Digestion In Calves Research Articles

The influence of the probiotic “Bioseven” on indicators of survival and growth of calves in the early postnatal period

Dairy cattle breeding is one of the promising areas of agriculture. With a systematic approach and modern technologies, it is a highly profitable agrarian business that is dynamically developing. According to experts, the competitiveness and profitability of the industry can be increased due to the use of natural feed additives and preparations to obtain ecologically safe products for humans. Among them, preparations of microbiological origin are increasingly used, in particular, probiotics, which contain living microorganisms useful for the macroorganism. These drugs are used for prophylactic or therapeutic purposes. It is known that most microorganisms inhabiting the intestines are safe and do not cause diseases, but there is a constant competition between bacteria of different species for space and nutrients. The inconsistency of the microclimate parameters in the calf pens had a direct negative effect on the calf's body, especially in the early postnatal period. In particular, the deviation from the temperature balance, increased air humidity, and the presence of drafts caused a violation of the heat exchange processes of the calves' body with hypothermia and overheating of the body, and, as a result, provoked the frequent occurrence of respiratory diseases. In addition, increased air humidity and high microbial pollution caused the emergence of diseases with functional disorders in the digestive tract due to an imbalance of normal flora and increased activity of the development of transit microbes from the external environment, which negatively affected the homeostasis of the calves' body, weakened the natural resistance of calves, their growth, preservation and often led to the death of animals. Oral use of the probiotic “Bioseven” in a dose of 5.0 g (1.5·109 CFU/cm3) based on 10 kg of live weight ensured the complete preservation of the herd of young calves, accelerated their growth energy, as evidenced by exterior indicators of the animals of the experimental group against the control and probable (P < 0.05) average daily gains in live weight – 1.236 ± 0.37 kg/day versus 1.002 ± 0.41 kg/day in the control group of calves. In further studies, we used a dose of the probiotic “Bioseven” – 5.0 g (1.5·109 CFU/cm3) based on 10 kg of live weight, as the optimal dose of the experimental drug, established by the results of research. Comparative results of studies of growth indicators in the calves of the experimental group showed a significant advantage in the actual probable (Р < 0.01) increase in their live weight during the experimental period, which exceeded the similar indicators of the control by 23.6 %. The results of studies of indicators of average daily live weight gain were significantly (Р < 0.05) higher than those of control calves by 28.5 % (Р < 0.01), which testified to the effectiveness of the use of the probiotic “Bioseven” in young calves. Taking into account the obtained results, it becomes clear that the components of the probiotic drug “Bioseven” have a positive effect on the formation of cicatricial digestion in calves.

Effect of physical form of starter feed on nutrient digestibility of dairy calves

Abstract. The present experiment aimed to compare the effect of the physical form of a starter for dairy replacement calves on some rumen fermentation parameters. Nine male calves 4 days old and averaging 41.3 kg (SD = 3.6) were divided into three groups. The calves were housed in individual hutches bedded with straw. The calves were weaned at the age of 56 days of age and remained in the experiment until they reached 70 days. Three different physical forms of starter feeds were tested: 1) Ground starter – starter in meal form with coarsely ground maize (GS); 2) Pelleted starter (PS); and 3) Textured starter – a mixture of whole maize grain plus pelleted protein concentrate (TS). The ingredients and chemical composition of the three starter feeds were similar. The calves from all groups received 4 L of whole milk until 56 days of age. The liquid feed was provided twice daily from 4 to 35 days of age, and once daily from 36 to 56 days. From 35 days of age, calves were offered a free choice of alfalfa hay. OM digestibility was lower in calves that received ground starter compared to calves fed pelleted starter and textured starter. Apparent total tract digestibility of CP was the lowest in calves fed GS compared to those receiving PS and TS (P <0.05). No statistically significant difference in CP digestibility was observed between PS and TS-fed calves. EE digestibility was significantly lower in calves that received GS compared to those that received PS (P <0.05), but not different from EE digestibility in calves fed TS. The highest EE digestibility was that in PS-fed calves. CF digestibility was the highest in calves that received PS and the lowest in those fed GS, with significant differences (P <0.05). There was no significant difference in NFE digestibility among tested physical forms of starter feeds.

