Total Dry Matter Intake Research Articles

ឥទ្ធិពលនៃការប្រើប្រាស់ចំណីសម្រេច និងត្រកួនកម្រិតខុសគ្នាជាមួយកន្ទក់ លើការរំលាយអាហារ និងតុល្យភាពអាសូតរបស់ជ្រូកកូនកាត់ក្នុងស្រុក

This experimental study aims to compare feed intake, digestibility and nitrogen retention of pigs fed with four diets. Eight castrated male pigs (Yorkshire x Local breed) of average live weight of 15 kg were given four diets in a double 4*4 Latin square arrangement. The experiment included four treatments, including T1: Concentrate feed 15% + Water spinach 50% + Rice bran 35%; T2: Concentrate feed 30% + Water spinach 35% + Rice bran 35%; T3: Concentrate feed 45% + Water spinach 20% + Rice bran 35%; and T4: Concentrate feed 60% + Water spinach 5% + Rice bran 35%. The results showed that the total intakes of dry matter (DM) and crude protein (CP) in T4 were (1.044g/day) and (182.5g/day), respectively, which were significantly higher than the other three treatments (p<0.01). The digestibility of T4 was significantly higher than the other three treatments (p<0.01) as well. The nitrogen retention of T4 (10.84g/day) was also significantly higher than T1 (p<0.01). However, there was non-significant difference as compared to T2 and T3 (p>0.05). Overall, the mixture of concentrate feed 60%, water spinach 5%, and rice bran 35% made the pigs get high feed intake and high digestibility, as well as better Nitrogen absorption in their bodies.

Enhancing dairy productivity through best bet feeding interventions under smallholders in the central highlands of Ethiopia

Dairy cattle production is an integral part of smallholder farming systems in the central highlands of Ethiopia, but it is characterized by low milk productivity mainly due to nutritional constraints. This study assessed the comparative advantage of using improved forage-based feeding system over the traditional feeding practices on feed intake, milk yield and quality, and cost benefit analysis of crossbred dairy cows under smallholder farmers. The study was conducted at Welmera and Ejere districts on 12 farmers and two cows per farmer, and two dietary treatments were assigned to each cow randomly, and the study lasted 8 weeks. The treatments were: 1) intervention diet composed of oats-vetch mixture hay with concentrate supplementation at the rate of 0.5 kg/l of milk and 2) basal diet following farmers’ current feeding practices: crop residues and native hay, commonly soaked with local brewery residue (“Atela”) and water. The results showed that there was no difference in total dry matter intake between the two diets. However, the basal feed intake was higher in the traditional feeding practice by 11% whereas the concentrate intake was higher in the intervention diet by 25%. Crude protein intake was significantly higher (P<0.05) in the intervention group by 23%. As a result, milk yield was increased by 36% under oat-vetch mixed fodder-based feeding system as compared to the traditional feeding practice. Consequently, the amount of feed required per unit of milk was lower in the intervention group, indicating higher feed conversion efficiency as compared to the traditional feeding practice. On the other hand, there was no significant variation in milk composition between the two groups. Partial budget analysis indicated that the benefit from the intervention diet (95 birr/cow/day) was greater by 266% than that obtained from the traditional practice (45 birr/cow/day). Utilization of improved forage varieties was proven to play significant role in supplying good quality and abundant feed resource that increased milk yield and also fetch additional economic return for smallholder farmers compared to the existing traditional practice. In general, this study demonstrates that adoption of improved forage production and feeding practices along with sufficient training on balanced ration formulation has been observed to increase dairy productivity and food security through provision of sustainable livelihood opportunity for smallholder farmers.

Nitrogen and energy losses and methane emissions from beef cattle fed diets with gradual replacement of maize silage and concentrate with grass silage and corn-cob mix.

Diets based on large proportions of grassland-based feed are uncommon in forage-based intensive beef production, thus contradicting governmental or commercial strategies to promote the use of grassland-based feed in ruminant production systems. Compared with typical maize silage/concentrate diets, grassland-based diets are associated with impaired nitrogen (N) and energy utilisation because of the comparably lower energy and higher CP content of these feeds. However, quantitative studies concerning the effects of increased dietary proportions of grassland-derived feeds on N and energy losses and utilisation and on methane emissions are missing and the compensation potential of using a limited proportion of an energy-rich forage is unknown. Therefore, we tested five diets with varying types and proportions of forage and concentrate. Three diets consisted of grass silage, maize silage, and concentrate in ratios of, g/kg DM, 100:600:300 (G100; control), 300:500:200 (G300), and 500:300:200 (G500), respectively. Two diets were composed of grass silage, corn-cob mix (CCM), and concentrate in ratios of, g/kg DM, 500:300:200 (G500CCM), and 750:150:100 (G750CCM), respectively. A high-protein concentrate (270g CP/kg DM) was fed to G100, whereas a low-protein concentrate (140g CP/kg DM) was used in the remaining diets. Diets were fed throughout the entire fattening period to groups of six Limousin-crossbred bulls each. When weighing 246±18kg, each animal underwent a 7-day total daily faeces and urine collection, which was followed by measuring methane emissions in respiration chambers for 48h. Total DM intake was similar across all diets, whereas the N intake varied (P<0.05). Urinary N loss (g/day) was the highest for G750CCM (28.2) and G100 (26.6) and lowest for G500CCM (15.2) and G300 (16.9) (P<0.001). Energy utilisation was comparable among all groups. Metabolisable energy intake decreased numerically only with increasing proportions of grass silage in the diet. Substituting maize silage with CCM counteracted the loss in metabolisable energy intake. Absolute methane emissions were not different across the groups, but methane emission intensity (mg/g body protein retention) varied (P<0.05), being numerically lower for G100 (349) and G500CCM (401) compared with the other groups (488 on average). In conclusion, the results show that the grass silage proportion in beef cattle diets can be substantially increased when strategically combined with energy-dense forages, such as CCM. This also limits the need for concentrate and additional protein sources; in addition, the associated urinary N emissions, which are potentially noxious to the environment, are avoided.

