Metabolizable Energy Intake Research Articles

Effect of Processed Coffee Husk on Feed Intake, Nutrient Digestibility, Body Weight Changes and Economic Feasibility of Bonga Sheep Fed on Natural Pasture Hay as a Basal Diet

ABSTRACTBackgroundEthiopia is one of the world's coffee producers, generating about 192,000 metric tonnes of coffee husks annually as by‐products. The material can be used for ruminant diets to improve the nutrient utilisation of animals. However, coffee husk has toxic compounds, which can be minimised through different processing methods. Though the above techniques can minimise the toxicity level of coffee husk and increase the bioavailability of nutrients, there is scanty information on the comparative efficacy of these techniques, especially in ruminant nutrition.ObjectiveThe study was conducted to examine the effect of processed coffee husk on feed intake, nutrient digestibility, body weight changes and profitability of Bonga rams based on natural pasture hay.MethodsIn the experiment, 24 rams were used, and the rams were grouped into six blocks based on initial body weight (mean BW 21.5 ± 1.01 kg). The rams were quarantined for 21 days, and each ram was randomly assigned to one of the experimental feed treatments in a randomised complete block design (RCBD). The experimental treatment feeds include 400 g conventional concentrate mix (CM) containing Noug seed cake and wheat bran (T1); 200 g boiled coffee husk + 200 g CM (T2); 200 g roasted coffee husk + 200 g CM (T3) and 200 g raw coffee husk + 200 g CM (T4). The CM was made in the ratio of 1:1. The data collected from the 90‐day experimental period were: dry matter and nutrient intakes, initial body weight, final body weight and body weight changes. After the growth experiment, a 7‐day digestibility trial was followed by collecting faeces using a harness bag. The data were managed using Microsoft (MS) Excel 2010 and analysed using R software (v. 4.3.2). The chemical compositions of the CM had maximum crude protein (22%), followed by boiled coffee husk (14.74%), which was higher than natural pasture hay (6.91%) and raw coffee husk (12.4%).ResultsThe total dry matter intake (p < 0.05), metabolisable energy, and total nutrient intakes of rams were significantly (p < 0.001) maximised when rams fed on boiled coffee husk (T2) than raw (T4) and roasted (T4) coffee husk, except for NDF and organic matter intakes. The apparent digestibility of nutrients and feed conversion efficiency were maximised for rams assigned to T2. There was maximum daily body weight gain (p < 0.001) when rams were supplemented with boiled coffee husk (T2). Also, body weight changes of rams were significantly (p < 0.001) higher for rams supplementation with boiled coffee husk.ConclusionTherefore, the boiled coffee husk as an alternative feed resource can be replaced by about half of the commercial CM without adverse effects of anti‐nutritional factors and enhance the income of smallholder farmers in the coffee crop‐livestock production system.

A systematic review and meta-analysis of cow-level factors affecting milk urea nitrogen and urinary nitrogen output under pasture-based diets

With dairy cattle farming under pressure to lower its environmental footprint it is important to find effective on-farm proxies for evaluation and monitoring of management practices aimed at reducing the risk of nitrogen (N) losses and optimizing N use efficiency of dairy farm systems. Urinary N (UN) is regarded as the most potent source of N emissions. In contrast to confinement systems, there have been few studies from pasture-based systems associating on-farm animal and nutritional factors with UN output. Thus, the aims of this meta-analysis were to collate a database from pasture-based research to: (a) investigate the associations of management, dietary, and animal variables with MUN concentration, and daily UN output; (b) describe the MUN-UN association; and (c) assess whether animal, management, and dietary factors influence the relationship. We developed a data set consisting of 95 observations representing 919 lactating dairy cattle fed pasture-based diets, which was compiled from 32 unique research publications that reported both MUN and UN output. Multi-level, mixed meta-analysis regression techniques were used to analyze the data. Initially, all variables were assessed as the sole fixed effect in a 2-level random effects model, accounting for within publication heterogeneity. Meta-regression techniques were then used to assess the relationship of all variables with MUN and UN output, respectively, accounting for 3 sources of variability: the sampling error of the individual observation, within publication heterogeneity, and among publication heterogeneity. At the univariable level, despite more than 10 dietary, animal, or management variables being significantly associated with MUN, none explained a large amount of the MUN variation. The variables that explained the greatest amount of variation were dietary crude protein (CP) content and the nitrogen: metabolizable energy content ratio, which explained about 33% and 31% of the variation in MUN concentrations, respectively. Combining factors in multiple regressions improved the model fit, such that the variation within publications explained by dietary CP and N intake increased to 40.0% in the final multiple meta-regression model. For UN output, individual variables explained a greater proportion of variance reported among observations, compared with MUN, whereby diet CP content (pseudo R2 = 66.1%), N to metabolizable energy intake ratio (pseudo R2 = 64.0%), N intake (pseudo R2 = 58.3%), and MUN (pseudo R2 = 43.5%) explained the greatest amount of the total variation. Milk urea nitrogen, N intake and dry matter intake were associated with UN output in the final multiple meta-regression model. Substantial heterogeneity existed in both MUN and UN among publications, with among publication heterogeneity accounting for 73.4% of all the variation noted in MUN, and 88.6% of all the variation in UN output. As such, the meta-analyses could not predict MUN and UN to any great extent. It is recommended that a consistent approach to measuring and reporting MUN concentrations and UN output is carried out for all future research in pasture-based systems.

