Carla Bittar
@esalq.usp.br
Associate professor
Luiz de Queiroz College of Agriculture
RESEARCH, TEACHING, or OTHER INTERESTS
Animal Science and Zoology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Ana Paula Silva, Amanda M. Cezar, Ariany F. de Toledo, Marina G. Coelho, Cristiane R. Tomaluski, Gercino F. Virgínio Júnior, and Carla M. M. Bittar
Springer Science and Business Media LLC
AbstractFifty Holstein calves were allocated in randomized blocks and distributed in a 2 × 2 factorial arrangement; (A) two sources of Ig: (1) Control: bovine colostrum (25% Brix); (2) Enriched colostrum: mid-quality bovine colostrum (20% Brix) enriched with colostrum replacer to 25% Brix; and (B) two transition feeding diets: (1) Whole milk (WM): supply of 4 L/day of whole milk for 3 days after the colostrum feeding; and (2) Formulated transition milk (FTM): supply 4 L/day of whole milk enriched with 70 g/L of colostrum replacer for 3 days after the colostrum feeding. Blood samples were collected at 0, 24, 48, and 72 h of age to determine total serum protein (TSP), glucose, non-esterified fatty acids (NEFA), erythrocyte and leukocyte concentrations. IgG was measured at 48 h. During the preweaning period, calves received 6 L/day of whole milk. Blood samples were collected weekly to determine TSP, glucose, and lactate. The colostrum protocols were equally efficient for transfer of passive immunity with IgG concentration at 48 h ≥ 49.6 g/L. Colostrum or transition feeding program did not influence the erythrocyte and leukocyte concentrations. The TSP concentration measured until 72 h was higher for calves fed maternal colostrum. Calves fed milk in the transition period had higher glucose concentrations. Calves receiving bovine colostrum and FTM had higher glucose concentrations in the preweaning period, while the enriched colostrum decreased plasma lactate concentrations. In summary, enrichment of mid-quality colostrum is an alternative in situations of a shortage of high-quality colostrum; however, feeding 4 L/day of FTM only for 3 days after colostrum feeding does not show additional benefits.
A.F. Toledo, J.G. Dantas, R.D.F. Barboza, C.R. Tomaluski, I.C.R. Oliveira, N.I. Carvalho, E.D. Marino, D.M. Polizel, E.K. Miller-Cushon, and C.M.M. Bittar
American Dairy Science Association
The objective of this study was to evaluate effects of forage inclusion and sources on performance, metabolism, and feeding behavior of dairy calves. Forty-eight Holstein calves were blocked and randomly assigned to 1 of 4 dietary treatments according to sex, and body weight (BW) at 28 d of life to determine the effects of feeding forage sources (ensiled and dry), with different quality on performance, metabolites, and behavior. Treatments consisted of a no-forage coarsely ground starter (CON); or total mixed ration containing 7.5% on DM basis of Tifton hay of either medium quality (MH) or low quality (LH); or 10% on DM basis of corn silage (CS). During the first 28 d of life, all calves received 3 L of whole milk twice daily, a commercial pelleted starter and no forage, and water ad libitum. After that, the solid diet was changed to the respective dietary treatments. Calves were gradually weaned from 52 to 56 d of age, and followed for 14 d post-weaning. Individual solid feed and milk intakes were recorded daily, and BW and metabolic indicators of intermediate metabolism were recorded weekly. Behavior was recorded, and the analysis was conducted on wk 7 (preweaning) and 10 (post-weaning). Solid feed intake increased at wk 7 and 8 when MH, LH, and CS were included in TMR; the same results were observed post-weaning. The diets did not affect the average daily gain and body weight, but the feed efficiency increased with the CON diet. The β-hydroxybutyrate concentration was greater in calves receiving TMR containing forage than CON diet. Furthermore, calves supplemented with forage had a greater rumination time. In conclusion, all forage sources included in the TMR showed feed intake and behavior benefits, reinforcing the need for fiber from forage in pre- and post-weaning diets.
