The Impact of Different Sources of Zinc, Manganese, and Copper on Broiler Performance and Excreta Output

Commercial premixes provide trace minerals (TM) such as zinc (Zn), manganese (Mn), and copper (Cu) in excess of the requirements to maximize broiler performance. High inclusion levels of TM in broiler feed and their low absorption in the gastrointestinal tract leads to increased levels of TM in the excreta, resulting in the contamination of the environment. A 35-day broiler trial was conducted with 2880 one-day-old Cobb broiler males to test the effect of the supplementation of different sources of TM on growth performance, while evaluating levels in the excreta. Inorganic (ITM), organic (OTM), and hydroxy (HTM) sources of TM were tested against a positive control of current recommended levels of ITM. At 35 d, birds fed HTM were 55 g (p < 0.05) heavier than those fed ITM at the same inclusion level. In contrast, birds fed the control, OTM, and HTM showed no significant difference in body weight. Providing broilers with HTM significantly (p < 0.05) reduced Zn and Cu excretion at 35 d of when compared to those who were fed diets containing ITM or PC. Supplementing different sources of TM to broiler diets at levels below the recommendations showed no negative effect on broiler performance. The use of HTM significantly reduced TM excretion in broilers. The use of HTM in broiler diets can maintain broiler performance and reduce the negative impact on the environment.

The effects of supplemental levels of inorganic zinc, manganese and copper on growth performance in commercial broilers

Commercial broiler premixes provide trace minerals (TMs) such as Zinc (Zn), Manganese (Mn) and Copper (Cu) above the birds' requirements to maximise broiler performance. High inclusion levels of TM and their low absorption in the broiler's gastrointestinal tract have led to increased TM levels in their litter, raising concerns about TM's accumulation in the environment from poultry litter. A 35-day broiler trial was conducted at a broiler facility with 2 880-day-old Cobb 500 broiler males. The objective was to evaluate whether decreasing inorganic Zn, Mn and Cu levels in broiler diets would have a negative effect on broiler growth parameters such as BW, average daily gain, cumulative feed intake (FI) and feed conversion ratio (FCR). Consequently, these minerals were supplemented at 100%, 50%, 25%, and 0% of the Cobb standards. No significant difference in FI and FCR was observed between the treatments for the first 21 days, and there were no significant differences in BW between the positive control, negative control (NC), and 50% of Cobb recommended levels at day 35. However, BW for the NC was significantly higher than the 25% level. These results show that reducing TM levels in broiler diets below commercially recommended levels had no negative effect on broiler performance, with the subsequent economic benefits for producers.

Analysis of gene expression in carbon tetrachloride-treated rat livers using a novel bioarray technology

The present study successfully utilizes a new ADME Rat Expression Bioarray, containing 1040 metabolism- and toxicology-linked genes, to monitor gene expression from the livers of rats treated with carbon tetrachloride (CCl(4)). Histopathological analysis, hierarchical clustering methods, and gene expression profiling are compared between the control and CCl(4)-treated animals. A total of 44 transcripts were found to be altered in response to the hepatotoxin, 19 of which were upregulated and 25 were downregulated. Some of these gene expression changes were expected and concurred with previously published data while others were novel findings.

Discovery and initial structure-activity relationships of trisubstituted ureas as thrombin receptor (PAR-1) antagonists

Thrombin is the most potent agonist of platelet activation, and its effects are predominantly mediated by platelet thrombin receptors. Therefore, antagonists of the thrombin receptor have potential utility for the treatment of thrombotic disorders. Screening of combinatorial libraries revealed 2 to be a potent antagonist of the thrombin receptor. Modifications of this structure produced 11k, which inhibits thrombin receptor stimulated secretion and aggregation of platelets.

Nanomolar-affinity, non-peptide oxytocin receptor antagonists

Non-peptide antagonists of the peptide hormone oxytocin (OT) with nanomolar OT receptor affinities are described. These compounds incorporate novel amido- and amidoalkylcamphor variations to the lead structure L-366,509 (1) to achieve receptor affinity enhancements of 2-3 orders of magnitude over that compound. The new OT antagonist L-367,773 (35) is shown to be an orally bioavailable agent with good duration in vivo and to inhibit OT-stimulated uterine contractions effectively in several in vitro and in vivo models.

Recurrent painful calf swelling associated with gout

A 30-year-old man had a recurrent painful calf swelling associated with gout that mimicked thrombophlebitis and possibly muscle tear. This painful calf swelling occurred in the absence of a subjective history of arthritis of the knee. A constellation of clinical signs was highly suggestive that gout was the cause of the painful calf swellings. Patients with similar conditions, after careful exclusion of thrombophlebitis, might be spared unnecessary and potentially dangerous anticoagulation or surgical intervention by early diagnosis of gout.

H3T-labelled blood cells in the CNS response to axotomies at various times after isotope injection

Numerous investigators, using tritiated thymidine to label mononuclear blood cells, have proposed a hematogenous origin for some of the reactive cells responding to injury in the CNS. However, two questions have remained unanswered: recirculation of H3T at the time of injury with labelling of proliferating local cells; and local reutilization of label released from degenerating cells. In a recently reported experiment using bilateral injuries made at different times (24), a large number os labelled cells responding to the second injury resulted from mitosis of cells already reacting to injury on the contralateral side. Additionally, the possibility that some of the labelled cells could have been newly drived from blood was not ruled out. The present experiment was designed to further explore this possibility. To minimize the problems of H3T recirculation and reutilization, the isotope was injected 3 to 17 days before nerve injury in some of the animals. At sacrifice, labelled cells were found in the nucleus of the injured nerve up to 36 days after isotope injection, with the peak of the reaction occurring at 9 days. Since the isotope was injected 3 to 17 days before injury and because there was no source of reactive cells on the contralateral side, it was felt that these labelled cells were newly derived from blood.

Effect of bilateral nerve injury on the migration of labelled mononuclear cells to hypoglossal nuclei

Whether cells responding to injury in the central nervous system are of local or hematogenous origin is still a question that has not been answered unequivocally, although ample evidence in favor of a dual origin exists. In the present investigation, mononuclear blood cells were labelled with 3HT one day before left hypoglossal nerve injury. In addition to the initial injury, some of the animals received an injury of the right nerve at a later time. The fate of labelled cells responding to the initial injury when a second injury was made was studied. With two lesions the total number of labelled cells responding was twice the number present with a single lesion at the period of peak response. This was more than could be accounted for by simple migration from left to right. The data presented suggest that mitosis and migration of cells present at the initial lesion accounted for part of the increased number of cells. The possibility that some of the cells responding to the second injury were of recent hematogenous origin was not ruled out.