Estimating net energy requirements of male Djallonke sheep

Context Energy requirements in sheep can vary significantly due to various factors, including age, breed, sex and environmental conditions. Genetic selection and crossbreeding further contribute to this variability. Although guidelines from the US and UK national research councils are commonly used for formulating sheep diets, they may not adequately account for the unique characteristics of sheep in Africa. Aims The study aimed to estimate the net maintenance energy requirement of male Djallonke sheep. This estimation will provide a basis for comparing the energy requirements of Djallonke sheep with national recommendations and recent estimates for other sheep breeds. Methods Sixteen entire male Djallonke sheep were selected and grouped by weight. They were then randomly allocated to four treatment groups in a 4 × 4 Latin square design. The sheep were fed to achieve intake levels ranging from 1 to 1.75 multiples of their maintenance energy requirement. Gas exchange data were collected using the GreenFeed system over a 3-day period at the conclusion of each treatment period. Heat production was calculated using the established Brouwer’s equation. A linear regression equation was developed to relate heat production to metabolisable energy intake scaled by metabolic bodyweight to calculate the net energy for maintenance. Key results The estimated net energy for maintenance for male Djallonke sheep was determined to be 0.354 MJ/kg BW0.75. This estimation indicated that the energy requirements of male Djallonke sheep exceeded the recommendations provided by the US National Research Council and the UK Agricultural and Food Research Council. However, it closely aligned with an updated estimate of 0.358 MJ/kg BW0.75. Conclusions Based on the study’s findings, male Djallonke sheep have higher energy requirements for maintenance than what is commonly recommended by existing guidelines. Therefore, it is advisable to update ration formulation software for male Djallonke sheep to better reflect their actual energy requirements for maintenance. Implications These results have practical implications for the formulation of diets and feeding management practices for male Djallonke sheep. Adhering to updated energy requirement estimates can help improve the efficiency and productivity of sheep production in the context of Djallonke sheep farming.

Methane emission, nitrogen excretion, and energy partitioning in Hanwoo steers fed a typical TMR diet supplemented with Pharbitis nil seeds.

Two in vivo experiments were conducted to evaluate the potential of Pharbitis nil seeds (PA) as an anti-methanogenic additive to ruminant feed. In experiment 1, six Hanwoo steers (459.0 ± 25.8 kg) were fed either a total mixed ration (TMR; 32-d period) or TMR supplemented with PA at 5% dry matter (DM) intake (TMR-PA; 45-d period) for two consecutive periods. Fecal and urine outputs were measured in an apparent digestibility trial in both periods. Methane (CH4) yield and heat energy (HE) were measured using respiratory chambers equipped with gas analyzers. In experiment 2, five rumen cannulated Holstein steers (744 ± 35 kg) were fed the same TMR or TMR-PA diets for 40 days; rumen samples were collected at 0, 1.5, and 3 h after feeding on the last day of the feeding period. In experiment 1, although there were no differences (p > 0.05) in nutrients or gross energy intake (GEI) between the groups, an increase (p < 0.05) in the apparent digestibility of DM (9.1%) and neutral detergent fiber (22.9%) was observed in the TMR-PA fed Hanwoo steers. Pronounced decreases (p < 0.05) in CH4 (g/Kg DM; 17.1%) and urinary N excretion (% N intake; 7.6%) were observed in the TMR-PA group, leading to a 14.7% increase in metabolizable energy intake (% GEI). However, only a numerical increase (p > 0.05) in retained energy was observed due to the increase in HE loss. In experiment 2, a drastic decrease (p < 0.05) in rumen ammonia concentration (56.3%) associated with an increased (p = 0.091) rumen short-chain fatty acid concentration 1.5 h after feeding were observed in TMR-PA fed Holstein steers. A 26.6% increase (p < 0.05) in the propionate proportion during the treatment period clearly reflected a shift in the ruminal H2 sink after 3 h of feeding. A 40% reduction (p = 0.067) in the relative abundance of rumen protozoa Entodinium caudatum was also observed. It was concluded that PA could be a natural feed additive for CH4 and N emission abatement.

