Feed Trough Research Articles

Effects of castration on eating pattern and physical activity of Holstein bulls fed high-concentrate rations under commercial conditions1

A total of 132 animals (initial BW = 220 ± 22 kg and age = 166 ± 0.4 d) were used to study the effect of castration on eating behavior and physical activity. Animals were randomly allocated to 6 pens with 2 pens for each of the 3 treatment groups: 44 intact bulls, 44 steers castrated (3 mo of age) before the study began, and 44 bulls castrated (CAS) at 8 mo of age (at d 69 of the study). The study finished when animals reached 292 d of age. Each pen held 22 animals, and had 1 computerized concentrate feeder (GEA WestfaliaSurge, Germany), 1 feed trough for straw, and 1 water source. Concentrate and straw were offered ad libitum. Animals were weighed every 14 d and eating pattern at which animals consumed concentrate was averaged for each 14-d period. A pedometer was placed on the left hind leg of 86 animals randomly distributed among treatments to estimate physical activity from d -5 to 10 relative to surgical castration (d 65 to 79 of study). The statistical model included initial BW as a covariate, treatment, period, and the interaction between treatment and time (14-d), as fixed effects, and pen and animal as random effects. For physical activity data, day was the repeated measure. The CAS animals exhibited reduced ADG and concentrate DMI (P < 0.001) during the first 2 wk after castration than bulls or steers. Eating behavior throughout the study differed among treatments. Meal size (1.3 ± 0.05 kg) and meal duration (12.4 ± 0.47 min) were greater (P < 0.001) in bulls during the 2 wk after castration than in steers (1.0 ± 0.05 kg and 9.7 ± 0.46 min, respectively) and CAS animals (0.8 ± 0.05 kg and 7.8 ± 0.47 min, respectively). In contrast, bulls visited the feeders less frequently (5.3 ± 0.34/d) during these 2 wk than did steers (6.7 ± 0.34/d) and CAS animals (7.7 ± 0.34/d). In addition, daily intake, meal size, and eating rate increased (P < 0.001) with time. Lying time in CAS animals was reduced (P < 0.001) for the 5 d after castration compared with bulls and steers. Bulls were more active (steps/h) than steers, and activity of recently castrated animals decreased (P < 0.001) for at least 10 d after castration. Although 2 wk after castration differences in eating pattern across treatments were observed, the long-term effects of castration and gender (bull vs. steer) on eating behavior were difficult to interpret. Castration effects on total feed intake and lying time are temporary, whereas castration has a lasting reduction on physical activity.

Effect of hygiene and medication on preweaning survival and growth of Djallonké sheep in Atacora, Benin

Low sheep productivity in North Benin hampers economic development, and improvement can contribute to reduction of rural poverty and food insecurity. To reduce one of the constraints to the productivity of Djallonké sheep, high mortality during suckling in full rainy and start dry season, we tested hygienic measures and medication in improved housing. The effect of the two treatments and their combination on lamb performance and the internal rate of return (IRR) were compared to a control. For each treatment, survival and growth were observed in 20 lambs, living in 38 herds. Good housing and hygiene (daily cleaning and fortnightly disinfection of stable and water and feed troughs) reduced mortality and increased growth of suckling lambs until 3 months. Good housing plus medication (unique injection of vitamins and amino acids and with ivermectine for deworming, weekly tick treatment by spraying, and in case of diarrhea, antibiotic treatment) reduced mortality, but growth was not higher than the control. Accounting labor opportunity, the IRR was about equal for both, but capital investment was lower for the hygiene treatment which is thus more accessible to poor farmers. The combination of both treatments increased growth and benefits compared with the hygiene treatment, but decreased the IRR.

