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1.
J Dairy Sci ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38278293

RESUMO

With multiparous Jersey cows, colostrum production seems to be variable. Due to this, we aimed to identify specific variables involved in colostrum production and quality. From 2021 to 2023, data from 28 US farms (415 multiparous Jersey cows) were used to investigate if colostrum yield, immunoglobulin G concentration (IgG, g/L), and IgG yield (g) could be predicted by farm variables and transmitting abilities. With the data collected, multiple regression equations were developed to aid in predicting colostrum yield, IgG concentration, and IgG yield. Colostrum was weighed and sampled for IgG analysis. Dairy Herd Information (DHI), calving, diet, and management information data were compiled. Days below 5°C (D <), d above 23°C (D >), and d between 5 and 23°C (D) were recorded. Transmitting abilities for milk, fat, protein, and dollars; previous lactation milk yield, fat percent, fat yield, protein percent, protein yield, previous lactation somatic cell score, previous lactation d open, previous lactation d dry, previous lactation d in milk, and previous parity; current lactation parity, d dry, and calving information, birth ordinal d, and latitude were evaluated. Colostrum yield, IgG yield, and concentration had 1 added to correct for values = 0. After addition, values >0 were transformed to ln or log10. Non-transformed variables were also used to develop the model. Variance inflation factor analysis was conducted, followed by backward elimination. The log10 colostrum yield model (r2 = 0.55; ß in parentheses) included herd size (-0.0001), ordinal d (-0.001), Ln ordinal d (0.07), latitude (-0.02), dry period length (0.004), D < (-0.005), D (-0.003), time to harvest (0.05), Ln time to harvest (-0.35), IgG (-0.004), log10 IgG (0.46), feedings/d (0.06), Ln pasture access (-0.13), and Ln previous lactation d open (0.14). The model showed that previous lactation d open contributed the most toward increasing and latitude contributed the most toward decreasing colostrum yield. The IgG model (r2 = 0.21) included herd size (0.02), D > (0.38), Ln time to harvest (-19.42), colostrum yield (-4.29), Ln diet type (18.00), Ln previous lactation fat percent (74.43), and previous parity (5.72). The model showed that previous lactation milkfat percent contributed the most toward increasing and time from parturition to colostrum harvest contributed the most toward decreasing colostrum IgG concentration. The log10 IgG yield model (r2 = 0.79) included Ln ordinal d (0.03), time to harvest (-0.01), colostrum yield (-0.11), Ln colostrum yield (1.20), Ln pasture access (-0.09), Ln previous lactation fat percent (0.53), and previous parity (0.02). The model showed that colostrum yield contributed the most toward increasing IgG yield, followed by previous lactation milkfat percent. Pasture access contributed the most toward decreasing IgG yield, though the contribution is very small. These models were validated using 39 samples from 22 farms. Actual minus predicted colostrum yield and IgG concentration and yield were 0.89 kg, -21.10 g/L, and -65.15 g respectively. These models indicate that dry period management and cow information can predict colostrum yield, and IgG concentration and yield.

2.
J Dairy Sci ; 106(10): 6894-6902, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37210371

RESUMO

The objective of this study was to assess the growth, apparent total-tract digestibility of nutrients, the prevalence of coccidia, and purine derivatives in postweaning heifers when limit-fed a diet supplemented with sodium butyrate (SB). A 12 wk randomized complete block experiment was conducted using 24 Holstein heifers (92.8 d ± 1.9 d of age and initial body weight [BW] of 99.6 ± 15.2 kg [mean ± standard deviation]). Treatments were 100 g soybean meal (control; CON) and 0.75 g of SB/kg of BW + 100 g soybean meal (SB). Diets were formulated to contain 16.4% crude protein, 2.27 Mcal/kg metabolizable energy (ME), and fed at a feed out rate of 2.15% of BW on a dry matter basis. Intakes were recorded daily while growth measurements and BW were recorded weekly. Urine and fecal samples were taken every 2 wk. On d 42 through d 49 an apparent total-tract digestibility phase took place using acid detergent insoluble ash as a marker. Growth measurements were similar among treatments except CON heifers grew longer and tended to be taller at the withers. A trend was observed for CON animals to have lower levels of coccidian oocytes by week. Heifers fed SB had lower blood glucose levels and higher levels of ketones in their blood. Urinary volume was greater for heifers fed SB throughout the 12 wk study. Total purine derivatives were greater in CON heifers. Dry matter, organic matter and acid detergent fiber digestibilities were greater for heifers fed SB compared with CON heifers. Crude protein, neutral detergent fiber, and ash digestibilities tended to be greater in heifers fed SB than in CON heifers. These results suggested no growth benefit of supplementing SB to limit-fed heifers; however, apparent total-tract fiber, ash, and crude protein digestibilities were improved in the SB fed heifers likely due to improved ruminal and intestinal development.


