Net Energy Basis Research Articles

Using caloric efficiency to estimate the net energy value of expelled, extruded soybean meal relative to dehulled, solvent-extracted soybean meal and its effects on growth performance of nursery pigs.

This study aimed to estimate the net energy (NE) value of expelled, extruded soybean meal (MSBM) relative to dehulled, solvent-extracted soybean meal (SSBM) and determine its effects on growth performance of late nursery pigs. A total of 297 pigs (DNA 241 × 600) were weaned (BW 5.10 kg) and placed into 60 pens (2 rooms of 30 pens) with 5 pigs per pen balanced by gender and weaning weight. Pigs were fed a common diet for 21 d. Then, pens of pigs (BW 9.3 kg) were randomly assigned to one of five treatments to provide 12 replications per treatment. Treatments consisted of increasing amounts of MSBM replacing SSBM in the diet (0%, 25%, 50%, 75%, and 100%). All diets were fed for 28 d and were formulated to 1.30% standardized ileal digestible lysine and met or exceeded requirements for amino acids, calcium, and phosphorus. The SSBM diet was formulated to 2,421 kcal/kg and NE was not balanced between diets. Analyzed values for CP, EE, CF, and total lysine for the SSBM were 47.28%, 0.47%, 3.80%, and 3.00%, whereas the MSBM contained 47.41%, 6.88%, 5.32%, and 2.99%, respectively. The MSBM had increased values for KOH solubility and trypsin inhibitor (83.62% and 7,026 TIU/g) compared to the SSBM (73.05% and 3,011 TIU/g), whereas urease activity was similar between the two (0.03 and 0.02 Δ pH, respectively). Data were analyzed using Proc GLIMMIX (SAS 9.4; Cary, NC) with pen as the experimental unit and room as the blocking factor. There was no evidence of differences in ADG and ADFI in pigs fed diets with increasing concentrations of MSBM. Pigs fed diets with increasing concentrations of MSBM had improved (linear, P < 0.001) G:F and caloric efficiency on an NE basis. Using caloric efficiency to estimate NE of the MSBM relative to SSBM, MSBM was estimated to have a value of 2,566 kcal/kg. In conclusion, MSBM contains approximately 123% of the energy of SSBM, which improved feed efficiency when fed to nursery pigs.

31 Using Caloric Efficiency to Estimate the Energy Value of Expelled, Extruded Soybean Meal Relative to Dehulled, Solvent-extracted Soybean Meal and Its Effects on Growth Performance of Nursery Pigs

Abstract This study aimed to estimate the net energy value of expelled, extruded soybean meal (MSBM) relative to dehulled, solvent-extracted soybean meal (SBM) and determine its effects on growth performance of late nursery pigs. Analyzed values for CP, EE, CF, and lysine for the SBM were 47.28%, 0.47%, 3.80%, and 3.00% while the MSBM contained 47.41%, 6.88%, 5.32%, 2.99% respectively. A total of 297 pigs (DNA 200 x 400) were placed into 60 pens (2 rooms of 30 pens) with 5 pigs per pen balanced by gender and weaning weight. Pigs were fed common diets for 21 days. Then, pens of pigs (BW 9.3 kg) were randomly assigned to one of five treatments to provide 12 replications per treatment. Treatments consisted of increasing amounts of MSBM replacing SBM in the diet (0, 25, 50, 75, 100%). All diets were fed for 28 days and were formulated to 1.30% standardized ileal digestible lysine and met or exceeded NRC (2012) recommendations for lysine:amino acids, calcium, and phosphorus. The SBM diet was formulated to 2421 kcal/kg and net energy (NE) was not balanced between diets. Data were analyzed using Proc GLIMMIX (SAS 9.4; Cary, NC) with pen as the experimental unit and room as the blocking factor. There was no evidence of differences in ADG and ADFI in pigs fed diets with increasing concentrations of MSBM. Pigs fed diets with increasing concentrations of MSBM had improved (linear, P &amp;lt; 0.001) G:F and caloric efficiency on an NE basis. In conclusion, using caloric efficiency to estimate NE of the MSBM relative to SBM, MSBM was estimated to have a value of 123% of SBM NE or 2566 kcal/kg. This increase in NE resulted in improved feed efficiency of nursery pigs.

The effects of soybean hulls level, distillers dried grains with solubles, and net energy formulation on nursery pig performance.