Dietary self-selection by broilers at normal and high temperature changes feed intake behavior, nutrient intake, and performance

Self-selection assumes that at high ambient temperature, birds are able to select a diet from different sources to minimize the heat load associated with the ingested nutrient metabolism. The objective was to test the hypothesis that young chickens are able to compose an adequate ration by adjusting dietary nutrient intake from 3 different diets that vary in energy and in protein contents from a cafeteria system at high temperature (HT; 31–32°C) and at normal temperature (NT; 31–21°C). Night temperature was set at 25°C at HT and at 18°C at NT and 12 h dark:12 h light. Control birds were fed a standard control diet (CP: 215 g/kg; ME: 2,895 kcal/kg) for broiler chickens. The choice-fed birds could choose between the control diet, a high-protein diet (CP: 299 g/kg; ME: 2,780 kcal/kg), and a high-energy diet (CP: 150.7 g/kg; ME: 3,241 kcal/kg). The diets had similar pellet size and color. Birds had access to each diet in a separate feeding trough from 1 to 42 d of age. Results showed that broilers spent 3.3% more time eating at NT than at HT and showed 42% more panting behavior at HT than at NT. High temperature decreased feed intake, protein intake, energy intake, and BW gain. Choice-fed birds had similar feed intake and BW gain, 14% lower protein intake, and 6.4% higher energy intake than control-fed birds. Body temperature and heterophil/lymphocyte ratio were higher at HT than at NT. Water intake was 8% higher in control-fed birds than in choice-fed birds but similar at both temperature regimens. It can be concluded that broilers can compose a diet by selecting less protein but higher energy density from different diets compared with the control. Choice-fed birds had similar feed efficiency as control-fed birds at HT, indicating similar body composition for both groups. Extra energy intake of choice-fed birds at HT was used for panting activity.

Effect of mothering on the spatial exploratory behavior of quail chicks

Previous maternal deprivation experiments demonstrated that absence of maternal care impacts the behavioral development of young animals. Here we assessed the influence of the presence of a mothering hen on the spatial exploration of Japanese quail chicks, after the mothering period. Brooded and nonbrooded chicks were placed in a novel environment containing feeding troughs. The distribution of chicks and their inter-individual distances were measured during repeated tests. Brooded chicks exhibited a higher ability to disperse, thereby progressively exploiting larger surfaces and gaining access to food more easily. The fact that exploration by nonbrooded chicks was delayed suggests a deficit in their exploratory motivation and/or spatial skills. We hypothesize that brooded chicks experienced the constraint to follow the mothering hen, and to adapt to frequent reconfigurations of their environment. The lack of this variability in the environment of nonbrooded chicks could have reduced adaptability of their spatial behavior.

Laying Performance of Wareng Chicken under Free Choice Feeding and Different Cage Density

The aim of the experiment was to explore the possibility of using free choice feeding technique under different cage density for unselected native chicken. Eighty hens of laying Wareng chicken were divided into two feeding systems. Half of them were fed complete commercial diet of 17% crude protein, with 2800 kcal ME/kg and the other half were subjected to free choice diet. The diets were in mash form and placed in sufficient feed troughs in front of each cage. Each cage was occupied by four or six hens. Free choice feeding hens were served with commercial concentrate (30% crude protein), ground corn and oyster shell, placed separately in feed troughs. Observation was carried out during 24 weeks laying period, starting from 20 to 44 weeks of age. The results showed that egg production (9.35% hen day), and the intake of feed (42.74 g/day), protein (7.01 g/day), energy (116.6 kcal ME/day), calcium (1.99 g/day and phosphorus (0.22 g/day) were not affected (P&gt;0.05) by feeding system nor by cage density. The results however indicated that free choice feeding technique provided sufficient nutrients in supporting maximum egg production of unselected native chicken.

Influence of Strain of Chickens on Ileal Amino Acids Digestibility of Different Protein Sources

The main objective of this study was to assess the nutritional value of four protein sources (soyabean meal, fish silage, sardine fish and fishmeal) using commercial broiler and local poultry strains. Four experimental diets were formulated; representing four different proteins sources and was evaluated using six replicates of eight birds per cage at 21 day of age. Cages were located in an environmentally controlled room maintained under conditions suitable for birds at this age with a photo-period of 23 h in every 24 h. Diets and water were offered on ad libitum basis. On the fourth day after the adaptation to th e experimental diets, feed troughs were removed from every cage for 1 h and then reintroduced for 2 h. Then the birds were killed to allow for sampling of ileal digesta, from Meckel's diverticulum to the ileal-caecal- colonic injunction. Broiler birds showed significantly (p<0.001) higher digestibility coefficients and digestible content of amino acids across all the protein sources than the local birds. Out of the four protein sources evaluated in this study, fishmeal had the lowest amino acids digestibility coefficient for the two bird breeds (p<0.001). The digestibility coefficient and digestible content of amino acids estimates for fish silage was the highest across the two strains (p<0.001). The lower digestibility of amino acids for soyabean meal is related to the presence of; antinutritional factor, trypsin inhibitor. Fish silage shows a great potential to be used as protein supplements for poultry feeding. The results suggest that the class of chickens and protein source significantly influenced the apparent ileal digestibility and digestible contents of amino acids in the nutrient assessed in this study.

