Dry Matter Intake In Relation Research Articles

Exogenous enzymes in sheep diet: nutritional and physiological parameters

The objective of this study was to evaluate the effect of adding exogenous enzymes to the diet on nutrient intake and digestibility, nitrogen balance, ingestive behavior and rumen movement of ewe lambs. Five ewe lambs, Dorper x Santa Inês crossbred, with an average age of 7 ± 1 months, average weight of 36.40 ± 2.36 kg were assigned in a 5x5 Latin square design. The treatments consisted of adding exogenous enzymes to the concentrate: Allzyme, Fibrozyme®, Amaize®, Mix and Control. Analyses of variance were applied and means were compared by the SNK test, and non-parametric Kruskal Wallis test at 5% significance. The dry matter intake in relation to body weight, crude protein intake and nitrogen intake were higher with the use of amylolytic enzyme compared to the other treatments (p <0.05). Nitrogen balance was higher with the use of amylolytic enzymes and the Allzyme® enzyme complex (p <0.05). A longer time spent in total chewing was observed with the inclusion of fibrolytic and amylolytic enzymes without changes in rumen movement. The use of exogenous enzymes promotes better use of nutrients, with high digestibility of dry matter, neutral detergent fiber and crude protein.

Feeding value of supplemental fat as a partial replacement for steam-flaked corn in diets for Holstein calves during the early growing phase.

In calf-fed Holstein steers, the early growing phase is characterized by very high relative dry matter intake (DMI) accompanied with lower-than-expected efficiency of energy utilization. Although fat is commonly supplemented in growing–finishing diets, the comparative feeding value has not been investigated during the initial receiving–growing period. Eighty-four Holstein calves (127.7 ± 2.1 kg body weight) were used to evaluate the effects of including 3.5% of supplemental yellow grease (YG) in the diet on characteristics of growth performance and dietary energy utilization of calves during the early growth phase. Morbidity and mortality were not affected by dietary treatments. Yellow grease supplementation did not affect DMI, but tended to increase average daily gain (4.6%; P = 0.07), and increased (P ≤ 0.03) gain efficiency (5.8%) and dietary net energy for maintenance (NEm) and gain (NEg) by 4.1% and 5.3%, respectively. Based on performance data, the estimated NE value of supplemental YG was 4.67 and 3.68 Mcal/kg for NEm and NEg, respectively. These values are consistent with current tabular values assigned for vegetable oils (4.75 and 3.51 Mcal/kg), but markedly less (16.6%) than NEm value assigned for YG (5.60 Mcal NEm/kg; NASEM, 2016. Nutrient requirements of beef cattle. 8th ed. Washington (DC): National Academy Press.).

Phytol supplementation alters plasma concentrations of formate, amino acids, and lipid metabolites in sheep

The phytol moiety in chlorophyll molecules acts as an agonist of peroxisome proliferator-activated receptor-α in monogastric animals. The current study aimed to clarify the effects of dietary supplementation with phytol on the plasma concentrations of formate and amino acids related to one-carbon (1C) donors and its effects on lipid metabolism in sheep. Four mature sheep were fed with a mixed ration (metabolizable energy, 10.7 MJ/kg DM; CP, 150 g/kg DM) comprising barley, rice bran, soybean meal, and oat hay at 1.5 times maintenance metabolizable energy for three consecutive 14-day experimental periods. The first and third periods served as controls without phytol supplementation, while in the second period, phytol was added to the mixed ration at 12 g/kg of dietary DM per day. In each period, feces, urine, and jugular blood samples were collected. Dry matter intake in relation to metabolic BW was slightly lower (P < 0.01) in the first period than the second and third periods but did not differ between the latter two periods. Dry matter digestibility was slightly reduced (P = 0.05) by the phytol treatment. Nitrogen (N) intake and retention showed similar trends to DM intake, but urinary N was unchanged among the periods. Plasma cholesterol and phospholipid concentrations decreased during the phytol treatment period, while triglyceride concentration increased (P < 0.05). In the phytol treatment period, the plasma concentrations of serine and glycine (1C donors) increased, but the glutamate level decreased (P < 0.01). Plasma concentrations of formate and methionine increased (P < 0.01) from the first control period to the phytol supplementation period, but homocysteine and cysteine (intermediate and by-product of the methionine cycle) levels were unchanged among the treatment periods. In conclusion, dietary phytol affects lipid metabolism as well as amino acid metabolism and 1C donors in sheep. These effects may be associated with the activity of phytol as an agonist of the nuclear receptors, although this needs further investigation.

