid breathing. Rusa deer can tolerate drinking water containing 6000 mg TDS per kg for at least 9 days without harmful effect but may be unable to tolerate water with 8500 mg TDS per kg.

The diets of introduced rusa deer (Cervus timorensis russa) in a native sclerophyll forest and a native rainforest of New Caledonia

New Caledonia has an exceptionally diverse and unique flora, and there is growing concern about the impacts of introduced wild rusa deer on native forests. The diets of free‐ranging rusa deer from two native forest sites were studied using rumen content analysis. Samples (n = 61) from a sclerophyll forest site consisted principally of graminoids (64.6 ± 4.4% dry weight), mainly native grass, but the proportion of woody species increased during the dry season. In the rumen samples from the rainforest site (n = 56), woody species were the predominant plants (61.9 ± 3.7% dry weight), and the composition of the diet was more constant across seasons. Most of the food items found could not be identified to species level, but it is estimated that native plants represent 40–60% of rusa deer diet. Although more work is needed to assess diet preferences and impacts of rusa deer, we suggest that they represent a potentially important threat to some native plant species in New Caledonia.

Low levels of genetic variation within introduced Javan rusa deer (Cervus timorensis russa) in Australia

Javan rusa deer (Cervus timorensis russa) is one of six introduced wild deer species in Australia. The largest population is located in the Royal National Park (RNP), New South Wales, Australia. Although the deer are considered a pest in certain areas, they are also commercially valuable. Using molecular markers we aimed to characterise the level of genetic diversity within the RNP population and identify a possible genetic bottleneck associated with the introduction of seven founding individuals. We also aimed to identify appropriate polymorphic microsatellite loci that could assist in commercial breeding programmes and wild population management in Australia. The results indicate that Javan rusa deer from the RNP (n=37) had an average (±SE) of only 2.29±0.095 alleles/locus, which is substantially lower than that reported in source populations from New Caledonia (7.60±0.933 alleles/locus). These data combined with the presence of ‘genetic reduction signatures’ (P<0.001) indicate that this population has experienced a population bottleneck possibly at the time of establishment in Australia. Despite low allelic diversity, the large suite of identified polymorphic loci (n=24) shows promise for applications in population genetics, including parentage analysis (total parentage exclusion 0.944) within Australia. These data will contribute significantly to improving commercial breeding programmes and possibly to wild population management plans.

Consumption and Digestion of Forages by Male Rusa (Cervus timorensis russa) Deer-the Effects of Castration and Season

In a split-unit design, 12 Javan rusa (Cervus tinzorensis russa) stags (6 castrated and 6 entire) were used to investigate seasonal (winter, spring and summer) effects on intake, digestibility of food constituents, volatile fatty acid profile, and nitrogen retention, which given lucerne (Medicago sativa) or rhodes grass (Chloris guyana) hays. Entire stags ate 9% more dry matter (DM) than castrates (p<0.05). Both castrated and entire stags exhibited seasonal changes in DM intake, these being higher (p<0.05) in winter (62.3g/kg W0.75) than spring (56.9 g/kg W0.75) or summer (55.3 g/kg W0.75). Intakes of lucerne hay (211 g protein/kg DM) were significantly higher than of rhodes grass hay (49 g protein/kg DM) in all seasons (p<0.05). Digestibilities of DM (0.58), neutral detergent fibre (0.59) and acid detergent fibre (0.47) were similar between castrates and entires. DM digestibility was higher (p<0.0001) for lucerne (0.66) than rhodes grass (0.55), and was higher (p<0.05) in winter (0.60) than spring (0.58) or summer (0.57). The ruminal acetate concentrations were higher (p<0.001) in spring than summer (78 and 73 molar % respectively). Apparent digestibility of protein was significantly less (p<0.0001) for rhodes grass (0.37) than lucerne (0.75). N retention was positive for lucerne (15.2 g/d) but negative for rhodes grass (-2.8 g/d) (p<0.0001), and was higher (p<0.001) in summer (12.0 g/d) than spring (4.3 g/d) or winter (2.4 g/d). The tropical rusa deer exhibits seasonal variations in feed intake, food constituent digestibilities, VFA profile and N retention. Castration did not alter these traits. The results do not support the view that rusa deer can thrive on low-quality pastures. The productivity and commercial exploitation of rusa deer could be optimised if they are given high- protein feed during spring and summer.

Identification by R-banding and FISH of chromosome arms involved in Robertsonian translocations in several deer species.

We constructed and analyzed the RBG-banded karyotype of five deer species: Chital (Axis axis), White-lipped deer (Cervus albirostris), Rusa deer (Cervus timorensis russa), Sambar deer (Cervus unicolor) and Eld's deer (Cervus eldi siamensis). Among these five species, only Eld's deer had been previously karyotyped using R-banding. In order to identify all the chromosome correspondences with cattle and precisely which chromosome arms are involved in Robertsonian translocations, we compared the karyotypes of these five species with those of the closely related and well-characterized species, cattle (Bos taurus) and Vietnamese Sika deer (Cervus nippon pseudaxis). Among these six deer species (the five above plus the Vietnamese Sika deer), we found thirteen different Robertsonian translocations involving nineteen different chromosome arms. Thirteen chromosome arms were identified by comparison of R-banding patterns only and the remaining six were either confirmed or identified by FISH-mapping of bovine or caprine probes previously localized in cattle. Finally, we observed that five of the thirteen Robertsonian translocations are shared by at least two species and that some chromosome arms are more frequently involved in Robertsonian translocations than others.

A review of the diet of Rusa Deer Cervus timorensis russa in New Caledonia: Are the endemic plants defenceless against this introduced, eruptive ruminant?