Ammonia and greenhouse gas emission from group-housed gestating sows depends on floor type

The ban by 2013 in the EU of individual accommodations for gestating sows and the renewed interest for litter systems could promote in the future the group-housing of gestating sows on litter. But what are the environmental impacts of this rearing technique? To answer this question, a study was scheduled to quantify pollutant gas emissions (nitrous oxide –N 2O–, methane –CH 4–, carbon dioxide –CO 2– and ammonia –NH 3–) according to floor type in the raising of group-housed gestating sows. The trial was carried out in experimental rooms located at Liège University (Belgium). Three successive batches of 10 gestating sows were used for this trial. Each batch was divided into 2 homogeneous groups randomly allocated to one of two treatments: concrete slatted floor or straw-based deep litter. The groups were kept separately in two identical rooms equipped with a pen divided into a lying area (slatted floor or deep litter) and five individual feeding stalls. The feeding stalls were equipped with front feeding troughs and rear gates preventing access to the stalls outside of the feeding time. Between each batch of sows, the pens were cleaned. In both rooms, ventilation was automatically adapted to maintain a constant ambient temperature. The gas emissions were measured 3 times (weeks 2, 5 and 8 of stay) during 6 consecutive days by infra red photoacoustic detection. Sow performance (body weight gain, backfat thickness, number and weight of piglets) was not significantly affected by floor type. With sows kept on slatted floor, gaseous emissions were significantly greater for NH 3 (12.77 vs. 9.05 g d −1 sow −1; P < 0.001) and CH 4 (10.12 vs. 9.20 g d −1 sow −1; P < 0.01), and significantly lower for N 2O (0.47 vs. 2.27 g d −1 sow −1; P < 0.001), CO 2 equivalents (0.44 vs. 0.94 kg d −1 sow −1; P < 0.001) and CO 2 (2.41 vs. 2.83 kg d −1 sow −1; P < 0.001) compared to sows housed on straw-based deep litter. There was no significant difference for water vapour emissions (3.25 vs. 3.21 kg d −1 sow −1; P > 0.05). In conclusion, the main environmental disadvantage of the deep litter system pointed to in this study was the greater N 2O-emissions and thus greater CO 2eq-emissions compared to slatted floor. However, the use of deep litter was related to reduced NH 3- and CH 4-emissions.

The effect of feed trough position on choice of defecation area in farrowing pens by loose sows

The primary aim of the present study was to investigate how the feed trough position affects the sow's choice of defecation area in a loose house farrowing pen. The eliminative behaviour of 24 1st parity sows was studied in a cross-over design. The feed trough and the water were positioned either in the activity area towards the neighbouring pen or in the activity area towards the aisle. On day 15 after farrowing, the feed trough and the water were moved to the opposite position. Videotapes were observed continuously on real time and the time of urination or defecation were recorded along with head and hindquarter positions in the period of days 7–14 and in the period of days 21–28 after farrowing. The feed trough position had a significant effect ( P < 0.001) on sow head position when eliminating. Sows preferred the head to be located as far away from the resting area and the feed trough as possible when eliminating. For the hindquarter position, there was a significant effect ( P < 0.001) of feed trough position on the number of observations that the hindquarter was over the slatted area when eliminating. A confounding effect could be that the sow's hindquarter position was influenced by a partition wall placed in one end of the pen. No significant difference was found between observations periods on frequency of urination or defecation. The results demonstrate the importance of design of farrowing pens for loose housed sows to ensure that the sow eliminate in the designated areas.

