The effect of quicklime (CaO) on litter condition and broiler performance.

High levels of phosphorus and pathogens in runoff are 2 major concerns following manure applications to fields. Phosphorus losses from fields following manure applications have been linked to the solubility of phosphorus in manure; therefore, by decreasing manure phosphorus solubility, a decrease in phosphorus loss in runoff should be apparent. The objective of this research was to develop a process using quicklime that would result in reduced phosphorus solubility and bacteria counts in broiler litter. The 4 litter treatments evaluated were T1, new wood shavings without the addition of quicklime; T2, used, untreated broiler litter; T3, used litter with 10% quicklime (based on the weight of the litter); and T4, used litter with 15% quicklime (based on the weight of the litter). Body weight, cumulative feed consumption, and feed conversion (feed:BW) were determined on a weekly basis through 42 d of age. Mortality was recorded daily. Carcass weights and percentages of carcass yield without giblets were determined prechill. Litter pH, total phosphorus, nitrogen, soluble phosphorus, litter moisture (%), and total plate counts were measured for each litter treatment on d 7 and 42 after bird placement. No significant differences were found for BW, feed consumption, feed conversion, mortality, carcass weight, or carcass yield. No breast or footpad blisters were observed. On d 7, 15% quicklime had higher (P < 0.001) pH (11.2) when compared with the other treatments. Percentages of phosphorus and nitrogen were lower (P < 0.001) for new wood shavings in comparison with the used litter treatments. Soluble phosphorus (ppm) was lower (P < 0.001) for 15% quicklime (2.75) when compared with new wood shavings (42.2), untreated broiler litter (439.2), and 10% quicklime (35.0). Although not significant, 15% quicklime had lower total plate counts (cfu/g) in comparison with the other treatments on d 1 and 10 postmixing and at 7 d after bird placement. Litter conditions on d 42 after bird placement were similar. We concluded that the use of quicklime as a treatment for broiler litter would initially reduce nitrogen and soluble phosphorus and bacteria counts without negatively affecting bird productivity.

Effects of phosphorus level and phytase in broiler breeder rearing and laying diets on live performance and phosphorus excretion.

The effects of a reduced dietary nonphytate phosphorus (NPP) level and inclusion of phytase on broiler breeder performance and P concentrations in the litter and manure were investigated. Ross 308 broiler breeder pullets and Ross 344 cockerels were placed sex-separate in a blackout growing house and fed standard starter and grower diets to 9 wk of age. At 10 wk of age, 4 treatments (A, B, C, D) were assigned to each of 4 floor pens of 68 pullets and 1 pen of 50 cockerels. From 10 to 21 wk, treatments A to D contained 0.37, 0.27, 0.27, and 0.17% NPP, respectively, with 300 phytase units (FTU)/kg of phytase added to treatments B and D. At 21 wk of age, birds were photostimulated and transferred to a two-thirds slat-litter breeder house with 16 pens of 60 pullets and 6 cockerels. A laying diet was fed from 22 to 64 wk and NPP levels of treatments A to D were adjusted to 0.37, 0.27, 0.19, and 0.09%, respectively, and phytase addition to treatments B and D was increased to 500 FTU/kg. Analysis of the litter from growing pens showed no effect on litter total P when phytase replaced 0.1% of NPP. However, decreasing the dietary NPP by 0.1% without phytase reduced the litter total P by 18%. Water-soluble P (WSP) and the WSP:total P ratio decreased when the grower dietary NPP level was reduced to 0.17% with added phytase and was correlated with litter moisture levels in growing pens. During the laying period, a reduction in NPP from 0.37 to 0.09% with added phytase reduced both the manure total P and WSP by 42%. Hen-day egg production was highest on the lowest NPP diet with phytase, but fertility decreased when the dietary NPP was reduced below 0.37%. Results showed that phytase inclusion in a broiler breeder laying diet at the expense of all added P from dicalcium phosphate reduced the manure total P and WSP concentrations by 42%, with no effect on the number of chicks produced per hen housed.

Liming poultry manures to decrease soluble phosphorus and suppress the bacteria population.

