Comparison of performance and carcass composition of a novel slow-growing crossbred broiler with fast-growing broiler for chicken meat in Australia.

Slow-growing broilers offer differentiation in the chicken meat market for consumers who have distinct preferences based on perceived higher welfare indices and willingness to pay a higher price for the product. Although breeding for slow-growing broilers is relatively advanced in Europe and the United States, it is limited in Australia. Crossbreeding is one of the approaches taken to developing slow-growing broiler strains. Thus, the aim of this study was to compare performance, immune response, leg health, carcass characteristics, and meat quality of a novel crossbred slow-growing broiler breed (SGB) with the conventional, fast-growing Cobb 500 broiler (CB) to assess their suitability as an alternative for chicken meat production in Australia. A total of 236 one-day-old broiler chicks (116 SGB and 120 fast-growing CB) were reared on standard commercial diet in an intensive production system. Birds and feed were weighed on a weekly basis and feed intake and feed conversion ratio calculated. At 21 d of age, a 2% suspension of sheep red blood cells was injected subcutaneously into 8 broilers of each breed to compare their antibody response. Birds from both breeds were grown to a final live weight of 2.0-2.2 kg, before a latency-to-lie (LTL) test, carcass analysis and apparent metabolizable energy (AME) assay were performed. The SGB reached the target weight at 55 d of age compared with 32 d in CB. However, SGB stood for longer during LTL, had higher thigh, drumstick, and wing yields (as a percentage of carcass weight) as well as darker and redder meat in comparison with the CB. The CB had better feed conversion efficiency, higher antibody (IgM) production, higher AME, heavier breast yield, and lower meat drip loss than the SGB. Although fast-growing CB outperformed the SGB for traditional performance parameters, the crossbred in this study was comparable with other slow-growing broiler breeds and strains across different countries and is thus a suitable candidate for a slow-growing alternative in Australia.

Changes to Cobb 500 chick characteristics, bone ash, and residual yolk mineral reserves during time spent in the hatcher.

Previous work has identified an effect of hatch time on chick femur mineralization. This experiment assessed the impact of hatch time and a 24-h post-hatch unfed time period on chick bone mineralization and yolk mineral utilization. In early hatching chicks, yolk Mg, Zn, K, P, Fe, and Cu decreased by 40 to 50% over the 24-h post-hatch unfed time period, whereas yolk Ca and Na decreased by 25 to 40% (P = 0.026). Yolk Sr was intermediate, decreasing by 37%. Late hatching chicks which had been hatched for no more than 30 h had a higher femur bone ash percentage compared to early hatching chicks which had spent over a 30-hour sojourn unfed in the incubator (P = 0.013). These results indicate that removing chicks from the incubator within 30 h of their hatch is likely to benefit their femoral mineralization.

Frequent range visits further from the shed relate positively to free-range broiler chicken welfare.

Little is known about the implications of accessing an outdoor range for broiler chicken welfare, particularly in relation to the distance ranged from the shed. Therefore, we monitored individual ranging behaviour of commercial free-range broiler chickens and identified relationships with welfare indicators. The individual ranging behaviour of 305 mixed-sex Ross 308 broiler chickens was tracked on a commercial farm from the second day of range access to slaughter age (from 16 to 42 days of age) by radio frequency identification (RFID) technology. The radio frequency identification antennas were placed at pop-holes and on the range at 2.7 and 11.2 m from the home shed to determine the total number of range visits and the distance ranged from the shed. Chickens were categorised into close-ranging (CR) or distant-ranging (DR) categories based on the frequency of visits less than or greater than 2.7 m from the home shed, respectively. Half of the tracked chickens (n=153) were weighed at 7 days of age, and from 14 days of age their body weight, foot pad dermatitis (FPD), hock burn (HB) and gait scores were assessed weekly. The remaining tracked chickens (n=152) were assessed for fear and stress responses before (12 days of age) and after range access was provided (45 days of age) by quantifying their plasma corticosterone response to capture and 12 min confinement in a transport crate followed by behavioural fear responses to a tonic immobility (TI) test. Distant-ranging chickens could be predicted based on lighter BW at 7 and 14 days of age (P=0.05), that is before range access was first provided. After range access was provided, DR chickens weighed less every week (P=0.001), had better gait scores (P=0.01) and reduced corticosterone response to handling and confinement (P<0.05) compared to CR chickens. Longer and more frequent range visits were correlated with the number of visits further from the shed (P<0.01); hence distant ranging was correlated with the amount of range access, and consequently the relationships between ranging frequency, duration and distance were strong. These relationships indicate that longer, more frequent and greater ranging from the home shed was associated with improved welfare. Further research is required to identify whether these relationships between ranging behaviour and welfare are causal.