The role of starlings in the spread of Salmonella within concentrated animal feeding operations

Summary 1. Characterizing and mitigating the disease risks associated with wildlife use of concentrated animal feeding operations (CAFOs) can reduce the spread of micro‐organisms throughout the environment while increasing agricultural productivity. To better understand the disease risks associated with bird use of CAFOs, we assessed the capacity of European starlings Sturnus vulgaris to spread Salmonella enterica to cattle, their feed and water. 2. We sampled starlings, cattle feed, cattle water and cattle faeces from 10 CAFOs in Texas, USA. Samples were screened for Salmonella enterica to investigate: (i) the prevalence of S. enterica in starlings using CAFOs, (ii) whether there was a relationship between cattle infections and starling numbers, and (iii) if S. enterica contamination of cattle feed and water was related to numbers of starlings observed on CAFOs. 3. We used generalized linear mixed logistic regression models to assess the importance of starlings, cattle stocking, facility management and environmental variables in the transmission of S. enterica to cattle, feed troughs and water troughs in CAFOs. 4. Starling gastrointestinal tract samples tested positive for S. enterica (2·5% prevalence; 95% CI = 0·3%, 8·6%) and starlings were retained as model covariates in the best supported logistic regression models for S. enterica contamination within cattle feed, water and faeces. 5. Salmonella enterica contamination of both cattle feed troughs and water troughs is significantly related to numbers of starlings. Contamination in cattle feed increased as more starlings entered feed troughs. Contamination in water troughs increased asymptotically as numbers of starlings on CAFOs increased. Starling variables in the cattle faecal shedding model were not significant. 6. Synthesis and applications. The numbers of European starlings better explained S. enterica contamination of cattle feed and water than other variables including cattle stocking, facility management and environmental variables. This suggests that starlings are a source of S. enterica contamination in CAFOs. Thus, starling management tools such as population control, habitat management, exclusionary devises and bird repellents may be used to reduce the amplification and spread of disease within livestock production systems.

Epidemiology of Eimeria and associated risk factors in cattle of district Toba Tek Singh, Pakistan

A cross-sectional study was carried out to determine the prevalence, species characterization, and associated risk factors with Eimeria of cattle of district Toba Tek Singh from April, 2009 to March, 2010. Of the total 584 fecal samples examined for Eimeria, 275 (47.09%) were found infected with six species of Eimeria. Among the identified species of Eimeria, Eimeria bovis was found to be the highest prevalent species (52.36%), followed in order by Eimeria zuernii, Eimeria canadensis, Eimeria ellipsoidalis, Eimeria alabamensis, and Eimeria cylindrica with prevalence of 48.27%, 34.83%, 29.31%, 24.14%, and 8.62% respectively. Peak prevalence was observed in August. Cattle were infected more frequently during rainy (60.32%) and post-rainy seasons (59.25%). Calves had significantly higher prevalence (P<0.05) of Eimeria than adults while higher prevalence of Eimeria was observed in female cattle. Among management and husbandry practices, feeding system, watering system, housing system, floor type, and herd size strongly influenced the prevalence of Eimeria in cattle. Coccidiosis was more prevalent in ground feeding system, pond-watered animals, closed housing system, and non-cemented floor type (P<0.05) as compared to trough feeding system, tap watered animals, open housing system, and partially cemented floor types, respectively. Breed and body condition of animals were not found risk factors (P>0.05) influencing prevalence of Eimeria.

A high dose of monensin does not reduce methane emissions of dairy cows offered pasture supplemented with grain