Optimizing amla (Phyllanthus emblica) fruit powder supplementation in liquid feed fed to Holstein dairy calves: Insights from growth performance and health events

Despite efforts at improvement, calf diarrhea remains one of the main problems in calf rearing. Amla (Phyllanthus emblica) fruit could be a good candidate to improve gut health due to its antimicrobial, gastro-protective, and immunomodulatory effects. This study aimed to evaluate the effect of amla fruit powder supplementation on frequency of diarrhea and growth performance of dairy calves. One hundred male Holstein calves [2-days (d)-old; 42.6 ± 1.7 kg body weight (BW)] were randomly assigned into five treatments, CON, PEF5, PEF10, PEF20, and PEF40, with 0, 5, 10, 20, and 40 g/d amla fruit powder (PEF) supplementation, respectively, and housed in individual hutches (n = 20 calves per treatment). The experiment lasted from 2 to 75 d of age (weaning) and calves were fed milk (2–7 d), milk replacer (8–75 d), and calf starter (2–75 d). The PEF supplementations were fed in two meals a day, equal amount each time, by mixing into milk or milk replacer. Feed intake and fecal score data were collected daily; BW and body frame measurements at 2, 14, 28, 42, and 75 d; and rumen fluid samples at 14, 28, 42, and 75 d. Starter and total dry matter intakes (DMI) differed among treatments during 22–75 with the highest in CON and linearly decreased with increasing PEF doses. Liquid feed DMI tended to decrease with increasing PEF doses. PEF supplementation had quadratic effect on body weight (BW), average daily gain (ADG), feed efficiency, body length, heart girth, and withers height. The BW and ADG differed among treatments during 29–75 and 15–75 d, respectively, with the highest in PEF5 followed by CON and lowest in PEF40. However, PEF did not improve BW and ADG compared to the CON. The overall feed efficiency in PEF5 was higher than in PEF20 and PEF40. PEF5 decreased the frequency of fecal score “3” (P = 0.02) while PEF5 (P < 0.01) and PEF10 (P = 0.03) increased the frequency of fecal score “1”, compared to the CON. Frequency of diarrhea in the PEF5 group (7.9%) was lower (P < 0.05) than all groups (11.1%, 14.3%, 22.6%, and 24.2% for PEF10, PEF20, and PEF40, respectively). Rumen fermentation (pH, ammonia-N, and volatile fatty acids) was not affected by PEF supplementation. However, ammonia-N showed a decreasing trend with increasing PEF levels. The results suggested that PEF could be fed at 5 g/d to reduce diarrhea in preweaning dairy calves.

Effect of canola oil supplementation level on total tract digestion, ruminal fermentation, and methane emissions of cows grazing Urochloa sp. supplemented with a fixed amount of concentrate

Four rumen-cannulated cows (Bos taurus × Bos indicus, 657 ± 92 kg body weight, BW) in a rotational grazing (Urochloa sp.) system were assigned to different canola oil (CO) inclusion levels, 0.0, 0.40, 0.80, and 1.2 g/kg according to shrunk body weight (SBW, BW adjusted for gastrointestinal filling) in a 4 × 4 Latin Square design to evaluate CO on the CH4 emissions and dietary energy intake. CH4 emissions were estimated using an infrared analyzer methodology (Sniffer method). Grass intake and fecal production were estimated using Cr2O3 as an external marker. CO supplementation increased (linear effect, P ≤ 0.05) total dry matter and gross energy intake with a linear increase (P = 0.09) in neutral detergent fiber (NDF) intake. While digestible energy (Mcal/kg) linearly increased with increasing CO supplementation level (linear effect, P < 0.05), total tract digestion of organic matter, NDF, and CP was comparable (P > 0.05) between levels. Maximal CO supplementation (1.2 g/kg SBW) significantly decreased total ruminal protozoa population, acetate:propionate ratio, and enteric methane production (g/kg DMI) by 9, 5.3, and 17.5%, respectively. This study showed that, for cows grazing tropical forages, CO can be supplemented up to 1.2 g/kg SBW (5.8% of the total diet) without negatively affecting intake and nutrient digestion while reducing ruminal fermentation efficiency and enteric methane emission (≤ 17.5%).

