Physical Form Of Diet Research Articles

FEEDING OF LAMBS WITH IMPROVED PELLETED FEED

The feed costs are the major expenses for the farmers and the main input that influenced the economics of livestock production. The physical form of diet is one of the main drivers for better digestibility of feed and improved growth performance of farm animals. This study aimed to evaluate the effect of using two different physical forms of diet (ground feed mixtures and pelleted feed mixtures) on the growth performance of fattening lambs. Seventy-two fattening lambs were randomly assigned to two groups with 36 fattening lambs to assess the effects of feeding with pelleted (test group) and ground feed mixtures (control group) on growth performance. Two physical forms (pelleted vs. ground) were equal in ingredient and chemical composition. The duration of the experiment was 42 days. At the beginning of the trial, the lambs in the test group had lower average live body weight and daily gain compared with the lambs in the control group. However, at the end of the feeding trial, the lambs feeding with a pelleted feed mixture had achieved a higher average live body weight and better daily gain. The results from the ANOVA for growth performance of lambs depending from the physical form of diet indicate that there was a statistically significant difference (p<0.05) between the test and control groups of lambs in the 5th and the 6th week of the feeding trial. These results support the possibility of using pelleted feeds in intensive fattening of lambs for improving the growth performance, increasing average daily gain and reducing the duration of the fattening period.

An overview about Laboratory Rodents, Digestive Physiology and Important Issues regarding Their Nutrition

The current trends in biomedical research gloabally rely upon experimental animals for their pivotal contribution in proper designs of experiments to understand the underlying mechanisms of various diseases.. These animals which are mostly rodents; are broadly preferred in biomedical research for certain characters like well established gene maps, easy adaptibility and ability to produce large number of offsprings at breeding. Besides, these animals are well known for high compliance to different diets beacuse of their characteristic digestive system structure, and high susceptibility to targeted non-infectious or genetic diseases which may cause harm to humans. Rodents are fed with different diets that meet their maintenance and productivity requirements specific to each specie and strain, highly depending upon the production or experimental purposes. Commercial diets in pellet or extruded form consisting of various feed raw materials of plant and / or animal origin, are the most widely used diets for feeding and special diets are also prepared according to the requirements of research. This review deals in comprehending the details about orgin, history, feeding behaviours and strains of variously used experimental animals. Besides, nutrient requirements of this animals; characteristics, type, content, physical form of diet and effects of environmental factors on their diet have been discussed.

Influence of the particle size and form of feed on growth performance, digestive tract traits and nutrient digestibility of white egg-laying pullets from 1 to 112 D of age.

The influence of the grinding and physical form of diets on growth performance, gastrointestinal tract (GIT) development and nutrient digestibility was studied in layer pullets from hatch to 112 d of age. Diet formed a 2 × 2 factorial with 2 hammer mill screen sizes to grind cereals (4 and 8 mm) and 2 forms (mash and crumble). A total of 864 1-day-old layer chickens were randomly assigned to 1 of the 4 treatment groups with 8 replicates (27 birds per replicate). Cumulatively, pullets fed crumbles consumed less feed (P < 0.05) and had better feed conversion ratio (FCR; P < 0.01) than those fed mash. Coarse grinding cereals (CG) improved FCR (P < 0.05) without significant change in cumulative feed consumption compared to that of fine grinding (FG). With regard to body weight gain (BWG), pullets benefited from crumbles from 1 to 56 d of age (P < 0.01). There were interactions (P < 0.05) between screen size and feed form in relation to FCR (1 to 28 d) and overall BWG. At 112 d of age, the relative weight (RW, g/100g body weight) of the crop, gizzard, pancreas, and liver of crumble-fed birds were lower (P < 0.05) than those for birds fed mash. Pullets fed coarsely ground feed had higher RW of the crop, proventriculus, gizzard, liver, and caecum compared to those fed finely ground feed. Compared to mash feeding, pullets fed crumbles increased (P < 0.05) total tract digestibility of ether extract and crude protein and the activities of pancreatic amylase and lipase. Digestibility of ether extract (P < 0.05) and pancreatic amylase activity (P < 0.01) were higher in birds fed a CG diet than in birds fed the FG regimen. Regarding the nutrition of egg-laying pullets, crumbles might be preferred to mash feed when the main objective is to improve FCR. Data also suggested that cereals used for pullet feed can be ground more coarsely than is in current practice.