Assuntos
Doenças dos Bovinos , Coccidiose , Bovinos , Animais , Feminino , Ácido Butírico/metabolismo , Digestão , Detergentes/metabolismo , Ração Animal/análise , Dieta/veterinária , Nutrientes , Peso Corporal , Vitaminas/metabolismo , Coccidiose/metabolismo , Coccidiose/veterinária , Purinas , Rúmen/metabolismo , Doenças dos Bovinos/metabolismo
3.
J Dairy Sci ; 104(8): 8814-8825, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33985776

RESUMO

ß-Carotene, a pro-vitamin A carotenoid, acts as an antioxidant, able to scavenge free radicals to prevent oxidative damage. It has also been shown to increase rumen microbial production in vitro. When supplemented prepartum, ß-carotene increased colostral fat and protein concentrations. The objective of this experiment was to evaluate the effects of supplementing 700 mg/d ß-carotene (BC) daily for 4 wk prepartum on cow performance, colostrum, and performance in subsequent calves. Eighteen multiparous Holstein cows housed in a tiestall barn were blocked by expected calving date and randomly assigned to treatments at 4 wk prepartum. Blood samples were collected 3 times a week for analysis of nonesterified fatty acids, ketones, ß-carotene, and IgG. Urine samples were also collected 3 times a week for analysis of creatinine and purine derivatives. Colostrum was collected within 90 min after parturition. Calves were removed from their dams before suckling, weighed within 30 min of birth, and received 4 L of maternal colostrum. Blood samples were collected from calves before colostrum administration (0 h) and at 24 h via jugular venipuncture for analysis of IgG concentration and apparent efficiency of IgG absorption. The 18 calves born were blocked based on treatments of dams. All calves were fed 449 g/d dry matter of milk replacer (20% crude protein, 20% fat) and an 18% crude protein textured starter and water ad libitum at 2 d of age until weaning at 42 d. There were no differences in any blood parameters of cows during the prepartum period. Supplemental BC increased the solids content of colostrum compared with control (22.89% control; 27.75% BC). Calves born from control fed cows had greater efficiency of IgG absorption than those born from BC supplemented cows (52.16% control; 39.50%, BC). Calves born from BC fed cows had greater feed efficiency (average daily gain/dry matter intake) compared with those born from control supplemented cows (0.33 for control; 0.44 for BC). These data indicate that although supplementing ß-carotene to cows in the prepartum period negatively affects apparent efficiency of IgG absorption, it improved feed efficiency in calves.


Assuntos
Colostro , beta Caroteno , Ração Animal/análise , Animais , Animais Recém-Nascidos , Bovinos , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Imunoglobulina G , Leite , Gravidez
4.
JDS Commun ; 2(6): 393-397, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36337115

RESUMO

Drinking water quality requirements focus mainly on removing hazardous substances from the water supply, making it safe to drink and appropriate for livestock use. However, there is a concern that high mineral content in water may affect the drinking behavior of heifer calves, which may affect health and performance. In South Dakota, the primary water sources for agricultural use are surface or groundwater. Water quality varies between different regions of the state; in the eastern part of the state, the water is classified as "hard water" and calcium is the primary mineral found in the water. Our objective was to determine the water intake and drinking preference of heifer calves offered water treated with a reverse osmosis system (ROW), water treated by a municipal city water treatment plant (TW), and local untreated well water (UWW). Six Holstein heifer calves (100 ± 6.5 d of age; 137 ± 5.9 kg of body weight) were used in a sequential elimination study. The calves were kept in individual pens (1.5 × 3 m) and fed similar pellet and grass hay rations. Three troughs (14 L) of water were provided for each heifer calf and refreshed 3 times per day. Three water types were randomly assigned to the troughs, and an extra trough on each side was left empty to avoid preferential behavior by location. Throughout the 8-d experiment period, the intake of each type of water by each calf was measured. During the study adaptation phase, heifer calves were given TW for 3 d to establish baseline intake. During phase 1, all 3 water types were offered for 3 d. The most-consumed water of each heifer calf was removed after intake data were collected. During phase 2, the remaining 2 water types were offered for 2 d. Water preference ranking by heifer calf was determined based on intake amounts. Kendall's coefficient of concordance (W) was calculated to evaluate the agreement of preference among the heifer calves. The total average water intake was 16.0 ± 2.14, 15.8 ± 1.95, and 14.9 ± 2.21 kg/d for the adaptation phase, phase 1, and phase 2, respectively. During phase 1, average intake was 7.10 ± 3.97, 5.10 ± 3.59, and 3.55 ± 4.89 kg/d for ROW, TW, and UWW, respectively. Three heifer calves preferred ROW first and TW second. Two heifer calves selected TW first and ROW second. One heifer calf chose UWW first and was a potential outlier in the group for taste preference. Average preference rankings were 1.67, 1.83, and 2.50 for ROW, TW, and UWW, with lower numbers indicating greater preference. Overall, most of the heifer calves in the trial showed similar preferences (W = 0.53), meaning that when one heifer calf had a preference for a particular water type, there was a trend for all the calves to prefer that water type. Results showed that the calves slightly preferred ROW over TW, and preferred both ROW and TW over UWW, with greater consumption of ROW when all 3 water types were offered.