Stabilizing phosphorus (P) in poultry waste to reduce P losses from manured soils is important to protect surface waters, while pathogens in manures are an emerging issue. This study was conducted to evaluate CaO and Ca(OH)2 for killing manure bacterial populations (pathogens) and stabilizing P in poultry wastes and to investigate the influence on soils following amendment with the treated wastes. Layer manure and broiler litter varying in moisture content were treated with CaO and Ca(OH)2 at rates of 2.5, 5, 10, and 15% by weight. All treated wastes were analyzed for microbial plate counts, pH, and water-soluble phosphorus (WSP), while a few selected layer manures were analyzed by phosphorus X-ray absorption near edge structure (XANES). A loamy sand and a silt loam were amended with broiler litter and layer manure treated with CaO at rates of 0, 2.5, 5, 10, and 15% and soil WSP and pH were measured at times 1, 8, and 29 d. Liming reduced bacterial populations, with greater rates of lime leading to greater reductions; for example 10% CaO applied to 20% solids broiler litter reduced the plate counts from 793,000 to 6500 mL-1. Liming also reduced the WSP in the manures by over 90% in all cases where at least 10% CaO was added. Liming the manures also reduced WSP in soils immediately following application and raised soil pH. The liming process used successfully reduced plate counts and concerns about P losses in runoff following land application of these limed products due to decreased WSP.

The effect of using different levels of tilapia by-product meal in broiler diets.

The tilapia industry has grown significantly. Much waste is generated by the industry due to the fact that only the myomere muscles are removed and sold for human consumption. This portion constitutes approximately 36% of the entire fish, leaving 64% of the fish as waste lost during the various processing operations. This waste from the tilapia processing plant has the potential of being an alternative protein source in broiler rations. The objective of this study was to measure the effect of substituting different levels of tilapia by-product meal (TBM) for soybean meal (SBM) in broiler diets. For the experiment 0, 10, 20, 30, 40, and 50% of the crude protein contributed by SBM in broiler diets was substituted with crude protein from TBM. A control and five levels of TBM were used in a corn-soybean-based diet and fed to chicks from 0 to 42 d of age. Chicks were identified and randomly allocated in a randomized complete block design. Body weight, cumulative feed consumption, feed conversion ratio, and mortality were determined on a weekly basis. At processing, carcass weights and yields were determined on a prechilled basis. Results showed that chicks fed 10, 20, and 30% TBM had significantly (P < 0.05) higher BW and feed consumption and improved feed conversion from 14 to 28 d of age compared to the other treatments. No significant differences were found for the remaining 35 and 42 d BW, feed consumption, feed conversions, mortalities, or carcass weights or yields for any of the treatments. In conclusion, the results showed that TBM could be used in broiler diets for up to 50% of the crude protein contributed by SBM.

The effect of using different levels of shrimp meal in laying hen diets.

The shrimp industry in Central America has grown significantly. Much waste is generated by this industry because of the high percentage of shrimp heads, exoskeletons, and soluble components lost during processing. The objective of this study was to measure the effect of substituting different levels of shrimp meal (SM) for soybean meal (SBM) in layer diets. A control corn-soybean layer diet and four different levels of SM substituted for SBM were fed to Single Comb White Leghorn hens from 18 to 38 wk of age. The SM replaced 0, 20, 40, 60, or 80% of SBM. The hens were housed three per cage, 30.5 cm wide x 45.7 cm deep. The five treatments were assigned randomly to three contiguous cages in each of eight rows in a randomized complete block design. Egg production was recorded daily, and feed consumption was recorded for an entire week every 21 d. Egg weight, specific gravity, and yolk pigmentation were recorded for three consecutive days every 21 d. Mortality was recorded daily. Our results showed that the different levels of SM in the diet did not significantly affect egg production. Feed consumption increased significantly (P < 0.01) only when 40 or 80% SM was used in the diet. Feed conversion was poorer for the same treatments. No significant differences were observed for mortality. Egg weights and specific gravities did not differ significantly among the treatments. Yolk pigmentation increased significantly (P < 0.001) as the levels of SM increased in the diets. In conclusion, properly processed SM can be used in relatively high levels to replace SBM in layer diets without causing detrimental effects on layer performance.

Research notes: The effect of different levels of palm kernel meal in layer diets.