The primary objective of our research was to determine the effect of a high dose of monensin supplementation on enteric CH4 emissions of dairy cows offered a ryegrass pasture diet supplemented with grain. An additional objective was to evaluate effects on milk production and rumen function, because a commensurate improvement in milk production could lead to adoption of monensin as a profitable strategy for methane abatement. Two experiments were conducted (grazing and respiratory chambers) and in both experiments monensin (471mg/d) was topdressed on 4kg (dry matter)/d of rolled barley grain offered in a feed trough twice daily at milking times. In the grazing experiment, 50 Holstein-Friesian cows were assigned randomly to 1 of 2 groups (control or monensin). Cows grazed together as a single herd on a predominantly ryegrass sward and received monensin over a 12-wk period, during which time measurements of milk production and body weight change were made. The SF6 tracer technique was used to estimate methane production of 30 of the 50 cows (15 control cows and 15 monensin cows) for 3 consecutive days in wk 3, 5, 8, and 12 of treatment. Samples of rumen fluid were collected per fistula from 8 of the 50 cows (4 per diet) on 2 consecutive days in wk 3, 5, 8, and 12 of treatment and analyzed for volatile fatty acids and ammonia-N. In the metabolic chamber experiment, 10 pairs of lactating dairy cows (control and monensin) were used to determine the effects of monensin on methane emissions, dry matter intake, milk production, and body weight change over a 10-wk period. Methane emissions were measured by placing cows in respiration chambers for 2 d at wk 5 and 10 of treatment. Cows received fresh ryegrass pasture harvested daily. Monensin did not affect methane production in either the grazing experiment (g/d, g/kg of milk) or the chamber experiment (g/d, g/kg of dry matter intake, g/kg of milk). In both experiments, milk production did not increase with addition of monensin to the diet. Monensin had no effect on body weight changes in either experiment. Monensin did not affect volatile fatty acids or ammonia-N in rumen fluid, but the acetate to propionate ratio tended to decrease. Monensin did not improve milk production of grazing dairy cows and no effect on enteric methane emissions was observed, indicating that monensin cannot be promoted as a viable mitigation strategy for dairy cows grazing ryegrass pasture supplemented with grain.

From product manufacturing to engineering services

One of the main directions of diversification at BKO JSC is manufacturing products for the glass industry. Aside from the production of the conventional aluminosilicate refractories, BKO JSC develops and produces new types of refractory materials, performs preliminary bench assembly of the structural elements of furnaces (bottom, loading-hopper arch, subchecker arch, feeder troughs). Specialists at BKO JSC provide engineering services for designing individual units of a glassmaking furnace using the BKO’s materials. All design solutions are accompanied by recommendations for performing the lining work and putting linings into the working regime.

Effects of environmental enrichment and loose housing of lactating sows on piglet performance before and after weaning1

We investigated effects of loose housing of the sow during lactation and enrichment of the pen pre- and postweaning on performance of newly weaned piglets. Before weaning, piglets (n = 320) were housed in an enriched (straw, wood shavings, peat, and branches) or barren pen with a confined or loose-housed sow (n = 32). Loose-housed sows and their piglets could eat together from a family feeder, whereas confined sows and piglets had separate feeding troughs. Piglets (n = 256) were mixed postweaning, and 4 piglets from each litter were relocated to a barren pen (n = 32 pens) and 4 other piglets were housed in an enriched pen (n = 32 pens). Growth from d 15 until weaning was greater for piglets from enriched pens (4.38 ± 0.29 vs. 4.71 ± 0.21 kg/pig, P < 0.05) and tended to be greater for piglets with a loose-housed sow compared with piglets with a confined sow (4.41 ± 0.26 vs. 4.67 ± 0.24 kg/pig, P = 0.10). Preweaning feed intake was not affected by preweaning conditions (P > 0.25). Piglets from enriched preweaning pens ate more in the first 2 d postweaning than piglets from barren pens (first 48 h, barren 0.45 ± 0.05 kg/pig, enriched 0.53 ± 0.04 kg/pig, P < 0.05). Piglets relocated to an enriched pen after weaning showed a greater growth in the 2 wk after weaning (barren 5.5 ± 0.2 kg/pig, enriched 6.2 ± 0.2 kg/pig, P < 0.0001), had a profoundly reduced diarrhea prevalence than piglets housed in barren pens after weaning (barren 2.4 ± 0.4 d, enriched 1.0 ± 0.3 d, P < 0.0001), and had a greater feed efficiency (barren 0.81 ± 0.03, enriched 0.85 ± 0.02, P < 0.05). Enrichment of the preweaning environment likely stimulates development of feeding behaviors and consequently increases feed intake immediately after weaning. Providing piglets with an enriched environment after weaning positively affected postweaning growth, feed efficiency, and incidence of diarrhea, which may be caused by decreased stress or increased gut health. Enrichment of the pre- and postweaning environment seems important in improving performance and health of newly weaned pigs.