370 Evaluation of Nutrient Digestibility By Calves Born from Early and Late Shedding Angus Dams

Abstract Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was to investigate the nutrient digestibility of Angus calves born to cows that on average, shed early compared with calves from cows that shed later. Newly weaned, purebred Angus bull calves (early; n = 6, late; n = 6) were housed in metabolism crates for 10 d. Before the trial, calves had a 14-d adaption period to a 14% CP textured feed (CPC 14% Developer, CPC Commodities, Fountain Run, KY) and offered ad libitum Cynodon dactlyon hay and water. After 3 d crate acclimation period, urine, feces, orts, and hay samples were collected for 7 d. Concentrate was offered at 0.25% of average BW. Approximately 5% samples were taken of feces, and urine samples had 1 to 1.5% of 25% metaphosphoric acid added to prevent ammonia volatilization, and both collections were composited by animal. Orts were collected at 0600 h daily, dried, and composited by animal. Laboratory analysis included dry matter (DM), organic matter (OM), ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), Kjeldahl N (CP), and fat. Data were analyzed using the GLM procedure of SAS 9.4 in a completely randomized design with calf as the experimental unit. Significant (P ≤ 0.05) means were separated using Fischer’s protected LSD. The model for intake included average daily DM and OM (kg) and adjusted by body weight (BW%). For digestibility analysis, the model included: DM, OM, ash, NDF, ADF, hemi-cellulose (HC), CP, and fat. The N retention model included: N retained (g/d), N retained/consumed (%), and N retained/DM intake (%). There were no differences between early or late calves for DM intake (5.502 ± 0.2774 kg/d; 2.251 ± 0.1247 %BW), or OM intake (5.199 ± 0.2591 kg/d; 2.128 ± 0.1166 %BW). There were no differences in digestibility for either group for DM, OM, Ash, NDF, ADF, HC, CP, or fat (Table 1.). There were also no differences in N retention in either group of calves (3.686 ± 2.0242 g/d; 4.366 ± 2.3964 %; 0.064 ± 0.0355 %). Further research is needed in this area to adequately understand factors influencing nutrient digestibility in calves born from early and late shedding dams.

Effects of mixing a high-fat extruded pellet with a dairy calf starter on performance, feed intake, and digestibility.

During weaning, withdrawal of milk replacer is not directly compensated for by an increase in solid feed intake. Therefore, greater fat inclusion in the starter might mitigate this temporary dietary energy decline. However, fat inclusion in solid feeds may generally limit rumen fermentability and development. To address these potentially conflicting outcomes, we conducted 2 experiments to evaluate the effect of supplementing a high-fat extruded pellet mixed with a calf starter on feed intake, performance, and nutrient digestibility in calves. In experiment 1, 60 Holstein bull calves were blocked by serum IgG (2,449 ± 176 mg/dL) and date of arrival (2.5 ± 0.5 d of age). Within each block, calves were randomly assigned to 1 of 3 treatments: a standard control calf starter (CON; 3.1% fat) and mixtures of CON with 10% inclusion of 1 of 2 different high-fat extruded pellets containing 85% of either hydrogenated free palm fatty acids (PFA, 7.1% fat) or hydrogenated rapeseed triglycerides (RFT, 6.7% fat). Calves were offered milk replacer up to 920 g/d until 42 d of age, followed by a gradual weaning period of 7 d. Calves had ad libitum access to the starter diets, straw, and water. No differences were observed between CON, PFA, and RFT calves on body weight (BW) or average daily gain (ADG) until 49 d of age. From weaning (50 d) until 112 d, PFA calves had a greater BW and ADG than RFT and CON animals. Moreover, PFA calves had the highest intakes of starter, straw, calculated metabolizable energy, and crude protein after weaning. Overall, no differences were present in blood β-hydroxybutyrate and glucose concentrations between treatments; however, calves in the RFT treatment had a higher concentration of insulin-like growth factor-1. In experiment 2, 24 Holstein bull calves at 3 mo of age were assigned to 1 of 8 blocks based on arrival BW and age. Within each block, calves were randomly assigned to 1 of the 3 treatments previously described for experiment 1. Calves on the RFT treatment had the lowest total-tract apparent dry matter and fat digestibility, potentially explaining the differences in performance observed between PFA and RFT calves. Inclusion of the PFA pellet at 10% with a calf starter improved BW, solid feed, and energy intake after weaning. However, these benefits were conditioned by fat source and its digestibility.

