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Search Results: 1 - 10 of 90 matches for " heifers "
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Efecto de la suplementación con residuos de destilería del maíz en el comportamiento de novillas en una asociación de gramínea y leucaena
Sánchez,Tania; Lamela,L; López,O;
Pastos y Forrajes , 2010,
Abstract: the objective of this work was to evaluate the effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena. the study was conducted in an area of the experimental station "indio hatuey" , perico municipality, matanzas province, cuba. the prevailing pasture species was panicum maximum cv. likoni and as legume, leucaena leucocephala. eighteen heifers, distributed in a completely randomized design in three groups of six animals, were used; the control group did not receive supplementation (a), and the other two groups were supplemented with corn distillery residues in 10% (b) and 20% (c) of the protein requirements with regards to live weight. the chemical composition, dry matter availability, live weight gain, parasite infestation and hematocrit were determined. when analyzing the daily gain per treatments, significant differences (p<0,05) were found and the highest values were obtained in treatment c (805 g/animal/day); while a and b showed 479 and 572 g/animal/day, respectively. the hematocrit values (between 28,1 and 30,5%), as well as the egg count, were maintained, without significant differences among treatments. the supplementation with distillery corn residues was concluded to influence positively the mean daily gain, and it also maintained the hematocrit values within the recommended range for cattle.
Heifer Body Weight Gain and Reproductive Achievement in Response to Protein and Energy Supplementation While Grazing Dormant Range Forage  [PDF]
Richard C. Waterman, Jason E. Sawyer, Kim K. Kane, Dean E. Hawkins, Mark K. Petersen
Agricultural Sciences (AS) , 2014, DOI: 10.4236/as.2014.513138
Heifers grazing winter range require supplemental nutrients to complement dormant forage to achieve optimal growth and performance. A study was conducted to evaluate nutritional environment and effect of different supplementation strategies for developing heifers grazing dormant winter range. Eighty-four Angus crossbred heifers were stratified by body weight at weaning, allocated to one of six replicated pastures, and randomly assigned one of three supplemental treatments: 1) 908 g/d of a control supplement providing 340 g·hd-1·d-1 of CP with 130 g of rumen undegradable protein (RUP) and 614 MJ of ME (LRUP); 2) 908 g/d of a RUP supplement providing 340 g·hd-1·d-1 of CP with 170 g of RUP and 567 MJ of ME (HRUP); or 3) 1814 g/d of a protein and energy supplement providing 340 g·hd-1·d-1 of CP with 120 g of RUP + 100 g of propionate salt (NutroCalTM, Kemin Industries, Inc.) and 1222 MJ of ME (LRUP + E). Body weights were taken in November, with monthly 12 h shrunk BW from January thru April, and again in September (at time of pregnancy diagnosis). Heifer average daily gain was similar throughout the developmental period except from d125 to d159 where LRUP + E supplemented heifers had greater gains (P < 0.01) than LRUP and HRUP supplemented heifers (0.33, 0.04, and 0.14 ± 0.05 kg/d, respectively). LRUP + E heifers had a greater percentage (P = 0.04) of heifers pubertal at time of artificial insemination compared to LRUP and HRUP heifers (57, 29, and 30, respectively). However, no differences were detected in overall pregnancy rates (P = 0.40). This study indicated that feeding more supplemental energy (i.e., propionate salt, ground milo and corn) allowed lightweight heifers to achieve a greater rate of gain at a key period during development and achieved comparable reproductive success to heifers only receiving supplemental protein.
Plasma retinol concentration in grazing heifers: First data obtained from a dairy herd in the south of Chile
Chihuailaf,RH; González,CS; Wittwer,F; Contreras,PA;
Archivos de medicina veterinaria , 2008, DOI: 10.4067/S0301-732X2008000100009
Abstract: there is no information available about plasma retinol concentration in grazing heifers in chile, for this reason the plasma retinol concentration was measured in dairy heifers grazing during the winter and spring seasons on paddocks in the south of chile. fifteen clinically healthy friesian heifers from a dairy farm located in the valdivia province, chile, aged between 16 and 18 months, were used. the animals were grazing on fertilized natural pastures from july to december. blood samples were taken monthly from each animal and plasma retinol concentrations were determined using reverse-phase high performance liquid chromatography. mean (± sd) plasma retinol concentration was 0.46 ± 0.09 μg/ml with values fluctuating between 0.18 - 0.69 μg/ml. plasma retinol concentration was lower in winter (0.42 ± 0.09 μg/ml, with values fluctuating between 0.18 to 0.57 hg/ml) and higher in spring (0.50 ± 0.09 μg/ml; with values fluctuating between 0.29 to 0.69 μg/ml). the average values obtained in this study constitute the first data currently available in chile regarding plasma retinol concentration in grazing cattle
Efeitos da monensina no desempenho de bezerras leiteiras em crescimento
Salles, Márcia Saladini Vieira;Zanetti, Marcus Antonio;Conti, Renata Maria Consentino;Lima, César Gon?alves de;
Revista Brasileira de Zootecnia , 2001, DOI: 10.1590/S1516-35982001000500024
Abstract: the performance of 32 growing holstein heifers, with average weight of 84 kg and supplemented with monensin, during four months, was studied. the animals supplemented with monensin presented higher weight and hearth girth at 90 and 120 days of experiment, higher weight gain, with value of 26.56% superior than the control animals. no difference was observed for the corporal length, plasma glucose and the height values. the animals fed monensin presented higher height values. the animals supplemented with monensin showed better development. the use of monensin provided reproductive and productive precocity for the replacement dairy heifers.