Supplementation with whole cottonseed causes long-term reduction of methane emissions from lactating dairy cows offered a forage and cereal grain diet

The objective of our work was to supplement a forage and cereal diet of lactating dairy cows with whole cottonseed (WCS) for 12 wk and to determine whether the expected reduction in CH4 would persist. A secondary objective was to determine the effect of supplementing the diet with WCS on milk yield and rumen function over the 12-wk feeding period. Fifty lactating cows were randomly allocated to 1 of 2 diets (control or WCS). The 2 separate groups were each offered, on average, 4.2kg of DM/cow per day of alfalfa hay (a.m.) and 6.6kg of DM/cow per day of ryegrass silage (p.m.) on the ground in bare paddocks each day for 12 wk. Cows in each group were also individually offered dietary supplements for 12 wk in a feed trough at milking times of 5.4kg of DM/cow per day of cracked wheat grain and 0.5kg of DM/cow per day of cottonseed meal (control) or 2.8kg of DM/cow per day of cracked wheat grain and 2.61kg of DM/cow per day of WCS. The 2 diets were formulated to be similar in their concentrations of CP and ME, but the WCS diet was designed to have a higher fat concentration. Samples of rumen fluid were collected per fistula from the rumen approximately 4h after grain feeding in the morning. Samples were taken from 8 cows (4 cows/diet) on 2 consecutive days in wk 2 of the covariate and wk 3, 6, 10, and 12 of treatment and analyzed for volatile fatty acids, ammonia-N, methanogens, and protozoa. The reduction in CH4 emissions (g/d) because of WCS supplementation increased from 13% in wk 3 to 23% in wk 12 of treatment. Similarly, the reduction in CH4 emissions (g/kg of DMI) increased from 5.1% in wk 3 to 14.5% in wk 12 of treatment. It was calculated that the average reduction in CH4 emissions over the 12-wk period was 2.9% less CH4 per 1% added fat, increasing from 1.5% in wk 3 to 4.4% less CH4 in wk 12. There was no effect of WCS supplementation on rumen ammonia-N, rumen volatile fatty acids, rumen methanogens, and rumen protozoa. On average over the 12-wk period, supplementation with WCS decreased the yield of milk (10%), fat (11%), protein (14%), lactose (11%), and fat plus protein (12%) and BW gain (31%). The WCS supplementation had no effect on milk fat concentration but resulted in a decrease in concentration of protein (5%) and lactose (11%). The major finding from this study is that addition of WCS to the diet of lactating dairy cows resulted in a persistent reduction in CH4 emissions (g of CH4/kg of DMI) over a 12-wk period and that these reductions in CH4 are consistent with previous work that has studied the addition of oilseeds to ruminant diets.

Apparent Ileal Amino Acids Digestibility of Four Varieties of Barley for Two Strains of Chickens

The main objective of this study was to assess the nutritional value of four varieties of barley (Beecher, Jimah 54, Jimah 51 and Jimah 58) using commercial broiler and local poultry strains. Four experimental diets were formulated, representing four different varieties of barley and were evaluated using six replicates of eight birds per cage at 21 day of age. Cages were located in an environmentally controlled room maintained under conditions suitable for birds at this age with a photo-period of 23 h in every 24 h. Diets and water were offered on ad libitum basis. On the fourth day after the adaptation to the experimental diets, feed troughs were removed from every cage for 1 h and then reintroduced for 2 h. Then the birds were killed to allow for sampling of ileal digesta, from Meckel’s diverticulum to the ileal-caecal-colonic injunction. Broiler birds showed significantly (p<0.001) higher digestibility coefficients and digestible content of amino acids across all the barley varieties than the local birds. Out of the four barley varieties evaluated in this study, Beecher variety had the lowest amino acids digestibility coefficient and digestible content for the two bird breeds (p<0.001). The digestibility coefficient and digestible content of amino acids estimates for Jimah 54 was the highest across the two strains (p<0.001). The variability in digestibility and digestible content in barley varieties can be attributed to the high fiber levels and the presence of beta-glucan. The results suggest that the class of chickens and variety significantly influenced the apparent ileal digestibility and digestible contents of amino acids in the nutrient assessed in this study.

