Calf Performance Research Articles

Effects of corn processing index and forage source on performance, blood parameters, and ruminal fermentation of dairy calves

The objective of this study was to investigate the effects of corn processing index (CPI)—particularly at 70% and 85%—in starter feed in combination with the provision of forage, either alfalfa hay (AH) or wheat straw (WS), on feed intake, growth performance, rumen pH, and blood metabolites of dairy calves. Forty-eight male Holstein calves (43.0 ± 1.5 kg body weight) were randomly assigned (n = 12 calves per treatment) to one of four dietary treatments: (1) a textured starter diet containing 70% CPI and AH (70CPIAH), (2) a textured starter feed containing 70% CPI combined with WS (70CPIWS), (3) a textured starter feed containing 85% CPI and AH (85CPIAH), (4) a textured starter feed containing 85% CPI combined with WS (85CPIWS). Intake of starter feed (TMR) and milk was individually monitored and recorded daily, while body weight was measured weekly. On days 30 and 65, blood samples were collected from all calves 3 h after morning feeding. No interaction was detected between the CPI of starter feed diets and forage provision for starter intake, dry matter intake (DMI), metabolizable energy intake (MEI), feed efficiency (FE), average daily gain (ADG), and body weight (BW). The preweaning and overall DMI, preweaning, postweaning and overall FE and ADG, preweaning and overall starter intake, preweaning and overall ME intake, and postweaning and overall BW were greater for calves fed 85CPI than those fed 70CPI starter diets. Postweaning and overall ADG and postweaning FE were greater in calves fed WS than those fed AH. Body length and hip width were greater for calves offered 85CPI than in fed 70CPI. Wheat straw supplementation increased rumen pH at day 65 in calves fed 70CPI, but not in those fed 85CPI. No interaction was found between the CPI in the starter feed diet and the forage source for starter intake and DMI, MEI, FE, and BW. The results showed that including corn with 85% processing index in dairy calf starters improved their growth performance.

Response of calves fed starters based on either steam-flaked corn grain or steam-flaked barley grain to dietary protein content in Holstein dairy calves

We hypothesized that steam-flaking the high-starch grains can stimulate ruminal microbial activity and reduce cecal fermentation due to lowering starch escaping in to hind-hut of young calves. Therefore, the current study evaluated the effect of steam-flaking the grains (corn grain vs. barley grain) with either 18% (18CP) or 22% (22CP) dietary protein content (dry matter basis) on growth performance, microbial protein synthesis (MPS) and inflammatory markers in young calves. Female Holstein calves (48 calves with 3 d of age) were assigned randomly to the following treatments: SFC-18CP, SFC-22CP, SFB-18CP, and SFB-22CP (n = 12, each). Milk feeding schedule was identical among treatments until weaning (d 53), and calves had ad-libitum access to water and starters until the final day of experiment (d 73). Feeding SFC increased starter intake compared to calves fed SFB diet (p = 0.05; pre-weaning, have greater feed efficiency (tendency, p = 0.07; post-weaning), better fecal score (p = 0.01), and higher hip height (p = 0.03; post-weaning) compared to calves fed SFB diet. However, ruminal pH was lower (p = 0.04; pre-weaning), heart girth was smaller (p = 0.02), and post-weaning circulating tumor necrosis factor-α was greater (TNF-α, p = 0.03) for calves fed SFB compared to calves fed SFC diet. Feeding 22CP compared to 18CP diet improved hip height at weaning time (p = 0.01) and reduced pre-weaning serum amyloid A (SAA, p = 0.04). With respect to the interaction, results indicated that higher ADG (p = 0.04) and subsequently higher BW (p < 0.05) was detected for calves fed SFC along with 22CP diet compared to other experimental arrangements. The calves fed SFB along with 18CP diet had lower withers height (p = 0.01), lower urinary allantoin (p = 0.02), and MPS (p = 0.04); but higher TNF-α (p = 0.01; pre-weaning) and higher SAA (p = 0.04; post-weaning) compared to other experimental treatments. Based on the results obtained in the current study, feeding SFC can be more favorable diet than SFB diet in young calves due to improve ruminal microbial activity and more favorable immune function. Furthermore, results suggest that feeding steam flaked corn grain with 22CP diet had positive interaction resulted in higher microbial protein production and growth performance of young calves. Optimal processing method applied for high-starch grains to increase ruminal fermentation and prevent starch escaping in to the hind-gut of young calves for reducing cecal fermentation needs to be more evaluated in milk-fed calves.

Impact of graded levels of coated calcium butyrate on growth performance and serological indices during pre-weaning stage in Holstein calves.