Effects of processing and the physical form of diets on digestibility and the performance of nursery piglets

The aim of this study was to assess the influence of various diet processing methods and physical forms on digestibility and zootechnical performance parameters of nursery piglets. The study was performed in 2 phases. The first phase was performed twice with 120 piglets per experiment, for a total of 240 newly weaned piglets, in a randomized block design with 6 treatments and 5 replicates (30 pens). The following experimental diets were offered from weaning to 21 days after weaning (initial nursery phase) and included the following: mash diet (M); mash diet conditioned at 60ºC (CM); diet pelleted at 60ºC/matrix 2.5 mm (P2.5); diet pelleted at 60ºC/matrix 2.5 mm and crumbled (P2.5C); diet pelleted at 60ºC/matrix 4.75 mm (P4.75); and diet pelleted at 60ºC/matrix 4.75 mm and crumbled (P4.75C). The animals’ daily weight gain (DWG), daily feed intake (DFI) and feed conversion (FC) were assessed. Phase 2 used 24 piglets (33 days old) from Phase 1, which were lodged in individual metabolic cages. The experiment employed a randomized block design with 4 treatments and 6 replicates: mash diet (M); mash diet conditioned at 60ºC (CM); diet pelleted at 60ºC/matrix 2.5 mm (P2.5); and diet pelleted at 60ºC/matrix 4.75 mm (P4.75). Feces were collected to analyze the digestibility of and apparent digestible energy in dry matter, gross energy and ether extract. The processing and physical form of the diets did not affect the DWG and DFI of the 21- to 39-day-old piglets. The 2.5-mm-diameter pellets induced better FC compared to the crumbled and conditioned crumbled diets (P &lt; 0.05), which might be attributed to the better digestibility of the ether extract in the pelleted diets. Pellet size had no effect on the performance parameters.

Effects of processing and the physical form of diets on digestibility and the performance of nursery piglets

Effects of processing and the physical form of diets on digestibility and the performance of nursery piglets

The effect of the inclusion of recycled poultry bedding and the physical form of diet on the performance, ruminal fermentation, and plasma metabolites of fattening lambs.

During a 125-d experimental period, 24 Afshari × Kurdish male lambs initially weighing 25.2 ± 1.2 kg were grouped by BW and randomly assigned to treatments under a completely randomized design with a 2 × 2 factorial arrangement of treatments to evaluate the effects of feeding recycled poultry bedding (RPB; 0 and 200 g/kg DM) and the physical form of the diet (mash and block) on nutrient intake and digestibility, ruminal and plasma parameters, microbial N supply, N balance, feeding behavior, and growth performance of the lambs. Two diets with and without RPB in both mash and block form were prepared. Neither the inclusion of RPB nor the physical form of the diet affected the concentration of VFA or the total tract apparent digestibility of nutrients. Dietary RPB inclusion increased DMI ( < 0.01), tended ( = 0.10) to reduce ADG, and decreased G:F ( = 0.05). The physical form of the diet had no effect on DMI but decreased ADG ( = 0.01) and G:F ( = 0.02) in lambs fed on the block diet compared with those fed on the mash diet. Neither the inclusion of RPB nor the physical form of the diets had any effect on microbial N supply (g/d) and N retention. Rate of eating ( = 0.07), time spent eating ( = 0.87) and ruminating ( = 0.28), and total chewing activity ( = 0.65) were not affected by dietary RPB inclusion. Rate of eating decreased ( < 0.01) and time spent eating and total chewing activity increased ( = 0.01 and = 0.02, respectively) in lambs fed on the block diet compared with those fed on the mash diet. Results of the current study showed that inclusion of RPB up to 200 g/kg DM in diets for fattening was possible without any effect on performance and animal health. Processing of feed into the mash form gave higher livestock productivity in comparison to the block form.