5.
J Dairy Sci ; 103(12): 11363-11374, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33041029

RESUMO

Objectives of this study were to determine effects of meloxicam administered in 2 forms on IgG uptake, growth, and health of preweaned calves. Sixteen Holstein bulls and 14 heifers with a body weight (BW) of 44.3 ± 5.24 kg were blocked by birth date in a randomized complete block design. Calves were removed from the dam before suckling, weighed, and randomly assigned to 1 of 3 treatments: (1) colostrum replacer (CR) at 0 h with no meloxicam (control; CON), (2) 1 mg/kg of BW of meloxicam in pill form before CR (PL), or (3) 1 mg/kg of BW of meloxicam mixed in solution with CR (SL). Calves were fed 675 g of dry matter of CR, providing a volume of 3 L and 180 g of IgG. Blood samples were collected at 0 h to analyze initial IgG and ketone concentrations, and at 6, 12, 18, and 24 h to analyze IgG uptake. At 24 h, calves were fed 432 g of dry matter of 24% crude protein milk replacer (MR) split in 2 feedings, and free choice starter and water until 42 d. Weekly blood samples were analyzed for glucose, plasma urea nitrogen, and ketone concentrations. Time of consumption of MR, BW, length, hip and withers height, and heart girth were recorded weekly. All calves achieved adequate transfer of immunity. Meloxicam did not affect apparent efficiency of absorption, serum total protein, or IgG uptake at 6, 18, and 24 h; however, meloxicam-treated calves had lesser IgG concentrations at 12 h (24.40 and 22.59 g/L for PL and SL, respectively) compared with CON (28.47 g/L). Meloxicam treatment did not affect BW. Calves that received PL tended to gain length at a faster rate (0.24 cm/d) than those that received SL (0.19 cm/d). Meloxicam treatment did not affect MR intake, time of consumption of MR, total dry matter intake, or feed efficiency. Meloxicam-treated calves tended to consume more starter (560.4 and 515.4 g/d for PL and SL, respectively) than those that received CON (452.6 g/d). Ketone levels tended to be greater in meloxicam-treated calves (0.15 and 0.17 mmol/L for PL and SL, respectively), suggesting improved rumen development compared with those that received CON (0.12 mmol/L). Meloxicam treatment did not affect plasma urea nitrogen . Glucose concentrations of calves that received PL (73.2 mg/dL) were less than those that received SL (83.3 mg/dL). Results of this study suggest that meloxicam given at 0 h offers positive effects on starter intake, and possibly rumen development, of preweaned dairy calves. Treatment PL, as compared with SL, offered positive results for rumen development, indicated by lower blood glucose levels.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Animais Recém-Nascidos/imunologia , Bovinos/crescimento & desenvolvimento , Bovinos/imunologia , Imunoglobulina G/metabolismo , Meloxicam/administração & dosagem , Animais , Peso Corporal , Colostro , Dieta/veterinária , Ingestão de Alimentos , Feminino , Imunoglobulina G/sangue , Intestino Delgado/metabolismo , Cetonas/sangue , Masculino , Substitutos do Leite , Gravidez , Rúmen/crescimento & desenvolvimento , Desmame
6.
J Dairy Sci ; 103(11): 10207-10218, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32952029

RESUMO

The objective of this study was to evaluate growth and performance of postweaning heifers supplemented with monensin (MON), sodium butyrate (SB), or the combination of MON and SB (MSB) compared with heifers not receiving these feed additives. Forty Holstein heifers [mean age 84.2 ± 1.2 d; body weight (BW) 99.8 ± 10.8 kg (mean ± SD)] were housed in a freestall barn, blocked by birth date, and randomly assigned to 1 of 4 treatments in a randomized complete block design. Treatments were (1) 100 g of soybean meal carrier (control; CON); (2) 0.75 g of SB/kg of BW + carrier (SB); (3) 1 mg of MON/kg of BW + carrier (MON); (4) 1 mg of MON/kg of BW + 0.75 g of SB/kg of BW (MSB). Data were analyzed using single degree of freedom contrasts evaluating CON versus additives (ADD), SB versus MON, and SB and MON versus MSB. Treatments were hand-mixed daily. Feed and orts were measured daily and frozen at -20°C. Orts samples were subsampled for dry matter (DM) determination, and total mixed ration samples were taken weekly and composited monthly for DM and nutrient analysis. Initial BW, heart and paunch girths, body length, blood samples, and fecal coccidia counts were measured before the start and weekly during the 12-wk trial. Blood samples were analyzed for glucose, plasma urea nitrogen (PUN), and ketone concentrations. Apparent total-tract nutrient digestibility was determined from d 21 to 27 and from d 63 to 69 using acid detergent insoluble ash as a marker. Daily dry matter intake (DMI) and metabolizable energy intake were increased in ADD compared with CON, and average BW, final BW, and heart girth tended to increase. Whereas MSB tended to be greater than SB and MON for heart girth, feed efficiency was greater with MON compared with SB. Compared with CON, ADD decreased coccidia counts. No effect of treatment on PUN was detected. Monensin and SB tended to have greater plasma glucose than MSB did. Average blood ketone concentrations were greater with ADD versus CON, in SB versus MON, and in MSB versus SB and MON. During the wk-3 digestibility phase, DMI tended to be greater in heifers fed SB versus MON, as well as in heifers fed MSB versus SB and MON. Digestibility of nutrients were similar, except that starch digestibility was increased in heifers fed MSB versus SB and MON. During the wk-9 digestibility phase, DMI and digestibility of nutrients were similar, except NDF, which tended to be greater in CON than in ADD. Overall, ADD resulted in positive growth and reduced coccidia compared with CON.


Assuntos
Ácido Butírico/administração & dosagem , Bovinos/fisiologia , Dieta/veterinária , Digestão/efeitos dos fármacos , Nível de Saúde , Monensin/administração & dosagem , Ração Animal/análise , Animais , Composição Corporal , Peso Corporal/efeitos dos fármacos , Bovinos/crescimento & desenvolvimento , Doenças dos Bovinos/prevenção & controle , Suplementos Nutricionais , Ingestão de Energia , Feminino , Trato Gastrointestinal/metabolismo , Nutrientes/metabolismo , Rúmen/metabolismo
7.
J Dairy Sci ; 103(6): 5700-5708, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32147255