Effect of Feeding Different Percentages of Acacia saligna Foliage Hay on Barki Ewes Performance

The study was conducted to evaluate the effect of replacing berseem hay (BH) with dried Acacia saligna foliage (AFH) on the performance and some blood parameters of pregnant Barki ewes. Thirty-Two aged 2-3 years old at the last third of pregnancy (eight in each group, 40.5 ± 0.96 Kg body weight) were fed 0 (Control), 25, 50 and 75% of AFH in replacement of BH. All animals fed 2% of their body weight concentrate feed mixture and ad libitum quantities of BH or AFH forages for 84 days. Average daily change in body weight of ewesduring lactation, milk yield and composition, rumen liquor parameters (pH, volatile fatty acids, ammonia-N and protozoa count), lamb’s growth performance and some serum biochemical parameters weredetermined.Economic evaluation for the tested levels of forages was also estimated. Data were statistically analyzed using SAS computer program software utilizing the general linear model (GLM) procedure. The findings revealed that while AFH had greater neutral detergent fiber (NDF), acid detergent fiber (ADF) andcrude proteins (CP) values than BH, it had lower amounts of dry matter (DM), crude fiber (CF), ether extracts (EE) and fiber fractions. Total DM intake (g/h/day or g/Kg W ) of lactating ewes did not influence significantly by AFH 0.75 replacement in the diets. The replacement of BH with AFH at the rate of 75% resulted in increasing (P&lt;0.05) individual (Acetic, butyric and propionic) and total volatile fatty acids (VFA) concentrations compared with the control treatment. The tested incorporation levels of AFH did not influence the live body weight during the lactation period. Neglecting the lamb's sex, the tested levels of AFH had noeffect onbirth weight and body weight changes from birth till weaning. Ewes fed 75% AFH recorded the highest total milk yield and daily milk yield compared to the other tested diets.Treatmentsaffects insignificantlyfat and protein yields. Moreover, no significant effect noticed among the experimental groups in serum biochemical tested parameters. Ewes fed ration containing 75% AFH recorded the best economic efficiency compared to other tested rations.

Effect of concentrates level on digestibility, ruminal fermentation, and bacterial community in growing camels

Understanding the rumen microbiota of camels under different feeding conditions is necessary to optimize rumen fermentation and productivity. This study aims to investigate the effects of different concentrate supplement levels on digestion, rumen fermentation and bacteria in growing camels. Fifteen growing camels were divided into three groups and were fed alfalfa hay in addition to one of the three concentrate supplement levels based on body weight (BW): low (0.7%), medium (1%), and high (1.3%). Increasing the concentrate supplement level in the diet increased total dry matter intake but had no effect on nutrients digestibility, except for crude protein digestibility, which was enhanced with the high concentrate level. Growing camels at low-level had considerably higher rumen pH than those fed medium or high levels. Increasing the supplement level also increased rumen propionic acid but decreased acetic acid concentration. Principal coordinate analysis showed that concentrate levels clearly separated the ruminal bacterial communities where Bacteroidetes and Firmicutes were the dominant phyla and Prevotella, Ruminococcus, Butyrivibrio, RC9_gut_group, and Fibrobacteres were the dominant bacterial genera. This study expands our knowledge regarding the rumen microbiota of growing camels under different concentrate levels and reveals that medium concentrate levels could be appropriate for growing camels.

Effects of feeding wheat straw or beet pulp in starters supplemented with either soybean oil or palm fatty acids on growth performance and urinary purine derivatives in dairy calves

