Litter Moisture Research Articles

Performance, meat quality and fatty acid profile of broiler chickens fed mixed semi-purified glycerin

The aim of the present study was to evaluate the effects of the inclusion of mixed (animal and vegetable sources) semi-purified glycerin (MSPG) in broiler diets on performance, litter moisture, serum glycerol concentration, carcass and parts yields, meat quality, and the fatty acid profile. In total, 576 1-day-old male Cobb 500 broiler chicks were distributed in a completely randomised design into four treatments (0%, 2.5%, 5.0% and 7.5% dietary inclusion levels of MSPG, as-fed basis), with six replicate pens of 24 birds each. The apparent metabolisable energy corrected for nitrogen balance and energy metabolisability coefficient values of the MSPG were 12.33 MJ/kg DM and 81.61% respectively. There was no significant (P > 0.05) effect of the MSPG concentration on the performance, and carcass and parts yields or broiler meat-quality variables, except for thigh meat colour, in which the yellowness value (b*) decreased linearly (P < 0.05) with an increasing inclusion level of MSPG. Litter moisture and serum glycerol increased linearly (P < 0.05) and the lipid profile of the thigh and drumstick meat of broilers at 42 days of age was slightly altered (P < 0.05) with an increasing MSPG. Mixed semi-purified glycerin can be used at up to 7.5% in broiler diets without impairing performance, meat quality, carcass and parts yields from 1 to 42 days of age. However, special attention should be paid to litter moisture.

Effectiveness of poultry litter amendments on bacterial survival and Eimeria oocyst sporulation.

Aim:Broilers’ optimum performance in response to their genetic potential depends on litter environment which is ideal for bacterial survival and coccidian oocyst sporulation. An in vitro evaluation was conducted for the effectiveness of superphosphate, meta-bisulfide, and charcoal litter amendments in minimizing Escherichia coli O157:H7 and Salmonella Typhimurium survival, Eimeria oocyst count, and sporulation.Materials and Methods:Three groups of 16 litter trays were prepared and inoculated with E. coli O157:H7, S. Typhimurium, and Eimeria non-sporulated oocyst. A set of four trays in each group was designed for each one of the chemical amendments. A total of 720 litter samples were collected and examined for bacterial counts, Eimeria oocyst count, and sporulation during the experimental period (35 days).Results:Litter moisture and pH revealed a highly significant (p<0.001) reduction in all treated litter trays compared to control. Total bacterial count (TBC), total Enterobacteriaceae count, and S. Typhimurium count showed a highly significant (p<0.001) reduction in meta-bisulfide-treated trays compared to other amendments and positive control. Meanwhile, Eimeria oocyst count and sporulation revealed a highly significant (p<0.001) reduction in superphosphate, meta-bisulfide, and charcoal-treated trays, respectively. Temperature revealed a highly significant (p<0.001) weak positive correlation with pH of all inoculated trays, a highly significant (p<0.001) weak negative correlation with moisture percentage of E. coli O157:H7 and S. Typhimurium inoculated trays, and a highly significant (p<0.001) weak negative correlation with TBC. Meanwhile, relative humidity revealed significant (p≤0.005) weak positive correlation with moisture percentage of E. coli O157:H7 inoculated trays.Conclusion:The study concluded that regular usage with periodical reapplication of litter amendments as meta-bisulfide or superphosphate in poultry farms is one of the indispensable managemental and preventive measures for minimizing bacterial survival and inhibiting Eimeria oocyst maturation and sporulation.

The Short-Term Effects of Experimental Forestry Treatments on Site Conditions in an Oak–Hornbeam Forest

Forest management alters forest site; however, information is still limited about how different silvicultural treatments modify abiotic conditions. We compared the effects of four treatments from three different forestry systems on forest microclimate, litter, and soil conditions. The clear-cutting, retention tree group, preparation cutting, and gap-cutting treatments were experimentally established in a European oak-dominated forest, following a complete block design with six replicates. In this study, we show the results of the quantitative analyses of 21 variables, one year after the interventions. Strong treatment effects were observed for the microclimate and litter variables, whereas the soil characteristics remained similar. The increase in light was the highest in the clear-cuts with intermediate effects in the gap-cuts. The means and variances of the air and soil temperature as well as the vapor pressure deficit were the highest for the clear-cutting treatment. An increase in soil moisture, litter pH, and litter moisture was significant in the gap-cuts and, to a smaller extent, in the clear-cuts. The soil pH increased in the retention tree groups. Microclimatic differences between the treatments were the largest during the summer, which demonstrates the buffering effect of the canopy. Our study confirms that less intensive and more spatially heterogeneous silvicultural treatments (e.g., gap-cutting) preserve a stable below-canopy microclimate more effectively. These results can support and might be useful for both forest management and conservation planning.