Determination of Nutrient Digestibility in Calves Supplemented with Various Levels of Corn Gluten Feed When Consuming Forage-based Rations

Abstract The experimental objective was to determine the effect of supplementing various levels of corn or corn gluten feed (CGF) on apparent total tract nutrient digestibility in cattle consuming a forage-based ration. Twelve purebred Angus and Simmental heifers were stratified across treatments by BW and breed in a 2x2 factorial arrangement across 2 periods (n = 6/treatment). Treatments included either corn or CGF supplemented at 0.25% BW or 0.75% BW with ad libitum access to alfalfa hay. Each period lasted 21 d, with animals housed as a group and moved to individual stalls to consume supplement each morning during the first 10 d and individually thereafter. Fresh alfalfa and supplement were provided daily throughout the experiment, and feed offered and refused were recorded daily while animals were housed individually. During the final 3 d of each period, fecal samples were obtained directly from the rectum of each animal every 6-h. Samples were analyzed for neutral detergent fiber (NDF), organic matter (OM), and crude protein (CP). Data were analyzed using lm in R with significance defined at P ≤ 0.05. The statistical model included the fixed effects of supplement type, level, and their interaction, breed, and period. No differences (P ≥ 0.28) in ADG or G:F were noted among treatments. Total tract NDF, ADF, and OM digestibility did not differ among treatments, but OM and ADF digestibility tended to be greater (P = 0.10 and P = 0.06, respectively) for animals supplemented with corn. Crude protein digestibility was not influenced by supplement type (P = 0.46), but tended to be greater (P = 0.07) for animals supplemented at 0.25% BW. These results indicate that at supplement levels below 0.75% BW, supplementing cattle with CGF does not result in an improvement in apparent total tract digestibility relative to corn under the conditions of this experiment.

Supplementation of lysolecithin in milk replacer for Holstein dairy calves: Effects on growth performance, health, and metabolites

Lysolecithin is an antiinflammatory emulsifier associated with improved apparent digestibility of total dietary fat and improved feed efficiency in dairy cattle. However, it is unknown if lysolecithin (LYSO) improves performance in calves. Moreover, since many conventional milk replacers use vegetable-sourced fat (e.g., palm oil), nutrient absorption and fecal score may be affected in neonatal calves. Thus, the objective of this study was to evaluate the effects of LYSO supplemented in milk replacer on performance, metabolites, and gut health of preweaned dairy calves. Holstein calves (n = 32) with adequate passive transfer were assigned in pairs (16 blocks) balanced by birth weight, date of birth, and sex at 1 d of age to randomly receive either LYSO (mixed in 2 milk replacer feedings at a rate of 4 g/d Lysoforte, Kemin Industries Inc., Des Moines, IA) or a milk replacer control (nothing added). Both treatments were fed 6 L/d milk replacer [22.5% crude protein, 16.2% crude fat (vegetable oil fat source) on a dry matter basis with 14% solids] by bucket in 2 daily feedings for 56 d. Calves were individually housed in wooden hutches and offered a commercial calf starter (24.6% crude protein and 13.9% neutral detergent fiber) and water by bucket ad libitum. Feed refusals and calf health was assessed daily. Weights and blood metabolites (glucose, total serum protein, albumin, creatinine, triglycerides, and cholesterol) were sampled weekly, and calves completed the study before weaning at 56 d of age. The effects of LYSO on calf average daily gain, feed efficiency, and blood metabolites were evaluated using a linear mixed model with time as a repeated measure, calf as the subject, and block as a random effect in SAS (SAS Institute Inc., Cary, NC). The effect of LYSO to improve the odds of abnormal fecal score was evaluated using a logistic model. Supplementation of LYSO increased average daily gain (control 0.28 ± 0.03 kg; LYSO 0.37 ± 0.03 kg; least squares means ± standard error of the mean) and increased feed efficiency (gain-to-feed; control 0.25 ± 0.03; LYSO 0.32 ± 0.03). Similarly, LYSO calves had a higher final body weight at d 56 (control 52.11 ± 2.33 kg; LYSO 56.73 ± 2.33 kg). Interestingly, total dry matter intake was not associated with LYSO despite improved average daily gain (total dry matter intake control 1,088.7 ± 27.62 g; total dry matter intake LYSO 1,124.8 ± 27.62 g). Blood glucose, albumin, creatinine, triglycerides, and cholesterol were not associated with LYSO. Indeed, only total serum protein had a significant interaction with LYSO and age at wk 5 and 6. Moreover, control calves had a 13.57 (95% confidence interval: 9.25-19.90) times greater odds of having an abnormal fecal score on any given day during the diarrhea risk period from d 1 to 28. The inclusion of LYSO as an additive in milk replacer in a dose of 4 g/d may improve performance, and calf fecal score, preweaning. Further research should investigate the mechanisms behind the effects of LYSO on fat digestibility in calves fed 6 L/d of milk replacer with vegetable-sourced fat.