Changes to mineral levels in the yolk of meat chicken embryos during incubation.

A total of 864 settable Cobb 500 eggs were used to explore changes in yolk mineral content during incubation. Eggs were individually weighed and then placed in a commercial incubator. On embryonic day (ED) 0, 6.5, 13.5, and 17.5, 36 eggs were sampled and yolk weight and mineral content were determined. The concentration of iron (Fe), phosphorus (P), and zinc (Zn) declined (P < 0.05) from ED0 to ED17.5. The concentration of calcium (Ca), magnesium (Mg), and strontium (Sr) increased (P < 0.05) from ED0 to ED17.5. The concentration of copper (Cu), potassium (K), and sodium (Na) increased initially (ED0 to ED6.5) but declined thereafter. There was no change (P > 0.05) in the concentration of yolk manganese (Mn) from ED0 to ED17.5. Substantial changes in yolk mineral concentration occur during incubation and are presumably associated with mobilization of shell reserves and flux between albumen and yolk. These data may be useful in designing in ovo interventions, optimizing meat chicken breeder premix formulation or assembly of suitable neonatal or pre-starter diets for meat chicken chicks.

The leg strength of two commercial strains of meat chicken subjected to different incubation profiles.

Lower egg shell temperatures (EST) during the first 2 weeks of incubation, notionally known as Slow start incubation, extended the standing time of a 5-week-old fast feathering meat chicken parent line. This study was designed to evaluate the effect of Slow start incubation on the standing ability of commercial meat chickens. Eggs from two strains of meat chickens, Strains 1 and 2, were incubated using either the Slow start incubation, (the initial EST was 36.75°C followed by a gradual increase in EST, reaching 37.8°C at day 16 of incubation), or Control incubation (EST 37.75°C to 38°C from the start of incubation until day 18 of incubation). Eggs were observed every 6 h from 468 h until 516 h of incubation to identify chick hatch window. At 516 h of incubation all chicks were taken out of the incubator (take-off). Chicks from each Strain and incubation treatment were randomly selected for assessment of chick weight, chick length, yolk sac weight, serum Ca and P, and femoral bone ash (BA). All unhatched eggs were inspected to determine the stage of embryo failure. Remaining chicks were grown for 5 weeks in floorpens. Weekly feed intake (FI), chick weight and feed conversion ratio (FCR) were determined. At 35 days of age the standing ability of visibly male birds was assessed in a latency-to-lie test. Compared to the Control, Slow start incubation delayed the average hatch time of both strains by ∼13 h, and reduced hatchability with 4.6% live but unhatched chicks, which was most evident in Strain 2. Significant differences due to main effects only were observed at take-off. Strain 1 chicks were significantly heavier and longer with higher serum Ca but significantly lower BA and serum P than Strain 2. Slow start incubation generated significantly heavier chicks that were shorter, but had significantly heavier yolk sacs, lower serum Ca but higher serum P than Control incubated chicks. During the 1st week post hatch Strain 1 Control incubated chicks had significantly higher FI and higher FCR than all other Strain and incubation treatments. At 35 days of age Slow start incubated birds of both Strains stood significantly longer than those from the Control incubation. This experiment clearly demonstrated the ability of Slow start incubation of commercial meat chickens to improve their leg strength.

