Effects of zilpaterol hydrochloride on retail yields of subprimals from beef and calf-fed Holstein steers

Retail cutting tests were conducted on subprimals from cattle fed zilpaterol hydrochloride (ZH) to determine if the improved carcass composition and red meat yield resulting from ZH feeding would translate into increased retail yields of ready-to-cook products. As part of a 3-phase study, selection of carcasses from Holstein steers was done once (fall 2008), followed by the collection of carcasses from beef-type steers on 2 separate occasions (beef study I: summer 2009; beef study II: spring 2010). Each of the 3 groups of steers was assigned previously to 1 of 2 treatments, treated (fed 8.3 mg/kg of ZH for 20 d) or control (not fed ZH). All steers were slaughtered and carcasses were fabricated in commercial beef-processing establishments. Only those carcasses grading USDA Choice or higher were used. Five subprimals were used for both the calf-fed Holstein study (n = 546 subprimals) and beef study I (n = 576 subprimals): beef chuck, chuck roll; beef chuck, shoulder clod; beef round, sirloin tip (knuckle), peeled; beef round, top round; and beef round, outside round (flat). Seven subprimals were used in beef study II (n = 138 subprimals): beef chuck, chuck roll; beef round, sirloin tip (knuckle), peeled; beef round, top round; beef round, eye of round; beef loin, strip loin, boneless; beef loin, top sirloin butt, boneless; and beef loin, tenderloin. A simulated retail market environment was created, and 3 retail meat merchandisers prepared retail cuts from each subprimal so salable yields and processing times could be obtained. Differences in salable yields were found for the calf-fed Holstein steer chuck rolls (96.54% for ZH vs. 95.71% for control; P = 0.0045) and calf-fed Holstein steer top rounds (91.30% for ZH vs. 90.18% for control; P = 0.0469). However, other than heavier subprimals and an increased number of retail cuts obtained, total salable yields measured on a percentage basis and processing times were mostly unaffected by ZH. Cutability advantages of feeding ZH are achieved primarily in the carcass-to-subprimal conversion rather than in the subprimal-to-retail conversion.     

Reduced fertility in triploids of <Emphasis Type="Italic">Acacia auriculiformis</Emphasis> and its hybrid with <Emphasis Type="Italic">A. mangium</Emphasis>

Polyploid breeding offers the possibility of increased variability in the search for improved growth, site adaptation and disease resistance in tropical acacias. A key focus of breeding in Vietnam has been the production and testing of vigorous triploid clones which are expected to have the added advantage of being sterile. Triploids obtained by manual crosses between diploid and tetraploid trees or by bulk screening of seedlings derived from open-pollinated seedlots were verified using flow cytometry. Thirteen clones are under field testing for growth rate, tree form and fertility. Six of these are now reproductively mature and flowered as prolifically as diploids. However no pollen germinated, either on agar or on their own stigmas under controlled pollination. Only one clone (X01—F₁ hybrid of tetraploid A. mangium and diploid A. auriculiformis) produced open pollinated pods on 0.05% of hermaphrodite flowers and these contained an average of 1.3 filled seeds per pod, about one-fifth the number observed in diploids. Less than 25% of germinated progeny from this triploid clone survived at 3 months after sowing and survivors were severely stunted with arrested growth. Ploidy and genotype analysis revealed them to be predominantly aneuploids, ranging from hyperdiploid to hypotetraploid with 95% being selfs. We are confident that we can select triploid clones which will be effectively infertile if deployed in plantations and may be of particular value in situations where the normal prolific natural regeneration of tropical acacias is highly undesirable.     

