Metabolizable Energy Levels Research Articles

Effects of dietary metabolizable energy level on hepatic lipid metabolism and cecal microbiota in aged laying hens

Lipid metabolic capacity, feed utilization, and the diversity of gut microbiota are reduced in the late laying stage for laying hens. This experiment aimed to investigate the effects of different levels of dietary metabolizable energy (ME) on hepatic lipid metabolism and cecal microbiota in late laying hens. The 216 Peking Pink laying hens (57-wk-old) were randomly assigned to experimental diets of 11.56 (HM = high ME), 11.14 (MM = medium ME), or 10.72 (LM = low ME) MJ of ME/kg, with each dietary treatment containing 6 replicates per group and 12 chickens per replicate. The HM group showed higher triglyceride (TG), total cholesterol (T-CHO), and low-density lipoprotein cholesterol (LDL-C) concentrations in the liver compared with the LM group; second, the HM group showed higher TG concentration and the LM group showed lower T-CHO concentration compared with MM group; finally, the HM group showed a lower hepatic lipase (HL) activity compared with the MM and LM groups (P < 0.05). There was a significant difference in the microbial community structure of the cecum between the HM and MM groups (P < 0.05). The decrease of dietary ME level resulted in a gradual decrease relative abundance of Proteobacteria. At the genus level, beneficial bacteria were significantly enriched in the LM group compared to the MM group, including Faecalibacterium, Lactobacillus, and Bifidobacterium, (linear discriminant analysis [LDA] >2, P <0.05). In addition, at the species level, Lactobacillus crispatus, Parabacteroides gordonii, Blautia caecimuris, and Lactobacillus johnsonii were significantly enriched in the LM group (LDA>2, P < 0.05). The HM group had a higher abundance of Sutterella spp. compared to the LM group (LDA>2, P <0.05). In conclusion, this research suggests that the reduction in dietary energy level did not adversely affect glycolipid metabolism or low dietary ME (10.72 MJ/kg). The findings can be helpful for maintaining intestinal homeostasis and increasing benefit for gut microbiota in late laying hens.

12 Effects of increasing SID lysine (Lys) and metabolizable energy (ME) levels of lactation diets fed to young and multiparous sows

Abstract Providing insufficient lysine to lactating sows can reduce piglet performance and subsequent farrowing performance of sows. Current SID lysine and ME recommendations for lactating sows are approximately 60 g/d and 20 Mcal/d, respectively. Because of variations in feed intake during lactation, a portion of sows do not meet recommended Lys intake levels. There is no clear understanding of the Lys:Calorie ratio when dietary energy is increased in the summer to ensure adequate caloric intake. The objective was to evaluate a potential advantage of feeding diets with SID Lys and energy levels that exceed recommendations to lactating sows. A total of 855 sows were fed during the summer of 2023 in 2×2 factorial arrangement of treatments in a randomized complete block design. Factors included SID lysine [low (0.85%) vs high (1.11%)] and ME [low (3,183 kcal/kg) vs high (3,334 kcal/kg)]. Diets were formulated to deliver 61 g of SID lysine at 0.85% inclusion to sows that consume 7.2 kg of complete feed per day. Primary outcome variables were sow body composition, lactation average daily feed intake (ADFI), average piglet weaning weight, and pre-wean mortality. There were no interactions between treatments (P &amp;gt; 0.05). SID Lys intake was 61.2 and 76.4 g/d for low and high Lys, respectively (P &amp;lt; 0.01). ME intake was 21.9 and 23.4 Mcal/d for low and high energy, respectively (P &amp;lt; 0.01). Contrary to expectations, ADFI did not differ (P = 0.25) between sows fed the low- and high-energy diets, however, sows fed low lysine consumed 0.29 kg more feed (P &amp;lt; 0.01) per day compared with sows fed high lysine. There were no differences (P ≥ 0.70) in the number of piglets born alive for any treatment group. Sows fed high energy had 0.27 fewer (P &amp;lt; 0.01) still-born piglets per litter compared with sows fed low energy. Pre-wean mortality was also reduced (P = 0.05) by 0.76 percentage units in litters of sows fed the high-energy diet compared with litters of sows fed the low energy. Lysine level had no effects on farrowing and litter performance (P &amp;gt; 0.05). Litters from sows fed the high-energy diet gained 1.2 kg more (P = 0.05) body weight during lactation and tended to result in litter-weaned weights that were 1.5 kg heavier (P = 0.06) than litters from sows fed the low-energy diet. Feeding a diet with a greater lysine concentration during lactation reduced feed intake but did not affect litter performance. In contrast, increasing dietary energy immediately before farrowing and during lactation did not affect sow feed intake but reduced pre-wean mortality and resulted in fewer still-born piglets, greater litter gains, and heavier litter weaning weights.