Intramammary infections during the periparturient period in Argentine dairy heifers
Calvinho,L. F.; Canavesio,V. R.; Iguzquiza,I. A.; Marioni,I.; Puricelli,F. G.; Neder,V. E.; Tarabla,H. D.; Aubagna,M. D.;
Revista argentina de microbiolog?-a , 2007,
Abstract: prevalence of intramammary infections at prepartum and postpartum in primigravid heifers from five dairy herds located in the central dairy area of argentina was determined. mammary secretion samples from 140 heifers (560 mammary quarters) were obtained 14 days prior to the expected calving day and within 7 days after parturition and subjected to bacteriological analysis. no clinical mastitis cases were detected during the study. the number of infected heifers in at least one mammary quarter at pre and postpartum was 87 (62.2%) and 53 (37.8%), respectively. the most prevalent mastitis pathogens at prepartum among samples yielding a positive bacteriological culture were coagulasenegative staphylococci (69.07%), staphylococcus aureus (12.71%) and streptococcus uberis (4.42%). a decrease on isolation frequency of coagulase-negative staphylococci (53.41%) and s. uberis (2.27%) was observed at postpartum, while that of s. aureus showed an increase (21.59%). presence of intramammary infections appeared to be associated with some management conditions. these results highlighted the need to improve diagnosis and control measures in replacement heifers.
Contreras,Genaro A;
Revista MVZ Córdoba , 2009,
Abstract: mastitis in dairy heifers is a problem that has reached remarkable importance since the development of highly specialized dairy operations. the bovine female is susceptible to intramammary infections (imi) from the moment at which the mammary gland is completely developed in the fetus. a number of features, from individual-based variability to environmental and managerial practices can increase or decreased the risk to acquire imi. the bacteria most commonly associated with imi are coagulase negative staphylococcus (cns), however, other pathogens including staphylococus aureus, mycoplasma spp, streptococcus uberis y streptococcus agalactiae, are also ethiological agents of imi. management alternatives for mastitis in dairy heifers are aimed towards the reduction of risk factors, and are complemented by the inclusion of teat sealants, disinfectants, and antibiotics, in addition to a prior evaluation of herd health programs in each dairy farm.
Systemic Dexamethasone and its Effect on Normal Aerobic Bacterial Flora of Cow
Gholam-Ali Kojouri,Azizollah Ebrahimi,Farzaneh Nikookhah
Pakistan Journal of Biological Sciences , 2007,
Abstract: This study was carried out on 17 Holestein, heifers, aged between 1 to 2 years for determining the normal aerobic bacterial flora and their changes after dexamethasone injection. Swab samples were taken from eye, ear, pharynx and vagina before and 5 days after twice dexamethasone treatment. Results indicated that Bacillus cereus and Corynebacterium pseudotuberculosis had higher frequency of isolations than the other bacterial flora in eye, ear and pharynx. Actinomyces pyogenes was isolated with considerable frequency from vagina. Klebsiella pneumoniae was also isolated from pharynx and its frequency was increased significantlyafter dexamethasone injection (p<0.05).
Molecular Typing of Mastitis-Causing Staphylococcus aureus Isolated from Heifers and Cows
Lívia Castelani,Aline Franciele Silva Santos,Mariana dos Santos Miranda,Luiz Francisco Zafalon,Claudia Rodrigues Pozzi,Juliana Rodrigues Pozzi Arcaro
International Journal of Molecular Sciences , 2013, DOI: 10.3390/ijms14024326
Abstract: Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolates of S. aureus from mammary glands of primiparous heifers were collected in the prepartum, calving and during lactation. For lactating cows, a total of 27 isolates of S. aureus from mammary glands were collected during lactation. The samples were taken in two dairy farms located in Sao Paulo State, Brazil. The highest frequency of S. aureus isolation in heifers was at the end of lactation. Strains were typified through Pulsed-field gel electrophoresis (PFGE) and grouped according to patterns of restriction enzyme SmaI. PFGE generated seven clonal profiles that were grouped into three different lineages, with the LA lineage being predominant and identified in heifers, as well as in the cows from the two regions studied. It was concluded that the cows showed a significant source of dispersion of S. aureus. At the first lactation the heifers were infected by the same clonal profiles of S. aureus which were isolated from multiparous lactating cows. The heifers were infected during milking over the months of lactation.
