Effects of In Ovo feeding of dextrin-iodinated casein in broilers: I. Hatch weights and early growth performance.

This study was conducted to determine the effect of in ovo feeding of dextrin (Dext) and iodinated casein (IC) on hatch and early growth in broilers. Three experiments were conducted at a commercial hatchery using a commercial Inovoject™ system with treatments occurring in conjunction with vaccination at transfer from incubator to hatcher units (18.5 to 19 d embryonic development). In all 3 experiments, approximately 15,000 eggs (2,500 eggs per group) were treated and transferred to a single hatcher unit. Treatments in Exp. 1 consisted of buffered saline solution alone (Control, Cont) or a dextrin solution (Dext, 18% maltodextrin, 10% potato starch dextrin) containing zero, 80, 240, 720, or 2,160 µg IC/mL. The results of this initial experiment indicated that broiler chicks at hatch that received 240 and 720 µg IC/mL in Dext were heavier (P < 0.05) compared to the other treatment groups; there were no differences in hatchability between groups. Based on these findings, subsequent studies used treatments of zero, 240, and 480 µg/mL IC in Dext or Cont. In Exp. 2, hatch weights in all treatment groups were higher (P < 0.05) compared to those receiving Cont. In Exp. 3, chicks given Dext alone or 240 and 480 µg/mL in saline weighed less at hatch compared to the other treatment groups. However, chicks provided Dext alone in Exp. 3 had less weight loss after a 24-hour holding period compared to the other groups. All treatment groups exhibited greater weight gain from one to 10 d compared to the Cont group. The results indicate that in ovo feeding of broiler embryos with Dext containing 240 and 480 µg IC/mL may have beneficial effects on broiler hatch weights and early growth rate.

Effect of in ovo feeding of dextrin-iodinated casein in broilers: II. Hatch window and growth performance.

Studies were conducted using a commercial InovojectTM system to determine effects of in ovo feeding of dextrin and iodinated casein (IC) on hatch and posthatch growth in broilers. At ∼18.5 d embryonic development, eggs were treated with 0, 240, or 480 µg IC/mL in saline (Cont, IC240, and IC480) or dextrin (Dext, DextIC240 and DextIC480). The Dext solution consisted of 18% maltodextrin and 10% potato starch dextrin; saline was the vehicle used by the company for in ovo vaccination. The volume for all in ovo treatments was 50 µL/injection. Eggs in Experiment 1 were transferred to a commercial hatcher unit whereas eggs in Experiments 2 and 3 were transferred to a research hatcher unit to assess effects of treatments on timing of hatch. At hatch, chicks were randomly selected and placed in floor pens and grown to 6 wk. In Experiment 1, there were no differences in hatch weights, but broilers provided Dext IC240 in ovo were heavier (P < 0.05) at 6 wk compared to other treatments with the exception of the Dext IC240 group. In Experiment 2, hatch weights were heavier (P < 0.05) in chicks receiving IC240 and DexIC480 treatments compared to Controls. At 6 wk, broilers in all treatments were heavier (P < 0.05) than Cont with the exception of IC480. In Experiment 3, hatch was stimulated by IC240 (in saline), but was delayed by Dext IC240. Serum analysis of ß-hydroxybutyrate (µM/mL), as an indicator of ketone accumulation from fat metabolism of chicks held in chick boxes for 24 h posthatch (to simulate delay in placement after hatch), indicated that chicks in the IC240 group (that hatched earlier) had higher blood ketones compared to chicks that received Dext or DextIC240 in ovo (that hatched later). We conclude dextrin and iodinated casein (240 µg/mL) provided in ovo (∼18.5 d of embryonic development) has the potential to improve chick quality and posthatch body weight by delaying or narrowing hatch window.

Improved hatchability and posthatch performance in turkey poults receiving a dextrin-iodinated casein solution in ovo.