Analysis of current equine feeding practices in the Netherlands and identification of potential nutrient leaching and environmental contamination factors

The aim of this study was to estimate the potential for nutrient leaching based on current feeding practices of horses in the Netherlands. An online survey of horse owners collected data on the demographics of the horses (n = 274) and feeding practices. The median age was 8 years, the majority being warmblood and geldings with a mean bodyweight of 542.4 ± 101.9 kg. Most horses (85 %) had access to a limited area of pasture (<200m2 per horse), with a median grazing time of 10 hours. Grass hay was the predominant conserved forage offered (77 %) within diets. Concentrate feeds were provided to most horses (93.8 %) as well as the dietary supplements (80 %). The majority of the horses were offered high levels of metabolizable energy (ME) (90 %), starch (mean 2.4 ± 0.8 g/kg bw) and sugar intake (mean 1.4 ± 1.2 g/kg bw) compared to NRC recommendations. The estimated potential nitrogen excretion per horse per day was 228 ± 134 g, or 8.47 kg of nitrogen per ton of manure. Consequently, the estimated daily fecal excretion rates of microminerals for each horse were as follows: Copper (Cu) at 141.0 ± 151.3 mg, Zinc (Zn) at 593.1 ± 504.4 mg, Manganese (Mn) at 957 ± 541.2 mg, and Cobalt (Co) at 2.3 ± 3.5 mg. The analysis indicated that many equine diets in the Netherlands offered excess ME, CP and the minerals Cu, Zn, Mn and Co. To mitigate these concerns, it is crucial to promote sustainable feeding practices and better educate horse owners.

Influence of various sources of amino acids on composition of intestinal microflora of meat chickens and roosters of parent herd of cross “Smena 9”

Relevance. The intensin’s microbiota plays a crucial role in feed digestion and nutrient digestion in farm poultry, influencing zootechnical performance.The aim of the study was to compare the effect of the addition of lysine and methionine in various forms to the diet on the composition of the intestinal microflora of chickens and roosters of the «Smena 9» cross, as well as to establish a connection between the composition of microflora in different diets with the zootechnical indicators of birds.Methods. Physiological reseach were carried out on meat chickens of the Plimutrock breed and roosters of the Cornish breed of the parent herd of the domestic cross “Smena 9” selection of the “Smena” SSC. 4 groups were formed (control 1A and experimental 2A-4A) such as of 9 laying heads and 4 groups of 9 rooster heads (control 1B and experimental 2B-4B). Analysis of samples of the contents of blind processes of the intestine of birds was carried out by PCR.Results. As shown by the quantitative PCR method, the studied feeding factors: various sources of lysine and methionine and a 5% reduced level of metabolic energy of feed had a different effect on the composition of the microflora of chickens and roosters of the parent stock of the new cross «Smena 9». For example, with a decrease in the level of metabolic energy in the diets of chickens, there was a decrease from 1.2 to 5.0 times in such representatives of the normoflora as Bacteroidetes and Eubacteriaceae, compared with similar groups with a basic amount of metabolic energy (p &lt; 0.05). When lysine was introduced into the diet in the form of monochlorohydrate and DL-methionine, a decrease in the weight of ovaries with an oviduct by 6.9 g was noted against the background of a decrease in the level of metabolic energy compared with the corresponding group with a base content of metabolic energy (p ≤ 0.05), whereas when using lysine in the form of sulfate and methionine in the form of a hydroxyanalog of methionine, a similar effect was reduced not noted (p &gt; 0.05). At the same time, shifts in the composition of microflora against the background of changes in diets did not have any connection with the studied zootechnical parameters in chickens and roosters.