The current study aimed to evaluate the effect of wheat straw (WS) as a forage fiber source vs beet pulp (BP) as a non-forage fiber source supplemented by fat sources soybean oil (SBO) vs palm fatty acid (PLF) on growth performance, protozoal population, and urinary purine derivatives (PD) in dairy calves. Fifty-two new-born Holstein female calves (3 days of age) were assigned randomly to one of four treatments: 1) starters contained WS with SBO (WS-SBO); 2) starters contained WS with PLF (WS-PLF); 3) starters contained BP with SBO (BP-SBO); and 4) starters contained BP with PLF (BP-PLF). An equal amounts of fiber (75 g/kg dry matter) and fat (25 g/kg dry matter) was offered in experimental treatments. Milk feeding schedule was constant among experimental treatments. The starter intake was higher in calves received BP with PLF diet (P = 0.02) compared to calved received SBO diet. This coincided with fiber × fat source interaction (P = 0.05) for average daily gain (ADG) and hence BW was higher in calves fed BP along with PLF (P = 0.04). The heights for withers (P = 0.04) and hips (P = 0.01) were higher at weaning when calves received BP with PLF compared to SBO diets. Moreover, the higher ruminal concentration for short-chain fatty acids (P = 0.05) and the higher digestibility for organic matter (P = 0.03) and neutral detergent fiber (P = 0.05) were achieved when calves fed BP with PLF compared to SBO diets. Supplemental SBO reduced starter intake (P = 0.04), total dry matter intake (P = 0.01) and ADG (P = 0.01) compared to PLF diet. The protozoa population was reduced (P = 0.01) when calves were supplemented with SBO compared to calves fed PLF. Furthermore, supplemental SBO reduced total PD concentrations (P = 0.02) and consequently reduced microbial protein synthesis (P = 0.02) compared to PLF diets. Feeding BP compared to WS reduced acetate to propionate ratio (P = 0.02) during the pre-weaning period. In conclusion, based on the current study conditions, feeding WS compared to BP did not produce large differences, because of the negative results produced by SBO compared to PLF on both rumen fermentation and nutrient digestibility, feeding SBO is not advisable, whereas feeding PLF in conjunction with BP appears to provide a significant boost in growth and feed consumption in young dairy calves.

A meta-analysis on the effects of probiotics on the performance of pre-weaning dairy calves

BackgroundProbiotics have been used in livestock production for many years, but information on their benefits during the early life of calves is inconsistent. This study aimed to assess the effects of probiotics on the performance of pre-weaning dairy calves and identify the factors influencing their effect sizes.ResultsForty-nine studies were selected for meta-analysis based on the inclusion and exclusion criteria. The study qualities were evaluated using a predefined risk assessment tool following GRADE guidelines. Meta-analysis results showed that probiotics increased the growth performance (body weight by 1.988 kg and average daily gain by 40.689 g/d), decreased digestibility and feed efficiency (feed conversion rate by 0.073), altered rumen parameter (decreased acetate by 2.815 mmol/L and increased butyrate by 0.788 mmol/L), altered blood parameter (decreased AST by 4.188 U/L, increased BHBA by 0.029 mmol/L and IgG by 0.698 g/L), increased faecal parameter (faecal bacteria counts by 0.680 log10 CFU/g), based on the strict criteria (PSMD < 0.05, I2 < 50%). Additionally, probiotics increased digestibility and feed efficiency (starter dry matter intake by 0.034 kg/d and total dry matter intake by 0.020 kg/d), altered blood parameter (increased IgA by 0.313 g/L, IgM by 0.262 g/L, and total antioxidant capacity by 0.441 U/mL, decreased MDA by 0.404 nmol/mL), decreased faecal parameter (faecal score by 0.052), based on the loose criteria (PSMD < 0.05, I2 > 50%).Regression and sub-group analyses showed that probiotic strains, supplementation dosage, and methods significantly affected the performance of calves. The probiotics supplied with more than 9.5 log10 CFU/d significantly increased IgA and IgM contents (PSMD < 0.05). Additionally, the compound probiotics significantly increased TDMI, IgA, and IgM (PSMD ≤ 0.001). Furthermore, probiotics supplemented in liquid (whole milk or milk replacer) significantly increased TDMI and decreased faecal score (PSMD < 0.05), while in whole milk, they significantly increased body weight, IgA, and IgM (PSMD < 0.001).ConclusionsProbiotics could improve the growth performance, feed intake and efficiency, rumen fermentation, immune and antioxidant capacity, and health of pre-weaning calves. However, the effect sizes were related to the dosage, composition, and supplementation methods of probiotics.

Bakery waste supplementation to late gestating Bos indicus-influenced beef cows successfully impacted offspring postnatal performance.