Gercino Ferreira Virgínio Júnior, Cécile Anna Jeanne Duranton, Marilia Ribeiro de Paula, and Carla Maris Machado Bittar
Asian Australasian Association of Animal Production Societies
Objective: This study aimed to evaluate the effect of feeding milk replacer (MR) with varying levels of lactose and the increased supply of total solids (from 750 to 960 g/d) on performance, blood metabolites, and health of Holstein male calves during the preweaning period.Methods: Forty newborn Holstein calves (10 per treatment) were blocked according to birth weight and date of birth and distributed in a randomized block design to different liquid diets: Whole milk powder (WMP) diluted to 125 g/L solids; MR with 48% lactose (48L), diluted to 125 g/L solids; MR with 53% lactose (53L), diluted to 125 g/L solids; 53L MR corrected to 160 g/L solids (16TS) by the inclusion of a solid corrector. Calves were individually housed in wood hutches, fed 6 L/d of the liquid diet, and had free water and starter concentrate access. The study lasted 56 days.Results: Liquid diet intake was higher for calves fed 16TS than for other treatments. Calves fed 16TS presented higher protein and fat intake, followed by those fed WMP and the 48L or 53L MRs. Lactose intake was higher for 16TS-fed calves, followed by 53L, 48L, and WMP-fed calves. Starter and total dry matter intake did not differ among liquid diets. The average daily gain was higher for 16TS than 48L-fed calves, with the other treatments being intermediary. The lowest feed efficiency was observed for calves fed 48L. No effects on health were observed, as well as on selected blood metabolites, except for albumin concentration, which was higher for calves fed 16TS and WMP.Conclusion: Higher total solids content (160 g/L) in MR increases nutrient intake and consequently improves the performance of dairy calves. Feeding MRs with levels of lactose up to 53% of the DM had no deleterious effect on the performance or health of the calves.
Allison Queiroz de Oliveira, Milaine Poczynek, Carla Maris Machado Bittar, and César Gonçalves de Lima
Revista Brasileira de Biometria
Some experimental studies are carried out considering a longitudinal feature. In view of this, the classical regression models are not able to handle with it, since the independence assumption between the observations is violated. To handle with this kind of data it was proposed the called linear mixed-effects models, where it is possible to model the response variable taking into account the correlation between the observations, and even between the response variables, when there are two or more of them in study, setting a bivariate or multivariate scenario, respectively. For the diagnosis of the linear mixed-effects models the least confounded residuals are quite recommended due to their lower bias in relation to other types of residuals, but it is not so used in the literature. Using a data set of dairy calves’ performance according to three different diets over eight weeks, the linear mixed-effects models theory under univariate and bivariate approach was applied alongside the least confounded residuals in the diagnosis of the model for both approaches. Comparing the univariate and bivariate approaches, the last one was more informative presenting lower standard errors’ values for its estimates, while the least confounded residuals was more efficient than the classical residuals present in the literature.
Miguel Machado, Robson Mateus Freitas Silveira, Carla Maris Machado Bittar, Cristian Marcelo Villegas Lobos, and Iran José Oliveira da Silva
Malque Publishing
This study aimed to determine the associations between ear and tail position and stroking or umbrella stimuli in dairy calves at different stimulus application times (before the test, pretest, test, and posttest). Thirty-two mixedbred Holstein calves of different ages were subjected to stroking and an umbrella stimulus. For the stroking stimulation, a researcher stroked for 1 minute in the neck region with continuous and frequent movements (approximately 40 to 60 movements per minute) to simulate the speed with which an animal would receive allogrooming. For the umbrella stimulus, a researcher positioned himself one meter in front of the calf, with an umbrella in his hand, without making eye contact. Then, the umbrella was suddenly opened and remained open for one minute. The procedure was divided into six experimental attempts. The ear and tail positions were investigated. There was a significant effect of treatment on the ear and tail position variables. The "backward” ear posture and "arched" tail posture appear to be associated with the display of the stroking stimulus, while the "horizontal" ear and "between hind limbs" tail positions are associated with the umbrella stimulus. The data suggest that ear and tail positions are indicators of stroking or umbrella stimuli in dairy calves. There is great potential for using these methods to measure the emotional state of calves, and they can also be used as a tool to assess their welfare.
Marina G. Coelho, Ana Paula da Silva, Ariany F. de Toledo, Amanda M. Cezar, Cristiane R. Tomaluski, Rayane D. F. Barboza, Gercino F. Virginio Júnior, Ricardo P. Manzano, and Carla M. M. Bittar
Public Library of Science (PLoS)
Supplementation of dairy calves with essential oils in the liquid diet can reduce the incidence and severity of infectious diseases and promote better performance. Our objective was to evaluate an essential oil blend containing peppermint, eucalyptus, and menthol crystals and its effect on performance and health during the pre and postweaning period of dairy calves. At birth, 40 dairy calves (34 males and 6 females) were blocked according to sex and birth weight, randomly assigned to one of two treatments–commercial milk replacer diluted at 14% (MR) and the same liquid diet plus essential oil blend (MREO) at a dose of 4 mL per calf per day, divided into two meals during the first 28 days of life. Calves were individually housed and fed 6 L/d of the liquid diet, divided into two meals, and received starter concentrate and water ad libitum. Weaning was gradually reduced by 1L per day at d 51 until complete weaning at 56 days. After weaning, calves were evaluated until 70 days of age, when the experimental period ended. Intake, fecal, and health scores were evaluated daily, weight and body measures were recorded weekly, and blood parameters were evaluated at weeks 1, 2, 3, 4, and 8. Calves fed MREO tended to have higher total dry matter intake during the preweaning period. Furthermore, MREO calves had lower health scores and fewer days with a health score ≥ 4 (suggestive of bronchopneumonia), tended to lower coughing days and fewer veterinary interventions preweaning, and tended to lower health scores postweaning. The supplementation with a blend of essential oils containing peppermint, eucalyptus, and menthol crystals can reduce respiratory problems. Further studies are needed to investigate the dose and the supplementation period.