The study aimed to analyze the impact of calcium butyrate supplementation in calf starter on growth performance indices associated with early rumen development to decrease the volume of milk or milk replacer feeding and enhance early starter intake in Holstein calves. For this purpose, twelve Holstein calves were randomly assigned into three treatments (n = 4/treatment); a control without coated calcium butyrate, T1, and T2 treatments supplemented with coated calcium butyrate 3g and 6g per day/head, respectively. Body weight was measured at days 7, 14, 21, 28, 35, 42, 49, and 56 of the trial, and the average daily weight gain and feed conversion ratio were determined. Blood samples were collected at 14, 28, 42, and 56days of trial for serological parameters. Gut morphometry was performed at the end of trial at slaughtering by collecting duodenal samples. Furthermore, the meat was also evaluated for its quality parameters including pH and tenderness after slaughtering. The results indicated that the feed intake, average daily weight gain, feed conversion ratio, and gut morphometric parameters involving villus height and crypts depth of calves were improved in coated calcium butyrate-supplemented groups. Furthermore, the supplementation of calf starter with coated calcium butyrate significantly enhanced serum concentrations of glucose and total protein. Besides, Beta hydroxy butyrate (BHBA) levels of blood were also found to be elevated in both treatment groups. However, it was revealed that coated calcium butyrate supplementation had no significant effect on meat quality parameters. In conclusion, the supplementation of calf starter with coated calcium butyrate could improve calf performance.

Effect of Supplementation Garlic Powder (Allium sativum) in the Growth Parameters of Sahiwal Calves

The present experiment was conducted at Sahiwal Cattle Farm, College of Veterinary Science, Assam Agricultural University, Khanapara, Guwahati, Assam, India for a period of 120 days from July to November, 2022. to investigate the effect of supplementing garlic powder (Allium sativum) on the performance of Sahiwal calves. Twelve healthy Sahiwal calves of both sexes of similar age and body weight were allocated to two experimental groups, control and treatment with six animals in each group. Calves of both groups were fed with a standard basal diet consisting of concentrate, green fodder, and paddy straw. While in the treatment group, garlic powder was supplemented @ 250 mg kg-1 body weight along with concentrate feed. The experiment was conducted as a feeding trial for eight fortnights and a digestibility trial thereafter for five days in the two experimental groups. The statistical analysis revealed a highly significant differences (**p&lt;0.01) in body weight of the calves, fortnightly body weight gains up to 8th fortnight and the dry matter intake of the calves. Statistical analysis also revealed highly significant (**p&lt;0.01) differences in the conformation traits when compared between the groups with highly positive correlation with the body weight of the calves. Further it can be concluded that the supplementation of garlic powder at dosage of 250 mg kg-1 body weight in the Sahiwal calf ration is beneficial in terms of body weight gain, feed conversion ratio, body confirmation traits, and economic of feeding.

A Preliminary Study of the Potential Molecular Mechanisms of Individual Growth and Rumen Development in Calves with Different Feeding Patterns.

At present, it is common to feed calves with "Concentrate", "Concentrate + hay" and TMR "Total Mixed Rations" feeding patterns in China, which achieved well feeding efficiency, but the three feeding patterns molecular regulation mechanism in actual production is still unclear. The study aimed to explore the most suitable feeding pattern for Chinese Holstein calves to improve the rumen fermentation function and growth performance of calves. In this regard, the interactions between rumen microorganisms and host metabolism were investigated. The rumen volume and weight of calves in the GF group were significantly higher than those in the GFF and TMR groups (p < 0.05), and the rumen pH of calves in the GF group was 6.47~6.79. Metagenomics analysis revealed that the rumen microbiome of GF and GFF calves had higher relative abundances of Methanobrevibacter, Methanosphaera, and Methanolacinia (p < 0.05). Prevotella multisaccharivorax was significantly more abundant in the rumen of GF calves (p < 0.05), indicating that GF group calves had a stronger ability to ferment sugars. Notably, in the pyruvate metabolic pathway, phosphoenolpyruvate carboxylase was significantly up-regulated in GF calves compared with the TMR group, and pyruvate-phosphate dikinase was significantly down-regulated. Metabolomic results showed that Ursodeoxycholic acid was significantly up-regulated in GF calves, and most of the differential metabolites were enriched in Bile secretion pathways. The association analysis study found that the microorganisms of Prevotella and Ruminococcaceae might cooperate with the host, which was helpful for the digestion and absorption of lipids and made the calves have better growth. The three feeding modes had similar effects, but the 'GF' feeding pattern was more beneficial to the individual growth and ruminal development regarding ruminal morphology, contents physiology and microorganisms. Furthermore, the synergistic effect of rumen microorganisms and the host could more effectively hydrolyze lipid substances and promote the absorption of lipids, which was of great significance to the growth of calves.

Growth Performance and Feed Intake Assessment of Italian Holstein Calves Fed a Hay-Based Total Mixed Ration: Preliminary Steps towards a Prediction Model.

The aim of this study was to evaluate the effects of a complete hay-based total mixed ration (TMR) for calves, focusing on their feed intake, animal growth performance, and fecal output, and to develop a preliminary estimation equation for solid feed intake and body weight in Holstein heifer calves. Twenty female Italian Holstein calves (37.14 ± 2.72 kg) born between February and July were studied from the day of birth until 77 days of age. From the fourth day of life, they were fed 3 L/day of pasteurized milk twice daily and supplemented with the same hay-based TMR. The data on feed intake, fecal characteristics, and growth performances were collected and showed that these calves had adequate parameters. Moreover, the data collected was used to create equations to predict body weight and solid feed intake using a mixed model. The goodness of fit of the developed equations was evaluated by coefficients of determinations (R2). The equation obtained shows high R2 (0.98 for solid feed intake and 0.99 for calf weight), indicating the satisfactory precision and accuracy needed to predict female calves' body weight and solid feed intake.

