Platelet Volume and Plateletcrit in Dogs with Presumed Primary Immune‐Mediated Thrombocytopenia

Background

Mean platelet volume (MPV) and plateletcrit (PCT) are indices used in evaluating immune‐mediated thrombocytopenia (IMT) in humans and in dogs with congenital macrothrombocytopenia. These indices may provide clinically valuable information in acquired thrombocytopenia.

Hypothesis/Objectives

Dogs with presumed primary IMT will have increased MPV, and therefore platelet mass (PCT) will increase faster than platelet count (PLT) during recovery.

Animals

Forty‐nine dogs with automated PLT < 30,000/μL because of presumed primary IMT and hematocrit (HCT), PCT, MPV, and platelet distribution width determined from the same complete blood count (CBC), and 46 healthy controls.

Methods

Case‐control retrospective study; PLT, PCT, MPV, and platelet distribution width (PDW) were recorded from CBCs from 49 dogs, with 45 having data collected on the day of presentation. Fifteen were confirmed to have attained a PLT ≥ 75,000/μL on at least 1 CBC within 15 days after admission. The PCT equivalent to a PLT of 75,000/μL (assuming an average MPV) was calculated for comparison with PLT in terms of time to achieve a threshold of platelet mass by the 2 measures.

Results

Mean platelet volume was higher in IMT dogs (17.3 fl) than the reference population (10.5 fl) (P < .0001). The PDW was not significantly different among the groups. The median time for PCT to reach threshold in confirmed responders was faster (3 days) compared with PLT (4 days).

Conclusions and Clinical Importance

Immune‐mediated thrombocytopenia is characterized by increased MPV. Time to achieve a threshold PCT tended to be shorter than PLT, suggesting that PCT may be a useful platelet parameter for monitoring dogs with IMT.     

The effect of dietary ractopamine concentration and duration of feeding on growth performance, carcass characteristics, and meat quality of finishing pigs

A total of 400 barrows from Dekalb EB and 83 terminal sires mated to 43 and 45 maternal lines were used to evaluate the effects of dietary ractopamine (RAC; Paylean, Elanco Animal Health, Greenfield, IN) concentrations (0, 5, 10, or 20 ppm; as-fed basis) and feeding durations (6 to 34 d) on growth, efficiency, carcass, and meat quality characteristics of finishing pigs. Barrows were weighed and sorted into five weight blocks, each block consisting of 16 pens (five pigs per pen). Weight blocks were allocated to feeding duration treatments and assigned consecutively by weight from lightest to heaviest to represent 34, 27, 20, 13, and 6 d on test, respectively. The lightest and heaviest blocks averaged 79.8 and 103.8 kg, respectively, at the start of the test. Within a weight block, pens (four per treatment) were randomly assigned to one of four dietary concentrations of RAC in a basal diet containing 18.5% CP and 1.13% lysine. The experiment-wide target slaughter weight was 109 kg, and pigs and feeders were weighed weekly. Weight blocks (80 barrows per block) were slaughtered at a commercial packing plant after 6, 13, 20, 27, or 34 d on test. Overall, RAC supplementation improved (P < 0.05) ADG; however, ADG was not different (P > 0.08) from controls for pigs fed 5, 10, and 20 ppm RAC for 27, 34, and 6 d, respectively. During each feeding period, RAC-fed pigs had improved (P < 0.05) G:F, and, after 20, 27, and 34 d on test, pigs fed 20 ppm RAC had greater (P < 0.05) G:F compared with those fed 0 or 5 ppm RAC. Hot carcass weight was increased (P < 0.05) by RAC feeding after 13 and 27 d of feeding, and by feeding 10 and 20 ppm RAC after 20 d of feeding. After 34 d, pigs fed 20 ppm RAC had heavier (P < 0.05) hot carcass weight than pigs fed 10 ppm RAC. Fat-free lean estimates and the 10th-rib LM area were increased (P < 0.05) by feeding 10 and 20 ppm RAC after 27 d, and by feeding 20 ppm RAC after 34 d compared with controls. Japanese and American color scores, as well as L*, a*, and b* values of the LM, were not affected (P > 0.11) by 5 and 10 ppm RAC compared with controls during each feeding period. Visual marbling score for the LM was decreased (P < 0.05) when RAC was fed at 10 and 20 ppm compared with 0 ppm RAC when fed for 34 d. Dietary RAC improved growth performance at all feeding durations, whereas carcass composition was improved at longer feeding durations. In addition, 5 and 10 ppm RAC did not affect objective and subjective measures of pork quality.     

Performance and genetic analysis of coast redwood cultivars for afforestation of converted grassland in California

New Forests - Afforestation of pasture sites results in a net reduction in atmospheric CO2. Coast redwood (Sequoia sempervirens) is well suited to carbon forestry due to its rapid growth and...     

Hybridisation within Brassica and allied genera: evaluation of potential for transgene escape

Determining the potential for hybridisation between transgenic crops and their relatives is a major component of risk assessment. Recent assessments of the extent of reproductive compatibility between crops and their relatives draw heavily on existing data from experimental crosses to infer the likelihood of hybridisation and introgression. Since the literature in this area continues to grow at a rapid pace, it is essential that such analyses can be easily updated. We used a database approach to assemble data on reproductive compatibility for eight crop species in Brassica, Raphanus and Sinapis, using data from hand pollination, spontaneous (unassisted) pollination and trials using in vitro techniques (e.g. embryo rescue), incorporating 326 studies and 216 species combinations. We found many reports for major crop species (B. juncea, B. napus, B. oleracea and B. rapa), but fewer for minor crops (B. carinata, B. nigra, Raphanus sativus and Sinapis alba). Many species combinations remain untested, and we highlight these information gaps. While reproductively incompatible species can be discounted as targets for transgene escape, compatible species must be evaluated further in the particular context where transgenic crops are grown. Because the data is retained in a database in a relatively unmodified form, multiple views of the data can be generated; this review represents one possible view of this data. Our approach also allows new data to be easily incorporated into future reanalyses and can be extended to other crop groups, and as such is a useful method of assembling, analysing and sharing data for risk assessment. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Potassium recirculation in tomato plants in relation to potassium supply

The Ben Zioni ‐ Dijkshoorn hypothesis that NO₃ uptake by roots is regulated by NO₃ assimilation in the shoot was tested using the tomato plant. Plants were grown at three K levels and the fate of anion charge from NO₃,^‐ and SO₄ ^2‐. assimilation followed in its distribution between organic acid anion accumulation and HCO₃ ^‐ efflux into the nutrient medium. For the high K treatment almost all of this charge was directed towards organic acid accumulation with HCO₃ ^‐ efflux accounting for only 3% of the total charge. On the other hand for plants supplied at the low K level, a substantial proportion of the anion charge was excreted as HCO₃ ^‐ (32%).

Xylem sap analyses and NO₃ reductase assay results indicated that in the tomato plant the upper plant parts constituted the major site for NO₃ reduction. The quantitatively most important ionic constituents in the sap were K⁺, Ca²⁺ and NO₃ ^‐.

Results have been presented that indicate that when K is in short supply in the nutrient medium, K recycling occurs within the plant to facilitate the upward transport of NO₃ ^‐ from root to shoot.     

Fertility impairment in mice on a low fluoride intake

Female mice maintained on a low fluoride diet over two generations showed a progressive decline in litter production. Mice receiving the same diet supplemented with fluoride reproduced normally and at consistent intervals. Addition of fluoride to the intake of females with demonstrated impaired fertility restored their reproductive capacity.