446 A stochastic, dynamic agent-based model of swine nutrient requirements for the growing finishing production phase

Abstract Agent-based modeling (ABM) is a powerful tool that offers the flexibility to represent the stochasticity exhibited by swine systems due to individual animal nutritional requirements. ABM can also accurately mimic the biological dynamic growth performance of pigs. Addressing and simulating the biological growth dynamics enables precision nutrition and sustainable production management. To realistically replicate the nutrient requirement and growth performance of growing-finishing pigs, we developed an ABM based on the principles and equations from the eleventh Swine Nutrient Requirement Council Model. Each individual pig (agent) in the model had a starting weight of 20 kg and a fixed finishing weight of 140 kg, with a variable number of days on feed. Our model considers three sexes: gilt, barrow, and intact male. Pigs move through the farm, feed, and interact with the environment. Our model dynamically simulates the complex interactions between feed intake, metabolism, and growth processes of growing pigs, thereby being a virtual visualizable growing-finishing swine farm (Figure 1). The basic parameters of the biological growth of pigs, including the body weight, feed intake, metabolizable energy (ME) intake, maintenance ME requirements, protein deposition (Pd), lipid deposition (Ld), and probe backfat thickness (Figure 2), were modeled based on NRC equations. In addition to the above parameters, the daily amino acid, calcium (Ca), and phosphorus (P) requirements for individual pigs were calculated daily. To demonstrate ABM responsiveness to feeding strategies, ractopamine supplementation is included to evaluate the impact on protein deposition. The ABM offers more personalized nutrition management by considering unique pig growth potential and nutritional needs based on characteristics such as age and sex, which can lead to improved growth performance and feed efficiency. Besides, the ABM enables the modeling of population-level dynamics and the evaluation of different feeding scenarios to optimize growth outcomes by allocating optimized feed based on individual nutritional needs. Our ABM will be used to test different feeding management strategies and scenarios, providing valuable insights into the impact of various factors on pig nutrition and growth outcomes while minimizing both time and financial expenditures. Our ABM aims to provide a robust framework for simulating and optimizing feeding strategies and enhancing overall pig production efficiency by leveraging the comprehensive and scientifically validated guidelines provided in the NRC. To verify the accuracy and reliability of the proposed ABM, the results generated by the model were rigorously evaluated and compared with the NRC model results. The results demonstrated a highly satisfactory prediction performance by our ABM, paving the way for more real-time decisions to be made for daily feed management on growing-finishing swine operations.

Undegradable dietary protein limits growth and carcass yields in crossbred Boer kids fed Desmanthus hay or Rhodes grass (Chloris gayana) hay supplemented with urea and/or cottonseed meal

Context Low-protein tropical forages required protein supplementation, which might affect growth of meat goats. Aims This study was aimed to compare liveweight gain, carcass/non-carcass yields and meat quality in crossbred Boer kids fed isonitrogenous diets varying in undegradable (UDP) and rumen-degradable (RDP) dietary protein sources. Methods Twenty-five female crossbred Boer kids were randomly allocated into the following five dietary treatments: Rhodes grass (Chloris gayana) hay supplemented with urea (U), urea plus cottonseed meal (UCSM), cottonseed meal (CSM), gliricidia (Gliricidia sepium) (Gliri) or Desmanthus (Desmanthus leptophyllus) only (Desman). The diets were formulated to supply 135 and 195 g crude protein/kg DM for the two experiments. Experiment 1 lasted 78 days and the dietary UDP:RDP ratio (g/kg DM) was 35:102 (U), 37:100 (UCSM), 40:97 (CSM), 55:82 (Desman) and 46:91 (Gliri). Experiment 2 lasted 138 days and the dietary UDP:RDP ratio (g/kg DM) was 45:150 (U), 52:143 (UCSM), 58:137 (CSM), 83:112 (Desman) and 71:124 (Gliri) respectively. Data were subjected to one-way ANOVA and general linear model. Key results After 138 days of supplementation, the Desman goats had the highest liveweight gain (83 g/day) and heaviest cold carcass weight (12.1 kg) in Experiment 2. This was followed, in descending order, by CSM (58 g/day and 9.6 kg), UCSM (48 g/day and 7.8 kg), Gliri (41 g/day and 7.6 kg) and U (6 g/day and 6.0 kg). Heavier carcass weight was associated with larger eye-muscle area and fat depth at the 12th rib. Aus-meat Beef Colour Standard scores of 3–4 for the eye muscle of the Desman and CSM goats compared with scores of 1C-2 in the other goats meant that the darker meat in Desman and CSM diets was associated with heavier carcass weight and a more rapid rate of decline in carcass pH. Conclusions Crossbred Boer kids fed high dietary UDP had higher intakes of UDP, RDP, metabolisable protein (MP) and metabolisable energy (ME), even though an isonitrogenous diet was offered. The Desman kids had higher liveweight gain, heavier carcass yield, greater eye-muscle area, thicker fat depth and heavier mass of non-carcass components. Implications The higher liveweight gain and carcass/non-carcass yields for Desman goats than for others was associated with increased DM, UDP, RDP, MP and ME intakes.

Heat Production of Iberian Pig Exposed to High Temperature and Effect of Dietary Supplementation with Betaine or Zinc.