RESUMO

Regional Research Project NC-2042 has a main objective to study calf and heifer nutrition. Within this objective, feeding the postweaned heifer is considered a major priority to improve the profitability and sustainability of US dairy farms. Through optimizing nutrient utilization by precision feeding, using alternative feeds, high-fiber diets, and feed additives, this research group has worked to enhance dairy heifer nutrition. Research has focused on precision feeding heifers and incorporating high- and low-fiber diets into this system of feeding. This is accomplished by meeting the nutrient needs of the heifer for a desired rate of growth while enhancing total-tract nutrient digestibility, reducing waste and improving profitability. High-fiber forages have been studied as a means of controlling ad libitum dry matter intakes and thus weight gain in heifers. These results provide producers with a means of feeding heifers while reducing costs. Similarly, utilizing alternative feedstuffs in heifer diets has also been a major research area for this group including comprehensive research on distillers co-products, and new protein sources such as camelina and carinata meals. Results indicated that these products can be satisfactorily incorporated into heifer diets. Studying feed additives has also been a function of the research group. Research with Ascophyllum nodosum and cinnamaldehyde indicated that calves find these additives unpalatable and that supplementing cinnamaldehyde to postweaned heifers showed no benefit. However, sodium butyrate and yeast supplementation proved to be beneficial in the growth and feed efficiency of heifers. Research from this group has an effect on heifer feeding, resulting in new information that can aid in the sustainability of dairy farms. This review will focus on the area of postweaned heifer nutrition.


Assuntos
Criação de Animais Domésticos/economia , Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Ração Animal/análise , Animais , Dieta/veterinária , Feminino
8.
J Dairy Sci ; 103(3): 2287-2302, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882224

RESUMO

We evaluated the effects of incremental levels of unprotected nicotinic acid (NA) supplementation prepartum (0, 16, 32, or 48 g/d; CON, 16NA, 32NA, and 48NA, respectively) on colostrum yield and composition and cow and calf performance. Previous research indicated that 48 g/d of NA prepartum increased colostrum IgG concentration. Exact mechanisms for this increase are not clear. The effects of NA supplementation to prepartum cows on growth and performance of their calves have not been studied. Thirty-six multiparous Holstein cows housed in a tie-stall barn were blocked by expected calving date and randomly assigned to treatments at 4 wk prepartum. Blood samples were collected 3 times weekly for analysis of nonesterified fatty acids, ketones, and IgG. Urine samples were also collected 3 times weekly for analysis of creatinine and purine derivatives. Colostrum was collected within 90 min after parturition. Calves were removed from their dams before suckling, weighed within 30 min of birth, and received 4 L of maternal colostrum. The 38 calves born were blocked based on treatments of dams. All calves were fed 449 g dry matter (DM) of milk replacer (19.3% crude protein, 19.5% fat, DM basis) and a textured starter (41% starch, DM basis) at 2 d of age until weaning at 42 d, with water available ad libitum. Feeding NA resulted in linear decreases in DM intake in cows, but colostrum yield was not affected. Yield of metabolizable energy (ME) tended to change cubically, decreasing from control (CON) to 16NA, increasing from 16NA to 32NA, and decreasing from 32NA to 48NA. Concentration of IgG, protein, ash, and solids increased linearly with NA. Concentration of ME showed a tendency to increase quadratically with NA. Yield of IgG, fat, protein, and solids content increased quadratically with NA, while allantoin and total purine derivatives increased linearly. Calf 24-h IgG and apparent efficiency of absorption were not affected by NA. Calf ME intake from colostrum tended to increase quadratically with NA, but calf starter intake was not affected. Feed efficiency of calves increased quadratically with NA. Calf average daily gain changed cubically with NA, decreasing from CON to 16NA, increasing from 16NA to 32NA, and decreasing from 32NA to 48NA. Hip width gain, body length gain, and final body length changed cubically with NA, decreasing from CON to 16NA, increasing from 16NA to 32NA, and decreasing from 32NA to 48NA. Calf blood concentrations of ketones increased quadratically with NA. These data suggest that increasing levels of NA can be fed prepartum to increase colostral components and 32 g/d NA can improve calf performance.


Assuntos
Bovinos/fisiologia , Colostro/imunologia , Suplementos Nutricionais/análise , Metabolismo Energético , Imunoglobulina G/análise , Niacina/administração & dosagem , Ração Animal/análise , Animais , Animais Recém-Nascidos , Dieta/veterinária , Ingestão de Alimentos , Ácidos Graxos não Esterificados/análise , Feminino , Cetonas/análise , Parto , Gravidez , Purinas/urina
9.
J Dairy Sci ; 103(6): 5694-5699, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31785867

RESUMO

Multistate dairy management research project NC-2042, which is part of the National Institute of Food and Agriculture, has devoted an ongoing objective to calf and heifer nutrition and management. Within this objective, colostrum research has been a priority due to continued opportunities to improve this area on US dairy farms. Research has focused on heating colostrum to reduce bacterial populations and pathogens while increasing IgG absorption. Research also identified other proteins that are reduced when heating colostrum. Studies indicated an apparent upper limit to IgG absorption from colostrum fed to calves. Additional studies have shed light on absorption of IgG from colostrum replacers and evaluated the use of lactoferrin and sodium bicarbonate in both maternal colostrum and colostrum replacers. Milk replacer formulation, feeding strategies, and the effect of calfhood nutrition on future performance have also been researched. Finally, water quality and its effect on calves and heifers have been studied. This review focuses on research done by multistate research project NC-2042 member states in the area of colostrum and calf nutrition and management.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Indústria de Laticínios/economia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Estado Nutricional
10.
J Dairy Sci ; 102(4): 3121-3130, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30738684