The effects of feeder space and adjustment on growth performance of finishing pigs (2010)

A total of 288 pigs (PIC TR4 x 1050, initially 82 lb) were used in a 91-d study to evaluate the effects of feeder trough space (1.75 vs. 3.5 in/pig) and minimum feeder-gap opening of 0.5 in. (narrow), vs. 1.0 in. (wide) on finisher pig performance. Our hypothesis was that at minimal feeder trough space (1.75 in./pig), feeders should be set at a wide gap opening to avoid limiting feed intake and ADG. The feeders were adjusted to the minimum gap setting, but the agitation plate could be moved upward to a maximum gap opening of 0.75 in. or 1.25 in., respectively. The treatments were arranged in a 2 x 2 factorial with 6 replications per treatment. All pens had the same feeder with 2, 14-in.-wide by 4.5-in.-deep feeder holes. Feeder trough space was adjusted by placing 8 or 16 pigs per pen. Gating was adjusted to give each pig 8 ft2 of floor space. Pigs had ad libitum access to feed and water. All pigs were fed a corn-soybean meal-based diet containing 20% dried distillers grains with solubles (DDGS) in 4 phases. Pen weights and feed disappearance were measured every 2 wk. Narrow-adjusted feeders averaged approximately 48% coverage, and wide-adjusted feeders averaged approximately 85% coverage. Overall (d 0 to 91) there were no trough space x feeder adjustment interactions observed (P > 0.10). However, there was a tendency (P = 0.08) for increased ADG as feeder trough space increased from 1.75 to 3.5 in./pig. Pigs fed with the wide feeder-gap setting had increased (P < 0.01) feed disappearance and poorer (P < 0.01) F/G compared to pigs with the narrow feeder-gap setting. These results suggest that, regardless of feeder trough space, pigs with the wide feeder adjustment appeared to waste more feed, as evidenced by the poorer F/G.; Swine Day, Manhattan, KS, November 18, 2010

Nitrous oxide emissions from small-scale farmland features of UK livestock farming systems

Nitrous oxide (N 2O) fluxes were measured from small-scale farmland features which are not explicitly accounted for when compiling greenhouse gas inventories for livestock farming systems. These included poached land surrounding feeding and water troughs, seepage from liquid and solid manures, gateways, tracks and ditches. Measurements were made on two dairy and two beef-and-sheep farms with contrasting soil types located in the southwest of England, UK. High temporal and spatial variability of N 2O fluxes were observed. Some features were persistent hotspots of N 2O emission, and fluxes from all features were predominantly higher than those measured from adjacent pasture. Seepage areas from liquid manures and poached land around water troughs produced the highest N 2O fluxes with maximum emissions of 288 kg N 2O ha −1 yr −1 and 212 kg N 2O ha −1 yr −1, respectively. The main soil property influencing N 2O fluxes was nitrate concentration. The spatial extents of the features relative to the whole farms were small and therefore, despite the high fluxes measured from them, their contribution to the whole farm flux generally was not significant. However, on one farm the emissions from the farmland features were 14.3% of the IPCC estimated total farm flux, suggesting that current methodology could, on occasion, be underestimating N 2O emissions from livestock farms.

Light intensity and social communication between hens

1. The effect of light intensity on social communication in laying hens was investigated experimentally by comparing the transmission and detection of social signals between familiar and unfamiliar hens of similar or unequal rank in a competition for food. 2. The experimental method consisted of mutual inspection by a pair of hens at short range (approximately 24 cm), followed by a competition at a feed trough from which only one hen could eat a favoured food. The relative rank of a hen was inferred from success in this competition. 3. The relative rank of individual hens within 5 groups, each of 6 adult laying hens, was determined to identify those of high and low rank within their home group. 4 Social communication between pairs of either unfamiliar or familiar hens of either similar or unequal rank (highest and lowest ranking within their home groups) was then assessed under light intensities of 1, 5, 20 and 100 lux with all other cues present. Only the dimmest light of 1 lux perturbed some aspects of the competition for food. 5. The findings provide scientific justification, in part, for the current legal requirement in England for ‘all hens to see other hens’ by specifying a minimum light intensity of at least 5 lux for hens kept in close proximity to each other.