Influence of probiotics “Immunobacterin-D” on biocenoses and development of the gastrointestinal tract of calves

The paper presents the results of an experiment on the use of enzyme-probiotic supplement “Immunobacterin-D” for calves in the first two months of life. Probiotics are used in animal husbandry for the prevention and treatment of infectious diseases, increase immunity, correction of the microflora after antibiotic therapy, prevention of stress, increase growth. The study was conducted in a private farm in the Lyubar district of Zhytomyr region, which kept cattle of different ages. In a randomized controlled trial, two experimental groups of six animals were formed in each on the principle of analogues. One group was a control. Calves of the experimental group from the second day after birth were fed together with colostrum “Immunobacterin-D” at the rate of 3 grams per animal. For the first five days, the enzyme-probiotic supplement was given to the calves once a day during the morning feeding, and in subsequent studies, once every two days for a month. The results of the studies show that no case of diarrhea was registered among calves receiving the enzyme-probiotic supplement “Immunobacterin-D”. Among the animals of the control group, 66.7 % had digestive disorders – dyspepsia. Subsequently, such animals had a lower growth rate. Enzyme-probiotic supplement “Immunobacterin-D” also contains Bacillus Subthilis, Bacillus Licheniformis and enzymes and protease and lipase – it provides a polyvector effect in the digestive tract in general and scarring in particular. It was found that on the fourteenth day of feeding probiotic-containing drug “Immunobacterin-D” to calves of the experimental group, the number of bacteria probably increased by 83.5 %; ciliates – by 65.0 %; endodynomorphs – by 24.3 %. After one month of the experiment, the number of bacteria in the experimental group probably increased by 94.3 %; ciliates – by 40.5 %; endodynomorphs – by 26.7 %, compared with the control (P < 0.001). The obtained data of registration of the first chewing gum in calves prove that the components of the enzyme-probiotic supplement “Immunobacterin-D” accelerate the population of microflora and the development of scar digestion in calves 2.5 times compared to calves in the control group. Prospects for further research are to study the effect of enzyme-probiotic supplement “Immunobacterin-D” on the indicators of scar fermentation of calves.

Effect of extruded grain feed, with the preliminary germination of rapeseed, on the cicatricial digestion of dairy cows and calves

This article describes the scientific and production experience conducted in the Druzhba LLC, of the Buinsky district of the Republic of Tatarstan. The purpose of the scientific and production experiment is to study the effect of extruded feed, with the preliminary germination of rapeseed in a 0.05 % nicotinic acid solution, on the cicatricial digestion of calves and dairy cows. During the experiment, it is found that feeding calves and dairy cows with extruded feed with preliminary germination of rapeseed in a 0.05 % nicotinic acid solution had a positive effect on cicatricial digestion, contributing to an increase in ammonia to 8.7 and 7.9 %, acetic acid – 12, 6 and 11.5 % and propionic – 13.4 and 12.6 % acids, with a decrease in butyric acid – 12.8 and 10.4 %, an increase in the total microbial number – 8 4.0 and 16.3 %, in including cellulolytic bacteria – 11.6 and 14.3 %, ciliates – 13.4 and 12.9 %, as well as the enzymatic activity of cicatricial microflora, respectively accordingly, in comparison with the control and the group where the grain feed is subjected to only one extrusion. Thus, the use of extruded feed with pre-germinated rapeseed in feeding calves and dairy cows improved the underlying indices of cicatricial digestion compared with the control group of animals fed with non-extruded feed and the group of animals fed with extruded feed.

Використання замінників цільного молока в корекції процесів рубцевого травлення у телят