A.F. Toledo, S.C. Dondé, A.P. Silva, A.M. Cezar, M.G. Coelho, C.R. Tomaluski, G.F. Virgínio, J.H.C. Costa, and C.M.M. Bittar
American Dairy Science Association
Assuming that acetic acid plays a minor role in the development of ruminal epithelium of preweaning dairy calves, the fiber supply for growing calves has been neglected. More research has been done on including starch and nonfibrous carbohydrates in solid feed for preweaning calves. Accordingly, the fiber requirement of these calves is not well known, as diet recommendations vary greatly. Hence, elucidating the effects of including fiber from long particle sizes in the diet may be essential for helping calves overcome the transition challenge during weaning. Forty-five Holstein calves were used in a randomized block design, considering sex, birth date, and weight at 28 d of age, when the supply of the total mixed ration (TMR) with the inclusion of corn silage started. Three TMR with increasing whole-plant flint corn silage content (0, 10, or 20% on a dry matter basis) were compared: 0CS, 10CS, or 20CS, respectively. During the first 28 d of life, the calves were managed homogeneously and were fed 6 L/d of whole milk, a commercial calf starter pelleted, and water ad libitum. Next, the solid diet was changed to the respective solid feed treatment. Calves were gradually weaned from 52 to 56 d of age but were evaluated for an additional 14 d postweaning. Feed intake was measured daily, while body weight and metabolic indicators of intermediate metabolism were evaluated weekly. Ruminal fluid was collected at 6, 8, and 10 wk of age. Behavioral analysis was conducted on wk 7 (preweaning) and 10 (postweaning). There was a quadratic effect for dry matter intake from wk 7 to 10, with higher intake for the 10CS diet than the 0CS and 20CS diets. Consequently, the 10CS diet also promoted greater average daily gain at wk 8 and 9 compared with the 0CS and 20CS diets. However, the final body weight was not affected by the different solid diets. Silage inclusion in calves' diet positively affected time spent ruminating and chewing pre- and postweaning. Including 10% of whole-plant flint corn silage in the diets of young dairy calves is a strategy to increase total solid intake and decrease acidosis risk by increasing pH and ruminating activity around weaning.
Ana Paula da Silva, Amanda M. Cezar, Ariany F. Toledo, Sophia C. Dondé, Marina G. Coelho, Cristiane R. Tomaluski, Gercino F. Virgínio Júnior, and Carla M. M. Bittar
MDPI AG
The study aimed to evaluate the effect of maternal or formulated transition milk with colostrum powder on the performance and health of dairy calves. After receiving 12% of their birth weight in high-quality colostrum, 36 Holstein calves (17 males and 19 females) were blocked according to sex, birth date and birth weight (29.16 kg ± 1.34) and randomly distributed into three treatments: (1) Milk: supplying 4 L/d of whole milk (WM) for three days (n = 12); (2) Transition milk (TM): supplying 4 L/d of maternal transition milk for three days (n = 12); (3) Formulated transition milk (FTM): supplying 4 L/d of whole milk enriched with 280 g/d of colostrum powder, for three days (n = 12). Daily feeding was split into two feedings, and after the sixth feeding of the transition diet calves were fed 6 L/d of whole milk and had ad libitum access to water and calf starter until 56 d, when the study ended. Calves fed TM or FTM presented a higher total solids intake (p < 0.05). Concentrations of glucose (p = 0.096) and lactate (p = 0.063), evaluated from 0 h to 72 h, tended to be higher in WM-fed calves compared to TM. There were no effects on calf’s health or performance and weight; at the week 8 averaged 65.06 kg ± 1.85. All treatments resulted in adequate performance and good health, however, the potential benefits of providing TM or FTM were not seen in this study. The transition milk composition and the number of meals after colostrum feeding need more investigation.