Moisture content estimation of forest litter based on remote sensing data.

As a fine fuel, forest litter plays an important role in fire danger rating systems, so forest litter moisture data are necessary and meaningful for fire risk management and prevention. An optical remote sensing technique can provide continuous and regional data for litter moisture estimates, but such an approach is restricted in separating the background reflectance of the forest floor from pixel reflectance because the litter moisture information is included only in background reflectance while pixel reflectance in the forest area consists of both canopy reflectance and background reflectance. Therefore, we present a geometrical-optical model to estimate forest litter moisture by separating contributions of background reflectance from the remote sensing image and use a statistical model to estimate the forest litter moisture content based on the calculated background reflectance. The results show that the model had an R2, root mean square error (RMSE), and average precision of 0.595, 0.372, and 69.654%, respectively. This approach provides a new way of estimating forest litter moisture content from an optical remote sensing image, and it can potentially be applied in large-scale forest litter moisture content mapping.

Effect of litter density and foot health program on ammonia emissions in broiler chickens

SUMMARY The effect of litter density and addition of organic minerals (Availa-Zn® and Mn®) and Yucca schidigera extract (MicroAid®) on ammonia emissions in broiler chickens was evaluated. Four treatments were tested: I. Traditional growing program with a litter density of one kg m−2 of rice hulls (TP1); II. Treatment I with a litter density of 2 kg m−2 of rice hulls (TP2); III. Traditional growing program with a foot health program (40 ppm of Availa-Zn®, 40 ppm of Mn®, and 125 ppm of MicroAid®) during the growing cycle with a litter density of one kg m−2 of rice hulls (TP1+FHP); and IV. Treatment III with a litter density of 2 kg m−2 of rice hulls (TP2+FHP). Ross-line chickens were used. Ammonia emissions from litter and at peak height (ppm), litter moisture (%), relative humidity (%), pH, litter temperature (°C), and ambient temperature (°C) were measured weekly during the growing period. The results of ammonia emissions from litter showed significant differences among treatments (P ≤ 0.0001); treatments with a litter density of 2 kg m−2 plus the use of organic minerals and MicroAid® added separately and in combination were statistically different from the traditional program (TP1), reducing ammonia emissions from litter by up to 36%.

Higher rates of decomposition in standing vs. surface litter in a Mediterranean ecosystem during the dry and the wet seasons

Plant litter decomposition in drylands is not well understood, and even less is known about decay of the abundant standing dead residues. Here, we followed decomposition of standing and surface litter, and assessed the underlying drivers and mechanisms. In a field experiment during contrasting seasons, litterbags were suspended at 0.05 and 1 m above ground (standing litter) and were placed on the ground (surface litter). We also quantified the moisture content of free-standing litter. During nighttime in the dry, rainless season, minimum temperature was 2–3 °C lower in standing litter, leading to higher litter moisture and a doubling of microbially-driven CO2 emissions from standing compared with surface litter. Free-standing litter moisture increased linearly with height to almost 2 m above ground. Ultimately, mass loss was higher in standing than in surface litter during the dry season (11–12% vs. 7%) and over both the dry and the wet seasons (27–34% vs. 23%), and was positively related to potentially active microbial biomass. Our results suggest that standing litter decomposed faster than surface litter because of enhanced microbial degradation, and possibly photodegradation, all-year-round. Therefore, carbon turnover in drylands and beyond may be underestimated by only considering surface litter decay.