The Effect of nutritional levelon on advancingage at puberty in nelore heifers
Marco Aurélio Romano,Walquiria Hippolito Barnabe,Antonio Euvídio Dias Feliciano e Silva,Alfredo Ribeiro de Freitas
Ambiência , 2005,
Abstract: The objective of this study was to verify the effect of nutritional level on advancing age at Renata puberty in Nelore heifers. Thirty-one animals at 6 months of age were randomly assigned in two groups: GI, or control, with 15 heifers that received a basal diet, and GII, or supplemented, with 16 heifers that received a diet with higher energy and crude protein levels. The development of the animals was accompanied by weighing them at 21-day intervals to verify the daily weight gain from 6 months to puberty. The diets were readapted when necessary. The reproductive status was monitored by ultrasound every two days; and by progesterone concentrations from blood samples drawn twice a week. The ovulation was determined when progesterone concentrations were higher than 1 ng/mL in three consecutive samples, and by ultrasound images of corpus luteum; and oestrous behavior in some animals. The GII group manifested puberty at 16.33 ±0.89 months of age and GI at 20.58 ±1.83 months of age (p less 0.05). The mean weight at puberty was 302.33 ±21.31Kg for GI and 326.19 ±27.78Kg for GII. The daily weight gain was 0.647 ±0.08Kg for GII and 0.447 ±0.03Kg for GI (p < 0 .05). Progesterone levels at puberty were 2.7801 ±0.27 ng/mL for GI and 2.5747 ±0.26 ng/mL to GII. Only 13% of all heifers manifested oestrous behavior. The nutritional supplementation decreased the age of puberty onset in GII and both groups manifested puberty earlier than heifers feeding only on pasture in Subtropical conditions. It is possible to have an earlier puberty onset in Nelore heifers through nutritional supplementation, without negative effects on their reproductive physiology.
Delaying Postpartum Supplementation in Cows Consuming Low-Quality Forage Does Not Alter Cow and Calf Productivity  [PDF]
J. Travis Mulliniks, Jason E. Sawyer, Richard C. Waterman, Mark K. Petersen
Agricultural Sciences (AS) , 2016, DOI: 10.4236/as.2016.79060
Reducing the amount of supplemental feed postpartum without affecting productivity may enhance profitability of cow-calf operations. Therefore, sixteen 2-yr-old fall calving cows were used to evaluate effects of delaying postpartum supplementation on milk production, serum metabolites, and cow and calf BW change. Cows were stratified by calving date and randomly assigned to one of two treatments: 908 g/d of a 46% CP supplement beginning 5 d postpartum (Supp5, n = 7); or 908 g/d of the same supplement beginning 30 d postpartum (Supp30, n = 9). Supplements were formulated to provide 425 g/d of CP with 225 g coming from ruminally undegradable protein (RUP), and were fed twice weekly. Cows were daily fed 8.2 kg chopped sudangrass hay (5.5% CP, 74% NDF, OM basis) during lactation. Cows and calves were weighed before feeding on two consecutive days on d 0, d 30, and d 80 postpartum. Milk production and constituents were evaluated on d 90. Cow BW was not different at d 0 (P = 0.21) and 80 (P = 0.12) between treatment groups. Cows receiving supplement starting on d 5 postpartum were heavier (P = 0.04) than Supp30 cows on d 30. However, no differences (P ≥ 0.17) were found in BW change or ADG during the duration of the study. Milk production was similar (P = 0.99) for postpartum supplementation treatments. No differences (P ≥ 0.27) were observed in milk fat, lactose, protein, or solids-non-fat. However, there was a tendency (P = 0.09) for milk urea nitrogen to be greater for cows receiving supplement on d 5 than d 30 of lactation. Serum urea nitrogen was greater (P = 0.02) in cows receiving Supp5 than cows receiving Supp30. Serum non-esterified fatty acid (NEFA) and glucose concentrations were not different (P ≥ 0.40) between treatment groups. Calf BW and average daily gain (ADG) was not influenced (P ≥ 0.81) by timing of initial postpartum supplementation. These results indicate that withholding supplementation during the first 30 d postpartum may change pattern of cow BW loss without affecting net BW loss, milk production, or calf growth. Therefore, timing of postpartum supplementation can be manipulated to reduce amount of feed provided without sacrificing cow or calf productivity.
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