Triticale: A General Overview of Its Use in Poultry Production

Triticale, a hybrid of wheat and rye, is one of the most promising grain crops. In terms of productivity, the level of metabolizable energy, and the composition of essential amino acids, triticale surpasses rye and is not inferior to wheat. It is resistant to the most dangerous diseases and pests. In terms of nutritional value, triticale can compete with wheat, corn, sorghum, and barley. The presence, however, of antinutrients in triticale such as non-starch polysaccharides, alkylresorcinols, and trypsin inhibitors significantly reduces the biological value of this crop. In the global practice of compound feed production, there are many methods and technologies for processing grain raw materials to increase their nutritional value. Enzymatic treatment and extrusion technologies are worthy of special attention. The high content of triticale in the compound feed of poultry breeder flocks should be used effectively, taking into account the characteristics of triticale varieties and climatic conditions. An optimal triticale level in feed (15% for layer and broiler chicks) may improve body weight gain and reduce feed costs when raising replacement young stock. Layer breeder flocks fed a 20% triticale-based diet may have increased egg production, high viability, and flock uniformity. Producing triticale–soy and triticale–sunflower extrudates and supplementing the diet of poultry flocks with essential amino acids represent promising avenues for maximizing the benefits of triticale. Innovative methods of achieving this goal should be further developed and put into practice, particularly given the expansion of triticale’s cultivation areas.

Effect of metabolizable energy levels and conditioning temperatures on broiler performance, processing yield, footpad lesions, and nutrient digestibility from 1 to 42 d of age

Effect of metabolizable energy levels and conditioning temperatures on broiler performance, processing yield, footpad lesions, and nutrient digestibility from 1 to 42 d of age

The effect of reducing dietary energy on performance, intestinal morphology and intestinal peptide and amino acid transporters in broiler chicks

AbstractBackgroundPrevious research has investigated the impact of different factors such as gender and age of birds, protein and amino acid levels, protein origin and the physical form of the diet, on the mRNA expression of intestinal peptides and amino acid transporters. Nevertheless, there have been no attempts to examine the impact of dietary energy density on the mRNA abundance of intestinal amino acid and peptide transporters in humans or animals. This is the first reported case in both humans and animals.ObjectivesThis experiment aimed to evaluate the influence of two levels of metabolizable energy ([ME]; 2950 and 2850 kcal ME/kg diet) on performance and jejunal morphology and mRNA expression of amino acid (B0AT, b0,+AT, CAT1 and y+LAT1) and peptide (PepT1) transporters in broiler chickens during the starter period (0–10 days of age).MethodsTwo hundred and seventy day‐old male Ross 308 broiler chickens were randomly assigned to two dietary treatments with nine replicates and fifteen birds in each replicate. At 10 days of age, the outcome variables were measured, which included the assessment of the mRNA abundance of PepT1, b0,+AT, B0AT, y+LAT1 and CAT1 in the jejunal section using real‐time PCR.ResultsThe findings of this study revealed no significant impact of the dietary treatments on feed intake, body weight gain, feed conversion ratio and the jejunal mRNA abundance of PepT1, CAT1 and y+LAT1 (p &gt; 0.05). However, a reduction in dietary ME level from 2950 to 2850 kcal ME/kg diet resulted in a decrease in the mRNA level of B0AT and b0,+AT (p ≤ 0.05). The reduction in dietary energy level did not lead to any significant changes in villus width, villus height, crypt depth, villus surface area and villus height to crypt depth ratio (p &gt; 0.05).ConclusionThe results demonstrated that decreasing dietary energy density may alter the expression of amino acid transporters in the intestine while having no impact on the growth performance and morphometric structure of the intestine.

Multi-omics revealed the effects of dietary energy levels on the rumen microbiota and metabolites in yaks under house-feeding conditions.