Four experiments were conducted to investigate the effects of increasing dietary soybean hulls without or with distillers dried grains with solubles (DDGS) and net energy (NE) formulation on nursery pig performance. In experiment 1, a total of 210 nursery pigs (initially 6.6 ± 0.1 kg) were used in a 34-d study. Pigs were fed one of five diets that contained increasing soybean hulls (0%, 5%, 10%, 15%, and 20%). Diets were not balanced for NE. Increasing soybean hulls decreased (linear, P < 0.01) average daily gain (ADG) and gain:feed ratio(G:F), and tended to decrease average daily feed intake (ADFI; quadratic, P < 0.10). In experiment 2, 210 nursery pigs (initially 13.6 ± 0.1 kg) were used in a 20-d study to determine the effect of equal NE formulation in diets with soybean hulls. Pigs were fed one of five diets containing 0% (control), 10%, or 20% soybean hulls either balanced to contain equal NE to the control diet or not balanced for energy. Diets containing 10% and 20% soybean hulls with balanced NE contained 3.60% and 7.15% added soybean oil, respectively. Increasing soybean hulls decreased (linear, P < 0.01) ADG regardless of formulation method. Pigs fed increasing soybean hulls without added fat had decreased (linear, P < 0.01) G:F. Increasing soybean hulls in diets with balanced NE decreased (linear, P < 0.02) ADFI, but did not affect G:F. In experiment 3, 600 pigs (initially 6.8 ± 0.1 kg) were used in a 42-d study. Pigs were fed 1 of 10 diets containing 0%, 3%, 6%, 9%, or 12% soybean hulls without or with DDGS (15% from d 0 to 14, 30% from d 15 to 42). Feeding DDGS reduced (P < 0.04) ADG and ADFI, and tended to increase (P < 0.06) G:F. Increasing soybean hulls decreased G:F quadratically (P < 0.03) in diets without DDGS, but decreased G:F linearly (P < 0.01) in diets with DDGS (soybean hulls × DDGS interaction, P < 0.05). In experiment 4, 304 barrows (initially 11.7 ± 0.2 kg) were used in a 21-d study. Pigs were fed one of eight diets containing 0%, 5%, 10%, or 15% soybean hulls with or without 20% DDGS. No soybean hull × DDGS interactions were observed. Increasing soybean hulls tended to decrease (linear, P < 0.08) G:F. In conclusion, feeding low levels of soybean hulls did not affect nursery pig performance but more than 5% soybean hulls, with or without DDGS, decreased G:F. Formulating diets containing soybean hulls on an equal NE basis eliminated the negative effects on G:F, but the NE (1,003 kcal/kg) of soybean hulls used in this study was underestimated.

Expression of genes related to energy metabolism and the unfolded protein response in dairy cow mammary cells is affected differently during dietary supplementation with energy from protein and fat

Secretory capacity of bovine mammary glands is enabled by a high number of secretory cells and their ability to use a range of metabolites to produce milk components. We isolated RNA from milk fat to measure expression of genes involved in energy-yielding pathways and the unfolded protein response in mammary glands of lactating cows given supplemental energy from protein (PT) and fat (FT) tested in a 2 × 2 factorial arrangement. We hypothesized that PT and FT would affect expression of genes in the branched-chain AA catabolic pathway and tricarboxylic acid (TCA) cycle based on the different energy types (aminogenic versus lipogenic) used to synthesize milk components. We also hypothesized that the response of genes related to endoplasmic reticulum (ER) homeostasis via the unfolded protein response would reflect the increase in milk production stimulated by PT and FT. Fifty-six multiparous Holstein-Friesian dairy cows were fed a basal total mixed ration (34% grass silage, 33% corn silage, 5% grass hay, and 28% concentrate on a dry matter basis) for a 28-d control period. Experimental rations were then fed for 28 d, consisting of (1) low protein, low fat (LP/LF); (2) high protein, low fat (HP/LF); (3) low protein, high fat (LP/HF); or (4) high protein and high fat (HP/HF). To obtain the high-protein (HP) and high-fat (HF) diets, intake of the basal ration was restricted and supplemented isoenergetically (net energy basis) with 2.0 kg/d rumen-protected protein (soybean + rapeseed, 50:50 mixture on dry matter basis) and 0.68 kg/d hydrogenated palm fatty acids on a dry matter basis. RNA from milk fat samples collected on d 27 of each period underwent real-time quantitative PCR. Energy from protein increased expression of BCAT1 (branched-chain amino acid transferase 1) mRNA, but only at the LF level, and tended to decrease expression of mRNA encoding the main subunit of the branched-chain keto-acid dehydrogenase complex. mRNA expression of malic enzyme, a proposed channeling route for AA though the TCA cycle, was decreased by PT, but only at the LF level. Expression of genes associated with de novo fatty acid synthesis was not affected by PT or FT. Energy from fat had no independent effect on genes related to ER homeostasis. At the LF level, PT activated XBP1 (X-box binding protein 1) mRNA. At the HF level, PT increased mRNA expression of the gene encoding GADD34 (growth arrest and DNA damage-inducible 34). These findings support our hypothesis that mammary cells use aminogenic and lipogenic precursors differently for milk component production when dietary intervention alters AA and fatty acid supply. They also suggest that mammary cells respond to increased AA supply through mechanisms of ER homeostasis, dependent on the presence of FT.