Why did severe feather pecking and cannibalism outbreaks occur? An unintended case study while investigating the effects of forage and stress on pullets during rearing.

This 2 × 2 factorial experiment aimed to investigate the effects of stimulating foraging behavior from wk 6 and imposed stress at wk 16 on the development of severe feather pecking (SFP) in chickens reared for free-range egg production. Non-beak-trimmed ISA Brown chicks were purchased at one day old and floor-reared on wood shavings. From wk 6, straw was provided daily in dispensers (Forage vs. No forage) to stimulate foraging. At wk 15, there were 16 pens of 50 pullets. "Stressors" were applied to half the pens in wk 16 via combined transport, relocation, and mixing (TRM) of pullets, simulating activities around transfer from the rearing to egg-laying farm (TRM vs. Not TRM). Range access was permitted from wk 21. Behavior, plumage damage (PD), growth, egg production, feed use, injuries, and mortalities were recorded, along with litter moisture and pH. In wk 26, an SFP outbreak commenced. By wk 34, PD was worse in south- than north-aspect pens (P < 0.001). Further, PD was more affected by side of the shed than the experimental treatments. In wk 30, an outbreak of injurious pecking (IP) commenced in the 4 TRM-treatment pens on the south side, with IP deaths almost 3 times more common in the Forage+TRM than No forage+TRM treatment. We suggest factors associated with a 13-day rainfall event that occurred in late winter predisposed the flock to SFP. While multiple factors such as winter cold, muddy ranges, damp floor litter with elevated pH, among others coincided, hens were clearly more impacted in south- than north-aspect pens. Once initiated, SFP possibly spread via social learning, and by wk 40, ∼98% of hens had PD. Interestingly, the IP outbreak was related to a combination of factors (stressors?), such as being housed in colder, damper south-aspect pens (note: southern hemisphere), having added Forage, and TRM. These unexpected relationships could help direct future research to identify the specific factors involved in the causation of SFP and IP/cannibalism outbreaks.

Incubation and hatch management: consequences for bone mineralization in Cobb 500 meat chickens.

From ~35 days of age fast growing meat chickens spend extended periods sitting or lying and less time standing. In a fast-feathering parent line lower early incubation temperatures which delayed chick hatch time, improved bone ash and extended their standing time. This incubation study assessed the consequences of incubation temperatures, hatch time and chick management at hatch/take off on femoral bone ash (BA) in Cobb 500 meat chickens. Embryos were incubated under either Control (between 37.8°C and 38.2°C egg shell temperature (EST)) or a Slow start (from 37.2°C at sett (the start of incubation), reaching 37.8°C EST at day 13 incubation), temperatures. Hatched chicks were identified at 492 h (20.5 days of incubation - classified as early (E)) or, between >492 and ⩽516 h (>20.5 and ⩽21.5 days of incubation - classified as late (L)), from setting. The E hatch chicks were allocated across three post-hatch treatments; treatment 1: E hatch chicks that were sampled E at 492 h from setting; treatment 2: E hatch chicks that were fed for a further 24 h in a floorpen before being sampled L at 516 h from setting; treatment 3: E hatch chicks that spent a further 24 h in the incubator before being sampled L at 516 h from setting. All L hatch chicks formed one treatment group which was sampled L at 516 h (i.e. L hatch chicks sampled L). It is not possible to sample L hatching chicks E hence this treatment is absent from the experimental design. Slow start incubation resulted in a higher total hatch percentage with a greater proportion of chicks hatching L, compared with the Control incubation. The L hatching chicks had significantly higher BA than the E hatching chicks. Of the E hatching chicks, those sampled both E and L had significantly lower BA than E hatching chicks fed for 24 h before L sampling. The E hatch, fed and sampled L chicks had the numerically highest BA, which was not significantly different from the BA of the L hatching chicks sampled L These results demonstrate that BA at hatch can be improved, either by extending the incubation period through a Slow start incubation profile, inducing L hatch, or alternatively, via the prompt provision of feed to E hatching chicks.