Miguel Machado, Robson Mateus Freitas Silveira, Carla Maris Machado Bittar, Cristian Marcelo Villegas Lobos, and Iran José Oliveira da Silva
Elsevier BV
Marina Gavanski Coelho, Gercino Ferreira Virgínio Júnior, Cristiane Regina Tomaluski, Ariany Faria de Toledo, Maria Eduarda Reis, Sophia Cattleya Dondé, Lucas William Mendes, Luiz Lehmann Coutinho, and Carla Maris Machado Bittar
Scientific Reports Springer Science and Business Media LLC
AbstractThe liquid diet composition can affect dairy calves' performance and diarrhea incidence. The effect of three liquid diets on performance, incidence of diarrhea, and microbial community during diarrhea occurrence in dairy calves were evaluated. At birth, 35 dairy calves (20 male and 15 female) were randomly assigned to one of three treatments—refrigerated whole milk (WM), acidified whole milk (AWM), and milk replacer (MR). Intake, fecal score, and rectal temperature were evaluated daily, and performance and blood parameters were evaluated weekly during the preweaning period. Fecal samples from diarrheic calves were collected, and one initial and one final sample for each episode were selected. The bacterial community was assessed by sequencing the V3-V4 region of the 16S rRNA gene on the Illumina MiSeq platform and analyzed using the DADA2 pipeline. Calves fed WM had higher body weight at weaning, average daily gain, body measurements, and concentration of blood metabolites. The AWM-fed calves had a lower rectal temperature and fever days. Moreover, the MR-fed calves had lower beta-hydroxybutyrate concentration and a higher incidence of diarrhea. The fecal bacterial community of diarrheic calves showed dissimilarity among the AWM and the other treatments. At the compositional level, we observed a higher abundance of Fusobacterium and Ruminococcus genera (AWM), Prevotella (WM), and Lactobacillus (MR). In the AWM and MR diarrheic calves' feces, we also observed some beneficial bacterial genera. The performance and incidence of diarrhea of dairy calves were influenced by the liquid diet consumed and the bacterial composition of diarrhea.
M.E. Reis, M. Cantor, C.M.M. Bittar, and J.H.C. Costa
American Dairy Science Association
Poor vigor at birth has been associated with reduced IgG absorption from colostrum and a reduced vitality in neonatal dairy calves. Some natural compounds, such as green tea extract, may improve vitality in compromised calves. The objective of this randomized controlled trial was to evaluate the potential of supplementing a green tea extract (15 mL) to calves to improve vigor and activity behavior for the first 72 h postnatal. Also, this study aimed to investigate the influence of green tea extract supplementation on calf serum IgG concentration and the apparent efficiency of absorption (AEA) of colostral IgG. Holstein calves (n = 24) weighing 42.49 ± 1.07 kg postnatal received a complete random assignment at 3 h of one 15-mL dose of green tea extract (Calf Perk, TechMix) or distilled water orally before tube feeding colostrum replacer (Premolac Plus IgG, Zinpro) at 4 h postnatal. Two observers assessed for calving time and dystocia by live video stream to retrieve all calves within 2 h postnatal. One veterinarian performed a baseline vigor assessment based on heart rate and response to stimuli on all calves at 2.5 h, before colostrum feeding at 3.75 h, as well as at 24, 48, and 72 h postnatal. Calf blood samples were taken to assess total IgG by radial immunodiffusion assay at 2.5, 6, 12, 24, 48, and 72 h. Calf vitality was also observed continuously by video for all calves to determine whether treatment was associated with attempts to stand, lying time, and exploration of their pen environment for the first 24 h. We used an ordinal logistic model to evaluate the odds of green tea extract improving a calf's vigor category from 2.5 h postnatal to 72 h of age. Vigor score was categorized as abnormal (≤4), average (5), or alert (≥6), with hour as a fixed effect. We also ran mixed linear models to evaluate the effect of extract on total IgG and AEA, with time and dystocia as fixed effects. Five dystocia calves were enrolled (2 control, 3 extract), but assistance was minor (e.g., manual assistance and all were assisted within 1 h). Baseline vigor scores and baseline total IgG were not different between groups. Vigor score category was not associated with green tea extract supplementation (odds ratio 1.17; 95% CI: 0.43-3.15) but increased with time compared with controls. We observed no association of treatment with total IgG or AEA in the calves, suggesting green tea extract does not compromise IgG absorption. Calf vitality, lying behavior, and exploratory behavior were not associated with green tea extract treatment. Our findings suggest that green tea extract supplementation does not affect AEA and serum IgG concentration in calves. Future research should evaluate whether green tea extract improves vitality in calves experiencing severe dystocia.