Yak (Bos grunniens) is a unique large ruminant species in the Qinghai-Tibetan Plateau (QTP). Changing the energy levels of their rations can significantly improve their growth performance. Therefore, studying the effects of dietary energy levels on the rumen microflora and metabolites of yak is crucial for enhancing the development of the yak industry. Currently, there is a lack of understanding regarding the impact of feeding energy diets on rumen fermentation parameters, microbial functions, and metabolites. This study was designed to determine the appropriate energy level for feeding yak. Three test diets with metabolizable energy levels of 7.57 MJ/kg, 9.44 MJ/kg, and 11.9 MJ/kg were used and the concentration of volatile fatty acids (VFA) in rumen fluid was measured. The microbial communities, functions, and metabolites in yaks were studied by 16S rRNA sequencing, metagenome, and LC-MS non-targeted metabolomics to investigate the relationships among rumen fermentation parameters, microbial diversity, and metabolites. Ration energy levels significantly affect total VFA, acetate, propionate, butyrate, iso-valerate, valerate, and acetate/propionate (p < 0.05). At the phylum level, the dominant phyla in all three treatment groups were Bacteroidota, Firmicutes, and Actinobacteriota. At the genus level, the abundance of the unclassified_o__Bacteroidales, norank_f_Muribaculaceae, Lachnospiraceae_NK4A136_group, and Family _XIII_AD3011_group showed significant differences (p < 0.05) and were significantly correlated with differential metabolites screened for phosphatidylcholine [PC(16:0/0:0), PC(18:3/0:0)], uridine 3'-monophosphate, and adenosine monophosphate, etc. CAZymes family analysis showed that GHs and CEs differed significantly among the three groups. In addition, differential metabolites were mainly enriched in the pathways of lipid metabolism, nucleotide metabolism, and biosynthesis of other secondary metabolites, and the concentrations of differential metabolites were correlated with microbial abundance. In summary, this study analyzed the effects of ration energy levels on rumen microorganisms and metabolites of yaks and their relationships. The results provided a scientific basis for the selection of dietary energy for yaks in the house feeding period in the future.

The effects of β-mannanase supplementation on growth performance, digestive enzyme activity, cecal microbial communities, and short-chain fatty acid production in broiler chickens fed diets with different metabolizable energy levels.

This study assessed the effects of β-mannanase (BM) supplementation on growth performance, digestive enzyme activity, cecal microbial communities, and short-chain fatty acid (SCFA) production in broiler chickens fed diets with different metabolizable energy (ME) levels. A total of 1,296 male 1-d-old Cobb 500 broilers were randomly distributed in a 3 × 2 factorial arrangement (3 ME levels × 0 or 200g/ton BM), with 6 replicates per treatment combination. The 3 ME levels were 3,000 (ME1), 2,930 (ME2), and 2,860 (ME3) kcal/kg, respectively, during the 0 to 3 wk-old stages and 3,150 (ME1), 3,080 (ME2), and 3,010 (ME3) kcal/kg, respectively, during the 3 to 6 wk-old stages. Reducing ME levels increased broiler feed intake (P = 0.036) and decreased average daily gain (ADG, P = 0.002) during the entire period. While BM supplementation increased ADG (P = 0.002) and improved the feed conversion ratio (P = 0.001) during the 0 to 3 wk-old stages, with no effect during the 3 to 6 wk-old stages. Overall, reducing ME levels increased pancreatic lipase (P = 0.045) and amylase (P = 0.013) activity and duodenal amylase activity (P = 0.047). Notably, BM supplementation significantly increased pancreatic lipase activity (P = 0.015) and increased lipase (P = 0.029) and amylase (P = 0.025) activities in the jejunal chyme. Although diet or enzyme supplementation did not affect microbial diversity, significant differences in microbial communities were observed. At the genus level, decreasing ME levels significantly affected the average abundances of Tyzzerella (P = 0.028), Candidatus_Bacilloplasma (P = 0.001), Vibrio (P = 0.005), and Anaerotruncus (P = 0.026) among groups, whereas BM supplementation reduced the average abundances of Escherichia-Shigella (P = 0.048) and increased the average abundances of Barnesiella (P = 0.047), Ruminococcus (P = 0.020), Alistipes (P = 0.050), and Lachnospiraceae_unclassified (P = 0.009). SCFA concentrations strongly depended on bacterial community composition, and BM supplementation increased acetic acid (P = 0.004), propionic acid (P = 0.016), and total SCFA concentrations. In conclusion, BM supplementation improved the performance of younger broilers, and both enzyme supplementation and reduced ME levels positively affected digestive enzyme activity and intestinal microflora.

Effects of dietary xylanase supplementation on growth performance, intestinal health, and immune response of nursery pigs fed diets with reduced metabolizable energy.

