Effect of early photostimulation at 15-weeks of age and everyday spin feeding on broiler breeder performance.

To prevent broiler breeders from growing too quickly and becoming too large for optimum reproduction, their dietary intake is restricted. While current restricted feeding programs, such as skip-a-day feeding (SAD), improve the economic efficiency of broiler breeder operations, this management practice impacts bird welfare. There is an interest in finding strategies that could reduce the impact of feed restriction during broiler breeder rearing. This research investigated the effects of feeding pullets on an advanced growth curve for early photostimulation at 15 wk (15P) or standard growth curve for photostimulation at 21 wk (21P), using either an every-day-spin feeding program (EDS) or SAD feeding, on the reproductive parameters of broiler breeder hens in a 2 × 2 factorial arrangement. Overall, advancing the growth curve (15P) decreased blood corticosterone levels compared to 21P, but EDS resulted in higher blood corticosterone levels compared to SAD. At the end of rearing in both 15P and 21P, EDS pullets weighed less than SAD pullets. The onset of egg production was 20 and 24 wk of age for the 15P and 21P hens, respectively. Despite an earlier onset, 15P hens did not produce more eggs than 21P hens through 65 wk of age. Egg weight was reduced for 15P compared to 21P until 30 wk of age. The 15P hens had a greater number of double yolk eggs than the 21P hens. Fertility and hatch were not impacted by the advanced growth curve and early photostimulation. Although the current research indicates the potential to reduce feed restriction associated welfare issues by rearing broiler breeder pullets for an earlier photostimulation onset, further research in needed to determine if this management technique can be improved to optimize hen reproductive efficiency.

Angiotensin-(1-7) administration benefits cardiac, renal and progenitor cell function in db/db mice.

BACKGROUND AND PURPOSE: Diabetic patients are at an increased risk of cardiovascular disease, in part due to inflammation and oxidative stress. These two pathological mechanisms also affect other organs and cells including the kidneys and progenitor cells. Angiotensin-(1-7) [Ang-(1-7)] has previously been shown to counterbalance pathological effects of angiotensin II, including inflammation and oxidative stress. The aim of this study was to investigate the effects of short-term (2 weeks) Ang-(1-7) treatment on cardiovascular and renal function in a mouse model of type 2 diabetes (db/db). EXPERIMENTAL APPROACH: Eight- to nine-week-old db/db mice were administered either vehicle, Ang-(1-7) alone, or Ang-(1-7) combined with an inhibitor (losartan, PD123319, A-779, L-NAME or icatibant) daily for 14 days. KEY RESULTS: An improvement in physiological heart function was observed in Ang-(1-7)-treated mice. Ang-(1-7) also reduced cardiomyocyte hypertrophy, fibrosis and inflammatory cell infiltration of the heart tissue and increased blood vessel number. These changes were blocked by antagonists of the MAS1, AT2 and bradykinin receptors and inhibition of NO formation. Treatment with Ang-(1-7) reduced glomerular damage and oxidative stress in kidney tissue. Bone marrow and circulating endothelial progenitors, as well as bone marrow mesenchymal stem cells, were increased in mice treated with Ang-(1-7). CONCLUSIONS AND IMPLICATIONS: Short-term Ang-(1-7) treatment of young db/db mice improved heart function and reduced kidney damage. Treatment also improved bone marrow and circulating levels of endothelial and mesenchymal stem cells. All of this may contribute to improved cardiovascular and renal function.

The impact of proposed changes in liver allocation policy on cold ischemia times and organ transportation costs.

Changes to the liver allocation system have been proposed to decrease regional variation in access to liver transplant. It is unclear what impact these changes will have on cold ischemia times (CITs) and donor transportation costs. Therefore, we performed a retrospective single center study (2008-2012) measuring liver procurement CIT and transportation costs. Four groups were defined: Local-within driving distance (Local-D, n = 262), Local-flight (Local-F, n = 105), Regional-flight <3 h (Regional <3 h, n = 61) and Regional-Flight >3 h (Regional >3 h, n = 53). The median travel distance increased in each group, varying from zero miles (Local-D), 196 miles (Local-F), 384 miles (Regional <3 h), to 1647 miles (Regional >3 h). Increasing travel distances did not significantly increase CIT until the flight time was >3 h. The average CIT ranged from 5.0 to 6.0 h for Local-D, Local-F and Regional <3 h, but increased to 10 h for Regional >3 h (p < 0.0001). Transportation costs increased with greater distance traveled: Local-D $101, Local-F $1993, Regional <3 h $8324 and Regional >3 h $27 810 (p < 0.0001). With proposed redistricting, local financial modeling suggests that the average liver donor procurement transportation variable direct costs will increase from $2415 to $7547/liver donor, an increase of 313%. These findings suggest that further discussion among transplant centers and insurance providers is needed prior to policy implementation.