Effect of once-a-day milk feeding on behavior and growth performance of pre-weaning calves.

The objectives of the present study were to evaluate the effects of once-a-day milk feeding on growth performance and routine behavior of preweaning dairy calves. At 22nd day of age, twenty-four Holstein calves were randomly assigned to one of two treatment groups (n = 12/treatment) based on milk feeding frequency (MF): i) 3 L of milk feeding two times a day; ii) 6 L of milk feeding once a day. The milk feeding amount was reduced to half for all calves between 56 and 60 days of age and weaning was done at 60 days of age. To determine the increase in weight and structural measurements, each calf was weighed and measured at 3 weeks of age and then at weaning. The daily behavioral activity of each calf was assessed from the 22nd day of age till weaning (60th day of age) through Nederlandsche Apparatenfabriek (NEDAP) software providing real-time data through a logger fitted on the calf's foot. There was no interaction (p≥0.17) between MF and sex of the calves for routine behavioral parameters, body weight and structural measurements. Similarly, there was no effect of MF on routine behavioral parameters, body weight and structural measurements. However, the sex of the calves affected body weight gain in calves. Male calves had 27% greater total body weight and average daily gain than female calves. There was no effect of the sex of the calves on behavioral measurements. Collectively, in the current study, no negative effects of a once-a-day milk feeding regimen were found on routine behavioral and growth parameters of preweaning calves in group housing. Once-a-day milk feeding can be safely adopted in preweaning calves from 22nd day of age.

Feeding colostrum and transition milk facilitates digestive tract functionality recovery from feed restriction and fasting of dairy calves

The objective of this study was to evaluate the digestive tract recovery and metabolism of feeding either bovine colostrum (BC), transition milk (TM), or milk replacer (MR) after an episode of feed restriction and fasting (FRF) in dairy calves. Thirty-five Holstein male calves (22 ± 4.8 d old) were involved in a 50-d study. After 3 d of feeding 2 L of rehydration solution twice daily and 19 h of fasting (d 1 of study), calves were randomly assigned to one of the 5 feeding treatments (n = 7): calves were offered either pooled BC during 4 (C4) or 10 (C10) days, pooled TM during 4 (TM4) or 10 (TM10) days, or MR for 10 d (CTRL) at the rate of 720 g/d DM content. Then, all calves were fed the same feeding program, gradually decreasing MR from 3 L twice daily to 2 L once daily at 12.5% DM until weaning (d 42), and concentrate feed, water, and straw were offered ad libitum until d 50. Citrulline, Cr-EDTA, β-hydroxybutyrate (BHB), and nonesterified fatty acids (NEFA) in serum and complete blood count (CBC) were determined on d -3, 1, 2, 5, and 11 relative to FRF, except BHB and NEFA at d -3. Volatile fatty acids (VFA), lactoferrin (LTF), IgA, and microbiota (Firmicutes to Bacteroidetes ratio and Fecalis prausnitzii) were analyzed in feces on d 5 and 11 before the morning feeding. Health scores were recorded daily from d -3 to d 14 as well as d 23 and 30. Feed concentrate, MR, and straw intake were recorded daily, and body weight on d -3, 1, 2, 5, and 11 and weekly afterward. Calf performance, intake, serum Cr-EDTA, CBC, fecal LTF concentrations and microbiota parameters were similar among treatments throughout the study. Serum NEFA concentrations were greater in TM4, TM10 and C10 calves compared with the CTRL ones from d 2 to 11, and after the FRF, serum concentrations of BHB were lower in CTRL calves than in the other treatments, and on d 11, serum BHB concentrations in the long treatments (C10 and TM10) remained greater than those in the shorter ones (C4 and TM4) and CTRL. Serum citrulline concentrations were similar on d -3 and 1 in all treatments, but they were greater in C4, C10, TM4, and TM10 on d 2 and 5, and on d 11 they were only greater in C10 and TM10 than in CTRL calves. Fecal IgA concentrations tended to be greater in C10 than in CTRL, TM4, and TM10 calves, and in C4 and TM10 than in CTRL animals. Fecal propionate proportion was lesser in C10 than in CTRL, TM4, and TM10 calves, while butyrate was greater in C4 and C10 than in TM4 and CTRL calves. The proportion of non-normal fecal scores of C10 fed calves was greater than TM4 and TM10 calves. Results showed that TM and BC may help to recover intestinal functionality, provide gut immune protection, and increase liver fatty acid oxidation in calves after a FRF episode.