Amanda Moelemberg Cezar, Sophia Cattleya Dondé, Cristiane Regina Tomaluski, Ana Paula da Silva, Ariany Faria de Toledo, Marina Gavanski Coelho, Gercino Ferreira Virgínio Júnior, and Carla Maris Machado Bittar
MDPI AG
The aim of this study was to evaluate the age and post-prandial variations in selected metabolite concentration that may indicate a shift in metabolism, from pre- to functional ruminant, according to the liquid diet fed to dairy calves. Sixteen newborn Holstein calves were included in the study in a randomized complete block experimental design. The calves were individually housed and fed 6 L/d with whole milk (WM) or milk replacer (MR). Blood samples were collected weekly at 0 h (before feeding), 1 h, 2 h, 4 h, and 8 h after morning feeding to evaluate glucose, β-hydroxybutyrate (BHB), fructosamine, total protein, and albumin. Calves fed WM had higher performance (p < 0.01) than did calves fed MR. The different liquid diets did not affect the average concentrations of plasma glucose. However, BHB was higher for WM-fed calves (p < 0.01). The concentration of plasma glucose reached the highest concentration at 1 and 4 hours after feeding WM or MR, respectively. Thus, these would be the most appropriate sampling times to study the glycemic status of calves according to the liquid diet fed. Fructosamine did not prove to be an informative metabolite to understand the shift in metabolism, as a function of rumen development, due to a small reduction as a function of age and a sampling time effect.
Marcos Donizete da Silva, Ana Paula da Silva, Marina Gavanski Coelho, Milaine Poczynek, Ariany Faria de Toledo, Gercino Ferreira Virgínio Junior, João Henrique Cardoso Costa, and Carla Maris Machado Bittar
Springer Science and Business Media LLC
M.E. Reis, A.F. de Toledo, A.P. da Silva, M. Poczynek, M.C. Cantor, G.F. Virgínío Júnior, L. Greco, and C.M.M. Bittar
American Dairy Science Association
Studies have shown that β-glucans extracted from the cell wall of cereals, algae, and yeasts have been associated with improved immune function. However, it is unknown whether algae β-glucan supplementation affects the performance, blood metabolites, or cell counts of immune cells in dairy calves. The objective of this randomized clinical trial was to evaluate whether supplementation of β-glucans to milk replacer in dairy calves fed 6 L/d improved growth performance and fecal status and altered the blood metabolite profile. In this trial, we enrolled Holstein calves (n = 34) at birth (body weight 36.38 ± 1.33 kg; mean ± standard deviation) to receive, from 1 d of age, either 2 g/d algae β-glucans mixed into 6 L/d of milk replacer [22.4% crude protein and 16.2% fat] or an unsupplemented milk replacer (control). The calves were blocked in pairs according to birth weight, sex, and date of birth (up to 5 d difference). Calves were housed individually, and calf starter (24.7% crude protein and 13.9% neutral detergent fiber) was offered ad libitum based on orts of the previous day until 56 d of age (end of the trial). Body weight was measured weekly, and health checks and daily fecal consistency were evaluated daily in every calf by the same observer. Calves with 2 consecutive days of loose feces that sifted through bedding were considered diarrhea positive. We used a linear mixed effects model to evaluate the effects of β-glucan supplementation fed during the preweaning period on performance (average daily gain), final weight, feed efficiency (FE), white blood cell count, and selected blood metabolites, repeated by time. A generalized linear mixed effects model was also run to evaluate the likelihood of a diarrhea bout in the first 28 d of life, controlling for the calf as the subject with a logistic distribution. We included age, serum total protein at 48 h, and birth weight as covariates. At 56 d, β-glucan-supplemented calves weighed more than control calves (56.3 vs. 51.5 kg). Treatment had no effect on total starter intake, but there was a treatment by age interaction for FE, with greater FE for β-glucan-supplemented calves in wk 3 and 5 of age. There was only a tendency for average daily gain to be greater in supplemented calves than in control calves for the duration of the study. Furthermore, control calves had 14.66 [95% confidence interval (95% CI): 9.87-21.77] times greater odds of having a diarrheal bout than β-glucan-supplemented calves. Control calves had 12.70 (95% CI: 8.82-18.28) times greater odds of having an additional day with an abnormal fecal score compared with β-glucan-supplemented calves, suggesting that supplementation ameliorated diarrhea severity. We found no association of treatment with concentrations of serum total protein, albumin, creatinine, or glucose during the preweaning period. Our findings suggest that dietary supplementation of 2 g/d of algae β-glucans to milk replacer improved fecal status and may affect growth, as evidenced by a higher weaning weight, compared with control calves. Future studies should explore the effect of algae β-glucans on lower-gut physiology and digestibility in dairy calves.