The formation of cicatricial processes in calves is an important component of the process of growing viable animals, which we studied under the conditions of introduction into the diet of three groups of calves whole milk substitutes for three months. Correction of cicatricial digestion of calves of the early neonatal period significantly increases its parameters and affects the metabolism in animals. It was found that at the end of the equalization period the content of amylolytic, proteolytic, cellulosolytic microorganisms and their specific activity in the contents of the scar of animals of the experimental groups fluctuated slightly. The quantitative composition of rumen microorganisms determined the content of the total mass of rumen microorganisms and the total concentration of volatile fatty acids in the rumen, which ranged from 9.13±0.12 to 9.45±0.24 mmol/100 ml. The content of total, residual and protein nitrogen in the scar content of calves of all groups was almost the same at the end of the equalization period. The introduction into the diet of calves of the neonatal period of feed mixtures Lactophyte-T and Lactophyte-TP increased the activity of the main groups of microorganisms of the rumen and, most importantly – cellulosolytic microorganisms. In calves of the experimental groups, the content of volatile fatty acids and protein nitrogen in the contents of the scar increased. Volatile fatty acids in the blood of calves of the experimental groups were found in 1.08–1.28 times more than in calves of the control group (p<0.01). The content of ketone bodies in the blood of calves of the third group was significantly lower by 1.14 times, urea was lower by 1.12 times (p<0.05). The increase in the activity of scar fermentation processes contributed to the fact that the increase in body weight in calves of the experimental groups was during the experimental period in 1.36–1.57 and 1.42–1.57 times (p<0.01), more than in the control animals. In the future, research on the formation and correction of scar digestion will provide the body of animals with full metabolic metabolites, microbial protein and volatile fatty acids and promote the growth and development of animals.

Effects of colostrum and milk replacer feeding rates on intake, growth, and digestibility in calves

Newborn Holstein male calves (n = 50) born on a single dairy farm were assigned randomly at birth to receive 3 feedings of 1.8 L of pooled maternal colostrum (MC) at 1, 6, and 12 h of age or 1 feeding of 500 g of a colostrum replacer reconstituted to 1.8 L at 1 h of age, followed by 2 feedings of 227 g of a commercial milk replacer (MR) reconstituted to 1.8 L at 6 and 12 h of age (CR). All feedings were administered by esophageal feeder. At 2 to 3 d of age, calves were transported to the experimental facility and assigned within colostrum group to receive 0.66 kg/d dry matter (DM) of MR to 39 d, and then 0.33 kg/d to 42 d (MRM) or 0.77 kg/d of MR DM to d 13, 1.03 kg/d for 22 d, and 0.51 kg/d for 7 d (MRH). The MR contained 25.8% crude protein and 17.6% crude fat (DM basis) and was based on whey proteins and lard as the primary fat source. Calf starter (21.7% crude protein, 15.7% neutral detergent fiber, 37.4% starch, DM basis) and water were available for ad libitum consumption throughout the 56-d study. Serum IgG and total protein were measured at 2 to 3 d of age. Intakes of MR and calf starter were monitored daily. Calf health and fecal scores were also monitored daily. Body weight was measured weekly, and hip width and body condition score were monitored every 2 wk. Digestion of DM, organic matter, crude protein, and ether extract were determined at 1 and 3 wk from 5 calves randomly selected within treatment and using chromic oxide as a digestibility marker added to the MR. Calves fed CR had lower serum IgG and total protein than calves fed MC. Also, calves fed CR grew more slowly, consumed less calf starter, and were less efficient to 56 d than calves fed MC. The number of days calves were treated with veterinary medications was higher when calves were fed CR. Calves fed MC-MRH gained more BW than other calves from 3 to 8 wk of age. Calves fed CR-MRH consumed less calf starter than other calves during wk 7 and 8. Digestion of nutrients at 1 and 3 wk of the study was unaffected by type of colostrum or level of MR fed and did not change from 1 to 3 wk. Over the first 2 mo of life, the calves fed MRH consumed less calf starter than calves fed MRM, but average daily gain or hip width change did not differ. One feeding of CR followed by 2 feedings of MR in the first 24 h likely reduced absorption of IgG from CR and contributed to differences in health and growth. Differences in animal performance observed in this study were unrelated to MR digestibility.

Effects of free-choice hay and straw bedding on digestion of nutrients in 7-week-old Holstein calves

ABSTRACT Objective Bedding with long straw improves animal health and performance but could affect digestibility measurements if calves consume the bedding. Feeding hay with calf starters is common practice; however due to the limited capacity of the young calf’s rumen, high levels of roughage can lead to decreased DMI, digestibility, and ADG. The objectives of this study were to evaluate the effect of long-straw bedding and free-choice hay on nutrient digestibility in calves less than 2 mo old. Materials and Methods Sixteen calves (45.4 ± 1.18 kg of BW, 3 d of age) were bedded on long wheat straw or on rubber mats and fed diets with or without free-choice, long-grass hay. Calves were fed a 25% CP, 17% fat milk-replacer powder at 0.66 kg of DM 2 times per day for 35 d and then 0.33 kg of milk replacer 1 time per day for 7 d. Milk replacer was diluted to 14% DM. Calves were fed free-choice textured starter and water for the entire 56-d trial. Hay was 5.4% CP and 62.8% NDF (DM basis). Digestibility was estimated on d 47 to 51 using acid insoluble ash in feeds and feces as an internal marker. Results and Discussion Hay intake varied and reduced the digestion of dietary DM, OM, CP, and fat by calves. As hay intake increased, digestion of OM decreased linearly. Implications and Applications Long wheat straw as bedding did not change estimates of digestion in young calves consuming coarse, textured starter, whereas moderate- to low-quality hay intake reduced digestion.