Feed and nitrogen efficiency are affected differently but milk lactose production is stimulated equally when isoenergetic protein and fat is supplemented in lactating dairy cow diets

Fifty-six Holstein-Friesian cows were used in a randomized complete block design to test the effects of supplemental energy from protein (PT) and fat (FT) on lactation performance and nutrient digestibility in a 2 × 2 factorial arrangement. During the control period, cows were adapted for 28 d to a basal total mixed ration consisting of 34% grass silage, 33% corn silage, 5% grass hay, and 28% concentrate on a dry matter (DM) basis. Experimental rations were fed for 28 d immediately following the control period and consisted of (1) low protein, low fat (LP/LF), (2) high protein, low fat (HP/LF), (3) low protein, high fat (LP/HF), or (4) high protein and high fat (HP/HF). To obtain the HP and HF diets, intake of the basal ration was restricted and supplemented isoenergetically (net energy basis) with 2.0 kg/d of rumen-protected protein (soybean + rapeseed, 50:50 mixture on DM basis) and 0.68 kg/d of hydrogenated palm fatty acids (FA) on a DM basis. Milk production and composition, nutrient intake, and apparent digestibility were measured during the final 7 d of the control and experimental periods. No interaction was found between PT and FT on milk production and composition. Yields of milk, fat- and protein-corrected milk, and lactose increased in response to PT and FT and lactose concentration was unaffected by treatment. Milk protein concentration and yield increased in response to PT, and protein yield tended to increase in response to FT. Milk fat concentration and yield increased in response to FT and were unaffected by PT. Milk urea concentration increased and nitrogen efficiency decreased in response to PT. Feed and nitrogen efficiency were highest on the LP/HF diet and both parameters increased in response to FT, whereas milk urea concentration was not affected by FT. Energy from fat increased the concentration and yield of ≥16-carbon FA in milk and decreased the concentration of FA synthesized de novo, but had no effect on their yield. Concentration and yield of de novo-synthesized FA increased in response to PT. Concentration and yield of polyunsaturated FA increased and decreased in response to PT and FT, respectively. Apparent total-tract digestibility of crude fat decreased in response to PT, and FT increased crude protein digestibility. Energy supplementation through rumen-inert hydrogenated palm FA appears to be an efficient feeding strategy to stimulate milk production with regard to feed and nitrogen efficiency compared with supplementing an isoenergetic level of rumen-protected protein.

Net energy system of feed formulation with or without enzyme supplementation in growing-finishing pigs fed barley-based diets with alternative feed ingredients

The aim of this study was to determine the growth performance and carcass characteristics of growing-finishing pigs fed diets formulated on net energy (NE) basis with or without exogenous enzyme supplementation. Twenty-four pigs with an initial body weight (BW) of 25 kg were randomly allotted one of three treatments; a barley-based control diet formulated on a digestible energy (DE) basis (Diet A), control diet formulated on an NE basis (Diet B), and Diet B + multicarbohydrase enzyme (Diet C). Pigs were offered their respective diets in a 3-phase feeding program. Individual pig BW and feed disappearance were monitored once every 2 wk. Pigs were slaughtered when they reached 100 kg BW to determine carcass characteristics. During phase 1, an improvement (P = 0.02) in feed intake was observed in pigs fed Diet C compared with Diet B. In phase 3, pigs fed Diet B showed improvement in daily gain (P = 0.02) and feed efficiency (P = 0.05) compared with Diet A. Overall, when compared with control diet, pigs fed Diet B showed significant improvement in daily gain (P = 0.05) and feed efficiency (P = 0.01). In conclusion, the results indicate a better growth performance with diets formulated using the NE system. Moreover, enzyme supplementation had no effect on the overall performance of pigs.