This study evaluated the growth and immune function of beef calves born to cows supplemented with bakery waste containing two concentrations of crude fat. On day 0 (~90 d before calving), 108 multiparous Brangus crossbred cows were stratified by body weight (BW; 551 ± 65 kg) and body condition score (BCS, 5.5 ± 0.9) and randomly allocated into 1 of 18 bahiagrass (Paspalum notatum) pastures (6 cows and 4.3 ha per pasture). Treatments were randomly assigned to pastures (6 pastures per treatment) and consisted of no prepartum supplementation (NOSUP) and isocaloric and isonitrogenous supplementation of low-fat (LFAT; 6.4% crude fat) or high-fat (HFAT; 10.7% crude fat) bakery waste from days 0 to 70 (1 kg DM per cow per day). Calves were weaned on day 292 (201 ± 17 d of age). Then, 15 heifers per treatment were randomly selected and assigned to drylot pens from days 300 to 345 and vaccinated against respiratory pathogens on days 300 and 315. Cow BCS near calving (day 70) was the least (P ≤ 0.05) for NOSUP cows and did not differ (P = 0.12) between LFAT and HFAT cows. Cow BCS at the start of the breeding season (day 140) was greater (P = 0.05) for HFAT vs. NOSUP cows and intermediate (P ≥ 0.35) for LFAT cows. Plasma concentrations of total polyunsaturated fatty acids in HFAT cows did not differ (P ≥ 0.76) compared with LFAT cows but were greater (P ≤ 0.05) compared to NOSUP cows on day 70. Final pregnancy percentage did not differ (P ≥ 0.26) among treatments, but a greater percentage of HFAT cows calved (P ≤ 0.05) their second offspring during the first 21 d of the calving season compared to NOSUP and LFAT cows (bred by natural service). Weaning BW was the greatest (P ≤ 0.05) for LFAT and least for NOSUP calves. Maternal treatments did not impact (P ≥ 0.11) postweaning growth and total DM intake of calves. Average plasma cortisol concentrations were greater (P = 0.03) for NOSUP vs. HFAT calves and intermediate for LFAT calves (P ≥ 0.26). Serum titers against infectious bovine rhinotracheitis and bovine respiratory syncytial virus were greater or tended to be greater (P ≤ 0.08) for HFAT vs. LFAT calves and intermediate (P ≥ 0.27) for NOSUP calves at the end of preconditioning. Thus, supplemental fat concentration fed to late-gestating beef cows had variable effects on calf performance. Low-fat bakery waste led to the greatest calf preweaning growth, whereas high-fat bakery waste enhanced maternal reproduction and had minor benefits to calf humoral immune function.

Supplementary effects of Noug Seed (Guizotia abyssinica) Cake with Sesbania (Sesbania sesban) Leaves on Feed Intake, Digestibility and Enteric Methane Emission in Arsi-Bale Sheep

An experiment was conducted to study the effects of feeding the mixture S. sesban (Sesbania sesban) leaves, noug seed cake, and hay on feed intake, digestibility, and estimating enteric methane emission of Arsi-Bale sheep. The experiment was done having the nine-adult sheep of initial body weight 26.7 (±0. 14) kg. The experiment consisted of 7 days of digestibility and 90 days of feeding trials. The experiment employed a 3 x 3 cross over design with three treatments and three periods. There were three treatments including S. sesban leaves alone (T1), 27.6% S. sesban leaves + 27.6% hay +44.8% Noug seed cake (NSC) (T2) and 38.6% + 61.4% NSC (T3). Total dry matter intake (DMI) was higher (P&lt;0.001) for sheep feed in 27.6% + 27.6% hay + 44.8% NSC (706.9g/day) compared to the rest of the treatments. However, the effect of S. sesban leaves alone decrease the total DMI. Digestibility of DM, OM, CP (P&lt;0.01), NDF, and ADF were higher (P&lt;0.05) between the treatments. Average daily gain (ADG) was higher (P&lt;0.01) for sheep in feed 27.6% S.sesban leaves + 27.6% hay + 44.8% than those in feed S. sesban leaves alone. Increased level of S. sesban leaves supplement, in general, reduced growth in this study. However, there was no difference between 27.6% S.sesban leaves + 27.6% hay + 44.8% and 38.6% hay + 61.4% NSC. Estimation of enteric methane emissions factor and daily methane production was higher (P&lt;0.01) in treatments T2 as compared to T3 and T1. And also, T3 higher than T1. Thus, it can be concluded that S. sesban leaves can be promoted as valuable feed resources for ruminants while concurrently reducing methane emissions.

PUFA supplements to improve diarrhea, fecal consistency, and disease resilience in neonatal and preweaning calves

The flaxseed oil (FSO) rich in polyunsaturated fatty acids (PUFA) were supplemented orally to ten male and female neonatal calves from day 6 of birth to day 28 to improve resilience to disease incidences (TG) and compared to calves reared without PUFA supplement (CG). The PUFA supplementation in liquid form was discontinued on day 29 and fed as bolus consisting of 25 g of ground flaxseed and 25 g of jaggery until day 90. The total dry matter intake in cluding milk solids in neonata calves was 400 g in CG and 428 g in TG (P=0.38). Digestible DMI, CP and energy intake in male and female calves of TGs was significantly (P&lt; 0.05) higher the CG. However, the body weight gain in calves during neonatal (P=0.08) and preweaning (P=0.14) age was comparable between groups. The serum IgG were 30 mg/mL on day 2 but higher in calves in TGs on day 7 (P=0.08) and day 14 (P=0.07)after birth but comparable in subsequent period until day 30 after birth. Calves resilience to diarrhea, pyrexia, anorexia, skin infection, profused lacrimation, navel ill, muzzle keratinization, umbilical hernia, fecal consistency (FC), and egg count (FEC) were examined. PUFA supplementation reduced the disease risk rate in TG by 42% (P&lt; 0.001) and diarrhea by three folds compared to CG. Haemoglobin, erythrocytes, and lymphocytes improved significantly from day 30 after birth. The intervention was recommended to reduce calf mortality and imrpoved health and body weight gain during neonatal and preweaning age.