Performance study of White Pekin ducks in different stocking density in floor rearing system

To study the effect of different stocking density on the performance of White Pekin ducks, 144 unsexed day-old White Pekin ducklings were reared for 42 days and on 43rd day, these duckings were distributed into four equal groups, each with three replicates in deep litter system of rearing. The floor space provided per ducking was G1 : 1,350 cm2, G2 : 1,800 cm2 , G3 : 2,250 cm2 and G4 : 2,700 cm2. The experiment continued from 7-10th weeks of age. The parameters studied were body weight, body weight gain, feed consumption, feed conversion ratio (FCR), serum biochemical profile, carcass characteristics and litter moisture content. The 7th and 8th week body weight gain of all the treated groups did not differ significantly but higher body weight of ducks were recorded in G3 and G4 groups than that of G1 and G2 groups at 9th and 10th week of age. The cumulative (7-10 weeks) body weight gain and FCR of white Pekin ducks was higher in group G3 and G4 than that of G1 and G2 groups. Cumulative feed consumption of all the treated groups of ducks did not differ significantly. No significant difference was observed in the studied serum biochemical and carcass characteristics of the treated groups. The litter moisture content was lower in G3 and G4 than that of G1 and G2 groups in all the studied periods. From this, it may be concluded that the floor space of 1,350 cm2 up to 8th week and 2,250 cm2 at 9th and 10th weeks of age per Pekin duck is suitable with respect to production performance of birds.

Modeling surface fuels moisture content in Pinus brutia stands

Fuel moisture content is an important variable for forest fires because it affects fuel ignition and fire behavior. In order to accurately predict fuel ignition potential, fuel moisture content must be assessed by evaluating fire spread, fireline intensity and fuel consumption. Our objective here is to model moisture content of surface fuels in normally stocked Calabrian pine (Pinus brutia Ten.) stands in relation to weather conditions, namely temperature, relative humidity, and wind speed in the Mugla province of Turkey. All surface fuels were categorized according to diameter classes and fuel types. Six fuel categories were defined: these were 0–0.3, 0.3–0.6, and 0.6–1 cm diameter classes, and cone, surface litter, and duff. Plastic containers 15 × 20 cm in size with 1 × 1 mm mesh size were used. Samples were taken from 09:00 to 19:00 h and weighed every 2 h with 0.01 g precision for 10 days in August. At the end of the study, samples were taken to the laboratory, oven-dried at 105 °C for 24 h and weighed to obtain fuel-moisture contents. Weather measurements were taken from a fully automated weather station set up at the study site prior to the study. Correlation and regression analyses were carried out and models were developed to predict fuel moisture contents for desorption and adsorption phase for each fuel type categories. Practical fuel moisture prediction models were developed for dry period. Models were developed that performed well with reasonable accuracy, explaining up to 92 and 95.6% of the variability in fuel-moisture contents for desorption and adsorption phases, respectively. Validation of the models were conducted using an independent data set and known fuel moisture prediction models. The predictive power of the models was satisfactory with mean absolute error values being 1.48 and 1.02 for desorption and adsorption as compared to the 2.05 and 1.60 values for the Van Wagner’s hourly litter moisture content prediction model. Results obtained in this study will be invaluable for fire management planning and modeling.

Broiler production without antibiotics: United States field perspectives

Recent United States Food and Drug Administration restrictions on antibiotic use in broilers should have minimal impacts on broiler health and performance. Of more significance are marketing programs that more severely restrict and often totally prohibit the use of antibiotics, including ionophores, in broiler production. The major impacts of antibiotic-free programs include increased neonatal infections due to removal of added antibiotics from Marek’s vaccines, compromised control of coccidiosis and necrotic enteritis, control of litter moisture and the issues associated with wet litter, and general disease control. Management of these issues requires significant adjustments to management and diet and the use of non-antibiotic medications such as chemically-synthesized coccidiostats. While these adjustments can ameliorate the impacts of antibiotic-free programs, performance, health, and welfare problems are likely to exceed those found in programs with unrestricted access to judicious use of all approved medications.

Why did severe feather pecking and cannibalism outbreaks occur? An unintended case study while investigating the effects of forage and stress on pullets during rearing