Formulating diets containing corn distillers dried grains with solubles on a net energy basis: Effects on pig performance and on energy and nutrient digestibility

ABSTRACT A field-scale study was conducted to determine whether formulating diets containing corn, soybean meal, soybean oil, and corn dried distillers grains with solubles (C-DDGS) on an equal NE basis would affect pig performance. Two additional experiments were conducted to determine the DE and ME of these same diets (Exp. 2) and the same C-DDGS sample (Exp. 3) used in Exp. 1 to generate data to support results obtained from the field trial. In Exp. 1, 3 barns, each containing 48 pens and 20 pigs per pen (2,880 pigs) were used. Diets were formulated to contain 0, 10, 20, and 30% C-DDGS, with calculated dietary NE and standardized ileal-digestible Lys being equal across all C-DDGS levels. The NE values (kcal/kg as is) used in feed formulation were corn, 2,557; soybean meal, 1,960; soybean oil, 7,544; and C-DDGS, 2,284. Diets were additionally formulated to meet or exceed the amino acid and mineral needs according to the NRC (2012) recommendations. There were no differences ( P ≥ 0.10) noted for pig ADG, ADFI, or G:F among pigs fed the different C-DDGS levels when evaluated on d 28 (36 replications per treatment) or on d 39 (24 replications per treatment due to scale calibration error in one barn). In addition, there was no effect of dietary treatment on DP ( P ≥ 0.10), suggesting that the estimates of NE used for feed formulation were relatively accurate. When the complete diets were fed to pigs in metabolism crates (Exp. 2), apparent total-tract digestibility of DM, ether extract, NDF, and phosphorus, and dietary DE and ME, increased with increasing C-DDGS levels ( P ≤ 0.05). In Exp. 3, the ME in the C-DDGS used in Exp. 1 and 2 was determined to be 3,682 kcal/kg of DM, which was similar to the formulated value of 3,702 kcal of ME/kg of DM. Overall, the data suggest that the NE levels used for corn, soybean meal, soybean oil, and C-DDGS were relatively accurate given that pig performance and DP were unaffected by C-DDGS inclusion level. Differences in apparent total-tract digestibility of dietary DM, ether extract, NDF, and phosphorus could be directly related to digestibility differences in these nutrients, C-DDGS compared with corn, soybean meal, and soybean oil. These results support the formulating of diets on a NE basis, which is especially important in using alternative feedstuffs in swine feed formulation.

Effects of crystalline amino acid supplementation of reduced crude protein (RCP) diet on net energy basis on Longissimus muscle (LM) quality of growing-finishing swine

Effects of crystalline amino acid supplementation of reduced crude protein (RCP) diet on net energy basis on Longissimus muscle (LM) quality of growing-finishing swine

The effect of marine algae in the ration of high-yielding dairy cows during transition on metabolic parameters in serum and follicular fluid around parturition

Sixteen Holstein cows were assigned to 2 groups to evaluate the caloric and metabolic effect of feeding marine algae (ALG) from 3 wk prepartum until 12 wk postpartum. Milk production characteristics and the profiles of hormones and metabolites in the serum were monitored from −7 to 46 d in milk (DIM) and in follicular fluid (FF) from 14 to 46 DIM. All cows received a corn- and grass silage-based partially mixed ration supplemented with concentrate and protein supplement. In the diet of the ALG group, 2kg of the concentrate was replaced by a concentrate containing ALG (44g/d of docosahexaenoic acid). Diets were isocaloric (net energy basis) and equal in intestinal digestible protein. The ALG diet increased milk yield (41.2 vs. 38.2kg/d) and decreased milk fat yield (1.181 vs. 1.493kg/d) and milk fat content (31.6 vs. 40.7g/kg). Protein yield (1.336 vs. 1.301kg/d) was not affected but a tendency toward decreased milk protein content (32.8 vs. 34.7g/kg) was observed. Marine algae supplementation increased the β-hydroxybutyric acid (BHBA) concentration in FF of the ALG cows compared with that in the controls (0.992 vs. 0.718mmol/L). The total protein concentration in FF was decreased in ALG (62.9 vs. 67.6g/L). Plasma and serum metabolites did not significantly differ between treatments except for a tendency toward a lower concentration of urea in the serum of the control compared with ALG (4.69 vs. 5.13mmol/L). Based on metabolizable energy calculations, a daily energy-sparing effect of 3.48 Mcal was obtained due to milk fat depression (MFD). The concomitant increase in milk yield suggests that at least part of this spared energy is used to stimulate milk production. Theoretically, 3.48 Mcal of ME could lead to an increase in milk yield of 7.43kg/d, which is higher than the observed 3kg/d. However, when evaluating nutrient requirements during MFD in early lactation, we calculated that increased milk production is caused by a propionate-saving effect of 2.71mol in the udder when milk fat is depressed. Concurrent increased BHBA concentrations in FF in the ALG group cannot be attributed to a worsened energy status of the animals because all other indicators contradict any change in energy balance, indicating that BHBA might not be an appropriate metabolic parameter to estimate the energy balance in early lactating dairy cows during MFD.