Palm kernel meal (PKM), a by-product from the African Palm oil industry that is extensively cultivated in tropical countries, is an interesting feed ingredient for poultry due to its availability and low cost. The objective of this study was to evaluate the use of different levels of PKM in layer diets. This particular PKM contained 9.70% crude protein, 0.20% methionine, 0.36% lysine, and a TMEn value of 2,254 kcal/kg. A control diet based on corn and soybean meal and five different levels of PKM added to it were fed to Single Comb White Leghorn hens from 18 to 38 wk of age. The PKM levels were 0, 10, 20, 30, 40, and 50%. The hens were housed three per cage (30.5 cm wide x 45.7 cm deep). The six treatments were assigned randomly to three contiguous cages in each of eight rows in a randomized complete block design. Egg production was recorded daily, and feed consumption for an entire week was recorded every 21 d. Egg weight and specific gravity were recorded for 3 consecutive d every 21 d. Mortality was recorded daily. Results show that egg production was significantly decreased (P < 0.05) only with 50% PKM in the diet. Feed conversion was not affected by any level of PKM. Specific gravity was slightly but significantly (P < 0.05) decreased by all levels of added PKM. Feed consumption, mortality, and egg weight did not differ significantly among the treatments. We concluded that this particular PKM may be used up to 40% in the diet, taking into account that specific gravity may be slightly decreased.

The use of high oil corn in broiler diets.

We examined the effect of substituting conventional corn (CC; 3.5% crude fat) with high oil corn (HOC; 8.81 and 6.75% crude fat) on broiler performance. In Experiment 1, 100 chicks were assigned to 16 experimental pens consisting of two treatments. Treatment 1, the control group used CC, whereas in Treatment 2, CC was totally replaced with HOC containing 8.81% crude fat. In Experiment 2, 52 chicks were assigned to each of 16 experimental pens divided also into two treatments. Treatment 1 was the control group using CC and in Treatment 2 CC was totally replaced by HOC (6.75% crude fat). Body weight, cumulative feed intake, and feed efficiency were determined weekly for each pen from 7 to 42 d of age. Carcass weight and percentage yield were determined prechill. Results in Experiment 1 showed no significant differences for any parameter measured. In Experiment 2, body weight was significantly higher (P < 0.05) for birds fed HOC at 42 d of age. There were no significant differences among treatments for the remaining parameters. These results indicate that comparable performance of broilers can be obtained when CC is substituted with HOC.

Evaluation of raw and heated velvet beans (Mucuna pruriens) as feed ingredients for broilers.

Velvet bean plants (Mucuna pruriens) are used widely outside the U.S. as a cover crop. The beans (VB), high in protein, contain toxic substances that possibly can be destroyed by heating. Few data are available on the use of VB in poultry nutrition. We examined the effects of raw and dry-roasted VB on broiler performance in two experiments. In Experiment 1, 10, 20, and 30% raw VB were substituted into nutritionally balanced rations fed 0 to 42 d of age. Raw VB caused progressive reductions in growth; at 42 d of age, broilers fed 30% VB weighed 39% of controls. Feed intake declined significantly only with 30% VB. Feed efficiency decreased significantly with 20 and 30% VB. In Experiment 2, 10% raw VB and 10, 20, and 30% heated VB were fed 0 to 42 d. With 10% raw VB, broilers grew significantly slower but feed intake was unchanged. Inclusion of 10% heated VB allowed better growth than raw VB, and by 42 d of age, growth was not significantly different from that of controls. At 20 and 30%, heated VB promoted much better growth and efficiency than raw VB in Experiment 1, but values were significantly lower than those of controls. With 30% heated VB, broilers grew to 66% of control, a marked improvement over raw VB. Carcass yield was unaffected. Trypsin inhibitor activity but not L-3,4-dihydroxyphenylalanine (L-DOPA) in VB was destroyed by heating. We conclude that dry heating of VB partially destroys its growth-inhibiting factor(s), allowing successful use of 10% heated VB in broiler rations. Higher levels of heated VB reduced broiler performance, although results were much better than those of raw VB.

The effect of using different levels of shrimp meal in broiler diets.

The objective of this study was to measure the effect of substituting different levels of shrimp meal (SM) for soybean meal (SBM) in broiler diets. In Experiment 1, 0, 10, 20, 30, and 40% of the crude protein contributed by the SBM in broiler diets was substituted by crude protein from SM. In Experiment 2, 0, 60, 80, and 100% of the crude protein contributed by SBM in broiler diets was replaced by crude protein from SM. Body weight, cumulative feed consumption, and feed conversion (feed:gain) were determined on a weekly basis for 49 d in Experiment 1 and 42 d in Experiment 2. Mortality was reported daily. Carcass weight and percentage yield were determined on a prechilled basis. In Experiment 1, no significant differences were found for body weight, feed consumption, feed conversion, mortality, carcass weight, or yield. In the second experiment, body weight was found to be significantly higher (P < 0.01) at 21, 28, 35, and 42 d of age in treatments in which SM was introduced at a 100% substitution for SBM. Growth responses to SM were also seen at lower levels of substitution at 21, 28, and 35 d. No significant differences were observed for feed consumption, feed conversion, mortality, or carcass yield for any of the treatments. Carcass weight increased significantly by 12.1% when SM was substituted 100% for SBM. Results of the present study show that the particular SM used in this study could partially or totally replace SBM in broiler diets without negatively affecting performance or carcass quality.