Rusa Deer Cervus timorensis russa was introduced to New Caledonia in 1870 from Java, and has colonized the main island of Grande Terre, where it is found in virtually all the terrestrial biotopes. Despite its abundance and its socio-economic importance for New Caledonians, little is known about the diets of the wild deer populations living in contact with native vegetation which has a high degree of endemism and which, until recently, evolved without ruminant herbivores. We collected information on the diet of Rusa Deer in New Caledonia from published and unpublished reports, a questionnaire addressed to experts and preliminary data from browse-surveys. All sources of information suggested that wild Rusa Deer in New Caledonia is a mixed-feeder, and the list of plants consumed included 25 grasses, 15 forbs, 26 trees/shrubs and 12 vines and ferns. Nearly half (49%) of the plants identified as principal and preferred foods were introduced species. Physical defences (spines and thorns) did not seem to deter deer. It is remarkable that many of the avoided plants were native species (56% of the avoided species). Further research is required to confirm these results, but they are relevant to the evolution of plant/herbivore interactions and to the management of deer populations for conservation perspectives in island ecosystems.

Effect of the association of cattle and rusa deer (Cervus timorensis russa) on populations of cattle ticks (Boophilus microplus).

The wild population of rusa deer (Cervus timorensis russa) in New Caledonia (South Pacific) is nearly as large as the cattle population. The cattle tick is widespread and occurs all year round. Opinions are divided on the role of deer in the biological cycle of the tick: i) Do they maintain a sustainable tick population that is secondarily available for cattle? ii) Do they decrease the infestation of the environment by collecting larvae on the pasture, but preventing their development to the engorged female stage? or iii) Do they contribute to both situations? An experiment was conducted in three groups of pastures, each seeded with 450 000 larvae/ha and allowed to be grazed only by cattle, only by deer, and by a mixed herd of deer and cattle (deer representing 30% of the biomass), at approximately the same stocking rate (470-510 kg/ha). After 15 months of exposure, the tick burden per weight unit of host was 42 ticks/kg for the steers-only herd and 0.01/kg for the deer-only herd. The steers in the "mixed group" harbored 7 times fewer ticks (6.2/kg) than the cattle-only group, and the deer in the "mixed group," 130 times more (1.3/kg) than the deer-only group. Five emergency acaricide treatments had to be applied in the cattle-only group, but none in the other groups. The long-term sustainability of a viable tick population on deer as well as the potential benefit resulting from the association of deer and susceptible cattle in the tick control of cattle are highlighted.

Monoterpene effect on feeding choice by deer.

A previous study showed that Sitka black-tailed deer (Odocoileus hemionus sitkensis) consumption was negatively correlated with monoterpene content in western redcedar (Thuja plicata). To test whether these monoterpenes were deterrent to Sitka black-tailed deer, we performed feeding choice experiments with four hydrocarbon (sabinene, myrcene, alpha-pinene, and d + l-limonene) and one oxygenated (alpha,beta-thujone) monoterpene solution at their highest natural concentration in western redcedar foliage. To test whether deer response was species specific, we ran similar experiments on European roe deer (Capreolus capreolus) and rusa deer (Cervus timorensis russa). In all experiments, monoterpenes were repellent. Solutions with alpha,beta-thujone, the major monoterpene in redcedar leaves, were the most repellent of the solutions tested. We then analyzed how black-tailed and roe deer responded to (1) an increase in concentration of the monoterpenes with the weakest repellent effects (hydrocarbon monoterpenes) and (2) a decrease in concentration of the monoterpene with strongest effect (alpha,beta-thujone). Repellency tended to increase with concentration for hydrocarbon monoterpenes, but remained strong for alpha,beta-thujone. As wild deer regularly feed on plants containing monoterpenes, this raises the question as to how the animals deal with these molecules.

The Effect of Castration on Growth and Body Composition of Javan Rusa Stags

The effects of castration on growth and body composition of Javan rusa (Cervus timorensis russa) stags were examined at three slaughter ages in three experiments. Castration had no effects on growth rates, or liveweights at periodic weighings, at any stage in Experiments I and 2, when the stags were slaughtered at 19 and 13 months of age, respectively. In Experiment 3, monthly liveweights of castrated and entire stags were not significantly different until the stags were 21 months old. From this age, when they had recovered from their first rut season and were in their second spring/early summer, the entires grew more rapidly than the castrates. There were seasonal changes in growth in both treatments, indicating that pasture conditions influenced performance. Liveweights of entires and castrates were similar in stags slaughtered at 13 and 19 months, but castrates were smaller than entires at 25 months. Castration reduced the size of the head and skin, but there was little important effect of castration on body components at any slaughter age. Castration can be recommended as a management tool for rusa stags, especially if the animals are to be slaughtered before they exceed 19 months of age.

Primal joints and hind-leg cuts of entire and castrated Javan rusa ( Cervus timorensis russa) stags

The effects of castration on the primal joints and the cuts of the leg joint of Javan rusa ( Cervus timorensis russa) stag carcases was investigated at three slaughter ages (13, 19 and 25 months). Castration reduced the weights of some primal joints in the 19- and 25-months age groups, but not at 13 months. At 19 months, the neck, and neck plus chuck, were heavier by 35 and 17% respectively in entires ( P<0.05), and at 25 months entires had heavier carcases, shoulder, forequarter and hindquarter ( P<0.05). The leg and saddle joints were approximately 39 and 18% of the side, respectively, for both treatments and all ages. The proportions of the neck, and neck plus chuck, were higher ( P<0.05) in 19-month old entires than castrates. There were few significant differences between treatments in the weight or proportion of the hind leg cuts at any slaughter age, but in the 25-months group the silverside was 8% ( P<0.05) heavier in entires. In both castrates and entires, there appeared to be an increase in the percentage of the rump as the animals grew from 13 to 19 months of age.