How benchmarking motivates colostrum management practices on dairy farms: A realistic evaluation

This study used realistic evaluation to determine how, and in which circumstances, providing dairy farmers with benchmarked data on their calves can motivate improved colostrum management practices. Dairy farmers from British Columbia, Canada were recruited through 2 veterinary clinics that offered benchmarking of calf data as part of their services. For approximately 8 wk, blood samples were collected from newborn calves to evaluate serum total protein concentrations as an indicator of the effectiveness of the farmer's colostrum management. These data were analyzed separately for heifer calves ("replacement calves"), and non-replacement calves including males and beef crossbred females ("surplus calves"). The results of these analyses were benchmarked against other participating herds and presented to dairy farmers (n = 27) by their herd veterinarian (n = 7). Follow up interviews were conducted separately with the farmers and veterinarians after each meeting to determine their perspectives on the utility of this benchmarking strategy. Therefore, a total of 42 interviews were coded and realistic evaluation was used to determine common contexts and mechanisms that contributed to the success or failure of the benchmark meeting, with success characterized by farmers' expressed intention to improve their colostrum management practices. Four important contexts were identified that influenced the outcome of the benchmark meetings: (1) farm resources (e.g., facility limitations), (2) the farmer's perception of their calf performance, (3) management strategies, and (4) the farmer's personal values. Depending on these contexts, some farmers intended to improve their calf care practices based on resources the benchmark meeting provided, which included illustrative data and veterinary advice. These resources motivated change through influencing farmer decision making, which depended on the value they saw in the data as a decision-making tool. The economic or moral interest farmers expressed in their surplus calves also influenced whether farmers intended to implement management changes. Recommendations for future implementation of benchmarking include targeting producers who are motivated to improve and who value the future performance of their calves, have engaged calf care personnel, and those who prefer data-driven decision making. This study supports the impactful role veterinarians can play in motivating improved calf care practices through providing benchmarking services.

Impact of synbiotics on growth performance and gut health in Murrah buffalo calves.

Synbiotics have been used as biotherapeutic supplements for prevention of new-born calf gastrointestinal disorders. Present study was conducted to evaluate the impact of fructo-oligosaccharide, mannan-oligosaccharide and inulin along with Lactobacillus plantarum CRD-7 and Lactobacillus acidophilus NCDC15 on the nutrient digestibility, growth performance and faecal microbial population of pre-ruminant buffalo calves. Twenty-four Murrah calves (5 days old) were randomly assigned to four groups of six calves in each using randomized block design. Calves in Group I (control) received only a basic diet of milk, calf starter and berseem with no additives. Calves in Group II (SYN1) were fed 6g fructo-oligosaccharide (FOS) + Lactobacillus plantarum CRD-7 (100 ml). Calves in Group III (SYN2) were fed 9g inulin + L. plantarum CRD-7 (50 ml), while calves in Group IV (SYN3) received 4g MOS + L. acidophilus NCDC15 (200 ml) as fermented milk having 108 CFU/ml/calf/day in addition to the basal diet. The results revealed that digestibility of dry matter, crude protein, ether extract and average daily gain were all higher (P < 0.05) in SYN1 as compared to control group. The antioxidant enzyme activity, humoral and cell mediated immunity performed well in SYN1, SYN2 and SYN3 as compared to control. Diarrhoea and faecal scouring were lower (P < 0.05) in all supplemented groups than control. Faecal Lactobacilli and Bifidobacterium counts were also higher in SYN1 group followed by SYN2 and SYN3. Faecal ammonia, lactate, pH, and volatile fatty acids level were increased in SYN1 supplemented groups. The synbiotic combination of 6g FOS + L. plantarum CRD-7 had better response on digestibility, average daily gain, antioxidant enzymes, immune response, faecal microbiota and metabolites and also reduce the faecal score and diarrhoea incidence. Therefore, supplementation of 6g FOS + L. plantarum CRD-7 can be advised for general use in order to promote long-term animal production.

Invited review: Total solids concentration in milk or milk replacer for dairy calves

Restricting milk or milk replacer (MR) fed to dairy calves to 10% of body weight at 12.5% total solids (TS) concentration is a common feeding strategy that promotes early weaning and lowers total feed costs for raising young calves. However, this strategy has been associated with inferior performance and compromised welfare. Because a restricted liquid nutrition plan limits calf growth due to limited supply of nutrients, research on increased supply of nutrients from liquid has shown improved growth, health, and welfare of calves. Nutrient supply may be increased by feeding larger amounts of milk or MR averaging 12.5% TS, or by increasing TS above the usual 12.5% TS by increasing MR TS concentration alone (TS+), or by increasing TS concentration and volume simultaneously (TSV+). The objective of this review is to discuss liquid nutrition plans with greater TS concentration in MR or in milk diets, considering the effects of such strategies on performance and digestive tract development before weaning and the future performance of dairy calves. This review will focus on liquid nutrition plans that are based on increased TS concentration (i.e., TS+ or TSV+); therefore, enhanced liquid nutrition plans based only on increased volumes will not be the discussed. Improved growth rates have been observed in calves fed TSV+ programs. However, reduced starter intake preweaning can also have negative effects on dry matter intake, average daily gain, and digestibility postweaning. Feeding a TS+ program may reduce impairment of starter intake and therefore have positive effects on performance, nutrient digestibility, and health. When considering an accelerated nutrition plan with TS+ or TSV+, it is important to consider osmolality of the liquid diet. Further studies are necessary to confirm this hypothesis and the cost-benefit of alternative liquid nutrition plans, as well as the optimal TS concentration of milk or MR fed to dairy calves.