RESUMO

The objective of this study was to determine the effect of varying levels of sodium butyrate (SB) supplementation in feed on the growth, digestibility, and health of postweaned heifers. Forty Holstein dairy heifers with a mean age of 84 d and average body weight (BW) of 100.9 ± 11.2 kg were housed in a naturally ventilated freestall barn. Heifers were blocked by birth date and randomly assigned to 1 of 4 treatments in a completely randomized block design: (1) 100 g of soybean meal carrier (control), (2) 0.25 g of SB/kg of BW plus carrier, (3) 0.50 g of SB/kg of BW plus carrier, and (4) 0.75 g of SB/kg of BW plus carrier. Carrier with or without SB was top-dressed and hand-mixed into a total mixed ration once daily. Heifers were fed to provide 10% orts. Initial BW, hip and withers heights, heart girth, and body length were measured before the start of the study and every week thereafter until the 14-wk trial was over. Blood samples were obtained and plasma urea nitrogen, plasma glucose, and whole-blood ß-hydroxybutyrate concentrations were determined before the start of treatment and weekly thereafter until the conclusion of the study. Fecal samples were taken before treatment and every other week from each heifer for coccidia counts. Apparent total-tract nutrient digestibility was determined using acid detergent insoluble ash as an internal marker. Each heifer underwent this phase from d 47 until d 54 of the study. Sodium butyrate had a positive effect on average BW and overall BW gain. Feed efficiency tended to improve as SB supplementation increased. Coccidia counts were lowest in the treatment with 0.25 g of SB/kg of BW plus carrier. Sodium butyrate had no effects on skeletal growth or plasma urea nitrogen concentration. Blood glucose concentration decreased linearly and ß-hydroxybutyrate increased linearly with increasing levels of SB supplementation. Sodium butyrate supplementation did not affect apparent total-tract nutrient digestibility. Sodium butyrate supplementation offers positive results in the growth performance and feed efficiency of postweaned heifers.


Assuntos
Ácido Butírico/administração & dosagem , Bovinos/crescimento & desenvolvimento , Ração Animal/análise , Animais , Peso Corporal/efeitos dos fármacos , Bovinos/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Trato Gastrointestinal/metabolismo , Masculino , Nitrogênio/metabolismo , Distribuição Aleatória , Glycine max/metabolismo , Desmame , Aumento de Peso
11.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e641-e652, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29030887

RESUMO

Thirty-six cows were blocked by calving date and randomly assigned to one of three treatments. Cows were on treatments 3 weeks prepartum through 8 weeks post-partum. Treatments were as follows: (i) no direct-fed microbial (DFM) or cellulase and amylase enzymes (C), (ii) 45.4 g/day of DFM (D) or (iii) 45.4 g/day of DFM and 18.2 g/day of enzyme (DE). Total mixed ration fed and refused were measured daily to determine dry matter intake (DMI). Blood samples were taken three times weekly and analysed for ß-hydroxybutyrate, glucose and non-esterified fatty acids. Body weight (BW) was measured weekly. Colostrum was weighed and analysed for IgA and IgG concentration. Calves were fed 4 L of colostrum within 2 hr of birth. Calf blood samples were taken at 0 and 24 hr for analysis of IgA and IgG concentrations and apparent efficiency of absorption. Milk yield was measured daily and samples collected weekly. Initial BW was different among treatments with D being lesser than C or DE treatments. Body weight, weight gain, efficiency of gain, DMI and blood parameters were unaffected. Treatment did not affect colostrum yield. Ash percentage of colostrum tended to increase with D and DE, while IgA and total solids yield decreased with D. Colostrum fat yield was decreased in D and DE. Treatments did not impact BW, serum IgA and IgG concentrations or apparent efficiency of absorption of calves. Post-partum BW, DMI, blood parameters, milk production and composition were unaffected by treatment. However, cows on D gained more BW and tended to have greater efficiency of gain compared to those on DE, but were similar to C. Somatic cell scores were greatest for D. Results indicate that DFM and enzyme supplementation did not improve health and performance of dairy cattle during the pre- and post-partum periods under conditions of this study.


Assuntos
Amilases/farmacologia , Ração Animal/análise , Bovinos/fisiologia , Celulase/farmacologia , Colostro/química , Probióticos/administração & dosagem , Amilases/administração & dosagem , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos , Celulase/administração & dosagem , Dieta/veterinária , Feminino , Imunoglobulina G/sangue , Gravidez , Fenômenos Fisiológicos da Nutrição Pré-Natal
12.
J Dairy Sci ; 100(10): 8451-8454, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28822548

RESUMO

The estimation of Holstein heifer body weight (BW) from heart girth measurements is needed, as many farms do not have animal scales to make the management decisions that require BW. The correlation between heart girth and BW is known to vary with differing animal conformation. The previous equation to correlate the 2 measures for Holstein dairy heifers was done 25 yr ago. Data were derived from 6 US experiment stations that are part of Regional Research Project NC-2042: Management Systems to Improve the Economic and Environmental Sustainability of Dairy Enterprises. After deriving a new equation from a data set of observations and using a second validation data set, it was determined that the equation developed in 1992 was still valid and further equation development was not needed at this time.