This 2 × 2 factorial experiment aimed to investigate the effects of stimulating foraging behavior from wk 6 and imposed stress at wk 16 on the development of severe feather pecking (SFP) in chickens reared for free-range egg production. Non-beak-trimmed ISA Brown chicks were purchased at one day old and floor-reared on wood shavings. From wk 6, straw was provided daily in dispensers (Forage vs. No forage) to stimulate foraging. At wk 15, there were 16 pens of 50 pullets. “Stressors” were applied to half the pens in wk 16 via combined transport, relocation, and mixing (TRM) of pullets, simulating activities around transfer from the rearing to egg-laying farm (TRM vs. Not TRM). Range access was permitted from wk 21. Behavior, plumage damage (PD), growth, egg production, feed use, injuries, and mortalities were recorded, along with litter moisture and pH. In wk 26, an SFP outbreak commenced. By wk 34, PD was worse in south- than north-aspect pens (P < 0.001). Further, PD was more affected by side of the shed than the experimental treatments. In wk 30, an outbreak of injurious pecking (IP) commenced in the 4 TRM-treatment pens on the south side, with IP deaths almost 3 times more common in the Forage+TRM than No forage+TRM treatment. We suggest factors associated with a 13-day rainfall event that occurred in late winter predisposed the flock to SFP. While multiple factors such as winter cold, muddy ranges, damp floor litter with elevated pH, among others coincided, hens were clearly more impacted in south- than north-aspect pens. Once initiated, SFP possibly spread via social learning, and by wk 40, ∼98% of hens had PD. Interestingly, the IP outbreak was related to a combination of factors (stressors?), such as being housed in colder, damper south-aspect pens (note: southern hemisphere), having added Forage, and TRM. These unexpected relationships could help direct future research to identify the specific factors involved in the causation of SFP and IP/cannibalism outbreaks.

Effects of stocking density and string provision on welfare-related measures in commercial broiler chickens in windowed houses

Lower stocking densities (SD) are sometimes used in windowed houses for broilers as part of systems designed to produce high-welfare products. However, there is little scientific information on the effects of SD on welfare-related measures in broilers in windowed houses, and on whether these effects are influenced by environmental enrichment. Commercial windowed broiler chicken houses were assigned to 4 target SD (30, 32, 34, and 36 kg/m2) and 2 levels of access to string [+S (one piece per 1,000 birds/house), -S] in a 4 × 2 factorial arrangement. Treatments were applied in one of 4 houses on each of 2 farms, and replicated over 10 production cycles. Levels of lying behavior, apparent fear-related behavior, and gait score were observed in wk 3 to 5. The incidence and severity of dermatitis lesions were assessed at d 30 and at slaughter. Environmental and production performance parameters also were measured. No significant treatment effects were obtained for levels of lying or fear-related behavior, final body weight, presence of dermatitis lesions at slaughter, or percentage of downgraded carcasses. There were no significant treatment effects on measures of gait, but the percentage of birds with a gait score of ≥2 tended to increase at higher SD. The severity of dermatitis lesions at d 30 increased with increasing SD, and was significantly greater at densities of 34 and 36 kg/m2 than of 30 kg/m2. Litter moisture content was not significantly affected by treatment, which may have reflected a numerical decline in water consumption with increasing SD. Results suggest that increasing SD is a risk factor for more severe dermatitis; however, increasing density from 30 to 32 kg/m2 did not significantly affect this variable. In addition, the proportion of lame birds, levels of lying behavior, and performance were not significantly affected by increasing SD. Providing suspended string at typical commercial levels did not have beneficial effects on welfare-related measures, and further research should perhaps investigate effects of greater levels of provision.

Body growth, intestinal morphology and microflora of quail on diets supplemented with micronised wheat fibre

ABSTRACT1. Particle size reductions of fibre-rich materials alter structure, functional and digestive properties. To determine the effects of using fibre as an additive in Japanese quail rations on performance and gut physiology, a trial using micronised wheat fibre (MWF) at levels of 0.0, 5, 10 and 15 g/kg in feed was conducted.2. Growth rate and feed efficiency were significantly improved when diets contained MWF while feed intake was not affected by levels of the fibre. As MWF content increased, the relative weight of gizzard and gastrointestinal tract (GIT) significantly increased whereas liver relative weight significantly decreased.3. MWF inclusion significantly increased relative length of gut segments, villi height, villus thickness, the villi height to crypt depth proportion in jejunum and ileum and the number of goblet cells in different parts of intestine.4. Tibia weight, length and ash content were increased linearly with rising MWF inclusion. Litter moisture was affected by MWF inclusions in a quadratic manner. The colony forming unit (CFU/g) of Streptococci spp. in ileal digesta was decreased with increasing MWF inclusion levels in the diet.5. In conclusion, MWF can be used as a feed additive in quail diets and its inclusion in feed resulted in better performance, beneficial changes in intestinal microbial counts and improvements in small intestine morphology.