The prevalence of feline A/B blood types in the Sydney region

OBJECTIVE: To determine the distribution of A/B blood types in pedigree and crossbred cats in the Sydney region, and to estimate the associated risk of administering incompatible blood in an unmatched random transfusion. DESIGN: A prospective/retrospective study of blood specimens collected from both sick and healthy cats. MATERIALS AND METHODS: Blood was collected from 355 cats from the Sydney region over a 12-year period from 1992 to 2003. Specimens were obtained from 187 domestic crossbred cats (short and long-haired) and 168 pedigree cats. The blood type of each cat was determined by one of three different laboratories using standard methods that varied over the duration of the survey. RESULTS: The distributions of blood types obtained by the three laboratories were not significantly different. The prevalence of type-A, type-B and type-AB blood types in crossbred cats was 62%, 36% and 1.6%, respectively. This is the highest percentage of type-B cats so far reported for an outbred population of domestic cats, and is significantly higher than the 26% reported previously for cats in the Brisbane region. The calculated frequency for the type-B allele assuming Hardy-Weinberg equilibrium for this feline population is 0.60; the corresponding frequency of the type-A allele is thus approximately 0.40. The calculated proportion of random transfusions from this population giving rise to an incompatible blood transfusion is 46%, with half of these being life-threatening events. The calculated proportion of random matings from this population at risk for developing neonatal isoerythrolysis is 23%. The distribution of A and B blood types for pedigree cats was in general agreement with data reported previously for cats in North America and Europe, suggesting that the distribution of blood types in these purebred populations is relatively consistent throughout the world. CONCLUSIONS: The prevalence of type B cats in the owned domestic and pedigree cat population is so high that blood typing or cross matching prior to transfusion should be mandatory, except in Siamese/Oriental cats.     

Bacterial movement at high matric potentials—I. In artificial and natural soils

The rate of active movement of five isolates from three genera of soil bacteria in an artificial and a natural soil at high matric potentials was studied. In nutrient-amended soils the order of motility at matric potentials of —50cm and —150cm of water was: Pseudomonus fluorescens > Bacillis subtilis (two isolates) >Azotobacter vinelandii >Azotobacter chroococcum. The rate of movement of all organisms was markedly greater at the same potential in the artificial soil than in the natural soil. The faster rate in the artificial soil was attributed to the lack of a component with a high surface charge density, onto which bacteria became adsorbed. Though the influence of soil physical factors on microbial activities may be more easily studied in artificial soil systems, the lack of such a component may limit its usefulness in interpreting activities involving adsorption phenomena. Thus, while A. vinelandii moved 26mm in 48 h in the artificial soil at —50cm matric potential, there was negligible movement (5 mm in 48 h) at the same potential in the natural soil. The results indicate that, in contrast to P. fluorescens, Bacillus subtilis and Azatobacter spp. are unlikely to move appreciably through natural soil at matric potentials of less than —150cm of water.     

Effect of osmotic potential on streptomycete growth,antibiotic production and antagonism to fungi

The growth of eighteen isolates of Streptomyces spp. on agars, the osmotic potentials of which were controlled by the addition of various solutes, showed that nine isolates were able to grow at ?100 bars and two of these grew at ?150 bars. This suggests that the water requirements of soil streptomycetes are almost as diverse as those of soil fungi. In general, linear growth and sporulation declined with decreasing osmotic potential, but one isolate grew optimally at potentials between ?5 and ?10 bars. Another isolate formed maximum amounts of a water-diffusible antibiotic per unit colony area at potentials between ?20 and ?35 bars. This appears to be the first report of osmotic potential influencing the production of antibiotic by Streptomyces. The increased antibiotic production at moderate potentials was associated with inhibition of Pythium ultimum, Rhizoctonia solani and a Curvularia sp. by the streptomycete at these potentials on osmotic agar plates. The possible ecological significance of this phenomenon in soil is discussed.     

Septic arthritis,navicular bursitis and osseous cyst‐like lesion in a foal

The purpose of this report is to describe the clinical, imaging and pathological findings in a Quarter Horse colt admitted to the Texas A&M University Veterinary Medical Teaching Hospital for lameness of the left forelimb and left hindlimb. A presumptive diagnosis of left forelimb septic navicular bursitis was made ultrasonographically. A cyst‐like lesion of the calcaneus was diagnosed radiographically and better characterised with computed tomography. The cyst‐like lesion of the calcaneus was caused by infection with Actinobacillus sp. and extended into the adjacent tarsocrural, proximal intertarsal and talocalcaneal joints causing septic arthritis. The owner elected for euthanasia due to the poor prognosis. The diagnoses were confirmed on histopathology.