The effect of heat, and dietary betaine or zinc on the heat production (HP) of Iberian pigs was studied. Thirty barrows (44 kg) were individually housed for 28 days and assigned to one of five treatments: (1) thermoneutrality (20 °C) and fed a control diet (TN-CON) ad libitum; (2) hot (30 °C) and fed a control diet (HT-CON) ad libitum; (3) thermoneutrality and pair fed a control diet (TN-CON-PF) to HT-CON; (4) hot and fed a betaine-supplemented (0.5%) diet (HT-BET) ad libitum; and (5) hot and fed a zinc-supplemented (0.012%) diet (HT-ZN) ad libitum. On the 18th day, pigs were moved to a respirometry chamber (two chambers) under their respective treatment. The metabolizable energy (ME) intake, HP and respiratory quotient (RQ) were measured over 24 h. No differences (p > 0.05) were found in HP and RE between treatments. For RQ, TN-CON was greater (p < 0.01) than HT treatments, except for HT-BET. All RQs indicated an overall lipogenesis where betaine supplementation showed an intermediate value, indicating that it may have a positive effect on lipogenesis and overall growth. At 30 °C, betaine or zinc had no effect on HP and RE; ME intake was not reduced, indicating a genetic adaptation of Iberian pigs to heat.

Effects of mung bean (Vigna radiat) haulm and concentrate supplementation on feed intake, body weight gain and carcass characteristics of Menz lambs fed on natural pasture hay

ABSTRACT Thirty-yearling Menz lambs with average initial body weight of 19.72 ± 1.96 kg (Mean ± SD) were used to evaluate the effects of supplementing mung bean haulms (MBH) and concentrate mixture (CM) on feed intake, body weight gain and carcass characteristics of lambs fed a basal diet of natural pasture hay. The lambs were assigned into five treatments in a randomized complete block design as follows: 226 CM (T1), 77 MBH + 192 CM (T2), 154 MBH + 156 CM (T3), 231 MBH + 120 CM (T4), 308 MBH + 87 CM (T5) grams on dry matter basis. Total dry matter (DM), organic matter and metabolizable energy intakes were increased (p < 0.05) with increasing levels of MBH inclusion in the diet. The DM digestibility of T5 was greater (p < 0.05) than T2. The crude protein intake was higher (p < 0.05) in T1 and T2. Average daily gain and carcass characteristics were similar (p > 0.05) among treatments. Feed conversion efficiency for T2 was higher (p < 0.05) than T4 and T5. This study supports the use of MBH as an alternative source of protein up to 308 g (77 g MBH + 192 g CM) for better FCE.

Performance, nutrient utilization and meat quality traits in Bos indicus cattle: a meta-analysis examining the effect of residual feed intake.

This meta-analysis aims to investigate the effects of residual feed intake (RFI) phenotype on performance, nutrient utilization and meat quality traits in Zebu (Bos indicus) cattle. Twenty-three peer-reviewed publications with 37 treatment means were included in the dataset. Weighted mean difference analysis compared animals categorized into low RFI (more efficient) versus medium or high RFI (less efficient) groups. Data heterogeneity via meta-regression and subgroup analysis, considering variables such as animal age, sex class, experimental duration, RFI group, dietary concentrate, and estimated metabolizable energy intake were also explored. The predominant genetic group of cattle in the dataset was Nellore (89.18%), followed by Brahman (10.81%). More efficient animals (low RFI phenotype) exhibited less dry matter intake (DMI; P < 0.010) than medium or high RFI animals (-0.95kg vs. -0.42kg/d). Cattle dietary crude protein and fiber digestibility were consistent across RFI groups (P > 0.05), while dietary ether extract digestibility tended to decrease (P = 0.050) in low RFI animals (-13.20g/kg DM). Low RFI animals tended to increased (P = 0.065) ribeye area (REA) compared to the high/medium RFI groups, while carcass backfat thickness (BFT) decreased (P = 0.042) compared to high/medium RFI groups. Moreover, there was an increase (P < 0.001) of 0.22kg in Warner-Bratzler shear force (WBSF) and a reduction (P < 0.001) in the myofibrillar fragmentation index (MFI) in low RFI animals. Meat color parameters (lightness [L*] and yellowness [b*]) and visual marbling scores were consistent (P > 0.05) across RFI groups. In conclusion, Zebu cattle classified as efficient (low RFI) exhibited reduced DMI, which improves their feed efficiency. However, BFT and meat quality parameters such as tenderness (WBSF and MFI) and redness [a*] were compromised by low RFI phenotype, highlighting the challenge of enhancing feed efficiency and meat quality traits in Zebu cattle.

Simulation of the nutritional requirements and energy balance of adult cows in a northern temperate grassland.