Two experiments were conducted with a commercial turkey company using a commercial egg injection system to investigate the effect of a dextrin-iodinated casein solution injected in ovo at 25 d of incubation on turkey poult hatchability, hatch weight, and growth (6 or 7 d posthatch). In experiment 1, a total of 3,900 turkey eggs (1,300 per group) were injected at 25 d of incubation with either 200 µL of a control (physiological saline) solution or a dextrin solution (18% maltodextrin and 10% potato starch dextrin) with 75 or 375 µg/mL of iodinated casein (DexIC75 or DexIC375, where Dex and IC refer to dextrin and iodinated casein, respectively). Two hundred poults from each group were neck-tagged, weighed (hatch weight), placed in a commercial turkey house within a single brooder ring, and weighed again (7 d posthatch). In experiment 2, a total of 5,200 eggs (2,600 per group) were injected with the control or DexIC75 solution. A total of 600 poults (300 per group) were neck-tagged and hatch weights were obtained, followed by placement in a single brooder ring in a commercial house and a second weighing (6 d posthatch). Eggs in experiments 1 and 2 were obtained from hen flocks that were 33 and 5 wk into the laying cycle, respectively. In experiment 1, the DexIC75 injection resulted in a 1.8% increase (P = 0.03) in hatch weight. In experiment 2, the DexIC75 treatment resulted in a 2.4% increase in hatchability (P = 0.01), a 4.3% increase in hatch weight (P < 0.001), and a 1.8% increase in 6-d poult weights (P < 0.03) compared with controls. Results of this study indicate that a solution containing dextrin and 75 µg/mL of iodinated casein injected into turkey eggs at 25 d of incubation may be used to improve early poult weights, hatchability, or both in commercial turkey production.

Studies on experimental iodine allergy: 2. Iodinated protein antigens and their generation from inorganic and organic iodine-containing chemicals.

We hypothesize that iodine allergy is an immune response to iodinated autologous proteins generated in vivo from iodine-containing organic and inorganic chemicals. In this report, effects of protein iodination on elicitogenic activity in guinea pig iodine allergy model and iodinated protein antigen generation in vitro from iodine-containing chemicals were investigated. Active cutaneous anaphylaxis (ACA) and delayed-type hypersensitivity (DTH) tests were performed in guinea pigs immunized with iodine. The amount of iodine (I2) reacted to proteins for giving them an eliciting activity of ACA was > or = 0.15 micromol for 1 mg of albumin. DTH reactions were provoked by intradermal injection of 10(6) PECs reacted with > or = 0.075 micromol of I2. I2 was generated from a potassium iodide (KI) solution or iodinated contrast media by UV light irradiation. X-ray irradiation of KI and iodinated contrast media in the presence of protein resulted in the generation of iodinated protein antigens. The generation of iodinated protein antigens was inhibited in the presence of reducing agents. Therefore, it is noteworthy that iodine allergy of the present hypothesis is dependent on reactive oxygens. By presenting these ex vivo and in vitro data, we discuss the possibilities for the generation of iodinated protein antigens in vivo.

Plasma thyroid hormones, growth and carcass measurements of genetically obese and lean pigs as influenced by thyroprotein supplementation.

A 2 X 2 factorial arrangement with two genotypes of pigs (genetically obese and lean) and two dietary treatments (basal, a 16% protein corn-soybean meal standard grower diet, and basal +220 ppm thyroprotein as iodinated casein) was used. The 28 gilts were housed individually and fed ad libitum from 121 d of age until slaughtered at 99 kg body weight. Compared with lean pigs, genetically obese pigs had significantly lower average daily gain and gain/feed, greater backfat thickness, smaller loin eye area, shorter carcass length and lower circulating plasma triiodothyronine (T3) concentration. However, both total plasma and free thyroxine (T4) concentrations were similar comparing obese and lean pigs. Supplementation with thyroprotein increased circulating plasma concentration of both total and free T4 and produced interactions with genotype in affecting daily gain and gain/feed of pigs. Thyroprotein reduced both daily gain and gain/feed in obese pigs, but increased daily gain and gain/feed in lean pigs. It is suggested, similar to the case with obese mice, that heat production of our genetically obese pigs may be more sensitive to thyroprotein administration compared with similar treatment of lean animals.

The effect of methionine, thiouracil, dienestrol diacetate and thyroprotein on the development and prevention of fatty liver in pullets.

The effect of two levels each of methionine (0.0 and 0.07 percent), thiouracil (0.0 and 0.05 percent), dienestrol diacetate (0.0 and 0.007 percent), and thyroactive casein (0.0 and 0.0125 percent) on the performancy, organ changes, and liver composition in 640 pullets of two strains was studied in a 24 factorial arrangement of treatments. Egg production, egg characteristics, feed conversion, organ weights, and liver composition were parameters measured. Supplemental methionine increased the phosphorus content of liver fat in strain A, but other parameters in the two strains were mot affected by the increase in dietary methionine. The thiouracil increased weight grains, gram of fat per total liver, percent of liver fat, thyroid weight, and heart weight but decreased the phosphorus content of liver fat. Nine typical cases of fatty liver syndrome with large liver hematomas occurred in the thiouracil treated birds and one case occurred in an untreated pullet. Dienestrol diacetate did not affect egg production, egg characteristics, organ weights, and liver composition in the two strains. Thyroprotein decreased weight gain, abdominal fat, liver weight. liver fat, thyroid weight, and percent red cells, but decreased percent blood sports in eggs and adjusted weights of the kidney and heart in both strains.