Assuntos
Algoritmos , Peso Corporal , Coração/anatomia & histologia , Animais , Bovinos , Feminino , Tamanho do Órgão , Especificidade da Espécie
13.
J Dairy Sci ; 100(4): 2807-2811, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28161168

RESUMO

Deuterium oxide (D2O) dilution methods have been used to assess body composition in live animals. Estimated body water content can be used to predict body fat and protein, and thus, the amount of energy reserves. It is an alternative method to direct chemical analysis and considered a noninvasive technique that is economical and repeatable. Deuterium oxide use is considered easy, safe, and accurate; however, the traditional methods of analyzing D2O are expensive, tedious, and time consuming. The objective of this study was to evaluate the potential for using nuclear magnetic resonance spectroscopy (NMR) to determine body composition in Holstein dairy heifers. Nuclear magnetic resonance is less expensive and requires minutes to calculate the percentage of D2O in the blood. This study used 24 newborn dairy heifer calves blocked by birth and randomly assigned to 1 of 3 treatments: (1) 446 g dry matter (DM) of a conventional milk replacer (MR) [CON; 20% crude protein (CP), 20% fat], (2) 669 g DM of a moderately high protein MR (MOD; 26% CP, 18% fat), or (3) 892 g DM of a moderately high protein MR (aggressive, AGG; 26% CP, 18% fat). All calves had free-choice access to starter and water. Both MR and starter were medicated with decoquinate. During weaning (d 43 to 49), the morning MR feeding ceased. On d 50, all MR feedings ended but starter and water intakes were continuously recorded until d 56. When calves were 50 d of age, a baseline blood sample was taken followed by injection of 300 mg of D2O/kg of body weight in sterile physiological saline (0.9%). The syringes containing the D2O in physiological saline were weighed before and after administration to record the actual dose of D2O injected gravimetrically. After injection, the D2O was allowed to equilibrate with body water for 1 h. Six blood samples were taken over 6 d (1/d) at 1630 h to estimate the dilution of the tracer. The plasma was aspirated and stored at -20°C until further D2O analysis. This new method was validated using 4 calf plasma samples that were sent to an outside laboratory for measurement using an independent validation method. We detected no differences in total body water, protein, fat, or mineral content in calves fed CON, MOD, or AGG; however, results demonstrated that the D2O dilution technique and analysis by NMR is an appropriate and easy method to estimate water, protein, ash, and fat in young heifers.


Assuntos
Composição Corporal , Óxido de Deutério , Ração Animal , Animais , Bovinos , Dieta/veterinária , Feminino , Espectroscopia de Ressonância Magnética , Desmame
14.
J Dairy Sci ; 100(3): 1712-1719, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28041730

RESUMO

The objective of this 70-d study was to determine the effects of the essential oil cinnamaldehyde compared with the ionophore monensin on performance of weaned Holstein dairy heifers. Eighty-four Holstein dairy heifers (91 ± 3.33 d of age; 109 ± 7.55 kg) were housed in a naturally ventilated curtain sidewall, straw-bedded barn in 12 pens with 7 heifers/pen (3.98 m2/head). Heifers were randomly assigned to 1 of 4 treatments in a completely randomized design: (1) control (CON; carrier, 908 g of ground corn), (2) monensin sodium [MON; 1 mg/kg of body weight (BW) + carrier], (3) cinnamaldehyde (CIN1; 1 mg/kg of BW + carrier), or (4) cinnamaldehyde (CIN2; 2 mg/kg of BW + carrier). The treatments were hand-mixed into a 20% crude protein (CP) whole shelled corn and protein pellet mix fed at 2.21 kg/heifer daily. Heifers had access to free-choice hay and water daily. Initial BW and hip heights were taken at the start of the study and every other week thereafter until calves reached 23 wk of age. Blood samples were also taken on each weigh day to determine plasma urea nitrogen, glucose, and insulin-like growth factor-1 concentrations. Fecal samples were taken from the same 3 heifers/pen initially and then at d 28, 56, and 70 of the study for coccidia counts. Cinnamaldehyde had no performance effects on growth, hay intake, hip height, or blood metabolites compared with MON or CON. Average daily gains were 0.98, 0.99, 1.01, and 1.03 kg/d, and average hay intakes per pen were 17.08, 16.34, 18.11, and 17.60 kg/d for CON, MON, CIN1, and CIN2, respectively. Fecal samples by pens indicated the presence of viable coccidia, but the counts were low and not consistent across heifers within each pen. No benefits were associated with supplementing cinnamaldehyde or monensin into grain mixes for weaned heifers.


Assuntos
Acroleína/análogos & derivados , Ração Animal , Monensin/farmacologia , Acroleína/farmacologia , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal , Bovinos , Dieta/veterinária , Feminino , Desmame
15.
J Dairy Sci ; 100(1): 279-292, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27865505

RESUMO

Studies have shown that calves fed milk replacers (MR) with crude protein (CP) concentrations greater than 20%, as typically found in conventional MR, have higher dry matter intakes (DMI) and greater average daily gains (ADG) but consume less starter, which can lead to stress during weaning and reduced rumen development. The greater amount of CP being fed to preweaned calves may alter their nitrogen (N) balance, and excess N may be excreted in the urine. The objective of this study was to determine N utilization in preweaned calves fed diets varying in the amount of CP and MR fed. This study used 24 newborn dairy heifer calves blocked by birth and randomly assigned to 1 of 3 treatments: (1) 446g dry matter (DM) of a conventional MR (CON; 20% CP, 20% fat), (2) 669g DM of a moderately high protein MR (moderate; MOD; 26% CP, 18% fat), or (3) 892g DM of a moderately high protein MR (aggressive; AGG; 26% CP, 18% fat). All calves had ad libitum access to starter and water. Both MR and starter were medicated with decoquinate. During weaning (d 43-49), the morning MR feeding ceased. On d 50, all MR feedings ended; however, starter and water intakes were continuously recorded until d 56. At 5wk of age, urine was collected using urinary catheters for 3d and chromium oxide was administered by bolus at 2g/d for 7d to estimate N efficiency. Calves fed MOD and AGG had similar starter intakes, feed efficiencies, and ADG, with the combined treatments having reduced starter intakes (258 vs. 537g/d), greater ADG (674 vs. 422g/d), and improved feed efficiency (0.57 vs. 0.45 gain:feed) compared with CON calves preweaning. However, DMI and water intake were similar across all treatments. Results from the N utilization phase showed that MOD and AGG treatments had similar but lower N efficiency compared with CON calves (45.5 vs. 52.7%). This could be due to MOD- and AGG-fed calves having greater urine volume and thereby, greater combined urine N output compared with CON calves (17.6 vs. 12.1 g/d). In summary, feeding >0.66kg (DM) from a 26% CP MR increased ADG and improved feed efficiency during the preweaning period but reduced starter intake and lowered N efficiency.