Effects of supplementing a direct-fed microbial containing Enterococcus faecium 669 on performance, health, and metabolic responses of preweaning Holstein dairy calves

This study aimed to evaluate the effects of Enterococcus faecium 669 supplementation on performance, health, parasitological, microbiological, and hematological responses of pre-weaning dairy calves. Forty-two newborn Holstein female calves [initial body weight (BW) 44 ± 4.5 kg] were used in the present study. At birth, calves were ranked by initial BW and assigned to 1 of 2 treatment groups: 1) whole milk (CON; n = 21) and 2) whole milk with the addition of E. faecium 669 (DFM; n = 21). During the entire experimental period (63 d), DFM was daily-fed at a rate of 2.5 × 109 colony forming units/head. All calves were offered a mixture of a starter feed and wheat straw for ad libitum consumption. Supplement intake was evaluated daily, whereas calves were weighed on a weekly basis from d 0 to weaning (d 63). Diarrhea was assessed once a day, whereas fecal and blood samples were collected for microbiological, parasitological, and hematological responses. All data were analyzed with SAS and using calf as the experimental unit. A treatment × week interaction was observed for BW, as DFM-supplemented calves were heavier than CON cohorts on d 56 (+ 4.7 kg) and at weaning on d 63 (+ 4.8 kg). A similar interaction was observed for ADG and dry matter intake (DMI), with greater ADG for DFM-supplemented calves from d 35 - 42, greater ADG and DMI from d 49 - 56, and greater DMI from d 56 - weaning. Moreover, diarrhea occurrence tended to be lower, whereas rectal temperature was 0.2°C lower for DFM supplemented calves. Treatment × day interactions were observed for the occurrence and counts of Eimeria spp., as DFM-supplemented calves tended to have a reduced number of positive observations on d 42 of the study vs. CON and a significant reduction in positive animals from d 21 to 42 was observed in DFM, but not in CON calves. For Cryptosporidium spp., no treatment effects were observed on overall occurrence (%), but DFM-supplemented calves had a greater count of oocyst per gram vs. CON. No treatment × day interaction or main treatment effects were observed for any of the blood variables analyzed herein, exception being monocytes concentration. In summary, pre-weaning E. faecium 669 supplementation improved performance, diarrhea occurrence, and reduced the number of calves positively-detected for Eimeria spp.

Drinking Warm Water Promotes Performance by Regulating Ruminal Microbial Composition and Serum Metabolites in Yak Calves.

Yaks live in the harsh environment of the Qinghai-Tibet Plateau, and the cold climate causes lower growth efficiency. The aim of this experiment was to explore the effects of drinking warm water on the growth performance in yak calves and investigate the underlying physiological mechanisms. A total of 24 Datong yak calves were selected and randomly assigned into the cold water group (group C, water temperature around 0-10 °C without any heating; 58.03 ± 3.111 kg) and the warm water group (group W, water constantly heated at 2 °C; 59.62 ± 2.771 kg). After the 60-day experiment, body weight was measured, and rumen fluid and blood serum samples were collected for analysis. The results show that the body weight and average daily gain of yaks that drank warm water were higher compared to those that drank cold water (p < 0.05). The acetic, propionic, isobutyric, valeric, and isovaleric acid concentrations were higher in group W than in group C (p < 0.05). Additionally, warm water changed the ruminal microbes at different levels. At the phylum level, the relative abundance of Tenericutes, Kiritimatiellaeota, and Elusimicrobiota was higher in group C (p < 0.05). At the genus level, three genera were increased by warm water, including Ruminococcoides and Eubacteriales Family XIII. Incertae Sedis, and 12 genera were decreased, including Ruminococcus (p < 0.05). At the species level, unclassified Prevotellaceae and Ruminococcoides bili were increased by warm water compared to cold water (p < 0.05). According to the metabolomics results, metabolites, including valine, isoleucine, PC (15:0/22:2(13Z,16Z)), and LysoPC (18:0/0:0), were increased in the warm water group compared to the cold water group (p < 0.05), and were enriched in glycerophospholipid and amino acid metabolism pathways. This study analyzed the differences in ruminal microbes and metabolomes of yak calves provided with water at different temperatures and revealed the potential mechanism for better performance promoted by warm drinking water.