This study aimed to investigate the effects of xylanase on growth performance and intestinal health of nursery pigs fed diets with reduced metabolizable energy (ME). One hundred ninety-two pigs at 8.7 kg ± 0.7 body weight (BW) after 7 d of weaning were allotted in a randomized complete block design with initial BW and sex as blocks. Eight dietary treatments consisted of 5 ME levels (3,400, 3,375, 3,350, 3,325, and 3,300 kcal ME/kg) below the NRC (2012) requirement and 4 levels of xylanase (0, 1,200, 2,400, and 3,600 XU/kg) to a diet with 3,300 kcal ME/kg. All pigs received their respective treatments for 35 d in 2 phases, pre-starter (14 d) and starter (21 d). On day 35, eight pigs in 3,400 kcal/kg (CON), 3,300 kcal/kg (LE), and 3,300 kcal/kg + 3,600 XU xylanase/kg (LEX) were euthanized to collect jejunal tissues and digesta for the evaluation of mucosa-associated microbiota, intestinal immune response, oxidative stress status, intestinal morphology, crypt cell proliferation, and digesta viscosity as well as ileal digesta to measure apparent ileal digestibility. Data were analyzed using the MIXED procedure on SAS 9.4. The LE increased (P < 0.05) jejunal digesta viscosity, tended to have decreased (P = 0.053) relative abundance of Prevotella, and tended to increase (P = 0.055) Lactobacillus. The LE also increased (P < 0.05) the concentration of protein carbonyl whereas malondialdehyde, villus height (VH), villus height to crypt depth ratio (VH:CD), apparent ileal digestibility (AID) of nutrients, and finally average daily feed intake were decreased (P < 0.05). The LE did not affect average daily gain (ADG). The LEX decreased (P < 0.05) digesta viscosity, increased (P < 0.05) the relative abundance of Prevotella, decreased (P < 0.05) Helicobacter, decreased (P < 0.05) the concentration of protein carbonyl, tended to increase (P = 0.065) VH, and decreased (P < 0.05) VH:CD and crypt cell proliferation. Moreover, LEX increased (P < 0.05) the AID of dry matter and gross energy and tended to increase (P = 0.099; P = 0.076) AID of crude protein, and ether extract. The LEX did not affect ADG but did tend to decrease (P = 0.070) fecal score during the starter phase. Overall, reducing ME negatively affected intestinal health parameters and nutrient digestibility without affecting growth. Supplementation of xylanase mitigated some of the negative effects observed by ME reduction on intestinal health and digestibility of nutrients without affecting growth.

Effects of various levels of metabolizable energy in pre-starter diets of broiler chickens on growth performance

The pre-starter diet is critical for providing adequate nutrition to newly hatched chicks, whose digestive systems are not yet fully developed to handle solid feeds. Different levels of dietary energy can impact the growth and development of broilers. Hence, providing the right energy to meet their requirements is necessary. A study was conducted to examine the effect of different levels of metabolizable energy (ME) (3025, 2904, and 2783 kcal/kg) in the pre-starter diet (1 to 10 days) of broiler chickens on their growth performance traits. The experiment involved 450 broilers of the Ross 308 breed, divided into three treatments and six replications. The results of the study showed that reducing dietary energy levels increased the feed intake (FI) and body weight (BW) of broiler chickens, although it did not affect their feed conversion factor (FCR). Based on the results of the current study, reducing the recommended energy levels by up to 5% had no negative impact on growth performance. This can be useful in reducing the feed expense in broiler production.

Níveis de energia metabolizável e proteína bruta sobre a taxa de postura e a qualidade de ovos de codornas em fase de postura

ABSTRACT: This study evaluated the zootechnical performance of 192 laying quails, receiving diets with different levels of crude protein (18 and 19%) and metabolizable energy (2,500, 2,600, 2,700 and 2,800 kcal/kg), in a 2 x 4 factorial arrangement. The experiment consists of four experimental periods of 28 days each, where feed intake (g/bird), feed conversion (by dozens of eggs and egg mass), laying rate, weight and mass of eggs and indices of egg quality (yolk, shell and albumen content, shell thickness, Haugh unit). Results indicated that reducing feed energy levels to 2,500 and 2,600 kcal/kg increased feed intake (P &lt; 0.05). However, reducing protein levels to 18% did not change (P &gt; 0.05) feed intake. No differences (P &gt; 0.05) were observed in laying rate, feed conversion per dozen eggs and egg mass, and egg quality indices, in relation to energy or protein levels. There were no interactions between dietary energy and protein levels. In conclusion, the reduction of metabolizable energy levels to 2,500 kcal/kg and crude protein to 18% in diets for laying quails, from 52 to 68 weeks of age, is a viable alternative to reduce production costs, without harming performance and egg quality.