The response of growth performance, nitrogen, and phosphorus excretion of growing–finishing pigs to diets containing incremental levels of maize dried distiller's grains with solubles

A completely randomized design experiment was performed to examine the effect of formulating incremental concentrations of dietary maize dried distiller's grains with solubles (DDGS) on a net energy (NE) and ileal digestible amino acid (IDAA) basis, on growth performance and coefficient of total tract apparent digestibility (CTTAD) parameters of growing–finishing pigs. The study investigated the effect of incrementally replacing diet wheat with DDGS on pig growth performance, carcass characteristics, apparent nutrient digestibility, nitrogen (N) balance, phosphorus (P) balance and manure ammonia emissions. Three hundred and fifty-two pigs (42.4 kg, SD = 6.4 kg) were blocked on the basis of initial body-weight (BW) and assigned to one of four dietary treatments: (T1) basal diet, (T2) basal diet with 100 g/kg DDGS, (T3) basal diet with 200 g/kg DDGS and (T4) basal diet with 300 g/kg of DDGS. The inclusion of DDGS in the diet was achieved by decreasing concentrations of wheat and all dietary treatments were formulated to contain similar concentrations of IDAA, available P and NE. There was no effect of increasing levels of DDGS on daily gain, feed intake, feed conversion ratio (FCR) and carcass characteristics during the experimental period (P>0.05). There was a linear decrease (P<0.01) in the CTTAD of dry matter and gross energy with increasing levels of DDGS in the diet. There was a linear increase in N intake (P<0.001), urinary N excretion (P<0.01) and total N excretion (P<0.01) with increasing levels of DDGS in the diet. There was a linear decrease (P<0.01) in P intake as the level of DDGS increased in the diet. There was no difference in manure ammonia emissions as the level of DDGS increased in the diet (P>0.05). In conclusion, when formulated on a NE and IDAA basis, consumption of DDGS at inclusion rates of up to 300 g/kg does not affect growth performance or carcass characteristics. While incremental consumption of dietary DDGS increased total N excretion, this was not reflected in elevated manure ammonia emissions.

Influence of incrementally substituting dietary soya bean meal for rapeseed meal on nutrient digestibility, nitrogen excretion, growth performance and ammonia emissions from growing-finishing pigs

A completely randomised design experiment was performed to examine the effects of replacing different levels of soya bean meal (SBM) with rapeseed meal (RSM) on the growth performance, carcass characteristics, apparent nutrient digestibility, nitrogen (N) balance and manure ammonia emissions of growing-finishing pigs. Pigs (n = 336; mean live weight 42.1 kg) were assigned to one of four dietary treatments containing per kg diet: 210 g SBM; 140 g SBM and 70 g RSM; 70 g SBM and 140 g RSM; and 210 g RSM. All diets were formulated on an ileal digestible amino acid, net energy and available phosphorus basis. There was no significant treatment effect on average daily gain, feed intake, feed conversion ratio and carcass characteristics. There was a linear decrease in gross energy digestibility (p < 0.01) as RSM increased at the expense of SBM in the diet. There was a linear decrease in urinary N excretion (p < 0.01), N digestibility (p < 0.05), total N excretion (p < 0.05) and N retention (p < 0.05) with increasing levels of RSM. There was no effect of dietary treatment on manure ammonia emissions. The results of this study indicate that RSM can be used as a direct replacement for SBM with no associated depression in performance, when formulated on an ileal digestible amino acid and net energy basis. Consumption of diets containing incremental levels of RSM linearly decreased urinary N and total N excretion, reflecting the associated decrease in crude protein concentrations.