Effects of dietary supplementation of selenium and moringa oleifera leaves on growth performance of pre-pubertal Kundhi buffalo bull calves

The Kundhi buffalo, a unique and robust breed of water buffalo (Bubalus bubalis), is native to the Sindh province in Pakistan. This breed is well-adapted to the local environment and known for its excellent milk production, meat quality, and draught power. There is a growing need to develop strategies that focus on the sustainable conservation and genetic improvement of this breed to preserve its valuable traits for future generations. Twelve young bull calves belonging to elite Kundhi buffaloes (observed phenotypically) were obtained from progressive farmers based on their parent's performance records. The bull calves, aged approximately 10-15 months, were initially weighed (rages from 150 to 200 kg) and randomly divided into three groups, namely C, S, and M, each group were comprising 04 animals. Group C was designated as the control group and fed basal diet only, while calves belonging to Group S were given a dietary supplement of Selenium Yeast Sel-Plex®, with a dosage of 0.3mg/kg dry matter and Group M was treated with Moringa olifera leaves (dried) at the rate of 100g/ animal. This experiment was conducted for 12 weeks. The results of present study indicated that significantly (P&lt;0.05) higher monthly body weight gains (14.05 kg/month) were recorded in Kundhi buffalo bull calves of S followed by the M (11.67 kg/month) in comparison to the C group (9.75kg/month) of the animals. The positive coefficient of correlation was seen between age and body weight in all tested subjects. In terms of the body conformation; the monthly developmental gains of the heart girth, body length, and height were observed significantly (P&lt; 0.05) higher (11.2, 8.89 and 8.94 cm) in S, followed by M (8.23, 4.89 and 6.39 cm) in comparison to the control bull calves (4.74, 3.58 and 3.27 cm), respectively. High levels of the testosterone (0.481 ng/ml) were determined in the bull calves of S, followed by M (0.33 ng/ml) in comparison to C (0.208 ng/ml) group. The monthly gains of the scrotal circumference were recorded significantly (P&lt;0.05) higher (1.65 cm) in the S, than to M (1.21 cm) and that of control (0.40 cm) group calves

Performances of Post-weaned Pasundan Calves Fed Extra Diets in an Extensive Grazing System

Changing from the pre-weaning to the post-weaning period is a transition from liquid to solid feed accompanied by a dramatic transformation of the GI tract. Supplemental solid feeding of grazing post-weaning calves is expected to improve their productivity. The study aimed to determine the effect of extra diet on the performances of post-weaned Pasundan calves (15 males and 15 females) that were grazed, using a completely randomized design of 2x3 factorials (two sex factors x three diet factors). The diet treatments were that post-weaned Pasundan calves were grazed: without being given extra diets (grazing/control), extra diets without urea-impregnated zeolite (extra diet-1), and extra diets with urea-impregnated zeolite (extra diet-2). The parameters were diet consumption (only for extra diets, unmeasured grazing consumption), body weights, and body condition. The data were analyzed with GLM Univariate. The results showed: The interaction between diet treatment and sex did not affect all the observed parameters. Consumption of extra diet-1 (529.37±3.06 g DM/head/day) was higher (P0.05) than extra diet-2 consumption (525.17±1.96 g DM/head/day), but after a correction of body weight, the result was no different.  Sex factors did not affect all observed parameters. The ADG of post-weaned calves fed extra diet-1 (155.8±27.5 g), or extra-2 diet (124.2±56.3 g) was higher (P0.05) than the grazing (66.67±35.8 g). The extra diet-1 produced a higher change in body condition (1.8±0.78, P0.05) than extra diet-2 or grazing (1.2±0.42). In conclusion, feeding extra diet-1 to post-weaned Pasundan calves increased ADG by 234% and improved the body condition by 150% better than calves that were only grazed in an extensive grazing system.

The Effects of Zinc Supplementation on Growth, Diarrhea, Antioxidant Capacity, and Immune Function in Holstein Dairy Calves.

The current study examined the effects of supplementary zinc proteinate (ZnPro) and zinc oxide (ZnO) on growth performance, diarrhea, antioxidant capacity, immune function, and mineral element concentrations of calves aged 1 to 28 days. A total of twenty-four newborn calves were divided randomly into 3 groups (n = 8; 2 males and 6 females per group), and each received: 0 mg/d Zn (CON), 627 mg/d ZnPro (80 mg/d Zn; ZnPro group), and 101 mg/d ZnO (80 mg/d Zn; ZnO group). The calves received the additive in their milk during the first 28 days of life. Compared with the CON group: ZnPro and ZnO improved average daily gain (ADG) and decreased the feed:gain ratio (FGR) between days 1 and 14 (p < 0.05), while the ADG increased and FGR decreased only in the ZnPro group between days 1 and 28 (p < 0.05). The incidence of diarrhea decreased (p < 0.05) in the ZnPro and ZnO groups between days 15 and 28 as well as days 1 and 28, but decreased (p < 0.05) only in the ZnPro group between days 1 and 14. The serum immunoglobulin G (IgG) concentration of the ZnPro and ZnO groups increased on days 14 and 28 (p < 0.05). ZnPro supplementation increased serum IgM concentration during the whole study, while ZnO enhanced serum IgM concentration only on day 14 (p < 0.05). In the ZnO group, the serum concentration of cytokines interleukin (IL)-10 increased on day 14, while that of IL-1β increased on day 28 (p < 0.05). In addition, ZnPro reduced the serum malondialdehyde (MDA) concentration on days 14 and 28 (p < 0.05). Both ZnPro and ZnO increased the serum concentrations of alkaline phosphatase (ALP) and metallothionein (MT) on day 14 (p < 0.05). With zinc supplementation, plasma Zn concentration increased (p < 0.05) on days 14 and 28 of age. We concluded that supplementary ZnPro and ZnO reduced incidences of diarrhea and promoted the immune function, but ZnPro improved the growth performance and antioxidant capacity of Holstein dairy calves to a greater extent.