Impact of elevated levels of metabolisable energy and protein on immunity, health and growth performances in male Murrah buffalo calves

Impact of elevated levels of metabolisable energy and protein on immunity, health and growth performances in male Murrah buffalo calves

Impact of Emulsifier Supplementation with Varying Levels of Metabolizable Energy on Production Performance, Egg Quality and Blood Parameters of Commercial Layers

Impact of Emulsifier Supplementation with Varying Levels of Metabolizable Energy on Production Performance, Egg Quality and Blood Parameters of Commercial Layers

The effect of lime leaf extract (Citrus aurantifolia) through drinking water on the chemical and physical quality of broiler meat

This study aims to investigate the impact of supplementing lime leaf extract (EDJ) in broiler chickens' drinking water on both the chemical and physical qualities of their meat. A total of 128 New Lohmann MB 202 strain broiler roosters were subjected to the same basal feed regimen but received distinct drinking water treatments over a 35-day rearing period. The drinking water treatments included plain water without additives (negative control; T0), water supplemented with 50 ppm Tetracycline antibiotics (positive control; T1), water enriched with 15 ml/liter EDJ (T2), and water infused with 30 ml/liter EDJ (T3). The basal diet consisted of corn and soybean flour, with a crude protein content of 22.01% and a metabolic energy level of 3113.12 kcal/kg. Feed and drinking water are provided ad libitum during the rearing period. The parameters observed in this study were the chemical and physical quality of the meat, which included variables: moisture content, ash content, protein content, fat content, pH value, water holding capacity, cooking loss, and tenderness. The data obtained were then analyzed for variance (ANOVA) using a one-way Complete Randomized Design based on a P value of less than 5%. The findings of the study indicated that the supplementation of EDJ through drinking water did not produce significant alterations in water content, protein content, fat content, cooking loss, or tenderness of the broiler meat. However, a notable outcome was observed: the addition of 30 ml/liter of EDJ to the drinking water led to a substantial increase in water holding capacity (P&lt;0.05) while simultaneously reducing the meat's pH value (P&lt;0.05). These results suggest that EDJ supplementation has the potential to enhance the physical quality of broiler meat, primarily by increasing water retention and decreasing pH values, which can contribute to improve meat texture and juiciness.

Effects of Metabolizable Energy Intake and Body-Weight Restriction on Layer Pullets: 1-Growth, Uniformity, and Efficiency

This study aimed to determine the effects of dietary energy and body-weight (BW) restriction on layer pullets’ growth, uniformity, and feed efficiency. Two experiments were conducted using a precision feeding (PF) system (Experiment 1) and a conventional feeding (CON) system (Experiment 2). Experiment 1 consisted of a 2 × 4 factorial arrangement (eight treatments) with two feed allocation (FA) levels: meal every visit (MEV) or restricted to the lower boundary of Lohmann Brown-Lite pullets; and three dietary metabolizable energy (ME) levels: Low, Standard (Std), and High (2600, 2800, and 3000 kcal/kg, respectively); the fourth treatment enabled birds to choose from the three diets (Choice). Experiment 2 consisted of a 2 × 3 factorial arrangement (six treatments): two FA levels (ad libitum or restricted) and three dietary ME levels (Low, Std, and High). In each experiment, BW, coefficient of variation (CV), average daily feed intake (ADFI), average daily metabolizable energy intake (MEI), and feed conversion ratio (FCR) were recorded. Diet ADFI preferences and feeding motivation were determined only in the PF experiment. ANOVA was conducted on each experiment with the two main effects as fixed factors (FA and dietary ME), and age or period as the sources of variation. Differences were reported at p ≤ 0.05. MEV (PF experiment) and ad libitum-fed (CON experiment) pullets had greater BW compared to restricted-fed pullets (p &lt; 0.05). The lowest CV was observed in the restricted-fed pullets from the PF experiment (p &lt; 0.05). ADFI was greater in pullets fed the Low ME diet in the PF experiment compared to all the other groups, and the lower the dietary ME, the greater the ADFI in the CON experiment (p &lt; 0.05). Choice-feeding pullets preferred feed with greater ME content in the PF experiment (p &lt; 0.05). The lower the dietary ME, the greater the FCR in the CON experiment (p &lt; 0.05). Restricted-fed pullets had greater daily visits, and lower daily meals, meal size, and successful visits to the PF system (p &lt; 0.05). In conclusion, the results of this trial indicated that lower dietary ME increased FCR and ADFI, whereas feed restriction decreased BW and increased feeding motivation. Future steps after this trial will include examining the effects of dietary energy and feed restriction on carcass composition and sexual maturation.