Earlier hatching time predisposes Cobb broiler chickens to tibial dyschondroplasia.

Fertile eggs from Cobb 500 broiler breeder hens were incubated to provide low starting egg shell temperatures (EST; 36.9°C to 37.3°C) which were gradually increased to 37.8°C during the first 7 to 15 days of incubation compared with eggs incubated with a constant EST of 37.8°C (standard conditions) over the first 18 days of incubation. Time of individual chick hatching (measured at 6 h intervals from 468 h of incubation), chick weight, chick length and yolk weight were measured at take-off and BW was measured at 7, 14, 28, 34 and 42 days of age. Male birds at 34 and 42 days of age were assessed for their ability to remain standing in a latency-to-lie test. At 34 and 42 days, male birds were examined for leg symmetry, foot pad dermatitis, hock bruising and scored (scale 0 to 4, where 0=no lesion and 4=lesions extending completely across the tibial growth plate) for tibial dyschondroplasia (TD) lesions. The lower EST profiles caused chicks to hatch later than those incubated under the standard EST profile. Chicks which hatched at ⩽498 h incubation grew faster over the first 7 days than those that hatched later. There were significantly more birds (only males were studied) that hatched from the lower EST profiles with TD scores of 0 and 1 and fewer with score 4 at 34 days than those hatched under the standard profile. Male birds at 34 days with TD lesions ⩾3 stood for significantly shorter times than males with TD scores ⩽2. Moreover, male birds at 34 and 42 days with TD lesion scores of ⩾3 hatched significantly earlier and grew significantly faster over the first 2 weeks of age than did male birds with TD scores ⩽2. It appears possible to decrease the severity and prevalence of TD in the Cobb 500 broiler by ensuring that the birds do not hatch before 498 h of incubation.

Live and inactivated vaccine regimens against caecal Salmonella Typhimurium colonisation in laying hens.

OBJECTIVE: In Australia, Salmonella serovar Typhimurium (S. Typhimurium) is the predominant zoonotic serovar in humans and is frequently isolated from layer hens. Vaccination against this serovar has been previously shown to be effective in broilers and the aim of this current study was to assess and determine the best vaccination strategy (live or inactivated) to minimise caecal colonisation by S. Typhimurium. METHODS: A long-term experiment (56 weeks) was conducted on ISABROWN pullets using a commercial live aroA deleted mutant S. Typhimurium vaccine and an autogenous inactivated multivalent Salmonella vaccine (containing serovars Typhimurium, Infantis, Montevideo and Zanzibar). These vaccines were administered PO or by SC or IM injection, either alone or in combination. Pullets were vaccinated throughout rearing (to 18 weeks of age) and sequentially bled for antibody titre levels. The birds, vaccinated and controls, were challenged orally with a field isolate of S. Typhimurium at different ages, held for 21 days post-challenge, then euthanased and their caeca cultured for the presence of Salmonella. RESULTS: None of the oral live-vaccinated groups exhibited lasting protection. When administered twice, the inactivated vaccine gave significant protection at 17 weeks of age and the live vaccine given by SC injection given twice produced significant protection at 17, 25 and 34 weeks. CONCLUSIONS: Vaccination regimens that included parenteral administration of live or inactivated vaccines and thus achieved positive serum antibody levels were able to provide protection against challenge. Hence, vaccination may play a useful role in a management strategy for Salmonella carriage in layer flocks.

Pathotyping of Australian isolates of Marek's disease virus in commercial broiler chickens vaccinated with herpesvirus of turkeys (HVT) or bivalent (HVT/SB1) vaccine and association with viral load in the spleen and feather dander.

