Dietary inclusion of AZOMITE improves feed efficiency in broilers and egg production in laying and broiler breeder hens

The dietary inclusion of aluminosilicates has been reported to enhance pellet quality, improve feed mill throughput, bind toxins, improve feed efficiency, and promote immunological function across a variety of production systems. AZOMITE is a product marketed as a hydrated sodium calcium aluminosilicate containing macro and trace minerals, and rare earth elements and the potential benefits of its dietary inclusion in broiler, layer, and broiler breeder diets was investigated. In a battery study, broilers were fed diets containing 0, 0.125, 0.250, or 0.500% AZOMITE from 0 to 21 d of age. Laying hens were fed a control diet or this diet supplemented with 0.25% AZOMITE from 54 through 98 wk of age, with the hens fed a standard molting diet or this diet supplemented with 0.25% AZOMITE from 71 to 72 wk of age. Broiler breeder hens were fed a control diet or this diet supplemented with 0.25% AZOMITE from the onset of photostimulation at 21 wk of age through 65 wk of age. All 3 dietary inclusion rates of AZOMITE improved (P < 0.05) the feed to body weight gain ratio in broilers fed these diets relative to broilers fed the control diet. In laying hens total marketable eggs, and in broiler breeder hens total settable eggs were increased (P < 0.05) with the dietary inclusion of AZOMITE by 8 eggs per hen. The inclusion of dietary AZOMITE also improved apparent Ca and P digestibility in broilers and tibia ash content in laying hens. The results indicate the dietary inclusion of AZOMITE in poultry diets improves bird performance.

Early photostimulation at the recommended body weight reduced broiler breeder performance

To synchronize the onset of sexual maturity in the face of high BW variation, the age at photostimulation has been increasing in the broiler breeder industry. This experiment studied the effects of increased BW and earlier photostimulation on broiler breeder reproductive performance where within-treatment BW uniformity was very high. The experiment tested BW and age at photostimulation treatments in a 2 × 2 factorial arrangement. Hens (n = 120) were fed with a precision feeding system to allocate feed individually following the breeder-recommended target BW (Standard) or to a 22% heavier target BW curve reaching the Standard 21 wk BW at 18 wk (High). Hens were photostimulated at either 18 wk (18WK) or 21 wk (21WK) with a 16L:8D photoschedule. Age at first egg (AFE) and individual egg production to 55 wk were recorded. Differences were reported as significant if P ≤ 0.05. The AFE was decreased and maturation interval between photostimulation and AFE was shorter for hens on the High BW treatment compared to the Standard BW treatment (178.1 vs. 194.7 d and 41.8 vs. 58.2 d, respectively). Hens on the 21WK treatment had a decreased AFE compared to the 18WK treatment (177.0 d vs. 195.9 d) and their maturation interval was shorter (30.0 d vs. 69.9 d). The CV for AFE was higher in the 18WK treatment compared to the 21WK treatment (28.2% vs. 11.2%). Total egg production was higher for hens on the High BW treatment compared to the Standard BW treatment (129.4 vs. 92.8, respectively). Total egg production was higher for hens on the 21WK treatment compared to the 18WK treatment (138.4 vs. 83.8, respectively). Egg weight of Standard BW × 18WK hens was lower compared to High BW × 18WK hens. Current recommended breeder BW may be too low for optimal sexual maturation after photostimulation. It is concluded that even when BW variation is minimized, photostimulation at 18 wk of age is not recommended.

The effect of dietary alterations during rearing on growth, productivity, and behavior in broiler breeder females

Parent stocks of meat birds are severely feed restricted to avoid obesity-related health and fertility problems. This restriction often leads to chronic hunger, accompanied by stereotypic behavior. Research based in the United Kingdom has shown that using diets containing fiber and appetite suppressants may relieve some of the symptoms of hunger. However, few data are available regarding North American-sourced ingredients or nondaily feeding regimens. This study investigated the effects of 2 alternative diets, in combination with 2 feeding frequencies on growth, productivity, and behavior in broiler breeders. Six dietary treatments were tested, each with 5 replicate pens of 12 or 13 birds. Control diets consisted of a commercial crumble, fed on a daily or skip-a-day (SAD) basis. Alternative diets included soybean hulls as a fiber source, and calcium propionate as an appetite suppressant of either a feed-grade or purified quality, fed on either a daily or SAD basis. Birds were weighed weekly and egg production was recorded daily. Video cameras were used to record behavior during and following the morning feeding bout every 2 wk from 11 to 28 wk. Data were analyzed with a mixed model ANOVA, with repeated measures. Diet, feeding frequency, time, or an interaction of the 3 had significant effects on all observed behavior during rearing. These differences appeared to diminish during lay, with most stereotypic behavior no longer present. Very little object pecking and aggression was observed during and immediately following feeding bouts; however, daily-fed control birds still displayed this behavior more often, especially during rearing (P = 0.015). During feeding bouts, SAD birds feather pecked (P = 0.003) and rested more (P = 0.0002) than daily-fed birds. Control birds feather pecked most often (P = 0.033) after feeding bouts. Overall, the feed-grade diet appeared most effective at reducing hunger-related behavior, and the control diet appeared the least effective. There was little conclusive evidence to show that daily feeding was more effective at reducing hunger.

A model for an economically optimal replacement of a breeder flock

A deterministic model is developed to support the tactical and operational replacement decisions at broiler breeder farms. The marginal net revenue approach is applied to determine the optimal replacement age of a flock. The objective function of the model maximizes the annual gross margin over the flock's production cycle. To calculate the gross margin, future egg production, fertility, or hatchability of the eggs, revenues and variable costs of a flock were estimated. For tactical decisions, the optimal laying length is the age at which the average gross margin of an average flock is maximal. For operational decisions, a flock should be replaced when the marginal gross margin of a replaceable flock is less than the average gross margin of an average flock. To demonstrate the model, a broiler breeder flock from a Dutch breeder farm was used. A sensitivity analysis showed that the optimal replacement decision, for both tactical and operational management, is sensitive to the decrease in the weekly egg production after the peak and the prices of feed and hatching eggs. The effect of the decrease in weekly fertility after the peak on the replacement decision is related to the payment system for hatching eggs.