Angiotensin-(1-7) administration reduces oxidative stress in diabetic bone marrow.

Diabetics have an increased risk of developing cardiovascular disease, in part due to oxidative stress, resulting in endothelial nitric oxide synthase (eNOS) dysfunction. Studies have demonstrated that angiotensin-(1-7) [Ang-(1-7)] can activate eNOS activity. Because the bone marrow is a primary source of a number of progenitors important in physiological homeostasis and healing, the goal of this study was to evaluate the in vivo effects of Ang-(1-7) treatment on oxidative stress and the ensuing nitrative stress in diabetic bone marrow and its potential pathways. BKS.Cg-Dock7(m) +/+ Lepr(db)/J mice and their heterozygous controls were administered Ang-(1-7) alone or combined with A-779, losartan, PD123,319, nitro-l-arginine methyl ester, or icatibant sc for 14 d. The bone marrow was then collected to measure nitric oxide levels, eNOS phosphorylation, and expression of nitric oxide synthase, superoxide dismutase, and p22-phox. Nitric oxide levels in the bone marrow were significantly decreased in diabetic mice, and Ang-(1-7) treatment was able to significantly increase these measures (P < 0.01). This effect was blocked by the coadministration of PD123,319, A-779, nitro-l-arginine methyl ester, and icatibant. In addition, Ang-(1-7) treatment reversed the paradoxical increase in eNOS and neuronal nitric oxide synthase expression and decreased the phosphorylation of eNOS at Thr495 seen in diabetic mice. Ang-(1-7) also reversed diabetes-induced production of reactive oxygen species by decreasing p22-phox expression and increasing superoxide dismutase 3 expression, leading to a significant reduction in 3-nitrotyrosine formation in diabetic bone marrow (P < 0.05). Our findings demonstrate that Ang-(1-7) administration decreases diabetes-induced oxidative stress in the bone marrow and modifies pathways involved in eNOS dysfunction.

Dicloxacillin absorption and elimination in children.

We determined the apparent bioavailability of dicloxacillin in 26 children between the ages of 0.24 and 143 months by comparing the area under the serum concentration versus time curve following intravenous and oral administration of 25 mg/kg. With intravenous infusion the overall mean half-life of elimination was 0.53 +/- 0.20 h, the AUC was 70.15 +/- 32.18 mg.min/l and the apparent volume of distribution was 0.29 +/- 0.09 l/kg. The overall average bioavailability was 59.89%. Children less than 6 months old had a shorter time to peak concentration (1.39 +/- 0.49 h) and the lowest oral bioavailability (64.35 +/- 13.62%) in comparison to children more than 60 months old. In children older than 60 months the time to peak was 1.79 +/- 1.16 h and the average oral bioavailability was 79.38 +/- 32.87%. However, children less than 6 months old had the least variability in absorption, the coefficient of variation (CV) of oral bioavailability was 13.62%, while in children between 6 and 40 months old the CV was 60.4%: children older than 60 months had the most variability in absorption, a CV of 32.87%. This variability was not dependent on the formulation administered. After 5 years of age the bioavailability increased with increasing age.

A model for polygenic inheritance of abdominal tergal scale pattern in Aedes aegypti.

There is much variation in the amount of white scaling on the abdominal tergites of Aedes aegypti. The genetic basis for this white scale pattern was investigated in two laboratory strains established by selection from the CARN Strain of Ae. aegypti. These experimental strains were crossed in all possible directions in single pair matings. Based on analysis of their progeny it is proposed that genes at three separate independently assorting loci control abdominal tergal scale pattern. Correlation of observed data and expected data was high. Since the abdominal tergal scale pattern in Ae. aegypti appears to be controlled by one major polygenic system with modifiers, it is proposed that it is better to consider differences in ethology, physiology, and reproductive behavior as the bases for separation of the species into intraspecific groups.