Cristiane Regina Tomaluski, Marina Gavanski Coelho, Ariany Faria de Toledo, Gercino Ferreira Virgínio Júnior, Ana Paula da Silva, Sophia Cattleya Dondé, and Carla Maris Machado Bittar
Livestock Science Elsevier BV
Marcos Busanello, Debora G. Sousa, Milaine Poczynek, Rodrigo de Almeida, Carla M.M. Bittar, Filipe A.C. Mendonça, and Dante P.D. Lanna
Journal of Dairy Science American Dairy Science Association
Few studies have been published on the body growth of replacement dairy heifers from Jersey (JER) and Holstein × Gyr (H × G) breeds, as most of them have focused on Holstein (HOL) heifers. In addition, HOL genetics vary significantly across countries. Our goal was to study the body growth curves of 3 distinct genetic groups of heifers (HOL, H × G, and JER) using data from Brazilian commercial dairy herds. Heart girth [to estimate body weight (BW)], hip height (HH), and withers height (WH) were measured. Weights (heifers and cows) and heights (only heifers) were collected from animals in several herds for each genetic group to model and describe the growth rates, mature body weight (MBW), weights, and heights for the recommended age at first breeding (RAFB) and first calving (RAFC). The RAFB values for HOL, H × G, and JER cattle were 15, 18, and 13 mo, respectively. The RAFC values for HOL, H × G, and JER cattle were 24, 27, and 22 mo, respectively. Data were obtained from 18 dairy farms located in 4 Brazilian states and analyzed using nonlinear modeling. Data were collected from 2,266 animals: 878 HOL, 610 H × G, and 778 JER cattle. We observed different body growth patterns in each genetic group. Jersey cattle matured earlier than HOL and H × G, especially for BW and HH. Mature BW of the HOL, H × G, and JER cattle was 681, 607, and 440 kg, respectively. All genetic groups reached the recommended BW at RAFB. However, the genetic groups did not reach the recommended BW at RAFC. Average daily weight gain from weaning to RAFB was 0.84, 0.53, and 0.54 kg/d for HOL, H × G, and JER cattle, respectively. Average daily gain from RAFB to RAFC was 0.53, 0.42, and 0.48 kg/d for HOL, H × G, and JER cattle, respectively. The HH at RAFB and RAFC were 130 and 139 cm for HOL, 130 and 137 cm for H × G, and 114 and 124 cm for JER. Withers height at RAFB and RAFC were 125 and 134 cm, 125 and 134 cm, and 110 and 121 cm for HOL, H × G, and JER cattle, respectively. In general, the rearing practices were adequate to reach the recommended BW at RAFB but below the recommended BW at RAFC for all genetic groups. In addition, each genetic group demonstrated different body growth patterns, especially for BW.
B.D. Dauria, A. Sigdel, J. Petrini, P.P. Bóscollo, F. Pilonetto, M. Salvian, F.M. Rezende, V.B. Pedrosa, C.M.M. Bittar, P.F. Machado,et al.
Journal of Dairy Science American Dairy Science Association
The present study aimed to estimate covariance components of milk fatty acids (FA) and to compare the genomic estimated breeding values under general and heat-stress effects. Data consisted of 38,762 test-day records from 6,344 Holstein cows obtained from May 2012 through January 2018 on 4 dairy herds from Brazil. Single-trait repeatability test-day models with random regressions as a function of temperature-humidity index values were used for genetic analyses. The models included contemporary groups, parity order (1-6), and days in milk classes as fixed effects, and general and thermotolerance additive genetic and permanent environmental as random effects. Notably, differences in heritability estimates between environments (general and heat stress) increased (0.03 to 0.06) for unsaturated FA traits, such as unsaturated, monounsaturated, and polyunsaturated, at higher heat-stress levels. In contrast, heritability estimated between environments for saturated FA traits, including saturated FA, palmitic acid (C16:0), and stearic acid (C18:0) did not observe significant differences between environments. In addition, our study revealed negative genetic correlations between general and heat-stress additive genetic effects (antagonistic effect) for the saturated FA, C16:0, C18:0, and C18:1, which ranged from -0.007 to -0.32. Spearman's ranking correlation between genomic estimated breeding values ranged from -0.27 to 0.99. Results indicated a moderate to strong interaction of genotype by the environment for most FA traits comparing a heat-stress environment with thermoneutral conditions. Our findings point out novel opportunities to explore the use of FA milk profile and heat-stress models.
S. Dondé, A. Cezar, A. de Toledo, M. Coelho, C. Tomaluski, M.E. Reis, A.P. Silva, M. Silva, G. Virgínio Jr, and C.M. Bittar
The Kielanowski Institute of Animal Physiology and Nutrition, PAS
. Thirty-six newborn Holstein calves were used in a
Gercino Ferreira Virgínio Júnior and Carla Maris Machado Bittar
Animal Health Research Reviews Cambridge University Press (CUP)
Abstract This review aims to explain how microbial colonization of the gastrointestinal tract (GIT) in young dairy calves is related to health and, consequently, to the performance of these animals. The review addresses everything from the fundamental aspects of microbial colonization to the current understanding about the microbiota manipulation to improve performance in adult animals. The ruminal microbiota is the most studied, mainly due to the high interest in the fermentative aspects, the production of short-chain fatty acids, and microbial proteins, and its effects on animal production. However, in recent years, the intestinal microbiota has gained space between studies, mainly due to the relationship to the host health and how it affects performance. Understanding how the GIT's microbiota looks like and how it is colonized may allow future studies to predict the best timing for dietary interventions as a way to manipulate it and, consequently, improve the health and performance of young ruminants.
