C.M.C. van der Peet-Schwering

Fermented co-products and fermented compound diets for pigs: a review

This review deals with the properties of fermented diets and their effects on growth performance and gastrointestinal environment of pigs. In addition, some possible modes of action are hypothesized. Starch and sugar rich liquid co-products have a high potential for fermenting during storage. Soaking compound feed with water is another means of achieving a fermented diet. These diets are characterized by a pH between 3.5 and 4.5, high levels of lactic acid, and, to a lesser extent, acetic acid and alcohol. Fermented diets seem to improve growth performance of pigs, compared with non-fermented diets. The exact reasons for this are not yet clear; however, some hypotheses are given. Based on a limited number of studies, fermented diets reduce the gastric pH and the number of Coliform bacteria in the gastrointestinal tract compared with non-fermented diets. Furthermore, there are some indications that fermented diets may positively affect pancreatic secretion, villus architecture, digestibility and absorption of dietary nutrients. Fermented diets may reduce the physical activity of pigs. More specific studies on the effect and modes of action of fermented diets are needed to allow firmer conclusions to be drawn. # 1999 Elsevier Science B.V. All rights reserved.

Impact of feeding management on feather pecking in laying hens

In the near future EU-legislation will ban the use of conventional battery cages, while national legislation in some countries in Western Europe will ban beak trimming as well. The ban on battery cages and beak trimming causes an increased risk of feather pecking and cannibalism in laying hens. Many factors influence feather pecking behaviour, but this paper focuses on nutritional factors. Nutritional factors can have positive and negative effects on feather pecking behaviour in laying hens. Severe feather pecking has been demonstrated in birds that were fed a too low mineral level in the diet, a too low protein level or a too low amino acid level (methionine, arginine). Sometimes somewhat more feather pecking was found when layers were fed diets with mainly vegetable protein sources as compared with diets with protein from animal origin. Also more feather pecking may occur when the diets were fed restrictedly, fed coarsely ground, or fed as pellets. Feeding high-fibre diets, low energy diets, or roughages reduced feather pecking. Providing additional grain or straw in the litter during rearing could result in lower levels of feather pecking behaviour in adult stages. Some of these positive effects on feather pecking seem to be related to the time birds spend on feed intake and foraging. This paper gives an overview of the relationships between the occurrence of feather pecking behaviour and nutritional factors, such as diet composition and feeding strategies in laying hens.

Ammonia emissions from pig houses in The Netherlands, Denmark and France

In recent decades pig production has been intensified in most European countries. This has resulted in a surplus of manure and a serious concern about the effect of ammonia emissions on environmental acidification and the pollution of ground and surface water. In the Netherlands, Denmark and France approximately 50% of the ammonia emissions from pig production is from pig housing and slurry storage. Ammonia emissions from pig houses can be reduced by: (1) lowering the concentrations of urea and ammonia in the slurry; (2) lowering the temperature of the slurry; (3) reducing the emitting surface area; (4) reducing the pH of the slurry. Various housing techniques have been developed to reduce ammonia emissions. Most of these techniques are costly but cheaper systems are becoming available. A combination of housing and feeding measures seems most promising to achieve a substantial reduction in ammonia emissions at relatively low costs. Lowering the protein content of the diet, including non-starch polysaccharides and adding acidifying salts instead of CaCO3 are the main possibilities at the moment to reduce the ammonia emission by dietary means.

Environmental and legislative aspects of pig production in The Netherlands, France and Denmark

In areas of highly intensive pig production the amount of nitrogen and minerals in pig manure may far exceed the amounts of these nutrients that can be taken up by crops. Due to this imbalance, accumulation of minerals can take place and, by leaching and runoff, exceed tolerated levels of nitrate (50 mg/l), potassium (12 mg/l), and phosphate (0.15 mg Pt/l) in fresh water. This may lead to eutrophication. Air may become polluted by odours in the neighbourhood of pig farms, while ammonia emission both from pig houses and from application on the fields may be excessive. Therefore, legislation has been implemented in several countries to limit the use of pig manure per ha of land. Comparison of legislation between France, Denmark and The Netherlands show distinct differences in legislation as well as differences in the excretion of N and P in the manure from specific categories of pigs.