Zinc methionine improves the lipid metabolism that is associated with the alteration of intestine mucosal proteomes and microbiota of newborn Holstein dairy calves

AbstractSupplementation of diets with a modest amount of zinc methionine (ZM) has been documented to improve the growth performance and antioxidant function of dairy calves, but the underlying mechanisms remain elusive. In the present study, 16 dairy calves were allocated to a control (CON) group (calves consumed a basal diet) and a ZM group (calves ingested the basal diet and had an additional 455 mg ZM/day, corresponding to 80 mg zinc/day). The calves were fed these diets for 2 weeks, after which their serum antioxidant parameters, lipids, and jejunal mucosal proteome and microbiota were analyzed. The ZM group had lower levels of total cholesterol, triglycerides, and malondialdehyde but higher high‐density lipoprotein cholesterol and glutathione peroxidase activity in the serum. A total of 142 differentially expressed proteins in the intestinal mucosa between the CON and ZM groups had been identified (ZM upregulated 117 proteins and downregulated 25 proteins). In addition, the protein expression of acyl‐coenzyme A oxidase 1, fatty acid binding protein 2, and peroxisome proliferator‐activated receptor gamma was higher in the ZM group. 16S rRNA gene sequencing indicated beneficial microbes, such as Veillonellaceae, Akkermansia_muciniphila, and Bifidobacterium adolescentis, which were more abundant, whereas Acinetobacter lwoffii was less abundant in calf jejunal mucosa in the ZM group. Finally, the propionate, butyrate, and iso‐valerate concentrations in the jejunal digesta were greater in the ZM group than those in the CON group. Collectively, the present study shows that ZM supplementation improves the serum and intestine mucosal lipid metabolism associated with the alterations in mucosal fatty acids β‐oxidation and microbiota.

Effects of weaning strategies on health, hematology, and productivity in Holstein dairy calves

Weaning strategies in dairy calves vary considerably, though the effect on animal health is unclear. This study examined the effects of calf weaning age (6 vs. 8 wk) and pace (abrupt vs. gradual) on performance, blood, and health parameters in dairy calves. The experiment consisted of a 2 × 2 factorial arrangement of treatments, where the factors included weaning age (early vs. late) and weaning pace (abrupt vs. gradual). Holstein calves (n = 72), blocked by sex and birth weight, were randomly assigned to one of 4 treatments (n = 18 per treatment): early-abrupt (EA), early-gradual (EG), late-abrupt (LA), and late-gradual (LG). Milk replacer (24% crude protein, 17% fat; up to 1,200 g/d) was fed twice daily; water, calf starter (18% crude protein), and chopped alfalfa hay were fed ad libitum. Daily intakes of milk replacer, calf starter, and forage were recorded from birth until end of weaning. Body weight, selected health measures, blood hematology, and fecal scores were obtained 1 d preweaning and 1 d postweaning. Calves were orally bolused with a rumen pH logger for the last 3 d of the weaning transition and rumen pH was measured continuously. Data were analyzed with age, pace, age × pace interaction, birthweight, and sex as fixed effects, and starting date as a random effect. Greater age at weaning increased respiration, whereas gradual-weaned calves had lower respiration rate. Heart rate was lower in gradual than in abrupt weaned groups. Fecal score had a marginal increase in late-weaned groups and significantly increased in gradually weaned groups. No difference was detected in body core temperature by age, pace, or interaction. During the weaning transition, average daily gain was lower in LA than EA and gradually weaned groups had an increased average daily gain. Change in grain intake, but not forage intake, was greater in gradually weaned groups. Mean rumen pH marginally increased from EG to LG and from LA to LG. No difference was detected among treatments in red or white blood cell counts, and hemoglobin. Procalcitonin was marginally highest in the LA group, while blood hematocrit increased in abruptly weaned groups. Overall, calf health is affected by both age and pace of weaning, though the health parameters affected by age and pace differ.