Feeding behaviour of beef cattle in intensive finishing on pasture and supplemented with different additives

Context Concentrate supplementation at high rates represents a method used to improve the productive efficiency of the beef cattle grazing system. Further, the use of additives increases the nutrient-use efficiency of diets. In this sense, it is important to determine the impact of additives in grazing beef cattle fed with high-concentrate supplements to determine the appropriate management practices of the system. Aim This study aimed to evaluate the feeding behaviour of Nellore beef cattle (Bos taurus indicus) in intensive finishing on pasture and fed with different additives. Methods Twenty-eight Nellore cattle [with initial bodyweight (BW) of 480 ± 5 kg and age of 24 ± 2 months] were finished on Urochloa brizantha cv. BRS Piatã pastures. The animals were assigned to a completely randomised design with four experimental supplements: U (urea as non-protein nitrogen source), UO (slow-release urea partially replacing urea), UOL (supplement UO + Saccharomyces cerevisiae yeast), and UOLP (supplement UOL + multi-strain probiotics). Key results Supplement intake and idleness time were most affected by the season (P &lt; 0.001). The total dry-matter intake was higher in UOLP (P &lt; 0.004), and this supplement also produced the least effects on feeding behaviour. Conclusion The beginning of the rains affected the feeding behaviour. The additive combination in intensive finishing on pasture, such as UOL and UOLP, improved the intake and did not affect the feeding behaviour during the day. Implications These results indicate that the use of additives in intensive finishing on pasture improves productive efficiency and does not change the animal’s behaviour, resulting in an important technology to be disseminated and applied by grazing beef cattle producers.

Performance of Dairy Cows Supplemented with By-Pass Fat under Heat Stress Conditions

The objective of this study was to determine the effect of supplementation with a protected fat source on the productive response, metabolic environment and physiological indicators in Holstein cows under heat stress conditions during a 12-week experimental period. Thirty Holstein cows were distributed in 15 blocks by parity (2.0 ± 1.1), days in milk (182 ± 80) and milk production (29.4 ± 5.7 kg·day-1) at the beginning of the trial and randomly assigned within each block to the following treatments (diets): SPF: supplementation with protected fat or WPF: without supplementation with protected fat. All the cows were kept in a dry-lot where they were given a partial mixed ration (PMR) ad libitum while in the milking parlor they received individual supplementation depending on the treatment. The SPF diet contained 4.0 kg·day-1 concentrate in pellet form + 0.6 kg·day-1 ground corn grain + 0.7 kg·day-1 protected fat, while the WPF diet was similar to that offered in SPF, but the protected fat was isoenergetically replaced by ground corn grain. The fat supplement contained fats of animal and vegetable origin and microencapsulation was used for its preparation. Total dry matter and metabolic energy intakes were similar (p > 0.05) between treatments. Fat corrected milk (4% FCM) production was higher (p = 0.04), while energy corrected milk and fat productions tended (p = 0.06) to be higher in cows from the SPF group, without effects (p > 0.05) on the rest of the milk production and composition parameters. These results could be attributed to an improvement in the efficiency of the use of the energy consumed. Protected fat supplementation neither modified the metabolic profile, nor reduced the respiratory rate and body temperature of heat-stressed cows. Future research is needed to explain this latter result.

An evaluation of detailed animal characteristics influencing the lactation production efficiency of spring-calving, pasture-based dairy cattle

Selection for feed efficiency, the ratio of output (e.g., milk yield) to feed intake, has traditionally been limited on commercial dairy farms by the necessity for detailed individual animal intake and performance data within large animal populations. The objective of the experiment was to evaluate the effects of individual animal characteristics (animal breed, genetic potential, milk production, body weight (BW), daily total dry matter intake (TDMI), and energy balance) on a cost-effective production efficiency parameter calculated as the annual fat and protein (milk solids) production per unit of mid-lactation BW (MSperBWlact). A total of 1,788 individual animal intake records measured at various stages of lactation (early, mid, and late lactation) from 207 Holstein-Friesian and 200 Jersey × Holstein-Friesian cows were used. The derived efficiency traits included daily kilograms of milk solids produced per 100 kg of BW (dMSperBWint) and daily kilograms of milk solids produced per kilogram of TDMI (dMSperTDMI). The TDMI per 100 kg of BW was also calculated (TDMI/BWint) at each stage of lactation. Animals were subsequently either ranked as the top 25% (Heff) or bottom 25% (Leff) based on their lactation production efficiency (MSperBWlact). Dairy cow breed significantly affected animal characteristics over the entire lactation and during specific periods of intake measurements. Jersey crossbred animals produced more milk, based on a lower TDMI, and achieved an increased intake per kilogram of BW. Similarly, Heff produced more milk over longer lactations, weighed less, were older, and achieved a higher TDMI compared with the Leff animals. Both Jersey × Holstein-Friesian and Heff cows achieved superior production efficiency due to lower maintenance energy requirements, and consequentially increased milk solids production per kilogram of BW and per kilogram of TDMI at all stages of lactation. Indeed, within breed, Heff animals weighed 20 kg less and produced 15% more milk solids over the total lactation than Leff. In addition, Heff achieved increased daily milk solids yield (+0.16 kg) and milk solids yield per kilogram of TDMI (+ 0.23 kg/kg DM) during intake measurement periods. Moreover, the strong and consistently positive correlations between MSperBWlact and detailed production efficiency traits (dMSperBWint, dMSperTDMI) reported here demonstrate that MSperBWlact is a robust measure that can be applied within commercial grazing dairy systems to increase the selection intensity for highly efficient animals.