Effect of diet grinding and pelleting fed either dry or liquid feed on dry matter and pH in the stomach of pigs and the development of gastric ulcers

The physical form of diets has a marked impact on the development of gastric ulcers in pigs. Earlier studies showed effects of fine grinding and pelleting on the integrity of gastric mucosa as well as on local intragastric milieu. This study was conducted to evaluate the effects of dry or liquid feeding on intragastric milieu (DM and pH) in pigs. The 23 piglets were housed individually and fed with test diets and water ad lib for 6 wk. Both experimental diets [coarsely ground diet fed as mash (CM) vs. finely ground pelleted diet (FP)] were identical in ingredients (39.5% wheat, 34% barley, 20% soybean meal) and chemical composition and were either offered dry or in liquid (25% DM) form. At the end of the trial the animals were slaughtered; the stomach was removed and samples were taken from different localizations. Feeding diets dry or liquid had no effect on the pH (P > 0.05). The diet noticeably affected the gastric content. The FP diets resulted in a more liquid chyme (P < 0.05), and the intragastric pH did not differ between regions. Feeding CM caused marked effects of localization regarding pH (highest values: pars nonglandularis; lowest values: fundus). None of the pigs fed CM showed signs of gastric ulcers, but the score was markedly higher (P < 0.05) when pigs were fed FP. Therefore the predominant factor for development of gastric ulcers seems to be the structure (particle size) of the diet.

Desempenho, eficiência de utilização dos nutrientes e estrutura do trato digestório de pintos de corte alimentados na fase pré-inicial com rações de diferentes formas físicas

Este estudo foi realizado com o objetivo de avaliar o efeito da forma física da ração sobre o desempenho, a utilização dos nutrientes das rações e o desenvolvimento do trato disgestório de pintos de corte na primeira semana de vida. Foram utilizados 150 pintos machos Cobb distribuídos ao acaso em três tratamentos com cinco repetições de dez aves. Os tratamentos consistiram das formas físicas farelada, triturada e peletizada de uma ração pré-inicial comercial. Com exceção da moela, os órgãos do trato digestório e a estrutura morfométrica do intestino não foram influenciados pela forma física da ração. Maior digestibilidade do N foi obtida com a ração peletizada, enquanto a ração triturada possibilitou maior digestibilidade do EE. A energia metabolizável determinada para a ração farelada foi menor que a obtida nas demais formas físicas da ração. As aves alimentadas com ração farelada tiveram menor consumo de ração e ganho de peso e pior conversão alimentar. Ingeriram ainda menos energia, apresentaram menores retenções de proteína, gordura e energia corporal e utilizaram maior proporção da energia ingerida para produção de calor. As rações pré-iniciais na forma peletizada ou triturada possibilitam maior aproveitamento dos nutrientes da ração pelos pintos e melhor desempenho.

Inclusão do ovo desidratado em rações peletizadas ou fareladas para frangos de corte

Um experimento foi realizado para estudar o efeito da forma física da ração (farelada ou peletizada) e da inclusão de ovo desidratado na ração até os 21 dias de idade sobre o desempenho e as características de carcaça de frangos de corte da linhagem Cobb-500 aos 42 dias de idade. As aves com 1 dia de vida e peso médio de 42,94 ± 0,51 g foram alojadas em boxes de 1,0 × 1,5 m. O delineamento adotado foi o inteiramente casualizado em esquema fatorial com dois níveis de ovo desidratado (0 e 0,5%) e duas formas físicas da ração (farelada e peletizada), resultando em quatro rações com 18 repetições de 16 aves durante as fases de 1 a 7; de 8 a 21; de 22 a 33 e de 34 a 42 dias de idade. A inclusão de 0,5% de ovo desidratado nas rações pré-inicial e inicial não influenciou o desempenho, porém, a ração peletizada melhorou o desempenho dos frangos de corte aos 42 dias de idade. A peletização da ração também melhorou o rendimento de peito, do Pectoralis minor e do filé de peito em relação ao peso da carcaça e aumentou os pesos do proventrículo e do intestino delgado, enquanto a ração farelada aumentou o peso da moela.

Effects of Particle Size and Physical Form of Diets on Mast Cell Numbers, Histamine, and Stem Cell Factor Concentration in the Small Intestine of Broiler Chickens