OBJECTIVE: To pathotype Australian isolates of Marek's disease virus (MDV) in commercial broiler chickens using standard methods and to evaluate early markers of pathotype. METHODS: A complete 3 × 4 factorial experiment with two replicates was conducted using 648 Cobb broiler chickens in 24 isolators. The experimental factors were vaccination (unvaccinated, herpesvirus of turkeys (HVT), bivalent (HVT + SB1 strain of serotype 2 MDV)) and MDV challenge (unchallenged or 500 plaque-forming units of isolates MFP57, 02LAR or FT158). Mortality, body weight, immune-organ weights and viral load were measured to 56 days post challenge (dpc). Vaccinal protective index (PI) and virulence rank (VR) were calculated based on gross Marek's disease (MD) pathology. RESULTS: The PIs provided by the HVT and bivalent vaccines against challenge with MPF57, 02LAR, and FT158 were 84.6% 56%, 61.4% and 82.2%, 60.8%, 57.7%, respectively, leading to putative pathotypes of virulent MDV for MPF57 and very virulent MDV for 02LAR and FT158. Significantly more of the unvaccinated chickens (85.7%) had MD lesions than chickens vaccinated with either the HVT (26.8%) or bivalent vaccine (27.6%). Strong linear relationships were observed between the incidence of MD at 56 dpc and MDV load in the spleen at 7 dpc (R(2) = 0.71) and MDV load in the isolator exhaust dust at 14 dpc (R(2) = 0.57) and 21 dpc (R(2) = 0.51). Immune organ weights had a weaker association with subsequent MD incidence. CONCLUSION: Pathotyping results in broiler chickens with maternal antibody broadly agreed with those in specific-pathogen-free chickens in other studies, with some important differences. MDV load in the spleen at 7 dpc and in isolator dust at both 14 and 21 dpc was a powerful early predictor of subsequent MD incidence.

Development of a chick bioassay for determination of infectivity of viral pathogens in poultry litter.

OBJECTIVE: To develop a chicken bioassay to detect infective viral pathogens in poultry litter and to determine the effects of type of chicken and age of exposure, as well as the effect of simulated litter transportation, on the level of viral infectivity detected. DESIGN: A 5 × 2 × 2 factorial design, plus negative controls. Five chicken litters, including two with deliberate contamination (one transported and one not), two chicken types (specific-pathogen-free (SPF) Leghorns and Cobb broilers) and two ages at initial exposure (days 1 and 8). Two replicates of each treatment combination. METHODS: The 10 chickens in each of 22 isolators were either exposed (20 isolators) or not (2 isolators) to 8 L of previously used or deliberately contaminated poultry litter in two deep scratch trays. At day 35 post-exposure, sera were assayed for antibodies against chicken anaemia virus (CAV), infectious bronchitis virus (IBV), infectious bursal disease virus (IBDV), Newcastle disease virus (NDV) and fowl adenovirus (FAV). Spleen samples were tested for Marek's disease virus (MDV) using real-time polymerase chain reaction. RESULTS: The bioassay detected CAV, IBDV and FAV, but not NDV, IBV or MDV, in chickens exposed to infected litters. Infection in SPF chickens was detected with greater sensitivity than in the broiler chickens. Sensitivity increased with age at exposure in broiler but not SPF chickens. Simulated transportation for 24 h had little effect on pathogen detection. CONCLUSION: A bioassay based on the exposure of day-old SPF chickens to poultry litter and measurement of seroconversion at day 35 post-exposure is a useful semi-quantitative assay for viral infectivity in poultry litter, with overnight transportation of litter having little effect on the level of viral infectivity detected. This bioassay has applications in research on litter treatment protocols.

A quantitative assessment of residual protein levels on dental instruments reprocessed by manual, ultrasonic and automated cleaning methods.