Water and food utilization efficiencies in sheep and their relationship with some production traits

• The use of water by sheep needs more attention from researches and sheep breeders. • Residual water intake (RWI) is a new trait for sheep selection. • Residual feed and residual water intake is a new trait for sheep selection. • Sheep more efficient in water use are more efficient in food use. • Sheep more efficient in water and food use are desirable in a sustainable industry. The objective of this study was evaluate the efficiency in water and food use in sheep production, using two new traits (residual water intake - RWI; residual feed and residual water intake - RFRWI). For this purpose, we evaluated the relationships between the traits total water intake, RWI and RFRWI with water measures, productive performance and carcass traits (ultrasound). We used 32 lambs with age of 3 months: 16 Santa Ines breed (8 males and 8 females) and 16 crossbred 7/8 Dorper x Santa Ines (8 males and 8 females). They were fed at an automated feed and water station (Intergado®), where the food and water intake by each animal was measured automatically. Residual water intake (RWI), residual feed intake (RFI) and residual body weight gain (RWG) were calculated using the MIXED procedure in SAS®. Correlation coefficients between total water intake (TWI), RWI and all traits (water measures, performance and carcass traits) were calculated using the CORR procedure (P ≤ 0.05). Total water intake showed mean 3.15 L/day during the study and the RWI ranged from 0.66 L to -0.89 L, which represents a difference of 1.55 L between the most and least efficient animal. There was positive correlation between less efficient animals in water consumption (positive RWI) and water intake (r = 0.31); total water intake in relation to dry matter intake (r = 0.36); total water intake in relation to mid-trial metabolic body weight (r = 0.26); residual feed and residual water intake (r = 0.99) and gain/feed ratio (r = 0.44). There was negative correlation between less efficient animal and dry matter intake in relation to body weight (r= -0.33) and feed conversion ratio (r= -0.44). The evaluation of the new variables, RWI and RFRWI, proved effective in identifying the most efficient animals in water use. Moreover, these findings open the possibility of considering the traits RWI and RFRWI in sheep selection, because performance and carcass traits are not adversely affected by selecting for these new traits.

Dry matter intake and milk yield of cows grazing Xaraés palisadegrass under different management strategies

This study aimed to evaluate the intake and milk yield of crossbred cows (Holstein x Zebu), under two management strategies, based on 95% light interception and fixed days. Eight lactating cows with body weight of 466 kg (± 35 kg) and lactation stage of 137 days (± 107 days) were used, four animals were assigned to each treatment. Dry matter intake was estimated indirectly, using neutral detergent insoluble fiber as internal indicator and chromium oxide as external indicator. This was a completely randomized design, with four replications, two grazing strategies and three days of occupation. The animals under light management showed dry matter intake on the first day (11.42 kg) similar to the second day (9.57 kg), and this was similar to the third day (7.06 kg), but the intake on the first day was greater than on the third day. On the fixed days, intake did not differ between the first and second day (12.05 and 11.47 kg, respectively), and intake of the third day (6.70 kg) was lower than in the first two days. The dry matter intake in relation to the body weight of the animals presented similar results to the dry matter intake of forage in kilos, which can be explained by the small difference in weight between the mean of the groups. The individual milk yield showed a similar behavior among the grazing strategies for the days of occupation, which increased from the first to the second day (12.49 to 13.88 kg) and decreased from the second to the third day (12.20 kg). Grazing management strategies did not promote differences in the performance traits of lactating cows. The day of grazing during the period of occupation can be decisive for intake and production.

Inclusion of licuri meal in the diet of pasture dairy cows.

The objective of this study was to evaluate the inclusion of increasing levels of licuri meal as a substitute for soybean bran in the diet of pasture-based dairy cows and its effects on the intake, nutrient digestibility, and milk production and composition. Eight crossbred Holstein/Zebu cows were used in two 4 × 4 Latin square plots. The diets contained increasing percentage of licuri meal (0.0, 4.16, 7.09, and 9.45%) in the total diet, replacing soybean bran. The inclusion of licuri meal in the diet affected total dry matter intake and dry matter intake in relation to body weight, which presented a quadratic effect. The same behavior was observed for the consumption of EE, CP, TDN, and NDFap. The NFC consumption showed a linear decrease with the addition of the by-product in the diet. There was no influence of the inclusion of the licuri meal on the digestibility of the DM, CP, NFC, and TDN, while the digestibility of the NDFap and EE presented increasing linear effect. There was a reduction of milk production and food efficiency with the inclusion of increasing levels of the meal. The fat content in milk showed a linear increasing effect. Ditto for cholesterol. It is recommended to include not more than 7.00% of licuri meal for lactating cows with an average production of 20kgday-1.