Natural Antibodies Related to Energy Balance in Early Lactation Dairy Cows

The objectives of this study were to determine the presence of natural antibodies (NAb) in plasma and milk of individual dairy cows and to study the relation between NAb concentrations and energy balance (EB) and dietary energy source. Cows (n=76) were fed a mainly glucogenic, lipogenic, or a mixture of both diets (50:50 dry matter basis) from wk 3 before the expected calving date until wk 9 postpartum. Diets were isocaloric (net energy basis) and equal in intestinal digestible protein. Blood and milk were sampled weekly. Liver biopsies were taken in wk −2, 2, 4, and 6 relative to calving. Data are expressed as LSM±SEM. The NAb titers are expressed as the 2log values of the highest dilution giving a positive reaction. The NAb concentration in plasma binding either keyhole limpet hemocyanin (KLH) or Escherichia coli lipopolysaccharide (LPS) increased with parity. The NAb concentration binding KLH was greater for cows fed the glucogenic diet (9.63±0.08) compared with the lipogenic diet (9.26±0.08). In milk, cows fed the glucogenic diet had smaller NAb concentrations binding KLH (3.98±0.18) and LPS (2.88±0.17) compared with cows fed the mixed diet (KLH: 4.93±0.18; LPS: 3.70±0.17). The NAb concentration in plasma had a positive relation with energy balance variables: EB, dry matter intake, milk yield, and plasma cholesterol, whereas NAb concentration in milk had a negative relation with energy balance variables: EB, dry matter intake, and plasma cholesterol. Additionally, NAb concentrations in milk had a positive relation with plasma nonesterified fatty acid concentration and milk fat and protein percentage. There was a tendency for a positive relation of NAb concentration binding LPS in plasma and somatic cell count in milk. No significant relations were detected between NAb concentrations in milk or plasma and plasma β-hydroxybutyrate concentration and liver triacyl glyceride content. In conclusion, NAb are present in both milk and plasma of dairy cows peripartum and NAb concentrations increase with parity. Furthermore, our data indicate that a negative energy balance in dairy cows in early lactation can be associated with compromised innate immune function as indicated by decreased NAb concentration in plasma.

Effect of Glucogenic vs. Lipogenic Diets on Energy Balance, Blood Metabolites, and Reproduction in Primiparous and Multiparous Dairy Cows in Early Lactation

Increasing the availability of glucogenic nutrients relative to lipogenic nutrients has been hypothesized to decrease the production of milk fat, to improve the energy balance (EB), and to decrease the incidence and severity of metabolic and reproductive disorders in dairy cows in early lactation. Therefore, our objective was to evaluate the effects of a glucogenic, lipogenic, or mixed diet on EB, plasma metabolites and metabolic hormones, liver triacylglycerides (TAG), and reproductive variables in high-producing dairy cows in early lactation. Cows (n=114) were randomly assigned to 1 of 3 diets and were fed either a mainly lipogenic diet, a mainly glucogenic diet, or a mixture of both diets (50:50 dry matter basis) from wk 3 before the expected calving date until 9 wk postpartum. Diets were isocaloric (net energy basis) and equal in intestinal digestible protein. Dry matter intake, net energy intake, milk yield, and milk protein percentage did not differ among diets. Milk lactose percentage was less for cows fed the lipogenic diet. Milk fat percentage was less for multiparous cows fed the glucogenic diet compared with cows fed the mixed or lipogenic diet (3.69 vs. 4.02 vs. 4.22±0.07%, respectively). The calculated EB was less negative for multiparous cows fed the glucogenic diet compared with cows fed the mixed or lipogenic diet [−33 vs. −125 vs. −89±21 kJ/(kg0.75 · d), respectively]. Postpartum, the glucogenic diet decreased plasma nonesterified fatty acids, β-hydroxybutyrate, and liver TAG concentrations and increased insulin concentration in multiparous cows. The glucogenic diet tended to decrease the number of days until first milk progesterone rise in multiparous cows compared with the mixed or lipogenic diet (20.4 vs. 24.4 vs. 26.4±2.1 d, respectively). Diet had no effect on any of the above-mentioned variables in primiparous cows, except that milk lactose percentage was greater for primiparous cows fed the glucogenic diet. We concluded that the glucogenic diet was effective in improving the calculated EB and decreasing plasma β-hydroxybutyrate and liver TAG concentrations, suggesting a reduced risk of metabolic disorders in multiparous dairy cows fed a glucogenic diet.