The forage-livestock balance is an important component of natural grassland management, and realizing a balance between the nutrient energy demand of domestic animals and the energy supply of grasslands is the core challenge in forage-livestock management. This study was performed at the Xieertala Ranch in Hulunbuir City, Inner Mongolia. Using the GRAZPLAN and GrazFeed models, we examined the forage-livestock energy balance during different grazing periods and physiological stages of livestock growth under natural grazing conditions. Data on pasture conditions, climatic factors, supplemental feeding, and livestock characteristics, were used to analyze the metabolizable energy (ME), metabolizable energy for maintenance (MEm), and total metabolizable energy intake (MEItotal) of grazing livestock. The results showed that the energy balance between forage and animals differed for adult cows at different physiological stages. In the early lactation period, although the MEItotal was greater than MEm, it did not meet the requirement for ME. MEItotal was greater than ME during mid-lactation, but there was still an energy imbalance in the early and late lactation periods. In the late lactation period, MEItotal could meet ME requirements from April-September. Adult gestational lactating cows with or without calves were unable to meet their ME requirement, especially in the dry period, even though MEItotal was greater than MEm. Adult cows at different physiological stages exhibited differences in daily forage intake and rumen microbial crude protein (MCP) metabolism, and the forage intake by nonpregnant cows decreased as follows: early lactation > mid-lactation > late lactation, pregnant cows' lactation > dry period. For the degradation, digestion and synthesis of rumen MCP, early-lactation cows were similar to those in the mid-lactation group, but both were higher than those in the late-lactation group, while pregnant cows had greater degradation, digestion, and synthesis of MCP in the lactation period relative to the dry period. For lactating cows, especially those with calves, grazing energy requirements, methane emission metabolism and heat production were highest in August, with increased energy expenditure in winter. Overall, grazing energy, methane emissions and heat production by dry cows were low. In the context of global climate change and grassland degradation, managers must adopt different strategies according to the physiological stages of livestock to ensure a forage-livestock balance and the sustainable utilization and development of grasslands.

Cajanus cajan and Lablab purpureus leaf meal-potential supplements over conventional protein sources for yearling Horro sheep fed a basal diet of fodder oat (Avena sativa) hay

A 90-day feeding trial with 25 yearling Horro lambs (22.6 ± 1.8 kg) was conducted from November 2022 to January 2023. The trial was designed to see how supplementing forage varieties of Cajanus cajan (Degagsa and Belabas) and Lablab purpureus (Beresa-55 and Gebis-17) affected the growth performance, feed intake and digestibility of Horro lambs fed a basal diet of fodder oat hay compared to conventional protein supplements. Five experimental sheep per treatment were arranged in a Randomized Complete Blocked Design to receive dietary treatments formulated on an iso-nitrogenous basis which was targeted to provide crude protein (CP) of 64.37 g/h/day. Data were taken on weight gain, feed conversion ratio, feed intake and refusal, and in-vivo digestibility features. All lambs were fed ad-libitum fodder oat hay containing 91.5 % Dry matter, 7.8 % ash, 6.4 % crude protein, 60 % neutral detergent fiber, 42.8 % acid detergent fiber, 13.4 % acid detergent lignin and 65 % in-vitro organic matter digestibility. The dietary treatments were fodder oat hay plus 280.8 g Gebis-17 variety (T1), 274.4 g Beresa-55 variety (T2), 320.9 g Belabas variety (T3), 329.3 g Degagsa variety (T4) and 300 g concentrate mixture (T5). The total dry matter intake (DMI) was higher in T3 and T4 than in the other treatment groups. Except for CP, nutritional consumption differed significantly across treatments. T3 and T4 had higher fiber intakes than the other treatments, while T2 had higher ash intakes and T5 had higher metabolizable energy intakes. Even though there was no significant variation in final body weight, lambs in T5 and T1 showed the greatest weight change and average daily gain. Although the diet in T5 induced the lamb performance in a manner comparable to that of the other dietary supplements, its inaccessibility and high cost would limit the use of such supplements by smallholder farmers. Thus, depending on their availability, either Lablab purpurues or Cajanus cajan varieties could be employed as feed supplements in the lambs` diet.

Effect of dietary inclusion of urea encapsulated in low-trans vegetable fat microspheres on fatty acids intake, carcass traits, quality, and fatty acid composition of lamb meat

This study evaluated the effect of including slow-release urea (SRU) coated from the low-trans vegetable fat (LTFV) microspheres in the diet of lambs on fatty acids intake, carcass traits, meat quality, and fatty acid composition of meat. Thirty-two non-castrated Santa Inês lambs (17.98 ± 2.01 kg of initial weight) were used in a randomized complete block design. Experimental treatments included a control which contained 5 g/kg urea (U0.5%) and three other treatments in which SRU (60% LTFV and 40% urea) was incorporated at 1.25% (SRU1.25%); 2% (SRU2.0%) and 3% (SRU3.0%) of total diet dry matter (DM). The inclusion of SRU in lamb diets increased linearly (P < 0.05) the intake of ether extract, metabolizable energy, and fatty acids. Carcass traits and physical-chemical composition of the Longissimus muscle were not changed by protected urea addition in lamb diet (P > 0.05). The addition of the protected urea in lamb diet linearly increased proportions of CLA and the 18:1 isomer (cis-12, cis-15, and cis-16) compared to U0.5%. There was a linear increase in branched-chain fatty acid (BCFA) content (P = 0.048) in Longissimus muscle due SRU inclusion. There were a quadratic increases for the sums of trans-MUFA (P = 0.003) and n-6 PUFA (P = 0.046) and total PUFA (P = 0.037) as SRU was added to lambs diet. Adding urea coated into low-trans vegetable fat microspheres increased the lamb intake of most FA and energy dietary, however, without affecting carcass traits and meat physicochemical composition. The inclusion of protected urea (SRU) in the lamb diet quadratically increases trans-MUFA, n-6 PUFA, and total PUFA concentrations in meat, and lambs fed with SRU at level 1.25% in DM total diet presented greater CLA and trans-MUFA concentrations compared free urea (U0.5%), which is beneficial from the point of view of the lipid quality of the meat and its relationship with consumer health.