OBJECTIVE: To assess residual protein on dental instruments cleaned in general dental practice by manual, manual plus ultrasonic and automated washer disinfector (AWD) processes. DESIGN AND SETTING: Instruments submitted by 30 dental surgeries in the South West of England. SUBJECTS (MATERIALS) AND METHODS: Instruments analysed were matrix bands, associated retaining clips, diamond and stainless steel burs, extraction forceps and hand scalers. Each instrument was visually assessed under magnification for residual debris. Residual protein was extracted by immersion in detergent and sonication. A collection of used but uncleaned instruments of each type (n = 177) was also analysed for adherent protein using ophthalaldehyde/N-acetylcysteine reagent. MAIN OUTCOME MEASURES: Residual protein levels allowed comparisons to be made on the effectiveness of different cleaning processes. RESULTS: One thousand, three hundred and four instruments were analysed. Observational data demonstrated several shortcomings in cleaning chemistries and operation of the AWD. For uncleaned instruments, median residual protein levels ranged from 0.4 µg (stainless steel burs) to 462 µg (extraction forceps). Following manual washing, median protein levels ranged from 0.3-78 µg; for manual plus ultrasonic washing, levels ranged from 9-39 µg and AWD levels ranged from 0.3-27 µg. Manual washing combined with ultrasonic cleaning was significantly less effective than the other two processes (p <0.008). AWDs reduced the variability in the cleaning process. No correlation was found between visual scoring and residual protein determination. CONCLUSION(S): There was a wide variation in residual protein levels both within and between different methods and instruments and this underlines the complexity of this process.

Genetic diversity of the major histocompatibility complex class II in Alaskan caribou herds.

We have sampled five different herds of caribou in Alaska to ascertain their major histocompatibility complex (MHC) class II diversity, and to assess whether the herds were significantly different in their MHC class II allele profiles. We complemented the MHC results with data from nine neutral microsatellite markers. The results indicate that while the microsatellites are diverse, there are no significant differences between the herds. However, for the MHC, we have shown that there is diversity at three of the four loci studied, the different herds have significantly different MHC class II allele profiles. It is also clear that although some of the herds have overlapping ranges, they are still different for their MHC class II alleles.

A validated miniaturized MPN method, based on ISO 6579:2002, for the enumeration of Salmonella from poultry matrices.

AIMS: To validate the effectiveness of a miniaturized most probable number method (mMPN) in enumerating Salmonella from poultry matrices. METHODS AND RESULTS: A MPN was developed, based on the ISO 6579:2002 method using modified semi-solid Rappaport-Vassiliadis media as the sole selective medium. The validation of the mMPN was shown to not differ significantly from, at the 95% confidence level (Student's t-test P = 0·357) to, the traditional 9-tube MPN (tMPN) using pure cultures of Salmonella ser. Typhimurium, Infantis, Montevideo, Muenster and Salmonella subsp II 1,4,12,27:b:[e,n,x] (Sofia). The validation of naturally and artificially contaminated poultry matrices (carcasses, scald tank water, faeces, caeca and feed) showed that detection using the mMPN compared well to the ISO 6572:2002; sensitivity (92%), specificity (97%) and agreement (KAPPA 0·72). The quantitative comparison between the tMPN and mMPN methods showed that 92% of enumerations were less than ± 1 log different (Student's t-test = 0·13). Financial analysis showed that the mMPN required 64% less media and 56% less labour than the tMPN. CONCLUSION: The mMPN is a consistent, easy to automate method for the enumeration of Salmonella from different poultry matrices. SIGNIFICANCE AND IMPACT OF STUDY: The miniaturized MPN reduces the material and labour cost of the method and enables the uniform and accurate measurement of the effectiveness of intervention strategies in the control of Salmonella colonization of poultry.

Effects of vaccine dose, virus challenge dose and interval from vaccination to challenge on protection of broiler chickens against Marek's disease virus challenge.