Dietary Energy Source in Dairy Cows in Early Lactation: Metabolites and Metabolic Hormones

Negative energy balance-related metabolic disorders suggest that the balance between available lipogenic and glucogenic nutrients is important. The objectives of this study were to compare the effects of a glucogenic or a lipogenic diet on liver triacylglycerides (TAG), metabolites, and metabolic hormones in dairy cows in early lactation and to relate metabolite concentrations to the determined energy retention in body mass (ER). Sixteen dairy cows were fed either a lipogenic or glucogenic diet from wk 3 prepartum to wk 9 postpartum (pp) and were housed in climate respiration chambers from wk 2 to 9 pp. Diets were isocaloric (net energy basis). Postpartum, cows fed a lipogenic diet tended to have higher nonesterified fatty acid concentration (NEFA; 0.46±0.04 vs. 0.37±0.04 mmol/L) and lower insulin concentration (4.0±0.5 vs. 5.5±0.6μIU/mL). No difference was found in plasma glucose, β-hydroxybutyrate, insulin-like growth factor-I, and thyroid hormones. Liver TAG was equal between both diets in wk −2 and 2 pp. In wk 4 pp cows fed the glucogenic diet had numerically lower TAG levels, although there was no significant dietary effect. Negative relationships were detected between ER and milk fat and between ER and NEFA. A positive relationship was detected between ER and insulin concentration. Overall, results suggest that insulin plays a regulating role in altering energy partitioning between milk and body tissue. Feeding lactating dairy cows a glucogenic diet decreased mobilization of body fat compared with a lipogenic diet. The relative abundance of lipogenic nutrients, when feeding a more lipogenic diet, is related to more secretion of lipogenic nutrients in milk, lower plasma insulin, and higher plasma NEFA concentration.

Dietary Energy Source in Dairy Cows in Early Lactation: Energy Partitioning and Milk Composition

Metabolic problems related to negative energy balance suggest a role for the balance in supply of lipogenic and glucogenic nutrients. To test the effect of lipogenic and glucogenic nutrients on energy partitioning, energy balance and nitrogen balance of 16 lactating dairy cows were determined by indirect calorimetry in climate respiration chambers from wk 2 to 9 postpartum. Cows were fed a diet high in lipogenic nutrients or a diet high in glucogenic nutrients from wk 3 prepartum until wk 9 postpartum. Diets were isocaloric (net energy basis) and equal in intestinal digestible protein. There was no effect of diet on metabolizable energy intake and heat production. Cows fed the lipogenic diet partitioned more energy to milk than cows fed the glucogenic diet [1,175±18 vs. 1,073±12 kJ/(kg0.75·d)] and had a higher milk fat yield (1.89±0.02 vs. 1.67±0.03 kg/d). The increase in milk fat production was caused by an increase in C16:0, C18:0, and C18:1 in milk fat. No difference was found in energy retained as body protein, but energy mobilized from body fat tended to be higher in cows fed the lipogenic diet than in cows fed the glucogenic diet [190±23 vs. 113±26 kJ/(kg0.75·d)]. Overall, results demonstrate that energy partitioning between milk and body tissue can be altered by feeding isocaloric diets differing in lipogenic and glucogenic nutrient content.

An economic comparison of traditional and conventional agricultural systems at a county level