Association between transfer of passive immunity, health, and performance of female dairy calves from birth to weaning

The objective of this observational study was to compare calf health, average daily weight gain, and calf mortality considering the proposed categories of transfer of passive immunity (TPI) by the consensus report of Lombard et al. (2020). The consensus report defines 4 categories of passive immunity (excellent, good, fair, and poor) of calves obtained after colostrum ingestion. The association between the 4 TPI categories was analyzed on calf health (i.e., hazards for morbidity and mortality), and average daily weight gain (ADG) of female Holstein Friesian calves during the first 90 d of age. A further aim of this study was to examine the effects of calving-related factors, such as dystocia or winter season, on TPI status. We hypothesized that calves with excellent TPI have greater ADG, lower risks for infectious diseases such as neonatal diarrhea, pneumonia, and omphalitis, and lower mortality rates. This observational study was conducted from December 2017 to March 2021. Blood was collected from 3,434 female Holstein Friesian dairy calves from 1 commercial dairy farm. All female calves aged 2 to 7 d were assessed for TPI status by determination of total solids (TS) in serum via Brix refractometry by the farm personnel once a week. Passive immunity was categorized according to Lombard et al. (2020) with excellent (≥9.4% Brix), good (8.9-9.3% Brix), fair (8.1-8.8% Brix), or poor TPI (<8.1% Brix). For the analysis of ADG and calving ease 492 or 35 calves had to be excluded due to missing data. The distribution of calves according to TPI categories was as follows: 4.8% poor (n = 166), 29.5% fair (n = 1,012), 28.3% good (n = 971), and 37.4% excellent (n = 1,285). From the calving-related factors, parity of the dam, calving ease, birth month, calving assistance by different farm personnel, and day of life for TPI assessment were significantly associated with TS concentration. Out of 3,434 calves, 216 (6.3%) had diarrhea, and 31 (0.9%) and 957 (27.9%) suffered from omphalitis and pneumonia during the first 90 d of life, respectively. Overall, the morbidity during the preweaning period was 32.6% (n = 1,118), and the mortality was 3.1% (n = 107). The ADG was 0.90 ± 0.15 kg with a range of 0.32 to 1.52 kg. The Cox regression model showed that calves suffering from poor TPI tended toward a greater hazard risk (HR) for diarrhea (HR = 1.57, 95% CI: 0.92-2.69) compared with calves with excellent TPI. Calves suffering from TPI had a greater HR for pneumonia (HR = 2.00, CI: 1.53-2-61), overall morbidity (HR = 1.99, CI: 1.56-2.55), and mortality (HR = 2.47, CI: 1.25-4.86) in contrast to excellent TPI. Furthermore, calves with good and fair TPI had significantly greater HR for pneumonia (good TPI: HR = 1.35, CI: 1.15-1.59; fair TPI: HR = 1.41, CI: 1.20-1.65) and overall morbidity (good TPI: HR = 1.26, CI: 1.09-1.47; fair TPI: HR = 1.32, CI: 1.14-1.53) compared with the excellent TPI category. Average daily weight gain during the first 60 d of life was associated with TPI categories. Calves with excellent and good TPI status had ADG of 0.90 ± 0.01 kg/d and 0.92 ± 0.01 kg/d (mean ± SE), respectively. The ADG of calves with fair TPI status was 0.89 ± 0.01 kg/d, and calves suffering from poor TPI had 0.86 ± 0.01 kg/d. Average daily weight gain differed in calves with poor TPI compared with the other categories. Fair and excellent TPI differed additionally from good TPI. We found no statistical difference between the TPI categories fair and excellent. In conclusion, poor TPI was associated with higher morbidity and mortality during the first 90 d of life. Furthermore, calves with fair, good or excellent TPI had greater ADG.

The age at first consumption of forage in calves and its effect on growth and rumination in the short- and long-term

BackgroundPrevious investigations into the effect of dietary forage on calf performance have been inconsistent, and there is a paucity of information exploring the effect of age on the growth performance and rumination of calves. Eighty-four female Holstein calves (41.5 ± 4.2 kg) were enrolled at birth, a subset of the calves were fed calf starter only (CON, n = 21) while the rest (n = 63) were classified into three treatment groups: the early (EHAY, n = 26, 5.1 ± 0.8 d), the middle (MHAY, n = 21, 7.9 ± 0.8 d) and the late (LHAY, n = 16, 12.1 ± 1.4 d) hay consumers. The short-term effect of the age at first forage consumption (AFF) on calves’ feed intake was monitored until d 84. In addition, the long-term effects of AFF on body weight, structural growth and rumination behavior were recorded until d 196. Rumen samples were collected on d 1, 7, 35, 84 and 196 to analyze the rumen fermentation, while fecal samples were collected from d 78 to 84 to estimate digestibility parameters.ResultsTreatment had no effect on feed intake. While, the EHAY calves tended to have lower BW and ADG compared to LHAY and CON calves. Several total-tract apparent digestibility parameters and digestible nutrients intake were significantly lower in EHAY calves compared with CON and LHAY calves. Calves in the EHAY group tended to begin ruminating ealier, while CON calves were the latest (12.3 vs. 15.5 days of age). A treatment and time interaction was present for rumination time due to greater rumination in calves consuming hay compared to CON calves in week 10 to 12, the differences in rumination disappeared afterwards, no long-lasting significant differences in the rumination and rumen fermentation parameters were found between treatments.ConclusionsIn conclusion, this study showed that hay consumption earlier in life (in the first week, around 5 days of life) could negatively affect the growth of the calf in the short and long term. Compared to consuming hay from the second week (around 12 days of life) or feeding concentrate only without hay, starting to consume hay from the first week could compromise nutrient digestibility and digestible nutrient intake independent of developing rumination behaviour and rumen fermentation.