Effects of substituting agro-industrial by-products for soybean meal on beef cattle feed utilization and rumen fermentation

The purpose of the present investigation was to detect the effect of replacement of soybean meal (SBM) with citric waste fermented yeast waste (CWYW) as an alternative protein source of portentous substances in a concentrate mixture diet of beef cattle on intake, digestibility, ruminal fermentation, plasma urea-nitrogen, energy partitioning, and nitrogen balance. Four Thai-native beef bulls (170 ± 10.0 kg of initial body weight) were randomly allocated to a 4 × 4 Latin square design. The dietary treatments were four levels of CWYW replacing SBM in a concentrated diet at ratios of 0, 33, 67, and 100%. SBM was added to the concentrate diet at a dose of 150 g/kg DM. All cattle were offered ad libitum rice straw and the concentrate diet at 5 g/kg of body weight. The study was composed of four periods, each lasting for 21 days. The findings demonstrated that there was no difference in total dry matter intake, nutritional intake, or digestibility between treatments (p > 0.05). When CWYW replaced SBM at 100% after 4 h of feeding, ruminal pH, ammonia nitrogen, plasma urea nitrogen, and bacterial population were highest (p < 0.05). Volatile fatty acids and energy partitioning were not different (p > 0.05) among dietary treatments. Urinary nitrogen excretion was greatest (p < 0.05) for cattle fed CWYW to replace SBM at 100% of the concentrate. However, nitrogen absorption and retention for Thai-native cattle were similar (p > 0.05) among treatments. In conclusion, CWYW may be utilized as a substitute for SBM as a source of protein in Thai-native beef cattle without having an adverse impact on feed utilization, rumen fermentation characteristics, or blood metabolites.

Effects of Castration Age on the Growth Performance of Nubian Crossbred Male Goats.

To determine the optimal timing for performing castration on goats, eighteen male Nubian crossbred goats were randomly assigned to two groups and castrated at 3 months and 6 months of age, respectively. Daily dry matter intake, biweekly body weights, and ultrasonic measurements of longissimus dorsi muscle growth were recorded. Results indicated that there was no significant difference between the two groups in terms of the blood parameter analysis (except testosterone, 0.36 ± 0.26 vs. 3.61 ± 0.27 ng/mL at 25 weeks old), economic analysis, and growth performance, including final body weight, total weight gain, average daily gain, total dry-matter intake, and feed conversion ratio (p &gt; 0.05). However, the longissimus dorsi muscle depth of goats castrated at 6 months of age was significantly higher than that of goats castrated at 3 months of age. In conclusion, castration timing does not have a significant effect on the growth performance of goats; therefore, castrating goats at 3 months of age may be the best practice considering animal welfare and possible risks associated with late castration.

Effects of corn silage supplementation strategy and grazing intensity on herbage intake, milk production, and behavior of dairy cows

Effects of corn silage supplementation on milk production of grazing dairy cows depend in part on the substitution rate between the 2 forages, which may be influenced by grazing management. The aim of this study was to compare 2 grazing management strategies for measuring substitution rate between herbage and corn silage, in interaction with grazing intensity. Six treatments were compared, with 2 grazing intensities and 3 supplementation strategies investigated at both grazing intensities. The 2 grazing intensities were severe and light grazing, defined by either (1) herbage allowance (HA) of 15 (severe) or 30 (light) kg dry matter (DM)/cow per d at 3 cm above ground level or (2) postgrazing sward height, depending on the supplementation strategy. The 3 supplementation strategies were as follows: (U) an unsupplemented treatment, (A) 5 kg DM/d of corn silage offered at a similar HA as in U, and (H) 5 kg DM/d of corn silage offered at a similar postgrazing sward height as in U. Thirty-six multiparous Holstein cows were used in a randomized complete block design and divided in 2 groups for the entire experiment, one for each grazing intensity. Within each grazing intensity group, the corn silage supplementation strategy was studied using a 3 × 3 Greco-Latin square design, with 3 periods of 14 d. Supplementing cows with corn silage increased total DM intake only for severe grazing by 1.7 kg DM/d. The substitution rate between corn silage and grazed herbage was lower for severe than for light grazing, averaging 0.63 and 1.23, respectively. Herbage dry matter intake was lower by 1.2 kg/d for strategy H than A, leading to lower substitution rates (0.81 vs. 0.99, respectively), irrespective of grazing intensity. Milk production increased with silage supplementation for severe grazing (+1.0 kg/d milk) and was unaffected by silage supplementation for light grazing (-0.4 kg/d milk). The milk production response to corn silage supplementation averaged +0.23 and -0.08 kg of milk per kg DM of silage for severe and light grazing, respectively. Fat-corrected milk production tended to be lower by 0.4 kg/d for strategy H than A, leading to lower milk production response (+0.00 vs. +0.12 kg of milk per kg DM of silage, respectively). Milk protein concentration increased with silage supplementation for severe grazing (+1.0 g/kg) but decreased with silage supplementation for light grazing (-0.6 g/kg). Milk fat concentration did not differ among treatments. On average, daily grazing time (-47 min/d, i.e., -9%) and herbage intake rate (-4.9 g of DM/min, i.e., -14%) decreased when cows were supplemented, with greater grazing time reduction at severe than light grazing, and greater herbage intake rate reduction at light than severe grazing. In conclusion, the greater substitution rate and the lower 4% fat-corrected milk production when corn silage was provided at a similar postgrazing sward height rather than at a similar HA to those of unsupplemented cows explain why supplementing grazing dairy cows with conserved forages has no strong effect in practice from a production point of view.