Nitrogen and phosphorus consumption, utilisation and losses in pig production: The Netherlands

In recent years pig production has been intensified in most European countries. This has resulted in a surplus of manure, exceeding the nutrient needs of the plants. In The Netherlands different laws have been introduced since 1984 to reduce these environmental problems. In this paper the development of pig production in The Netherlands, the environmental pollution by pigs and the policies to limit it are described. In addition, the approach in The Netherlands to reducing phosphorus and nitrogen excretion and ammonia emissions by means of nutrition is discussed. Finally, the potential and means for reducing the environmental problems in practical pig farming in the future by feeding and management measures are described.

Low Dietary Energy Concentration, High Nonstarch Polysaccharide Concentration, and Coarse Particle Sizes of Nonstarch Polysaccharides Affect the Behavior of Feather-Pecking-Prone Laying Hens

An experiment was conducted with 504 non-cage-housed ISA Brown laying hens from 18 to 40 wk of age to investigate the separate effects of dietary energy concentration, nonstarch polysaccharide (NSP) concentration, and particle sizes of added NSP source on the eating behavior, feather-pecking behavior, and hen performance of laying hens. Hens were allotted to 1 of 6 dietary treatments according to a 2 x 3 factorial arrangement, with 7 replicates per treatment. The factors were control and low energy concentration (2,825 vs. 2,540 kcal/kg), control and high NSP concentration (133 vs. 195 g/kg), and fine vs. coarse particle size of the added NSP source in the high-NSP diets. We hypothesized that eating time would be increased by feeding low-energy diets or coarsely ground, high-NSP diets, or both, resulting in reduced feather-pecking behavior, without negatively affecting hen performance. Energy reduction, NSP addition, and coarse grinding of NSP increased eating time by 14.2% (P = 0.001), 17.2% (P < 0.001), and 7.9% (P = 0.075), respectively, compared with the control level of these factors. Addition of NSP decreased eating rate (g/min) by 21.0% (P = 0.010). Layers already performed gentle feather-pecking behavior during the fifth week of the rearing period. Dietary treatments did not affect the maximal level of feather condition scores, but arise of feather damage was delayed by 10 wk in hens fed low-energy, coarsely ground, NSP-rich diets compared with hens fed control diets. Hens fed the control NSP diets showed reduced culling rates, because of less cannibalistic pecking, when energy concentration was decreased (44.1 vs. 13.1%), whereas in the high-NSP diets, culling rate decreased slightly when hens were fed the low-energy diets (31.6 vs. 28.6%; P = 0.071). Hens that were fed the low-energy diets compensated for the 10% reduction in energy concentration by a 9.3% higher maximal feed intake (143.0 vs. 130.8 g/d). Hen performance and BW gain of the hens were not affected by dietary treatments. We concluded that hens that were fed low-energy or high (coarsely ground)-NSP diets spend more time on feed intake, compared with hens that were fed the control diets. As a result, hens in some treatments showed less feather-pecking behavior.

Performance and carcass traits of individual pigs housed in groups as affected by ad libitum and restricted feeding

Abstract One hundred and eight crossbred castrated males were used to examine the effect of ad libitum and restricted feeding on performance and carcass traits of individual pigs housed in groups. The experiment included three replicates, each consisting of 36 pigs. From day 1 to 36, all pigs were given free access to feed. From day 36 to the end of the experiment, the pigs in Treatment 1 were maintained with free access to feed. For pigs in Treatments 2 and 3 the daily energy allowance per pig was restricted to 18 MJ ME above the daily energy requirement for maintenance. The weekly measured BW was used to compute the energy requirements for maintenance ( M = 0.719 MJ ME × BW(kg) 0.63 ). Daily feed intake per pig was determined by using electronic feeding stations (IVOG ® ). During the restriction period the pigs of Treatment 1 had higher total energy intake, higher energy intake for production (energy intake above maintenance), higher growth rate and higher energy conversion ratio for production than the restricted pigs. Energy conversion ratio was not affected by energy restriction. In Treatments 2 and 3 the variances of energy intake, and of energy intake for production were lower than in Treatment 1. The pigs in Treatment 2 and 3 had a 2.6 units higher lean tissue percentage in the carcass than pigs given free access to feed. It was concluded that restricting individual energy intake in group-housed castrated males can improve lean tissue percentage in the carcass.