Effect of energy level of pullet diet and age on laying performance and expression of hypothalamus-pituitary-gonadal related genes in laying hens

Dietary energy density influences feed intake (FI) and development of layer-type pullets. A total of 384 nine-wk-old Hy-Line Brown pullets were randomly assigned to one of 3 dietary treatments: fed a diet with 2,600, 2,750, and 2,900 Kcal metabolizable energy/kg (ME/kg) from 10 to 21 wk of age. The results showed that the 2,900 and 2,600 ME groups had lower feed and ME intake (P < 0.01) from 10 to 21 wk of age. The 2,600 ME pullets had heavier body weight (BW) and longer shank length (P < 0.05) at 21 wk of age than the 2,750 ME group. The eggshell percentage was increased by the 2,600 and 2,900 kcal/kg treatments (P = 0.002). Serum concentration of 17-β-estradiol (E2), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) decreased at 70 wk of age (P < 0.05). Pullet diet and its interaction with age had a significant influence (P < 0.001) on the expression of gonadotropin-releasing hormone 1 (GnRH-1) and gonadotropin-inhibitory hormone (GnIH) in the hypothalamus and of gonadotropin releasing hormone 1 receptor (GnRH-1R) and gonadotropin-inhibitory hormone receptor (GnIHR) in the pituitary. In the hypothalamus, GnRH-1 expression increased from 9 to 40 wk of age and then decreased; however, GnIH expression was highest at 70 wk of age. Follicle-stimulating hormone receptor (FSHR) expression increased (P < 0.001) at wk 40 and decreased at wk 70 compared to wk 21 at various follicular stages. In conclusion, the energy level of pullet diet had no unfavorable influence on feed intake, laying rate, egg mass, and FCR, whereas change egg weight and mortality during the laying period from 21 to 70 wk of age. during the laying period. These results suggest that pullet dietary energy can activate the expression of genes related to reproduction in the hypothalamus, whereas it plays a minor role in the regulation of genes in the pituitary and ovary. Age-induced gene expression in the hypothalamus-pituitary-gonadal (HPG) axis is associated with laying performance in 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.

10 Effects of different feeding levels during gestation on gilt reproductive performance during the first lactation

Abstract Our objective was to determine the effects of different feeding levels for gilts during gestation on reproductive performance during the first lactation. A total of 1,187 PIC Camborough gilts were used. Gilts were randomly allotted in a randomized complete block design based on breeding week, body weight (BW), and age to one of four treatments differing in daily metabolizable energy (ME) intakes per day during gestation. Gilts were housed in stalls throughout the entire gestation and individually fed with a gestation diet containing 2.95 Mcal of ME/kg via feed boxes that were weekly calibrated. Treatments consisted of 1) 5.0 Mcal of ME/d (1.7 kg feed/d) throughout the entire gestation; 2) 5.9 Mcal of ME/d (2.0 kg feed/d) throughout the entire gestation; 3) 6.8 Mcal of ME/d (2.3 kg feed/d) throughout the entire gestation; and 4) 5.0 Mcal of ME/d (1.7 kg feed/d) from breeding until d 90 of gestation, and then 5.9 Mcal of ME/d (2.0 kg feed/d) from d 90 to d 112 of gestation. Gilt was the experimental unit and data were analyzed using generalized linear mixed models with the lmer and glmer functions of R. There was no evidence (P &amp;gt; 0.10) for treatment differences on gilt BW and age at breeding, with gilts averaging 156.7 kg at 210 d of age (Table 1). Gilts receiving 6.8 Mcal of ME/d during gestation were heavier (P &amp;lt; 0.05) at farrowing compared with all other treatments; however, these gilts lost (P &amp;lt; 0.05) more BW during lactation. Gilts receiving 5.0 Mcal ME/d throughout the entire gestation had less (P &amp;lt; 0.05) maternal net BW gain from breeding to weaning compared with gilts receiving 6.8 Mcal ME/d. Gilts receiving 6.8 Mcal of ME/d gained more (P &amp;lt; 0.05) caliper scores (CS) from breeding to d 90 of gestation compared with gilts receiving 5.0 Mcal ME/d. Regardless of feeding level, gilts lost an average of 0.85 CS from d 90 to d 112 of gestation. Overall, gilts receiving 6.8 Mcal of ME/d gained more CS during gestation, but lost more CS during lactation (P &amp;lt; 0.05). There was no evidence for differences in gilt backfat depth measurements (P &amp;gt; 0.10). Gilt feeding levels did not impact (P &amp;gt; 0.10) total piglets born, percentage sillborn, or percentage of mummified fetuses. Gilts receiving 5.0 Mcal of ME/d had greater (P &amp;lt; 0.05) percentage piglets born alive compared with gilts receiving 5.9 Mcal of ME/d, with other treatments intermediate. There was no evidence (P &amp;gt; 0.10) for treatment differences in average piglet BW, average piglet daily gain during lactation, piglet mortality from cross foster to weaning, or wean to estrus interval in the next cycle. In summary, increasing energy intake of gilts during the first gestation did not impact reproductive performance during the first lactation, but gilts receiving 5.0 Mcal of ME/d throughout the entire gestation had less maternal net BW gain.