The effect of feeder space allocation on productivity and physiology of Hy-Line W-36 hens housed in conventional cages

Insufficient feeder space for laying hens could increase competition at the feed trough, leading to disrupted feeding, inadequate nutrient intake, stress, and reduced productivity. The effects of feeder space allocation (FSA) on physiology and productivity were evaluated in beak-trimmed Hy-Line W-36 hens (n = 480). They were obtained at 16.5 wk of age and housed on 4 tiers of shallow conventional cages. Five pullets/cage were housed at a stocking density of 434 cm2/hen and a feeder space of 12.2 cm/hen. After 1.5 wk of acclimation, baseline measurements were taken for feed utilization, bone mineralization, and heterophil:lymphocyte ratios. At 20 wk of age, pullets were given 5.8, 7.1, 8.4, 9.7, 10.9, or 12.2 cm of feeder space/bird (16 cages/treatment). Physiological and production measures were calculated monthly or twice a month for 12 mo. The heart, spleen, and right adrenal gland were collected from each hen at the end of the study. Data were analyzed using a repeated measures GLM incorporating cage, tier, FSA, and hen age. There were no effects of FSA on total egg production, bone mineral density, bone mineral content, heterophil:lymphocyte ratios, or organ weights. Hens with reduced FSA utilized more feed (P < 0.001), had poorer feed conversion (P < 0.001), and laid eggs with slightly thicker and heavier shells (P < 0.001). There were effects of FSA on total egg weight (P < 0.001) and hen-day egg production (P < 0.001), but they were of low magnitude and not linear (P > 0.05). Because BW was similar among FSA treatments, the results suggest that reduced feeder space did not limit feed intake. In addition, reduced FSA did not lower bone mineralization or cause physiological stress in W-36 hens housed in shallow cages, suggesting that it did not impair hen welfare. However, it did result in poorer feed efficiency, possibly related to greater feed wastage, predictive of an adverse economic effect from reducing feeder space.

The effect of feeder space allocation on behavior of Hy-Line W-36 hens housed in conventional cages

Insufficient feeder space for laying hens could increase competition at the feed trough, resulting in exclusion of low-ranking hens from the feeder. To test this hypothesis, the effects of feeder space allocation (FSA) on feeding behavior, aggression, feather scores, BW, and mortality were evaluated in a common commercial strain of egg-laying chickens. Beak-trimmed Hy-Line W-36 hens (n = 480) were obtained as pullets at 16.5 wk of age and housed in conventional cages on 4 tiers. Five pullets/cage were housed at a stocking density of 434 cm2/pullet and an FSA of 12.2 cm/pullet. After 1.5 wk of acclimation, baseline measurements were taken for 2 wk and then pullets were given either 5.8, 7.1, 8.4, 9.7, 10.9, or 12.2 cm of feeder space/hen (16 cages/treatment). Feeding behavior was evaluated in each cage over a 24-h period each month. For each hen, percentage of time spent feeding and synchrony (mean number of additional hens feeding at the same time) were determined and scores were averaged for each cage. For each cage, feeder switching (number of observations in which hens changed from feeding to not feeding) and feeder sharing (probability that feeder access was equally distributed among all hens) were calculated. At monthly intervals, individual hens were weighed and their feathers scored using a 5-point scale on 8 body regions. Data were analyzed using a repeated measures GLM incorporating cage, tier, FSA, and age of the hen. Hens with reduced feeder space spent less time feeding (P < 0.001), synchronized their feeding bouts to a lesser extent (P < 0.001), made fewer switches at the feeder (P < 0.001), and shared the feeder less (P < 0.001). However, feather scores, BW, and BW uniformity were not affected by FSA. There was almost no aggressive behavior and little mortality. These results demonstrate that Hy-Line W-36 hens did not respond to reduced feeder space by aggressively excluding cage-mates from the feeder but instead desynchronized their feeding behavior.