Effect of nutrient dilution on feed intake, eating time and performance of hens in early lay

1. An experiment with 480 ISA Brown layers was conducted to measure the effect of dietary energy (11·8, 11·2 and 10·6 MJ/kg) and non-starch polysaccharides (NSP) (128, 146 and 207 g/kg) concentration, soluble NSP content (64 and 85 g/kg), particle size distribution of the NSP fraction (fine and coarse) and feed form (mash and crumble) on feed intake, eating time and egg performance of laying hens in early lay (from 18 to 26 weeks of age). Twelve experimental diets were tested, each replicated 4 times. 2. Laying hens in early lay that were fed low- or high-NSP diets were able to compensate for 10% dietary dilution by 9·5 and 4·9% higher feed intakes, respectively. Feeding crumble or coarsely ground mash did not affect feed intake. 3. Eating time of the hens fed the undiluted diets increased over the experimental period from 16·4 to 24·6% of the observation period, but was not affected by sand or grit addition, particle size distribution or feed form. Feeding high-NSP diets increased eating time by 22%. 4. Egg performance and body weight gain of the hens that were fed low-NSP or high-NSP diets were similar or better compared to the undiluted diets, whereas coarse grinding of the diets showed 7 to 10% lower egg performance and weight gain. Egg performance and weight gain were not affected by feed form. 5. It is concluded that hens in early lay, fed energy-diluted diets, by adding sand or grit (low-NSP) or NSP-rich raw materials (high-NSP) to the control diet, were able to increase their feed intake, resulting in energy intake and egg performance comparable to the control group. Supplementing diets with insoluble NSP also decreased eating rate. Prolonged eating time using insoluble NSP could be useful in reducing feather pecking behaviour.

Development of stereotypic behaviour in sows fed a starch diet or a non-starch polysaccharide diet during gestation and lactation over two parities

The effect of feeding sows a starch diet or a diet with a high level of fermentable non-starch polysaccharides (NSP) during gestation, lactation or both gestation and lactation over the first two parities on the development of stereotypic behaviour was studied in sows housed in groups during gestation and individually during lactation. A total of 119 postpubertal gilts were allotted to a 2 x 2 factorial experiment. Treatments were diet composition during gestation (G-Starch: 274 g/kg starch and 123 g/kg fermentable NSP or G-NSP: 86 g/kg starch and 300 g/kg fermentable NSP) and diet composition during lactation (L-Starch: 293 g/kg starch and 113 g/kg fermentable NSP or L-NSP: 189 g/kg starch and 216 g/kg fermentable NSP). Sows on both gestation diets were fed iso-energetic. During lactation, sows were given free access to the lactation diets. Behavioural measurements were carried out in weeks 3, 12 and 15 after start of the experiment or after weaning in parity 1 and 2 sows, respectively, 3 days before the expected date of parturition and 1 week before weaning in the first 3 h after the morning meal using a scan-sampling technique. Feeding group-housed sows a diet high in fermentable NSP during gestation reduced the frequency of total non-feeding oral activities (=sham chewing + other non-feeding oral activities) in gestation compared with a starch diet (P <0.001 and

A review of sow and piglet behaviour and performance in group housing systems for lactating sows.

Commercial use of group housing systems for lactating sows is limited, but the recent transition to group housing during gestation in the EU may result in a renewed interest in such systems. Therefore, this review aims to identify key factors that may contribute to the success or failure of group housing of lactating sows in comparison with individual housing by describing the variety in group housing systems and discussing animal behaviour and performance compared with individual housing. Group housing systems can be divided in multi-suckling (MS) systems, in which sows are grouped with their litters, and get-away (GA) systems, which include a separate communal area accessible to sows only. These systems differ in many aspects regarding management and layout but, compared with individual housing, generally provide more environmental complexity, more freedom of movement for the sows and more freedom to express behaviours related to, for example, maternal care and social interactions. Group housing poses several risks, such as disrupted nursing and an increased level of crushing during the MS phase, and in the GA systems there is a risk for early cessation of nursing. On the other hand, pre-weaning mingling of litters clearly benefits piglet social development and may improve adaptation to the post-weaning situation. In addition, group-housed sows may show lactational ovulation, which provides opportunities for insemination during an extended lactation period, which benefits the piglets. Gradual transitions in social and physical environment around gestation, farrowing, grouping and weaning seem to be key success factors for group housing systems during lactation. In addition, selection of suitable sows and quality of stockmanship seem important.