The aim of this study was to investigate the hypothesis that particle size and diet form may affect the growth of mast cells and histamine release from the small intestine of broiler chickens. A total of 288, day-old male broiler chicks were randomly allocated to 1 of 4 corn-soy diets in a 2 × 2 factorial design. The factors included particle size (coarse vs. fine) and physical form (mash vs. pellet). The birds were housed in 90 × 60 cm pens containing 12 birds, and each treatment contained 6 replicate pens of birds from d 1 to 22. On d 22, 6 broilers from each treatment were slaughtered. Tissues from the small intestine (duodenum, jejunum, and ileum) were obtained to quantify mast cells using the toluidine blue staining technique. The results showed that mast cells in the jejunum were concentrated in the upper part of the villus in birds fed the coarsely ground mash diet, whereas mast cells were evenly distributed throughout the intestine in birds fed the other 3 diets. The number of mast cells was significantly lower in the duodenum (P = 0.04), jejunum (P < 0.01), and ileum (P = 0.01) of birds fed coarsely ground diets compared with finely ground diets, and there was no difference in mast cell numbers between birds fed mashed or pelleted diets at any site in the intestine. The histamine content (P = 0.02) and stem cell factor concentration (P = 0.03) were markedly lower in the jejunum of birds that were fed coarsely ground diets compared with finely ground diets. The stem cell factor concentration in the duodenum (P < 0.01) and jejunum (P = 0.05) was higher in birds fed pelleted compared with mash diets. The overall results of this experiment suggest that particle size and diet form affect mast cell number and histamine content in the small intestine by regulation of stem cell factor concentration.

Efeito da forma física da ração sobre a porosidade, espessura da casca, perda de água e eclodibilidade em ovos de perdiz (Rhynchotus rufescens)

O objetivo do presente estudo foi avaliar se a forma física da ração (farelada e peletizada) afeta a porosidade e espessura da casca, e porcentagem de perda de água e eclodibilidade de ovos de perdiz. Os ovos foram coletados logo após a postura e separados em diferentes intervalos de peso (35-45g, 46-50g, 51-55g, 56-60g e 61-70g), sendo 10 ovos/classe/ração. O número de poros das cascas foi avaliado nas regiões apical, equatorial e basal dos ovos. Utilizou-se um micrômetro digital para a mensuração da espessura das três regiões da casca dos ovos, a partir dos quais obteve-se a espessura média por ovo. Os ovos para avaliação da eclodibilidade e porcentagem de perda de água do ovo até a transferência para o nascedouro (16º dia) foram pesados, desinfectados, incubados (T=35,5ºC e UR= 70%) e transferidos no 16º dia de incubação para o nascedouro, onde foram mantidos até a eclosão. As análises estatísticas empregadas foram: Análise de Variância e de Correlação, e teste de Tukey 5%. Os dados mostraram que, em perdizes, o número de poros na casca pode variar com a região da casca, peso do ovo e a forma física da ração, e que a ingestão de ração peletizada promove um aumento na espessura da casca dos ovos sem alterar a eclodibilidade e a porcentagem de perda de água dos mesmos durante a incubação.

High versus low protein diets to mink‐postprandial plasma urea and creatinine response, osmotic load and pattern of nitrogen and electrolyte excretion

Nitrogen balance, pattern of excretion of nitrogenous end‐products, endogenous urinary N excretion, postprandial plasma urea and creatinine, osmotic load, urinary electrolyte excretion and water intake/output relationships were studied in 12 adult female mink fed a high protein diet (HP; n=6) providing about 155g protein/kg or a low protein diet (LP; n=6) providing about 95 g protein/kg. Two balance periods of each 3 d were used and diets were fed raw or cooked. After the last balance period followed a 48 h fasting period. Postprandial plasma urea and creatinine were studied for 48 h following a test meal given after an overnight fast. Osmotic load was determined based on collection of non‐acidified urine carried out during 48h. Level of protein supply did not affect N balance, being close to zero, whereas slightly negative balances were achieved for fasting animals. Protein supply was clearly reflected in excretion of urinary urea and allantoin but not in creatinine and uric acid. Endogenous urinary N excretion was estimated by a second order regression equation giving an intercept of 280mg/kg0.75. Post‐prandial plasma urea concentrations were strongly influenced by protein supply, HP animals having substantially higher peaks than LP animals, but values returned to fasting values within 24 h after the test meal. Plasma creatinine followed a biphasic pattern with a peak about 2 h after feeding and a nadir approximately 6 h after feeding. Physical form of diet influenced postprandial urea, animals fed raw diets having a higher peak, but not creatinine. The HP diet provided almost the double osmotic load of the LP diet and a corresponding increase in urine volume. The resulting water balances were identical irrespective of diet, showing that water intake/output relationships are very accurately regulated.