Evaluation of early feed restriction on egg size and hen performance.

Feed restriction was implemented in a factorial design (2x4) when pullets were at either 5 or 10% egg production. Periods of feed restriction were for 0, 3, 4, or 5 d. Two trials each using 672 Hy-line W-77 White Leghorn Hens 19 wk of age were identified and randomly assigned to 16, 2x3 m pens at a density of 7 birds per square meter. Data recorded were days at sexual maturity, egg production, mortality, feed consumption, feed conversion, egg weight, body weight gain, and body weight uniformity. Hens placed on feed restriction reached sexual maturity 3 to 5 d later (P < 0.05) than the unrestricted birds. No significant main effects or interactions were found for egg production, feed consumption, feed conversion, mortality, egg weight, body weight gain, or body weight uniformity for the initial 15 wk or the entire egg production period. These results suggest that early egg size was not increased with the practice of early feed restriction nor did short- or long-term laying performance improve.

The effect of chopped computer and bond paper mixed with wood shavings as a litter material on broiler performance.

The impact of utilizing chopped computer and bond paper as a litter material on growth performance of broilers reared to market age was evaluated. In the first experiment, broilers were placed in pens at 10 birds per square meter, and four different litter treatments were used; 1) 100% chopped computer and bond paper (CCP); 2) a mix of 75% CCP and 25% wood shavings (WS); 3) 50% CCP and 50% WS; 4) 100% WS. Experiment 2 evaluated the same treatments, but with densities of 14 birds per square meter. Litter treatments had no effect on body weight gain, feed consumption, conversion, or mortality for either of the two experiments. No differences were found for percentage litter moisture among treatments. Chopped computer and bond paper alone or mixed in different percentages with WS can be used as an alternate litter material for rearing broilers as long as there is good waterer management, especially with open watering systems. These systems may have the tendency to increase the incidence of litter caking.

The effect of four levels of ascorbic acid and two levels of calcium on eggshell quality of forced-molted White Leghorn hens.

The present experiment evaluated the effect of four levels of ascorbic acid (0, 100, 250, and 500 ppm) and two levels of calcium (3.0 and 3.5%) on the productivity and eggshell quality of molted Single Comb White Leghorn hens, housed four per 30.5 cm wide x 45.7 cm deep cage. The 4 x 2 factorial treatment combinations were randomly assigned to eight blocks of cages. Egg production increased (P < .06) an average of 5% for the levels of 250 and 500 ppm ascorbic acid. No differences were observed for feed consumption, egg weight, and shell thickness for the different levels of ascorbic acid or calcium in the diet. An increase (P < .01) was observed for specific gravity, as the levels of ascorbic acid increased. Increasing the level of calcium from 3.0 to 3.5% increased (P < .01) specific gravity from 1.073 to 1.075. Shell weight increased (P < .01) with the higher levels of ascorbic acid (250 and 500 ppm). No interactions were observed between the levels of ascorbic acid and calcium. Results suggest that supplementing ascorbic acid to molted laying hens can be beneficial to egg production and eggshell quality.

Effect of number of hens per nipple waterer on the performance of several strains of layers in cages.

Two experiments were designed to study the effects of housing in cages with several hens per nipple waterer (HPN) ratios on performance of several strains of White Leghorn pullets. In Experiment 1, only body weight gain and water consumption were significantly affected by the HPN; hens at the 2:1 HPN gained more weight and consumed more water per day than those at the 4:1 HPN. The lack of a significant strain by HPN interaction indicated that the four strains responded similarly to the different HPN ratios. In Experiment 2, hens in cages with 3.5:1 and 7:1 HPN consumed significantly more water and feed than those in cages with 10:1 and 14:1 HPN. In both experiments, the HPN had no significant effect on age at sexual maturity, egg production, mortality, and egg weight, but efficiency of feed usage for egg production decreased with the 3.5:1 and 7:1 HPN.