Effects of refused melon fruit in Canarana grass ensilage on intake, digestibility, serum biochemistry, performance, carcass characteristics and meat attributes of feedlot lambs.

Ensilage of refused fruit with forage is a viable approach to increase resource use in ruminant feed. The objective of this study was to investigate the impact of ensiling refused melon fruit (RMF) with Canarana grass on the intake, apparent digestibility, serum biochemistry, performance, carcass traits, and meat attributes of feedlot lambs. Four distinct silage treatment types were prepared by ensiling RMF at 0g/kg (control), 70g/kg, 140g/kg, and 210g/kg (as fed) with Canarana grass. Twenty-eight male Santa Inês lambs (7 lambs per treatment), initially weighing 22.3 ± 1.0kg at 120 days of age, were distributed in a completely randomized design and confined for a total of 96 days, including a 23-day adaptation period and 73 experimental days in a feedlot. The lambs received the treatment-silage in diets as a complete mixture with a roughage: concentrate ratio of 30:70. The inclusion of RMF in Canarana grass ensilage decreased (P < 0.05) the lambs' intake of dry matter, crude protein and metabolisable energy. The inclusion of RMF in ensilage had a quadratic effect (P < 0.05) on the digestibility of non-fibrous carbohydrates. The serum total protein and cholesterol levels decreased (P < 0.05) with the inclusion of RMF in the ensilage, but we observed no effect on the final weight and average daily gain of the lambs. The feed efficiency increased (P < 0.05) by including RMF in the Canarana grass ensilage. The RMF in the ensilage did not influence cold carcass weight and yield. The fat content of the meat decreased (P < 0.05) with the inclusion of RMF in the ensilage. It is recommended the inclusion of up to 210g/kg of RMF in Canarana grass ensilage to increase feed efficiency and avoid impacts on the performance and carcass attributes of confined lambs.

Lactation performance, feed efficiency, and blood metabolites of dairy cows treated with recombinant bovine somatotropin: A systematic review and meta-analysis

A systematic review and meta-analysis were conducted to assess the impact of recombinant bovine somatotropin (rbST) on lactation performance, feed efficiency, and blood metabolites in dairy cows. In the systematic review, articles were selected based on the following criteria: (1) Data focusing on the influence of bovine somatotropin doses on milk production; (2) Submission of original data; (3) Articles published in journals; and (4) Articles in English or Portuguese. The analysis of variance was used with a completely randomized design and mixed models methodology. Polynomial regression was applied to significant fixed effects (rbST dose). The use of rbST resulted in increased milk yield and 4% fat-corrected milk yield, while fat, protein, and lactose contents remained unaffected. Dry matter and metabolizable energy intakes, as well as milk/feed efficiency, exhibited a linear increase, but body condition score (BCS) was negatively impacted. The administration of rbST led to higher blood concentrations of triglycerides and insulin. Cows treated with rbST showed a 23% increase in non-esterified fatty acid (NEFA) concentrations compared to non-treated cows. Additionally, growth factors IGF-1 and IGF-2 displayed a linear increase with rbST treatment. In summary, rbST administration increased milk yield and fat-corrected milk yield without affecting milk components. However, despite increasing intake, it resulted in BCS losses and alterations in blood parameters such as NEFA, IGF-1, and IGF-2.

Effect of dietary methionine to crude protein ratio on performance of Ross 308 broiler chickens aged 22 to 42 days

An experiment was conducted to determine the effect of dietary methionine to crude protein (CP) ratio on the performance of male Ross 308 broiler chickens aged 22 to 42 days. The diets were isocaloric and isonitrogenous but with different methionine-to-CP ratios. The diets, based on methionine to crude protein ratios, were M0.020 (0.020), M0.025 (0.025) M0.030 (0.030), M0.040 (0.040), or M0.045 (0.045). A complete randomized design was used. A quadratic type of equation was used to determine dietary methionine to CP ratios for optimal performance of the chickens. Dietary methionine to CP ratio had no effect (P > 0.05) on feed intake, live weight gain, live weight, feed efficiency, metabolizable energy intake, nitrogen retention, abdominal fat pad weight, breast meat nitrogen and methionine contents, and meat flavour and shear force values of the chickens, but it affected (P < 0.05) CP digestibility, carcass and breast weights, and breast meat tenderness and juiciness. Methionine to CP ratios of 0.039, 0.038, 0.050, and 0.050 were calculated to result in optimal CP digestibility, carcass weight, breast meat tenderness, and juiciness, respectively. These results may imply that dietary methionine to CP ratio requirements for broiler chickens will depend on the production parameter of interest.