Assuntos
Leite , Nitrogênio , Ração Animal , Animais , Bovinos , Dieta/veterinária , Feminino , Desmame
16.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-960268

RESUMO

@#<p style="text-align: justify;"><strong>INTRODUCTION:</strong> Tourniquet test has been widely used locally and internationally as the cheapest, fastest and most efficient way of diagnosing dengue infection. This is so efficient that the World Health Organization has been active in promoting this as a diagnostic tool for tropical countries like the Philippines.<br /><strong>OBJECTIVE:</strong> To determine the accuracy of the tourniquet test in the diagnosis of dengue infection among patients aged<br /><strong>METHODOLOGY:</strong> The retrospective research design was utilized. These variables were included: the socio-demographic and clinical variables as to the patients' age, gender, body mass index and the presence of co-morbid conditions, clinical manifestations (duration of fever, headache, abdominal pain, rashes and bleeding episodes, hemoglobin level, WBC, Platelets, NS1, IgG, IgM and Hematocri values). Once these were noted, the researcher coded the results. Coding was done in Microsoft Excel.<br /><strong>RESULTS:</strong> Patients were mostly in the 12 to 17 years age group, males (54.1%), in the normal weight category (88.1%) and had no co-morbid conditions (77.1%). Clinical manifestations of dengue included fever of ? 4 days (56%); abdominal pain (61.5%); and gum bleeding (56.4%). As regards laboratory profile of patients, low hemoglobin levels were observed (77.5%); low WBC count (78.9%); low platelet counts (100%); positive for NS1 (71.1%); positive for Immunoglobulin G (82.6%) and Immunoglobulin M (85.3%). There was a 65% accuracy of cases when tourniquet test was performed among patients with dengue. There was a strong correlation between dengue infection and WBC (r=0.915; p=0.028); platelets (r=0.663; p=0.003); hematocrit (r=0.57; p<0.01); Non-Structural Protein 1 (r=.753; p=.031); IgG (r=0.566;p=0.002); IgM (r=0.510; p=0.009) and Tourniquet test (r=0.513; p=0.045). No significant correlation was observed for cases of dengue infection and hemoglobin (r=0.026; p=0.702) and platelets (r=0.026; p=0.702).<br /><strong>CONCLUSIONS:</strong> The dengue infection was found mostly to be in the 12 to 17 years of age; predominantly males. BMI was not found to be significant factor for dengue infection since most cases were in the normal weight category. Clinical presentations of dengue infection commonly observed in this research were fever with a duration of 4 days and above, headache, abdominal pain and gum bleeding. Majority had abnormal levels of hemoglobin, low WBC, and low platelet count. Biomarkers for dengue infection noted in the study were positive NS1, presence of IgG and IgM. Tourniquet test yielded 655 accuracy if the number of petechiae cases is considered. This could indicate that as an initial tool foe diagnostics, presence of it could be considered for dengue infection. Strong correlation with tourniquet test, and laboratory parameters like WBC, platelets, hematocrit, NS1, IgG and IgM were found which are indicative that these variables have strong association to possible infection of dengue. Any abnormalities found within these laboratory parameters must be considered for dengue evaluation.</p>


Assuntos
Humanos , Masculino , Feminino , Adolescente , Imunoglobulina M , Imunoglobulina G , Torniquetes , Gengiva , Hematócrito , Dengue , Hemorragia , Hemoglobinas , Cefaleia
17.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-633602