Effects of Flavonoids from Mulberry Leaves and Candida tropicalis on Performance and Nutrient Digestibility in Calves

Effects of Flavonoids from Mulberry Leaves and Candida tropicalis on Performance and Nutrient Digestibility in Calves

1624 Use of fecal starch as an indicator of starch digestibility and starter intake in preweaned dairy calves

Fecal starch (FS) has been used as a tool to evaluate starch digestibility in lactating dairy cows and feedlot steers. Some on-farm advisors are also using FS in a similar way to evaluate solid feed digestibility in preweaned dairy calves. Our objective was to evaluate the relationship of FS with starter intake and starch digestibility in preweaned dairy calves. Male Holstein calves initially 43 ± 2.9 kg BW from a single farm (N = 35) were fed different amounts of milk replacer ranging from 0.66 to 1.1 kg DM daily (27% CP and 17% fat) and weaned by 7 wk of age. Starters contained 37% whole corn, 20% whole oats, 35% protein pellet, and 3% molasses and contained 43% starch (first set) and 38% starch (second set). Fecal grab samples were taken from calves at 3 (n = 20), 6 (n = 20), and 8 wk (n = 35) of age. Twelve fecal samples per calf were taken via rectal palpation over a 5-d period each week, frozen daily, combined on an equal wet-weight basis, and subsampled for analysis. Chromic oxide was used as an external digestibility marker at 3 and 6 wk, whereas AIA was used as an internal marker at 8 wk. Milk replacer and starter intakes (offered and refused) were recorded daily during collection. Linear regression analysis of starch digestibility (%) and dry feed intake (kg/d) vs. fecal starch (%) were determined using PROC REG of SAS. At 3 wk of age, starch digestibility increased (y = 0.69x + 40.80; R2 = 0.53, P < 0.01) and starter intake decreased (y = −0.01x + 1.32; R2 = 0.20, P = 0.05) with increasing FS. At 6 wk of age, starch digestibility (P = 0.11) and starter intake (P = 0.96) were not related to FS. At 8 wk of age after calves were weaned, starch digestibility decreased as FS increased (y = −0.62x + 99.7; R2 = 0.86, P < 0.01), whereas FS and starter intake were not related (P = 0.17), a relationship in contrast to the previously observed result in calves still consuming milk replacer. In the current study, results suggest that FS was not a good estimate of starch digestion or dry feed intake in the preweaned calf but has promise for evaluating starch digestibility in calves after weaning.

Influence of teat flow rate in commercial milk feeding systems on calf digestion and performance

SummarySeventy two, one day old Friesian heifer calves were fed whole milk either via regular or slow release teats on commercial calfeteria systems (Milkbar, McInnes Manufacturing Limited, Waipu, New Zealand) for 42 days. For the entire period, the consumption time for the calves fed on the regular flow rate teat calfeterias was twice as fast as for those fed using the slow teats. Meal intake was numerically higher for the calves fed milk using the slow teats. At day 42, calves on the slow teats had a strong trend towards higher daily gain. At 14 days of age, visual differences in curding were seen in the abomasum of culled calves, with the fast teat-fed animals having large lumps of curded milk surrounded by watery liquid, whereas the slow teat-fed calves had much smaller particle sized curding in thicker fluid. Lactose digestion in the stomach was significantly higher for the calves fed using the slow teats, and there was a strong trend for higher levels of free protein in the ileum. Using slow flow rate teats to feed calves from day old to weaning appears to have an important impact on digestive processes in the immature gut. Such improvements in digestion and rumen development in young calves may assist in the digestion of milk and other feeds, leading to improved growth performance. Under farm conditions, slow release teat systems may reduce scours and other digestive problems in young calves during peak milk intake (up to 15 d of age), due to increased ileal digestion of nutrients, preventing undigested nutrient flow to the hind gut. It may also reduce cross-sucking behaviour in calves, which is undesirable.