Growth performance, nutrient digestibility, and ruminal fermentation of dairy calves fed starter diets with alfalfa hay versus corn silage as forage and soybean oil versus palm fatty acids as fat source.

The present study was intended to evaluate the effect of forage source (alfalfa hay; ALF vs. corn silage; CS) along with a supplemental fat source (soybean oil; SO vs. rumen-inert palm fatty acids; PF) on growth performance, nutrient digestibility, and ruminal fermentation in dairy calves. Forty-eight new-born Holstein female calves (3 d old) were assigned to one of 4 treatments: (1) alfalfa hay with soybean oil (ALF-SO); (2) alfalfa hay with palm fatty acids (ALF-PF); (3) corn silage with soybean oil (CS-SO); (4) corn silage with palm fatty acids (CS-PF). Starter diets had equal amounts of forage (100 g/kg dry matter; DM) and fat source (30 g/kg DM). Calves were fed a constant amount of milk (d 1 to 63) and had ad libitum access to water and starters (d 1 to 83). The lowest and greatest starter intakes during the preweaning period occurred in ALF-SO and CS-PF, respectively. This coincided with forage × fat source interaction for average daily gain (ADG) during preweaning. The forage source affected total DM intake and ADG over the entire period, body weight (BW) at weaning, and final BW with greater values in calves that received CS compared with ALF. The concentrations of total short-chain fatty acids and butyrate were increased, whereas concentration of acetate and acetate:propionate ratio were decreased in the rumen of calves fed CS compared with ALF. Feeding CS increased urinary excretion of allantoin and, as a trend, total purine derivatives (PD) and estimated microbial protein synthesis in comparison with ALF. The fat source affected starter intake, ADG, and BW postweaning with the highest values in PF. The digestibility of neutral detergent fiber, crude protein and, as a trend, organic matter were higher in calves fed PF compared with SO. Calves fed PF had lower ruminal ammonia-N concentration and urinary N excretion and greater urinary excretion of allantoin and total PD. Calves receiving SO had a lower ruminal protozoa population. In conclusion, supplementing starter diets with CS and PF is superior to ALF and SO. Interaction of the positive effects of CS and PF on performance underlines that concurrent supplementation of CS with PF is especially recommendable in young calves before weaning.

Does the time of microencapsulated sodium butyrate supplementation have any effect on the growth performance and health of Holstein dairy calves?

AbstractThe optimal feeding time of microencapsulated sodium butyrate (SB) in whole milk (WM) and starter feed on growth performance and health in dairy calves was evaluated. Forty-eight newborn Holstein calves (body weight (BW) = 39.45 ± 2.48 kg) were randomly assigned to one of the four treatment groups (12 calves per treatment; seven females and five males) in a complete randomized block design and fed (1) WM without microencapsulated SB (CON) supplementation; (2) 4 g/day SB added to WM since days 4–32 (SB-4-32); (3) 4 g/day SB added to WM since days 61–74 and an equal amount was added to starter since days 75–88 (SB-61-88) and (4) 4 g/day SB added to WM since days 4–74 and an equal amount was added to starter since days 75–88 (SB-4-88). Total dry matter intake, starter intake, BW, average daily gain and gain-to-feed were similar between treatments. Calves fed SB-4-32, and SB-4-88 had lower faecal score during pre-weaning, and overall. In addition, calves in SB-4-32 and SB-4-88 groups had fewer numbers of days with scours during the pre-weaning period, and throughout the study. Calves fed SB-61-88 had greater serum total protein during post-weaning. Post-weaning and overall albumin concentrations were greater in SB-4-32 and SB-4-88 calves and tended to be greater in the pre-weaning period compared to control calves. In general, the time of SB addition had no remarkable effect on performance but better faecal score within the pre- and post-weaning periods.