Litter moisture adsorption is tied to tissue structure, chemistry, and energy concentration

AbstractThe ability of plant litter to adsorb water is important for wildland fire, hydrological, and biogeochemical processes. Variation in water adsorption has largely been attributed to physical differences across species, with the role of litter chemistry in moisture dynamics receiving little attention. We hypothesized that lower specific leaf area (SLA, cm2/g) and higher concentrations of hydrophobic lignin and lipid biomolecules would be associated with decreased litter water adsorption. Because plant biochemistry is tied to litter elemental and structural traits via biophysics and leaf economics, we expected to observe a suite of linked traits that were related to water adsorption, including element concentrations, carbon oxidation state, and energy concentration (ΔHc). In litter from 22 species, we observed greater than fourfold variation in the maximum amount of liquid water adsorbed (adsorption capacity, g/g) and in the rate at which dry litter adsorbed water vapor (adsorption rate, mg g−1 min−1); there was a significant positive relationship between adsorption capacity and adsorption rate. Broadly, litter with low SLA had a low carbon oxidation state, low oxygen and ash concentrations, and high concentrations of carbon, hydrogen, lignin, and lipids. The two metrics of water adsorption had significant negative relationships with concentrations of energy, lignin, carbon, and hydrogen, and positive relationships with litter SLA and carbon oxidation state. However, water adsorption was better predicted by combinations of SLA with chemical and energy traits. Several traits associated with decreased litter water adsorption, such as concentrations of lignin and energy, also directly influence some of the same ecosystem processes affected by litter moisture (e.g., decomposition, wildland fires). In particular, because plants with the hydrophobic traits identified in this study are more abundant in dry environments, our observations suggest a mechanism that could accentuate the influence of litter traits on ecosystem processes and which merits further research. Understanding the role of these traits in water adsorption could be used to help predict shifts in ecosystem function as plant communities reassemble as result of climate change as well as provide quantitative information on how plant species influence wildland fire dynamics.

Protein fermentation in the gut; implications for intestinal dysfunction in humans, pigs, and poultry.

The amount of dietary protein is associated with intestinal disease in different vertebrate species. In humans, this is exemplified by the association between high-protein intake and fermentation metabolite concentrations in patients with inflammatory bowel disease. In production animals, dietary protein intake is associated with postweaning diarrhea in piglets and with the occurrence of wet litter in poultry. The underlying mechanisms by which dietary protein contributes to intestinal problems remain largely unknown. Fermentation of undigested protein in the hindgut results in formation of fermentation products including short-chain fatty acids, branched-chain fatty acids, ammonia, phenolic and indolic compounds, biogenic amines, hydrogen sulfide, and nitric oxide. Here, we review the mechanisms by which these metabolites may cause intestinal disease. Studies addressing how different metabolites induce epithelial damage rely mainly on cell culture studies and occasionally on mice or rat models. Often, contrasting results were reported. The direct relevance of such studies for human, pig, and poultry gut health is therefore questionable and does not suffice for the development of interventions to improve gut health. We discuss a roadmap to improve our understanding of gut metabolites and microbial species associated with intestinal health in humans and production animals and to determine whether these metabolite/bacterial networks cause epithelial damage. The outcomes of these studies will dictate proof-of-principle studies to eliminate specific metabolites and or bacterial strains and will provide the basis for interventions aiming to improve gut health.

Eco-hydrological controls on microclimate and surface fuel evaporation in complex terrain

The micrometeorological factors driving variation in litter moisture (GWClit) at the landscape scale are poorly understood, particularly in areas with heterogeneous vegetation and complex terrain. In this research we seek to quantify how climate and eco-hydrology contribute to variation in litter moisture and potential evaporation at the forest floor. Research sites were established at 12 locations in southeast Australia with variable precipitation, solar exposure, and drainage position. We measured solar radiation, air temperature, relative humidity, litter moisture, and litter temperature. Spatial patterns of GWClit, examined during two drying phases, show that moisture in the litter and its rate of evaporation are closely linked to vegetation density, which is largely a function of aridity. This creates a pattern whereby aridity-related differences in vegetation structure controls the spatial variation in GWClit, with regional effects being driven by precipitation while local effects are caused by variation in solar exposure and drainage position. By parametrising a model of daily potential evaporation (Ep) at the forest floor we explore how vegetation and topography influence evaporative demand above the litter layer. The model shows that Ep is driven primarily by net radiation and that the role of vapour pressure deficit is almost negligible due to high moisture content within the sub-canopy air mass and high aerodynamic resistance. In dry forests the net radiation is directly related to shortwave radiation and Ep remains high despite low temperatures. In the tall wet forests, commonly found at high elevations, along drainage lines and on slopes with polar-facing aspects, the long-wave radiation (i.e. temperature) was just as important for Ep as the shortwave radiation. Low energy inputs to the forest floor in these tall forests means that a significant rainfall event results in surface fuels that remain wet for much longer than fuels in the dry open forest. This leads to a spatial pattern of flammability whereby surface fuels in densely vegetated areas are more often less likely to burn than those in the open forests. These wet compartments limit landscape-scale fire activity by creating dis-connectedness in the available fuel. Heatwaves and the duration of dry spells determine the degree with which these wet compartments persist as barriers to fuel connectivity through a fire season. Elsewhere in the landscape, however, the large inputs of shortwave radiation to the forest floor means that surface fuels reach flammable conditions within several hours or days after rainfall and are therefore flammable for much of the fire season.