OBJECTIVES: To examine the effects of varying the doses of turkey herpesvirus (HVT) vaccine and Marek's disease virus (MDV) challenge at two intervals after vaccination on the protection of chickens against challenge with MDV. DESIGN AND PROCEDURE: Experiment 1, a dose response study, consisted of 11 doses of HVT vaccine administered at hatch followed by challenge with 100 plaque forming units (pfu) of MDV 5 days post vaccination. Experiment 2, a 2 x 6 x 2 factorial design, included two HVT vaccine types, six different doses of HVT vaccine and 50 pfu and 200 pfu of MDV challenge 2 days post vaccination. All chickens were reared up to day 56 post challenge when all survivors were killed humanely. Dead and killed chickens were examined for gross MD tumours. RESULTS: Experiment 1 showed a significant positive linear relationship between dose of HVT vaccine and protective index in chickens challenged 5 days post vaccination. However the range of protective index observed was limited. In Experiment 2 neither HVT vaccine provided significant protection at any dose. There was no significant effect of vaccine type or MDV challenge dose on overall protection against challenge. Chickens challenged with 200 pfu of MDV had significantly higher mortality and MD incidence than those with 50 pfu. CONCLUSIONS: HVT vaccine dose had a significant impact on protective index, but vaccination to challenge interval appeared to have greater impact on the protective efficacy of vaccination. A fourfold increase in challenge dose increased mortality rate and incidence of MD.

Synthesis of triclinic calcium pyrophosphate crystals.

This paper presents a method for preparing crystals of triclinic calcium pyrophosphate (t-CPPD). A calcium pyrophosphate intermediate is first prepared by reaction of potassium pyrophosphate and calcium chloride. Samples of the intermediate are dissolved in hydrochloric acid and urea added. Upon heating to 95-100 degrees C, hydrolysis of the urea causes the pH to rise and t-CPPD crystallises out. Purity of the product was ascertained by chemical and physical analysis. Where large crystals are required an unstirred system is used, while smaller crystals are produced by stirring the reaction mixture.

A case of sepsis caused by Acidovorax.

This report documents a case of sepsis caused by a recently recognized environmental organism and demonstrates the pathogenicity of this bacterium in the clinical setting.

Evolution and phylogeny of old world deer.

The phylogenetic pattern and timing of the radiation of Old World deer was determined based on the complete mitochondrial cytochrome b gene from 33 Cervinae taxa. Using rooted and unrooted phylogenies derived from distinct theoretical approaches, strong support was achieved for monophyly of the Old World deer with muntjacs as sister group as well as for the divergence of at least three distinct genera: Rucervus, Dama, and Cervus. The latter clade comprises what have previously been regarded as the genera or subgenera Panolia, Rusa, Cervus, Sika, and probably Przewalskium. Our data also consistently confirmed paraphyly of nominate C. elaphus and did not support the monophyly of Axis. We used these molecular phylogenies to assess the homoplastic evolution of morphological, geographical, ecological, and selected behavioural character state differences within the Cervinae. Reliable fossil calibrations, large molecular data sets, and improved dating methods are shaping a molecular time scale for the evolutionary radiation of Old World deer that occurred at the Miocene/Pliocene transition and is largely compatible with existing palaeontological evidence. Using node ages estimated from sequence data, we estimated an average per-lineage diversification rate of 0.51+/-0.1 species per million years (my) over roughly the last 6 mya.

Post-sternotomy internal mammary arteriovenous fistula.

Arteriovenous fistula from the mammary artery is a rare complication following cardiac surgery. The fistula usually develops within the first 2 weeks after surgery and is initially asymptomatic. Typically, a continuous machinery murmur is heard along the parasternal border of the chest wall. A patient with an arteriovenous fistula between the right internal mammary artery and mammary vein following a combined aortic valve and coronary bypass operation is described. A transthoracic colour Doppler scan led to the diagnosis of the fistula. Because of potential late complications endovascular embolisation of the fistula was successfully performed.