Marcos Busanello, Debora Gomes de Sousa, Filipe Araújo Canedo Mendonça, Veridiana Lourenço Daley, Rodrigo de Almeida, Carla Maris Machado Bittar, and Dante Pazzanese Duarte Lanna
Animals MDPI AG
Several models for predicting dry matter intake (DMI) of replacement dairy heifers have been developed; however, only a few have been evaluated using data from heifers of different breeds raised under tropical conditions. Thus, the objective of this study was to evaluate the DMI equations for dairy heifers managed under tropical conditions. A total of 230 treatment means from 61 studies using dairy heifers (n = 1513 heifers, average body weight = 246 kg) were used. The animals were grouped into two groups based on their genetics: (1) Bos taurus (Holstein, Jersey, Brown Swiss, and Holstein × Jersey) and (2) crossbred (Bos taurus × Bos indicus). Seven previously published DMI equations (HH, HHJ, QUI, STA, 2001 NRC, OFLin, and OFNLin) for heifers were evaluated using mean bias, slope bias, mean squared prediction errors (MSPE) and its decomposition, and other model evaluation statistics. For Bos taurus heifers, our results indicated that OFNLin and HHJ had lower mean bias (0.13 and 0.16 kg/d, respectively) than other models. There was no significant slope or mean bias for HHJ and OFNLin (p > 0.05), indicating agreement between the observed and predicted DMI values. All other models had a significant mean bias (p < 0.05), whereas the QUI model also presented a significant slope bias (p < 0.02). For crossbred heifers, the STA equation was the only one that did not present mean and slope bias significance (p > 0.05). All other DMI models had significant mean bias when evaluated using crossbred data (p < 0.04), and QUI, OFLin, and OFNLin also presented significant slope bias (p < 0.01). Based on our results, predictions from OFNLin and HHJ best represented the observed DMI of Bos taurus heifers (MSPE ≤ 1.25 kg2/d2, mean bias ≤ 0.16 kg/d), whereas STA was the best model for crossbred heifers (MSPE = 1.25 kg2/d2, mean bias = 0.09 kg/d). These findings indicate that not all available models are adequate for estimating the DMI of dairy heifers managed under a tropical climate, with HHJ and OFNLin for Bos taurus and STA for crossbreds being the most suitable models for DMI prediction. There is evidence that models from Bos taurus heifers could be used to estimate the DMI of heifers under tropical conditions. For heifer ration formulation is necessary to consider that DMI is influenced by breed, diet, management, and climate. Future work should also include animal genetic and environmental variables for the prediction of DMI in dairy heifers.
Jackeline Thais Silva, Evangelina Miqueo, Thaís Manzoni Torrezan, Nathalia Brito Rocha, Giovana Simão Slanzon, Gercino Ferreira Virginio Júnior, and Carla Maris Machado Bittar
Animals MDPI AG
This study aimed to evaluate the performance and metabolic changes in dairy calves fed in a step-up/step-down program and supplemented with lysine and methionine in a milk replacer (MR) or starter concentrate (SC). Male Holstein calves (n = 45) were blocked and distributed in the control without supplementation (1) and with lysine and methionine supplementation in the SC to achieve an intake of 17 and 5.3 g/d, respectively (2), and in the MR to achieve the same daily intake (3). MR was fed 4 L/d until the 2nd week, 8 L/d from the 3rd to 6th week, and 4 L/d from the 7th to 8th week, when calves were weaned. The calves were followed until the 10th week of age. Feed intake was measured daily. Weight and body measurements were registered weekly, and blood samples were collected biweekly. The lysine and methionine intake during the whole period was higher when supplementation occurred via MR. There was a supplementation effect for average daily gain after weaning, and the animals supplemented in the MR had lower BW than those that were not supplemented. Supplementation in MR decreased starter intake at the 10th week and total intake (g DM/d) after weaning. Supplementation with lysine and methionine in the MR or the SC did not benefit the performance or metabolism of dairy calves in the step-up/step-down program. Further studies are needed to understand the effects of amino acid supplementation on feed intake.