RESUMO

INTRODUCTION: Tourniquet test has been widely used locally and internationally as the cheapest, fastest and most efficient way of diagnosing dengue infection. This is so efficient that the World Health Organization has been active in promoting this as a diagnostic tool for tropical countries like the Philippines.OBJECTIVE: To determine the accuracy of the tourniquet test in the diagnosis of dengue infection among patients agedMETHODOLOGY: The retrospective research design was utilized. These variables were included: the socio-demographic and clinical variables as to the patients' age, gender, body mass index and the presence of co-morbid conditions, clinical manifestations (duration of fever, headache, abdominal pain, rashes and bleeding episodes, hemoglobin level, WBC, Platelets, NS1, IgG, IgM and Hematocri values). Once these were noted, the researcher coded the results. Coding was done in Microsoft Excel.RESULTS: Patients were mostly in the 12 to 17 years age group, males (54.1%), in the normal weight category (88.1%) and had no co-morbid conditions (77.1%). Clinical manifestations of dengue included fever of ? 4 days (56%); abdominal pain (61.5%); and gum bleeding (56.4%). As regards laboratory profile of patients, low hemoglobin levels were observed (77.5%); low WBC count (78.9%); low platelet counts (100%); positive for NS1 (71.1%); positive for Immunoglobulin G (82.6%) and Immunoglobulin M (85.3%). There was a 65% accuracy of cases when tourniquet test was performed among patients with dengue. There was a strong correlation between dengue infection and WBC (r=0.915; p=0.028); platelets (r=0.663; p=0.003); hematocrit (r=0.57; pCONCLUSIONS: The dengue infection was found mostly to be in the 12 to 17 years of age; predominantly males. BMI was not found to be significant factor for dengue infection since most cases were in the normal weight category. Clinical presentations of dengue infection commonly observed in this research were fever with a duration of 4 days and above, headache, abdominal pain and gum bleeding. Majority had abnormal levels of hemoglobin, low WBC, and low platelet count. Biomarkers for dengue infection noted in the study were positive NS1, presence of IgG and IgM. Tourniquet test yielded 655 accuracy if the number of petechiae cases is considered. This could indicate that as an initial tool foe diagnostics, presence of it could be considered for dengue infection. Strong correlation with tourniquet test, and laboratory parameters like WBC, platelets, hematocrit, NS1, IgG and IgM were found which are indicative that these variables have strong association to possible infection of dengue. Any abnormalities found within these laboratory parameters must be considered for dengue evaluation.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Imunoglobulina M , Imunoglobulina G , Torniquetes , Gengiva , Hematócrito , Dengue , Hemorragia , Hemoglobinas , Cefaleia
18.
J Geophys Res Space Phys ; 121(7): 6647-6660, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27867796

RESUMO

Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (storm time ring current index) value reaching -223 nT. On 22 June 2015 another strong storm (Dst reaching -204 nT) was recorded. These two storms each produced almost total loss of radiation belt high-energy (E ≳ 1 MeV) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 MeV in kinetic energy. The energized outer zone electrons showed a rich variety of pitch angle features including strong "butterfly" distributions with deep minima in flux at α = 90°. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported "impenetrable barrier" at L ≈ 2.8 was pushed inward, but not significantly breached, and no E ≳ 2.0 MeV electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Overall, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.

19.
J Dairy Sci ; 99(10): 8081-8089, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27497895

RESUMO

A growing body of evidence suggests health-promoting effects of kefir consumption on different nonruminant species, leading to the speculation that kefir may act as a probiotic and benefit calf performance and health. Our objectives were to determine effects of feeding kefir on performance and health of calves in the first 70d of life. Thirty 3-d-old female Holstein calves (body weight=38.2±3.1kg) were blocked by initial body weight and assigned randomly to 1 of 3 treatments (1 calf per pen; 10 pens per treatment). Kefir was added to whole milk (vol/vol) at 0:1 (control; KF0), 1:3 (KF1), or 1:1 (KF2) and fed twice per day (0800 and 1600h) from d3 through 45 and then once per day until weaning, which occurred on d50. Pre- and postweaning intake of starter, daily body weight gain, and gain-to-feed ratio exhibited no difference among treatments. Adding kefir to whole milk fed directly to calves had no effect on concentration of blood metabolites collected on d20, 40, and 70. Body length on d50 (weaning) and 70 was greater in kefir-fed calves. Kefir intake improved fecal scores and reduced days with diarrhea during the first 2wk of life. Apparent digestibility of organic matter, ether extract, crude protein, and neutral detergent fiber remained unaffected by treatment. Overall, it appears that directly feeding kefir to calves during the preweaning period did not improve the performance of calves under the conditions of the current study; however, its consumption marginally improved body length and fecal consistency in the first weeks of life, which is an important concern in intensive calf-rearing systems. Feeding kefir to neonatal calves may be a viable approach to improve the health of calves in commercial calf-rearing operations, although to validate its health-promoting effects additional research is needed to investigate its effects under different calf-rearing conditions.


Assuntos
Ração Animal/análise , Dieta/veterinária , Kefir/microbiologia , Leite/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos , Bovinos , Fezes , Feminino , Probióticos/administração & dosagem , Desmame , Aumento de Peso
20.
J Dairy Sci ; 99(5): 3607-3611, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26995118

RESUMO

Within a dairy enterprise, one major cost is raising young calves. Optimizing the feeding programs of dairy calves is imperative for the sustainability and profitability of dairy operations. Essential oils appear to be natural alternatives to antibiotics and function similarly to ionophores. Supplemental antibiotic ionophores have been very successful in improving feed efficiency and rate of gain in calves, as well as decreasing disease incidences; however, calves may be developing resistance to ionophores and the use of antibiotics in animal feeds has been a major concern for consumers. No current research has examined the value or palatability of supplementing essential oils to dairy heifers. The purpose of this sequential elimination experiment was to evaluate the taste preferences of 6 weaned dairy heifers [approximately 3mo old; 95±10.8kg of body weight (BW)] provided with 0 (control), 1, 2, 3, or 4mg/kg of BW of cinnamaldehyde daily. Heifers had 2 d of adaptation to the new feeding regimen before the experiment started and were then offered the 5 experimental diets for 5 d. The most preferred diet was removed and the study continued with the 4 remaining diets. The most preferred diets were again eliminated sequentially, so that only 2 diets remained on d 13 and 14. Each diet was ranked based on the weight of feed refused at the end of each feeding segment. Overall ranking of the 5 treatments were control, 2, 1, 3, and 4mg/kg of BW of cinnamaldehyde. Results indicated that heifers preferred diets without cinnamaldehyde; however, when only cinnamaldehyde diets remained, dry matter intake was not negatively affected regardless of the concentration of cinnamaldehyde provided.


Assuntos
Paladar , Desmame , Ração Animal , Animais , Bovinos , Dieta/veterinária , Comportamento Alimentar , Feminino
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