Effect of varying ruminally degradable to ruminally undegradable protein ratio on nutrient intake, digestibility and N metabolism in Nili Ravi buffalo calves ( Bubalus bubalis)

Four Nili-Ravi buffalo calves (100 ± 4 kg) were used in 4 × 4 Latin Square Design to evaluate the influence of varying ruminally degradable protein (RDP) to ruminally undegradable protein (RUP) ratio on dry matter intake (DMI), digestibility and nitrogen (N) metabolism. Four experimental diets A, B, C and D were formulated to contain RDP:RUP of 70:30, 65:35, 60:40 and 55:45, respectively. The calves were fed ad libitum. Dry matter intake by calves fed C diet was higher ( P < 0.05) than those fed D diet and lower ( P < 0.05) than calves fed A diet, however, it was similar to those fed B diet. There was a linear decrease ( P < 0.01) in DMI with decreasing the RDP to RUP ratio. Similar trend was noticed in crude protein (CP) intake. Neutral detergent fiber (NDF) intake was significantly different across all treatment. The decrease in CP and NDF intake was due to decreasing trend of DMI. Dry matter (DM) digestibility in calves fed A and B diets was higher ( P < 0.05) than those fed C and D diets. A linear decrease ( P < 0.01) in DM digestibility was observed with decreasing the RDP to RUP ratio. Crude protein digestibility remained unaltered across all treatments. Neutral detergent fiber digestibility was higher in calves fed A and B diets than those fed C and D diets. Higher NDF digestibility in calves fed A and B diets was due to higher level of dietary RDP that might resulted in higher ruminal ammonia concentration which stimulate activity of cellulytic bacteria and ultimately increased NDF digestibility. The N retention (g/d) was similar among the calves fed B, C and D diets, however, it was higher ( P < 0.05) than those fed A diet. Decreasing the RDP to RUP ratio resulted in linear increase ( P < 0.01) in N retention. The N retention, as percent of N intake was significantly different across all treatments. Decreasing RDP to RUP ratio resulted in linear increase ( P < 0.01) in N retention, as percent of N intake. A similar trend was noticed in N retention, as percentage of N digestion. Blood urea nitrogen (BUN) concentration in calves fed B diet was higher ( P < 0.05) than those fed D diet and was lower ( P < 0.05) than those fed A diet, however, it was not different from calves fed C diet. Decreasing dietary RDP to RUP ratio resulted in linear decrease ( P < 0.05) in BUN concentrations. The decrease in BUN concentration was because of decreasing level of dietary RDP. The N retention can be increased by decreasing RDP to RUP ratio in the diet of growing buffalo calves and diet containing RDP to RUP ratio 55:45 is considered optimum regarding N retention in buffalo calves.

Influence of an Anaerobic Fungal Culture (Orpinomyces sp.) Administration on Growth Rate, Ruminal Fermentation and Nutrient Digestion in Calves

The study was to see the effect of administration of ruminal fungi on feed intake, growth rate, rumen fermentation and nutrient digestion of calves (TharparkarxHolstein-Friesian, average age: 10 months, average body weight: 130 kg). The 6 calves in first group were fed a mixture consisted of 50% wheat straw and 50% concentrate (Maize 62%, Groundnut cake 35%, Mineral mix. 2% and Common salt 1%) along with 1 kg green oats animal - 1 day - 1 while second group calves were fed the above-mentioned diet in addition to a dose of 160 ml (10 6 CFU/ml) fungal culture calf 1 week - 1 . The average dry matter intake per day was slightly lowered in fungal fed calves yet feed conversion ratio was higher. The average daily weight gain was significantly higher (15.37%) in fungal administered group as compared to control. The nutrient digestibility was increased for crude fibre, NDF and ADF with fungal administration. Digestible energy value of straw-based diet in terms of percent TDN also increased. The pH and NH 3 -N were lower whereas TVFA, total-N, TCA-N and number of zoospores were higher in rumen liquor in fungal administered group.

Digestion criteria in nursing beef calves supplemented with limited levels of protein and energy.