Soya bean meal increases litter moisture and foot pad dermatitis in maize and wheat based diets for turkeys but maize and non-soya diets lower body weight

ABSTRACT1. A 2 × 2 factorial experiment was conducted to compare the effects of wheat or maize based diets differing in dietary electrolyte balance (DEB) on litter moisture and foot pad dermatitis (FPD) at 4, 8 and 12 weeks of age in heavy-medium turkeys. A second objective was to investigate the effects on foot pad dermatitis of the interaction between dietary composition and artificially increasing litter moisture by adding water to the litter.2. High DEB diets contained soya as the main protein source whereas low DEB diets did not contain soya bean meal. Diets were formulated to be iso-caloric and iso-nitrogenous in each of 3 successive 4-week phases following recommended dietary compositions. DEB concentrations were 330, 290 and 250 mEq/kg in high DEB diets and 230, 200 and 180 mEq/kg in low DEB diets.3. Litter moisture and mean FPD score were higher in turkeys fed on high DEB diets compared with low DEB diets whereas there was no difference between maize and wheat.4. Food intake was similar and body weight was lower after litter moisture was artificially raised in the wet compared with the dry litter treatment and there was no interaction with dietary composition.5. Mean body weight and feed intake were higher in turkeys fed on wheat compared with maize and in high DEB compared with low DEB diets at 12 weeks of age.6. Lowering dietary DEB for turkeys may improve litter moisture and lower the prevalence of FPD in commercial turkey flocks.

The effects of a reduced balanced protein diet on litter moisture, pododermatitis and feather condition of female broiler breeders over three generations

Protein content reduction in broiler breeder diets has been increasingly investigated. However, broiler breeders reared on low protein diets are characterized by a deterioration of the feather condition. Furthermore, polydipsia induced by controlled feed intake increases litter moisture and as a consequence pododermatitis. This project aimed to study the litter moisture, pododermatitis and feather condition of breeders fed with a 25% reduced balanced protein (RP) diet during the rearing and laying period over three successive generations. The experiment started with two treatments for the F0 generation: control (C) group fed with standard C diets and RP group fed with RP diets. The female F0-progeny of each treatment was divided into the two dietary treatments as well, resulting in four treatments for the F1 generation: C/C, C/RP, RP/C and RP/RP (breeder feed in F0/F1 generation). The RP diet fed breeders received on average 10% more feed than C diet fed breeders to achieve the same target BW. The female F1-progeny of each treatment were all fed with C diets which resulted in four treatments for the F2 generation: C/C/C, C/RP/C, RP/C/C and RP/RP/C (breeder feed in F0/F1/F2 generation). Litter moisture, footpad and hock dermatitis were recorded at regular intervals throughout the experimental period in all three generations. For the F0 and F1 generation, the pens of breeders receiving C diets had significantly higher litter moisture than the RP diets fed groups (P<0.05), resulting in an elevated footpad dermatitis occurrence (FDO) (P<0.05). No difference was found in the F2 generation. The feather condition was scored during the laying period for each generation. F0 and F1 breeders reared on the RP diets had poorer feather condition than those receiving the C diets (P<0.05). The C/RP breeders had a significantly poorer feather condition than RP/RP breeders (P<0.05). For the F2 generation, RP/RP/C breeders had a significantly better feather condition compared with the other three groups (P<0.05). The RP/C/C breeders were significantly better feathered than C/C/C breeders (P<0.05). In conclusion, providing RP diets to broiler breeders improved litter condition and hence reduced FDO whereas impaired feather condition. Furthermore, positive transgenerational effects of the maternal RP diets on the feather condition may be inferred, hence potentially altering the welfare status.