273 Effects of Xylanase Supplementation in Diets with Reduced Metabolizable Energy and Supplemental Fat on Intestinal Health, Mucosa Associated Microbiota and Growth Performance of Nursery Pigs

Abstract This study aimed to investigate the effects of reducing metabolizable energy (ME) below the requirement by reducing supplemental fat on intestinal health and growth performance of nursery pigs. One hundred and ninety-two newly weaned pigs at 7.3 ± 0.6 kg BW were allotted in a RCBD with sex and initial BW as blocks. Pigs were assigned to one of 8 dietary treatments with varying ME levels (3,400, 3,375, 3,350, 3,325, and 3,300 kcal/kg ME) by reducing supplemental fat and increasing xylanase (X0: 0, X40: 1,200, X80: 2,400 and X120: 3,600 XU/kg of feed) in ME deficient diets by 100 kcals/kg. Pigs were fed diets for 35 d in 2 phases (14 d and 21 d, respectively) and growth performance was measured at the end of each phase. Phase 2 diet had titanium dioxide (0.4%) as indigestible external marker to measure ileal digestibility of nutrients. At d 35, a pig representing the median BW within each pen from 3 dietary treatments (ME at 3,400 and 3,300 kcal/kg ME with or without xylanase) were euthanized for sampling jejunal mucosa, jejunal tissue, and ileal digesta to analyze intestinal health parameters, mucosa associated microbiota, and apparent ileal digestibility (AID) of nutrients. Data were analyzed using Mixed procedure of SAS 9.4. Overall, reducing ME level had no effect on growth performance of nursery pigs. However, reducing ME by 100 kcal/kg ME below the requirement increased (P &amp;lt; 0.05) digesta viscosity (1.7 to 2.2 cP) and protein carbonyl (0.18 to 0.40 nmol/mg), tended to change the relative abundance of Prevotellaceae (P = 0.062, 49 to 23%) and Lactobacillaceae (P = 0.086, 7 to 19%), reduced (P &amp;lt; 0.05) villus height (467 to 433 µm) and villus height to crypt depth ratio (1.80 to 1.64) in the jejunum, and reduced (P &amp;lt; 0.05) AID of DM (59.5 to 47.3%), gross energy (59.1 to 43.0%), crude protein (63.4 to 44.6%), and ether extract (67.7 to 55.2%). Xylanase supplementation decreased (P &amp;lt; 0.05) digesta viscosity (2.2 to 1.82 cP) and protein carbonyl (0.40 to 0.17 nmol/mg), increased the relative abundance of Prevotellaceae (20.22 to 61.56%), increased villus height (433 to 462 µm) and villus height to crypt depth ratio (1.64 to 1.99) in the jejunum, and increased (P &amp;lt; 0.05) AID of DM (47.3 to 58.7%), and gross energy (42.9 to 56.0%). In conclusion, reducing ME (100 kcal/kg below the requirement) by reducing supplemental fat (by 2% unit) impaired intestinal health, reducing ability of the pigs to digest feeds whereas xylanase supplementation appeared to mediate some of the negative effects seen by energy reduction by improving intestinal morphology, reducing oxidative damage products, and diversity of the mucosa-associated microbiota.