Growth performance and safety of meat from cattle feedlot finished with monensin in the ration

Monensin is an ionophore antibiotic, the inclusion of which in the feed of beef cattle favors the best use of feed nutrients, via ruminal modulation. However, there are concerns regarding the residence of residues in the carcass from metabolism of monensin. The objective of this study was to evaluate the productive performance, carcass characteristics, serum parameters, tissue residual depletion and economic benefit of finishing of young bulls in confinement with monensin in the ration. Thirty-six animals were confined, and given 50% corn silage feed and 50% more concentrated feed. The experimental design was completely randomized, with two treatments (with or without monensin) and 10 replicates for the control group and eight for the monensin group. The use of monensin reduced the dry matter intake in relation to live weight (2.36% vs 2.55%), and improved feed conversion (8.61 vs 10.06 kg kg?1); the animals presented higher live weight (511 vs 494 kg), higher warm carcass weight (285 vs 272 kg) and an increase in fat thickness (4.97 vs 4.25 mm) compared to control animals. These increases in performance gave higher economic results, with a profit margin of R$ 122.84 per animal. A waiting period of 16 h before slaughter resulted in monensin concentrations below 0.25 µg kg?1 in edible organs and tissues, values well below those permitted by legislation. The use of monensin for young bulls in confinement promoted improvements in productive and economic performance, without leaving residues in edible tissues.

Hay quality and intake by dairy cows. 2. Predicting feed intake with consumer-demand models

Daily food intake is the single most important factor affecting milk production by dairy cows. However, an animal’s choice of food depends not only on the nutritional characteristics of the food in question, but also on the nutritional characteristics of other available foods. Any prediction of intake should be based on the nutritional characteristics of all foods on offer. However, when the initial food-preference experiment possesses a control-specific design (i.e. experiments that include only a limited number of control foods for comparison) it is apparent that the prediction of future food choices must include the same controls as the initial experiment underpinning the prediction model. This requirement is clearly impractical. By drawing an analogy between animal food preference and economic choice, the total and relative dry matter intake of two oaten hays was modelled on their nutritive characteristics by estimating a consumer-demand model (here a generalised additive model representation of a direct bundle good model) from experimental data offering hays to lactating cows (adj-R2 &gt; 80%; where adj-R2 is the value adjusted for the number of predictor terms in the model). To negate the problem of control-specificity, a simplex interpolation was developed to construct and test predictions of hay intake for a second food-preference experiment (adj-R2 &gt; 53%; correlation between predictions and actual intakes = 76%). To improve prediction accuracy and avoid control-specificity, it is recommended that future preference experiments be designed to exclude control-specificity by mimicking fractional factorial designs, supported by a two-stage approach to select a cost-effective number of comparisons. Our approach to predicting food intake may be extended to a choice between more than two foods, and to combinations of foods other than oaten hays.

Optimizing protein intake as a foraging strategy to maximize mass gain in an omnivore

Energy maximization, time minimization, and linear programming models subject to various constraints have dominated foraging ecology ideas and methods for decades. However, animals must use very complex physiological processes and foraging decisions to ensure fitness that in many cases may not be adequately described by these approaches. An example of this problem occurs when brown bears, Ursus arctos, have access to both abundant salmon and fruit. Salmon are one of the most energy and nutrient dense foods available to bears. Fruits are often high in soluble carbohydrates, low to deficient in many required nutrients, and more difficult to efficiently exploit. Therefore, wild brown bears that fatten primarily on fruits without access to salmon are 50% smaller than salmon‐feeding bears. Thus, we predicted based on a linear, energy‐maximizing model without dietary interaction effects that wild brown bears with access to both abundant salmon and fruit would feed almost exclusively on salmon. However, wild adult females with or without accompanying offspring foraged three times longer per day on fruit than on salmon. Similarly, the relative dry matter intake of ad libitum apples and salmon by captive, adult brown bears averaged 76±5% fruit and 24±5% salmon. Captive brown bears consuming mixed diets with intermediate dietary protein levels had 60% lower maintenance energy costs, 37% to 139% higher efficiencies of mass gain, and 72% to 520% higher maximum rates of gain than when they consumed either salmon or fruit alone. These relationships were nonlinear functions of dietary protein content in which salmon and fruit provided complementary nutritional resources. Both wild and captive bears attempted to regulate total protein, energy, and carbohydrate intake within a multidimensional intake target that both maximized energy intake and mass gain.