Mesophytic litter dampens flammability in fire‐excluded pyrophytic oak–hickory woodlands

AbstractFire exclusion in eastern North AmericanQuercus–Caryawoodlands has resulted in overstory compositional changes, linked to altered fuel composition, structure, and ultimately, altered fire regimes. These compositional changes have been implicated in a dampening effect on fire behavior in formerly fire‐prone ecosystems, the positive feedback termed “mesophication.” Several proposed mechanisms are likely involved in this process; however, few have been examined. We evaluated the potential mechanism of dampened forest floor flammability through changes in litter composition in a southeastern U.S. oak–hickory forest undergoing mesophication. Laboratory drying and burning experiments revealed that increasing the relative contribution of litter from fire‐sensitive mesophytic tree species (Liquidambar styraciflua,Ulmus alata, andCornus florida) increased moisture retention and diminished litter flammability. Litterbeds composed of ≥66% mesophyte litter gained the most moisture following fuelbed saturation and were consistently wetter than pyrophyte litter following 12 and 24 h of drying. Flammability metrics decreased with increasing contribution of mesophyte litter with reductions most pronounced under more moist conditions. Under dry conditions, where litter moisture did not differ across compositional treatments, mesophyte litter was less flammable than fuelbeds that contained any pyrophyte litter. The combined effects of moisture retention and less flammable litter reveal an important synergistic impact that may result with increased dominance of fire‐sensitive mesophytic species. Restoration efforts in long‐unburned eastern hardwood forests may require altering stand composition to limit mesophytic litter input or developing burn prescriptions that intensify surface fire behavior in less flammable fuels.

Performance of broiler chickens reared at two stocking densities and coir litter with different height

ABSTRACT The objective of this study was to evaluate the performance of broiler chickens reared at two stocking densities and coir litter with different height. A total of 522 one-day male chicks were distributed in a completely randomized design in a 3×2 factorial arrangement, with three litter height (5, 10 and 15 cm) and two densities (10 and 13 birds/m2), with six triplicates. The experimental period lasted 42 days, evaluating pH and litter moisture; performance; carcass traits; bone quality; and intensities of breast, hock and footpad lesions in the birds. Regarding the effect of density, a significant influence was observed only on performance, wherein the birds reared at the density of 13 birds/m2 showed lower intake and weight gain and better feed conversion than those reared at the density of 10 birds/m2. Irrespective of the rearing density and litter height, the hock and footpad lesions were frequent, and with severe intensity. It is concluded that coir with 5 cm height can be used to housing up to 13 birds/m2; however, the high rate of hock and footpad lesions makes the use of coir in the evaluated form unfeasible.

Litter quality of broiler fed with to different levels of sulfur amino acid

The objective of this study was to determine the effect of sulfur amino acid (methionine+cystine) supplementation included in the diet of broiler chickens raised under Brazilian commercial conditions on the concentration of ammonia gas, moisture, pH, temperature, and nitrogen excretion in litter on the 14th, 28th, and 42nd day of breeding. A total of 900 male chicks of the Cobb500 line were used, distributed in a completely randomized design with five treatments, with six replicates of 30 birds. A basal diet (without methionine) was formulated and was supplemented with DL-methionine (0.072, 0.168, 0.239, 0.311% and 0.058, 0.134, 0.192, 0.250% for days 1 to 21 and days 22 to 42 of breeding respectively) replacing the corn starch in order to achieve the desirable digestible methionine + cysteine levels (0.545 (basal diet), 0.616, 0.711, 0.782 and 0.853%) and (0.514 (basal diet); 0.571; 0.647; 0.704 and 0.761% and digestible methionine + cysteine for the phase 1 to 21 and 22 to 42 days of breeding, respectively. There was no significant effect on the temperature and concentration of ammonia gas in any of the phases evaluated. Met+cys supplementation influenced moisture and pH of litter in all the evaluated phases. For nitrogen, a significant effect was observed at 14 days, not exhibiting effects during the other phases, suggesting that nitrogen excretion increases with increasing levels of met+cys in the diet for up to 14 days.