This study was conducted with grazing nursing calves (197 kg) to determine the effects of 1) limiting creep feed intake and 2) increasing the concentration of ruminal escape CP in creep feed at a limited level of creep feed intake on fescue and milk intake, ruminal NDF digestion, and total tract digestibility in calves fed high-quality, freshly harvested fescue. The treatments were 1) control (no creep feed), 2) limited intake of creep feed (.60 kg/d) having a moderate concentration of CP (13%), 3) limited intake of creep feed (.60 kg/d) having a high concentration of CP (35%), and 4) unlimited (high) intake (1.62 kg/d) of the same creep feed fed in Treatment 2. Forage OM intake was negatively correlated (r = -.995, P less than .05) with level of creep feed OM intake, whereas milk OM intake was not affected by level of creep feed intake. Decreases in ruminal fiber digestion and total tract NDF digestion caused by unlimited creep feeding were partially avoided by limiting creep feed intake. Digestible OM intake increased by .47 kg per kilogram of creep feed OM intake.

HIGH-ROUGHAGE RATIONS WITH OR WITHOUT MONENSIN FOR VEAL PRODUCTION. II. RATION DIGESTIBILITY

Thirty-six calves 19–20 wk old (149 ± 17 kg) and forty-eight rams (46 ± 4 kg) were used in two experiments to study the effects of two ground roughages (alfalfa and timothy), their proportion in pelleted rations (20, 40 and 60%) and addition of monensin (0 and 33 ppm) on ration digestibility. Calves and rams were fed the test rations ad libitum for a period of 8 and 5 wk, respectively, before the digestibility trial. Dry matter (DM) digestibility in both species and energy digestibility in calves were significantly higher for the rations containing alfalfa than for those containing timothy; however, digestibility of crude protein (CP) in both animal species and of cell walls (NDF) in calves was lower in alfalfa rations. The two trials revealed an increase in digestibility of acid detergent fiber (ADF) and of cell wall (NDF) fractions but a reduction in DM digestibility when the roughage content in the rations increased; the reduction in DM digestibility was larger with timothy than with alfalfa. Addition of monensin did not affect digestion coefficients of DM, ADF and NDF in calves and rams on average. However, a monensin × roughage level interaction indicated a decrease of ADF and NDF digestibility in calves fed 20% roughage and an increase of ADF and NDF digestibility in calves fed 60% roughage. Key words: Alfalfa, timothy roughage level, monensin, calf, sheep

Effects of Frequency of Offering and Type of Supplemental Forage on Intake and Digestion in Calves Consuming Endophyte-Infected Fescue Hay

Two experiments were conducted to determine the effects of frequency of offering and type of supplemental forage on intake and digestion in calves consuming endophyte-infected fescue hay (I). In Exp. 1, five Holstein steers, averaging 128 kg body weight (BW), were used in a 5 X 5 Latin square experiment. All steers were given free access to I in the afternoon. Morning meals consisted of 1) ad libitum access to I daily (control), 2) .5% BW of Bermuda-grass hay (BG) daily, 3) 1.0% BW of BG every 2nd d, 4) 1.5% BW of BG every 3rd d and 5) 2.0% BW of BG every 4th d. Steers receiving BG consumed less (P less than .01) I and more (P less than .01) total dry matter (DM) than did steers given I alone. Within treatment, I intake was similar (P greater than .10) among days of the feeding cycle without BG. Organic matter (OM) digestion was lower (P less than .05) with than without BG. In Exp. 2, 12 beef calves (Angus and Hereford X Angus; 6 mo of age, 155 kg initial BW) were used in a completely randomized-design experiment. Calves were given ad libitum access to I daily (control) or to BG or wheat hay (WH) on d 1 and I the following 3 d. Hay (I, BG or WH) intake d 1 of the feeding cycle was higher for BG and WH than for the control treatment (16 and 45%, respectively) and higher for WH than BG (25%; P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Functional Fish Protein Concentrate in Milk Replacers for Calves

A fish protein concentrate with improved function properties (i.e. water-holding and emulsification capacity) has been tested in milk replacers for calves as the principal source of protein in a semisynthetic diet and with dried whey in a practical diet. The fish protein concentrate did not cause digestive problems, and the calves remained entirely healthy when fed the fish protein concentrate as the principal source of protein from 3 to 63 days or together with dried whey from 2 to 12 wk of age. Apparent protein digestibility in calves between 7 and 63 days of age was curvilinearly related to age and was 90.5 and 96.1% for fish and milk protein. Practical milk replacers with the fish protein concentrate and dried whey had similar nutrient and energy digestibility but gave slightly lower nitrogen retention and growth rate compared with an all-milk milk replacer when fed as the sole feed to preruminant calves. When fed together with concentrate and hay to replacement calves, a milk replacer with fish protein concentrate and dried whey gave similar performance to an all-milk milk replacer.