Fluid and particle retention times in the black rhinocerosDiceros bicornis, a large hindgut-fermenting browser

The mean retention time (MRT) of ingesta in the gastrointestinal tract is one of the major determinants of herbivore digestive physiology. We examined MRTs of fluids and particles in the gastrointestinal tract of six adult captive black rhinocerosesDiceros bicornis on conventional zoo diets. Fluid MRT ranged from 25–45 h and averaged 31 h. Particle MRT ranged from 28–59 h and averaged 38 h. In the six animals, both fluid and particle MRT declined as relative dry matter intake (g/kg metabolic body mass) increased. Black rhinoceroses, which are large hindgut-fermenting browsers, retained ingesta for a shorter period relative to their body size than grazing equids or grazing rhinoceros species. Our findings support the hypothesis that browsing hindgut fermenters have relatively shorter MRTs than grazing hindgut fermenters.

Dietary energy losses of cattle influenced by body type, size, sex and intake

ABSTRACTDigestibility (DE) and metabolizability (ME) of a single pelleted diet was examined with growing Angus and Holstein cattle. One hundred and ninety-one individual digestion trials were conducted with bulls, steers and heifers. Food was offered ad libitum or restricted with a daily meal frequency of four. Data were analysed by two covariate models. The first included relative dry matter intake (RDMI) defined as the ratio of DMI to body weight (M0·73). In the second model, covariates were defined by genetic-size scaling; the first covariate scaled DMI by mature weight (A) raised to the power 0·73 (DMI/A0·73) and the second covariate was degree of maturity (μ) defined as body weight divided by A. Model 2 also allowed separation of size and DMI effects. No breed differences were detected. There was a consistent trend for increasing ME and ME/DE from heifers to steers to bulls which was significant between heifers and the average of bulls and steers (575·3 v. 589·3 and 832·8 v. 844·3 J/kJ for ME and ME/DE, respectively). Independent of animal effects, DE, ME and urinary energy (UE) decreased and ME/DE and faecal energy (FE) losses increased as RDMI or DMI/A0·73 increased. Per unit rise in RDMI equivalent to maintenance, the corresponding changes for DE, ME, ME/DE, FE and UE were –33·9, –13·6, 21·3, 34·1 and 9·6 J/kJ, respectively. DE increased 1·5 and ME increased 0·8 J/kJ GE for each 01 unit increase in degree of maturity.

Studies on nitrogen metabolism in rats of different age fed on a protein-free diet. 2. The feed intake.

Changes in the intake of dry matter (DM) of the protein-free diet (PFD) fed ad libitum were studied on male rats in relation to the shrunk body mass (SB) and duration of protein-free feeding (t). The intake of DM and changes of SB were investigated on the same rats and during the same experimental periods. The mean intake of DM in relation to PFD feeding periods t = 3, 6, 9, 12, 16 days and the daily DM intake (DMd) in relation to the daily shrunk body mass (SBd) were calculated on logarithmical values according to a model of linear regression y = a + bx and to a model of multiple regression y = b0 + b1x1 + b2x2. The rate of DM intake in relation to the duration of PFD feeding (t) did not differ significantly between age groups (k = 14) but the ak differed significantly. The common coefficient bc = 0.871 +/- 0.012 was less than 1***. This relationship is described by the equation: DM intake = Ak X t0.871, where: DM intake = the sum of intake in the periods of 3, 6, 9, 12 and 16 days (in grams), k = age group, t = PFD feeding period. No significant correlation (P less than 0.05) was found between bk and the initial body mass (SBi) or age of rats (r = -0.21 and -0.02, respectively) but between ak and SBi or age the correlation was highly significant (r = 0.960 and 0.832). This indicates that the amount but not the rate of DM intake depended on the initial body mass or age. The relation between DMd and SBd, the latter increasing with age but decreasing with the duration of PFD feeding, is described by equation: DMd intake = Ad X SBd0.503, where: DMd intake in grams, d = day 1 to 15 of PFD feeding, SBd = daily shrunk body mass in kilograms. The values of Ad decreased with the duration of PFD feeding. The using of multiple regression permitted to describe DMd intake as a function of SBd and (d) by a common equation: DMd intake = 27.02 X SBd0.503 X d-0.103; R = 0.976. Thus the daily DM intake was closely positively correlated with SBd and negatively correlated with the duration of protein-free feeding regardless of the age of rats.(ABSTRACT TRUNCATED AT 400 WORDS)