222 Effects of Nutritional Strategies of Growth Rate Manipulation During the Gilt Development Phases on Growth and Reproductive Performance

Abstract Our objective was to evaluate the effects of nutritional interventions for growth rate manipulation during the gilt development phases on growth and reproductive performance. A total of 810 Camborough L42 gilts from three gilt groups were received between 9 to 11 weeks of age. Gilts were individually weighed, and pens of gilts were allotted to one of two dietary treatments balanced by lot (birth week) and pen weight for a total of 24 pens/treatment. Treatments consisted of two levels of dietary nutrients:1) diets based on corn, soybean meal, and wheat middlings formulated to meet or exceed the PIC standardized ileal digestible (SID) lysine (Lys) recommendations with a total dietary fiber content (TDF) of 10, 10, and 11% (Adeq); and2) slower growing diets based on corn, soybean meal, wheat middlings, and corn germ where SID Lys was reduced by 6, 11, and 11%, dietary metabolizable energy level was reduced by 2.7, 4.6, and 4.7%, and TDF content was increased to 15, 18, and 20% (Low). Diets were fed in three phases as 27.2 to 54.5 kg, 54.5 to 81.8 kg, and 81.8 to 113.6 kg of body weight (BW). At the end of phase 3, gilts were individually weighed and the number of selected gilts per pen was recorded. After selection, gilts were heat checked with the date of heat-no-service (HNS) recorded and then sent to sow farms for breeding in the next recorded heat. Data were analyzed using generalized linear mixed models considering treatment as fixed effect, lot as random effect, and covariates were included if they were statistically significant and improved model fit. Gilts fed the Low diets had less overall average daily gain compared with gilts fed Adeq diets (P &amp;lt; 0.05; Table 1). This response was mainly driven by a marginal significant reduction (P &amp;lt; 0.10) in average daily feed intake for the gilts fed Low diets compared with Adeq, with no evidence for differences (P &amp;gt; 0.10) in overall feed efficiency. As a result of the reduction in growth rate, gilts fed the Low diets were 4.8 kg lighter (P &amp;lt; 0.05) at selection compared with gilts fed Adeq diets. There was no evidence for treatment differences in selection rate, breeding rate, age at first HNS nor age at first breeding (P &amp;gt; 0.10). In summary, results from this study demonstrated that nutritional strategies can be applied to reduce developing gilts growth rate without negatively affecting puberty, selection rate, or age at first breeding.

Multi-enzymatic complex on growth performance, blood parameters, and economic viability in piglets

The aim of the present study was to evaluate the dietary effect of an enzymatic complex on the growth performance variables, blood parameters, and economic viability of piglets. To achieve this, we used 80 piglets (40 castrated males and 40 females) in a 2 × 2 factorial design following a randomized block experimental distribution, with two levels of metabolizable energy (adequate: 3206.09 and low: 3005.45 kcal kg-1) and two enzyme levels (0 and 50 g ton-1). The results showed no significant difference between treatments in the growth performance variables or blood parameters of piglets. The economic viability, economic efficiency index, and cost index were improved when we used a diet with a low energy supplemented with the enzyme complex as compared to other experimental diets. Thus, we concluded that enzyme complex supplementation can maintain growth performance and blood parameters in piglets even when they are fed low energy diets. Moreover, this could reduce production costs.

Effect of different energy, protein levels and their interaction on productive performance, egg quality, digestibility coefficient of laying Japanese quails

For the evaluation of the effects of various quantities of crude protein (CP) and metabolizable energy (ME) (kcal/kg diet) in Japanese quail lay chicken meals on performance, digestion coefficients, and nutritional value. An experiment was undertaken in the summer season; 216 eight-wk-old Japanese quail laying hens were allocated at random to 1 of 9 groups in a factorial design (3×3) experiment involving 3 levels of CP (18, 20, and 22%) plus 3 levels of ME (2,800, 2,900, or 3,000 kcal/kg ME diet). The testing period lasted from 8 to 20 wk. The findings demonstrated that the relationship between protein and energy levels significantly impacted all productive outcomes except the feed conversion ratio (P < 0.01). Throughout the overall period 8 to 20 wk of age, the greatest measurements of egg weight (11.9 g) and egg mass (8.33 g) occurred in hens fed 20% CP with 2,900 kcal/kg diet, yet the lowest values of egg weight (11.2 g) and egg mass (6.72 g) were noticed in hens fed 22% CP with 2,900 kcal/kg diet. The data showed that the combination of dietary energy and protein levels had a substantial (P < 0.05 and P < 0.01) effect on all egg quality trials evaluated. The results indicated that the interaction between dietary energy and protein concentrations substantially impacted DM and EE digestion ratios (P < 0.01). Finally, when feeding layer Japanese quail between the ages of 8 and 20 wk during the summer, a dietary energy content of 2,900 kcal ME/kg with 20% CP is recommended.