Can the Inclusion of Forage Chicory in the Diet of Lactating Dairy Cattle Alter Milk Production and Milk Fatty Acid Composition? Findings of a Multilevel Meta-Analysis.

In traditional ryegrass/white clover (Lolium perenne L./Trifolium repens L.) pastoral systems, forage herbs such as chicory (Cichorium intybus L.) present an opportunity to fill feed deficits during late spring and summer. Although multiple research publications have evaluated the efficacy of chicory for enhancing milk production and milk fatty acid (FA) profile, no publication has quantitatively synthesised the body of research. This systematic review and meta-analysis examined the effect of chicory on milk production and composition, as well as on the milk fatty acid composition of dairy cattle. A total of 29 comparisons from 15 unique research publications involving 597 dairy cattle were used to develop a dataset for analysis. Three-level random-effect and robust variance estimator models were used to account for the hierarchical structure of the data and the dependency of effect sizes within publications. Chicory inclusion increased milk yield when compared to grass-based diets {weighted mean difference (WMD) = 1.07 (95% CI 0.54-1.60) kg/cow/d, p < 0.001}, but it provided a similar milk yield when compared to other forages such as legumes and herbs {dicots; WMD = -0.30, (95% CI -89-0.29) kg/cow/day, p = 0.312}. Increases in milk yield were congruent with differences in DM intake (p = 0.09) and ME intakes (p = 0.003), being similar in chicory-fed and dicot-fed cows but higher than grass-fed cows. Chicory feeding's effect on milk solids was twice as high during mid lactation {154 days in milk; WMD = 0.13, (95% 0.081-0.175) kg/cow/day, p < 0.001} as during late lactation {219 days in milk; WMD = 0.06, (95% 0.003-0.13) kg/cow/day, p = 0.041}. In line with milk yield, greater and more significant effect sizes were found for alpha linolenic acid {ALA; WMD = 0.20 (95% CI 0.06-0.35) g/100 g FA, p = 0.011} when chicory was compared to grass species only. Comparing chicory with dicots suggests that chicory inclusion did not impact ALA concentrations {WMD = 0.001 (95% CI -0.02-0.2) g/100 g FA, p = 0.99}. There were no differences in conjugated linoleic acid concentration in the milk of cows fed chicory or control diets. The study provides empirical evidence of chicory's efficacy for improved milk production and milk fatty acid composition.

Effect of supplementing concentrate mixture with field pea hull on yearling ram lambs of local sheep: Nutrient intake, linear body measurements, and changes in body weight

The fattening of sheep has been recognized as a potentially profitable activity in the highlands of Ethiopia. However, feed shortage and increasing prices for conventional feed ingredients and commercially formulated concentrate mixtures critically affect the fattening practice of sheep in the country. So, this feeding trial was conducted to evaluate the effect of feeding field pea hull at different inclusion levels with a concentrate mixture on feed intakes, nutrient utilization, linear body measurements, and body weight gain. Eighteen yearling ram lambs were randomly allocated to three dietary treatments using a randomized complete block design. The dietary treatments were T1 (control), fed native hay adlibitum + concentrate mixture formulated using only conventional feed ingredients (0% field pea hull); T2 and T3 were fed native hay adlibitum + concentrate mixture formulated with inclusion of 35% field pea hull and 50% field pea hull, respectively along with other feed ingredients. The feeding trial was conducted for 90 days. Data were analyzed using GLM procedures of SAS, and Turkey’s HSD multiple-comparison was used for means separation. The result showed a significant (p&lt;0.001) variation in dry matter and nutrient intake among treatments. The DMI was the highest in T3, followed by T2, while it was the lowest in T1. The average total neutral detergent fiber and acid detergent fiber intakes and metabolizable energy intake were highest in T3 and followed by T2, while they were the lowest in T1. The average total body weight gain (kg) was higher in T3 (9.0kg) and T2 (8.67kg) than in T1 (6.58kg). Similarly, higher average daily body weight gains were recorded in T3 (100g) and T2 (96.3g) than in T1 (73.2g). Sheep that were fed field pea hull by the inclusion of 50 % in concentrate mixtures (T3) were more efficient in feed utilization (p&lt;0.05) than T1 as they consumed significantly less amount of feed per 1 g of body weight gain. Hence, it is concluded that feeding of 50% field pea hull along with concentrate mixture could be used for better fattening performance of sheep.