Gercino Ferreira Virginio Junior, Maria Eduarda Reis, Ana Paula da Silva, Ariany Faria de Toledo, Amanda Moelemberg Cezar, Lucas William Mendes, Leandro Greco, Horácio Montenegro, Luiz Lehmann Coutinho, and Carla Maris Machado Bittar
PLoS ONE Public Library of Science (PLoS)
β-glucans has been reported to be associated with many health-promoting and improvements in animal performance, however, information about their effects on the bacterial community remains unknown. This study aimed to investigate how the addition of β-glucans can affect the fecal bacterial community with possible consequences on animal growth and health. For this, newborn Holstein calves (n = 14) were individually housed in tropical shelters and blocked according to sex, date, and weight at birth and randomly assigned to one of the following treatments: (1) Control: milk replacer (14% solids, 24% CP, 18.5% fat); (2) β-glucans: milk replacer supplemented with β-glucans (2 g/d). All calves were bucket fed 6 L/d of milk replacer and received water and starter concentrate ad libitum starting on d 2. To evaluate the bacteriome, fecal samples were collected at weeks 1, 2, 4, and 8. The bacterial community was assessed through sequencing of the V3-V4 region of the 16S rRNA gene on the Illumina MiSeq platform and analyzed using the DADA2 pipeline. No differences for Shannon and Chao1 indexes were observed for treatments, but both indexes increased with age (P < 0.001). There were dissimilarities in the structure of the bacterial community during the pre-weaning period (P = 0.01). In a deeper taxonomic level, Collinsella (Actinobacteriota), Prevotella (Bacteroidota), and Lactobacillus (Firmicutes) were the most abundant genera (9.84, 9.54, and 8.82% of the sequences, respectively). β-glucans promoted a higher abundance of Alloprevotella and Holdemanella, which may indicate a beneficial effect of supplementation on dairy calves. The bacterial community was highly correlated with the fecal score at weeks 1 and 2 and with starter concentrate intake at week 8. In conclusion, algae β-glucan supplementation could be beneficial to fecal bacteriome and consequently to the health and performance of dairy calves.
Gercino Ferreira Virgínio Júnior, Ana Paula da Silva, Ariany Faria de Toledo, Milaine Poczynek, Amanda Moelemberg Cezar, Horácio Montenegro, Luiz Lehmann Coutinho, and Carla Maris Machado Bittar
Animals MDPI AG
A starter concentrate containing different levels and sources of NDF can modify the gastrointestinal bacteriome. This study evaluated 18 Holstein calves housed in un-bedded suspended individual cages, fed one of three treatments: 22NDF: a conventional starter containing 22% NDF (n = 7); 31NDF: a starter with 31% NDF, replacing part of the corn by soybean hull (n = 6); and 22Hay: diet 22NDF plus coast-cross hay ad libitum (n = 5). All animals received 4 L of milk replacer daily, weaned at 8th week of age, and housed in wood shelters until week 10. To evaluate the bacteriome, the bacterial community of ruminal fluid and fecal samples was determined by sequencing V3 and V4 region amplicons of the 16S rRNA gene. Bacterial diversity in rumen was not affected by diet or age. The phyla Firmicutes and Bacteroidota, and Prevotella’ genus were the most abundant in ruminal fluid and fecal samples. In feces, the α-diversity indices were higher for 22Hay. All indices were significantly affected by age. We believe that the ruminal bacteriome was affected by basal diet components, but not affected by NDF levels or sources. The supply of hay was effective in modifying the fecal bacteriome of dairy calves due to hind gut fermentation.
Ms Valdemiro Piedade Vigas, Maíra Blumer Fatoretto, Giovana Simão Slanzon, Edwin Moises Marcos Ortega, Clarice Garcia Borges Demétrio, and Carla Maris Machado Bittar
Research in Veterinary Science Elsevier BV
Diarrhea is the most common cause of mortality and morbidity in dairy calves during the first weeks of life. It is responsible for the majority of costs related to animal death and treatments, as well as lower productivity due to reduced weight gain. Therefore, studies that focus on strategies to reduce diarrhea incidence and to improve animal welfare are very important for the dairy industry. For that reason, the beneficial effects of red propolis on the health status of preweaned dairy calves was studied. Animal disease data usually present incomplete observations of interest time, so-called censored observations and one of the statistical techniques for this modeling type is the survival analysis, hence it is a set of methods for analyzing data where the response variable is the time until the occurrence of an event of interest. We propose among some methods of survival data analysis, the long-term models. The motivation to study these models is the fact that part of the population is not susceptible to the event of interest during the period of the study, considered as immune or cured. In this paper, we studied the Weibull distribution in a structure of long-term model, including the covariates in the proportion of cured through the logistic link function. Besides, we used the residual analysis to check the assumptions of the model. The reason for the choice of the Weibull distribution was that this model is very flexibility to model a variety of data sets, among them animal science and long-term survival data. We illustrate its application with a case study from an animal experiment, which examined the time till the occurrence of diarrhea in Holstein calves, where a proportion of the animals were not susceptible to this health condition. This experiment aimed to verify the efficiency of red propolis in disease prevention and the influence of that on the proportion of animals that are not susceptible to diarrhea.
M.E. Reis, A.F. Toledo, A.P. da Silva, M. Poczynek, E.A. Fioruci, M.C. Cantor, L. Greco, and C.M.M. Bittar
Journal of Dairy Science American Dairy Science Association
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.