AbstractIn Holmes and Wayne Counties, Ohio, respectively, one-half and one-fourth of the farms belong to the Amish, an agrarian culture whose traditional agriculture has been remarkably successful. In an analysis of the 88 Ohio counties by means of the federal agricultural census, the economic performance of the two counties was examined in graphs of agricultural characteristics and financial indicators, some expressed on a per-ha basis across total farmland, as a measure of the efficiency of land utilization. Their performance was assessed relative to the following three groups of Ohio counties with high per-ha net farm income: those with large mean farm size, a prevalence of nursery and greenhouse production, or mixed crop and livestock agriculture. Belonging to the latter group, Holmes County ranked tenth and thirteenth highest among Ohio counties in per-ha gross and net farm income, respectively, and Wayne County, fifth and sixth. Despite the small mean farm size of 50 and 62 ha for Holmes and Wayne Counties, respectively, they matched counties of large mean farm size in terms of perha net farm income, and among 22 counties with small mean farm size of about 60 ha or less, they were exceeded only by 3 counties based on intensive nursery and greenhouse production. The large incomes were due to high marketed value of animal products. Supplemental feed consumption was 2.0 and 1.3 times the harvested crop production in Holmes and Wayne Counties, respectively, thus indicating large net imports of purchased feed. The large net incomes for the two counties were also a result of low labor costs, partly due to the fact that the Amish do not charge for helping each other on farms. When a conventional charge was applied to Amish labor, Wayne County remained among the highest of Ohio counties in per-ha net farm income, but Holmes County dropped to near the 50th percentile. Nonetheless, for the same decline, Holmes County remained among the highest of the 22 counties of small mean farm size because its initial performance was well above most of these counties. Since this was a study of land use efficiency, some discussion is devoted to farm size and productivity, relative levels of animal production, and cropland requirements to power horses and biofueled mechanical traction, the former an integral component of Amish agriculture. In the latter topic, corn-based ethanol and horse feed would require roughly the same area of cropland for traction to farm the nation's cropland, but on a net energy basis, the former area would be more than twice the latter. Since animal production is a major component of Amish agriculture, the results of the study provide indirect evidence that the small-scale, traditional farming of the Amish contributes substantially to the agricultural economies of Holmes and Wayne Counties.

Effects of Low-Protein, Amino Acid-Fortified Diets Formulated on a Net Energy Basis on Growth Performance and Carcass Characteristics of Finishing Pigs

Smith, J.W.II, O'Quinn, P.R., Goodband, R.D., Tokach, M.D. and Nelssen, J.L. 1999. Effects of low-protein, amino acid-fortified diets formulated on a net energy basis on growth performance and carcass characteristics of finishing pigs. J. Appl. Anim. Res., 15: 1–16. Two hundred eighty-eight crossbred gilts (PIC L326 x C22, initially 48 kg) were used to determine the effects of corn-soybean meal or low protein, amino acid-fortified diets formulated to equal net energy (NE) concentrations on growth performance and carcass characteristics of growing-finishing pigs. Diets were formulated to two NE concentrations, 2.51 and 2.58 Mcal/kg during growing and 2.58 and 2.65Mcal/kg during finishing period. Amino acids were provided from soybean meal or a combination of soybean meal and crystalline amino acids (L-lysine, DL-methionine, L-threonine, and L-tryptophan) formulated on an ideal protein basis. Pigs fed diets containing intact protein had greater (P<0.01) ADG, G:F and percentage lean than pigs provided diets containing crystalline amino acids. For the overall experiment, pigs fed high NE had greater (P<0.10) ADG, ADFI, 10th rib fat depth and percentage lean than pigs fed low NE. This study showed that pigs fed low-protein, amino acid-fortified diets had lower ADG, G:F and percentage lean compared with pigs fed intact protein, regardless of NE.

Effects of low-protein, amino acid-fortified diets, formulated on a net energy basis, on the growth performance and carcass characteristics of finishing pigs (1996)

Effects of low-protein, amino acid-fortified diets, formulated on a net energy basis, on the growth performance and carcass characteristics of finishing pigs (1996)

Silage‐Concentrate Substitution; Effects on Milk Production and Income Over Feed Cost in DHIA Herds

AbstractMilk production response was determined with feed inputs and milk production converted to an estimated net energy basis. Differences in cow size, production, butterfat, and feed quality were taken into account. The data resulted in improved explanation of output variation and showed the importance of silage quality on silage‐concentrate substitution.

Influence of Sucrose on Rumen Fermentation Pattern and Milk Fat Content of Cows Fed a High-Grain Ration

Milk fat content was not increased by replacing milo with sucrose at levels representing 5,10, and 15% of the dry matter in rations containing 10% alfalfa hay and fed in excess of National Research Council requirements. The experiment involving 16 cows was conducted in randomized block design. It consisted of a standardization period of two weeks, a transition period of four weeks, and a comparison period of sixteen weeks. During the standardization period the cows received ad libitum a ration comprised of 40% alfalfa hay (estimated net energy basis) and 60% ground milo plus minerals.There were no significant differences among the covariant-adjusted treatment means for milk and solids-corrected milk production, milk fat, and solids-not-fat content, or production efficiency. In the rumen contents pH was lower (P<0.05) and lactate concentration was higher (P<0.10) with sucrose in the ration. The mean proportions of rumen volatile fatty acids were not significantly different among treatments.