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Search Results: 1 - 10 of 9753 matches for " reproductive efficiency "
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Efecto de la permanencia de un dispositivo intravaginal con progesterona sobre la eficiencia reproductiva de vaquillonas holando
Callejas,S; Ochionero,P; González Chaves,S.; Cabodevila,J; Cledou,G;
InVet , 2008,
Abstract: the objective of the present work was to evaluate the effect of the presence of progesterone (0.558 g) intravaginal devices for 7 or 8 days on reproductive efficiency. a total of 53 holstein heifers (20-27 month-old; 3.9±0.2 body condition score) were used. heifers were assigned to 2 treatment: 1) m24 7d: day 0, insertion of intravaginal device (0,558 g progesterone) + 2 mg of estradiol benzoate (eb); day 7, device removal and administration of 150 μg of d-cloprostenol; day 8, 1 mg eb; day 9, (fixed timed artificial insemination (ftai); 2) m24 8d: similar to m24 7d, but the permanence of the device was of 8 days. seventeen to 25 days after ftai, heifers returning to estrus were inseminated. pregnancy diagnosis was done by ultrasonography 28 days after ftai (ftai pregnancy) and by transrectal palpation at 60 day after return to estrus (estrus return pregnancy). there was no effect of treatments on pregnancy rate at ftai (63.0 vs. 73.1%), pregnancy rate to detected heat (57.1 vs. 50.0%), general pregnancy rate (77.8 vs. 84.6%), and heat detection rate (70.0 vs. 85.7%) (p>0.05). in conclusion, the device with 0.558 g of progesterone can remain in the vagina for 7 or 8 days without affecting reproductive efficiency of holstein heifers.
A hipertermia durante o estro pode afetar o desempenho reprodutivo de fêmeas suínas
Wentz, Ivo;Bortolozzo, Fernando Pandolfo;Brandt, Guilherme;Heck, Augusto;Bennemann, Paulo Eduardo;Guidoni, Antonio Louren?o;Uemoto, Daniela Aparecida;
Ciência Rural , 2001, DOI: 10.1590/S0103-84782001000400015
Abstract: the objective of this study was to evaluate the effect of hyperthermia at the day of artificial insemination (ai) up to day 13th on reproductive performance of gilts and sows. in the experiment 1, 488 females were divided in two groups according to the rectal temperature: g1= £ 39.5oc (normothermia), and g2 = > 39.5oc (hiperthermia). the females having hyperthermia showed higher return to estrus rate (err), and lower farrowing rate (fr) and litter size (ls) (p<0.05) than females having normothermia. in the second experiment, 764 females were grouped in four groups: g1 = hyperthermia on the day of ai; g2 = hyperthermia on one of the first four days after ai; g3 = hyperthermia in one day of the first two groups, and, g4 = hyperthermia betwen 10-13th day of pregnancy. females having hyperthermia at the day of the first ai and during the first four days after ai, had a higher err and lower fr (p<0.01) in g1 and g2, and lower ls in g1, g2 and g3 (p<0.01), than the females with normothermia. there were not differences among the females havig hyperthermia or normothermia in g4. in the experiment 3, from 102 gilts, 88 were slaughtered from 29 to 34 days after ai. the err were higher (p<0.01)and the pregnant rate (pr) at up to 24 days, the number of viable embryos (nve) and the embryo survival rate (esr) were lower in females having hyperthermia (p<0.05). in conclusion, hyperthermia at the day of the first ai and during the first four days after ai can be deleterious to the female reproductive performance.
Eficiências Reprodutiva e Produtiva em Vacas das Ra?as Gir, Holandês e Cruzadas Holandês x Zebu
Guimar?es, José Domingos;Alves, Nadja Gomes;Costa, Eduardo Paulino da;Silva, Márcio Ribeiro;Costa, Flávio Marcos Juqueira;Zamperlini, Belmiro;
Revista Brasileira de Zootecnia , 2002, DOI: 10.1590/S1516-35982002000300014
Abstract: to evaluate the reproductive efficiency and its relationship with productive traits and genetic composition of a herd, in tropical climate, 113 cows were ssigned to seven crossbreeding levels: 1/2, 3/4, 7/8, 9/16 and 15/16 holstein x zebu, crossbreed pure holstein and gir. the studied traits were: age at calving, calving season, interval from calving to first service, interval from first service to fertile service, number of services, service period, interval calving, reproductive efficiency, lactation period, milk production by lactation order and genetic groups of the herd. analyses of multiple regression, variance and comparison of averages using tukey test were performed in statistical software saeg. the reproductive efficiency was influenced by the age at calving, lactation period, calving interval and genetic composition of the cows, but it was not influenced by milk production and season. the productive indexes were not influenced by the calving season, but were influenced by the genetic composition of the animals. in this study, the reproductive indexes were satisfactory, the zebu cows presented the smallest productive indexes and the taurine ones the smallest reproductive efficiency, probably by larger sensibility to handling.
Efeito do acondicionamento térmico ambiental sobre o desempenho reprodutivo da fêmea suína
Nunes, Christiane Garcia Vilela;Costa, Eduardo Paulino da;Oliveira, Rita Flávia Miranda de;Donzele, Juarez Lopes;Nunes, Ricardo Vianna;Carvalho, Giovanni Ribeiro de;
Revista Brasileira de Zootecnia , 2003, DOI: 10.1590/S1516-35982003000400010
Abstract: the objetive of this experiment was to evaluate a system of thermal artificial condition for gestation sow housing, at ponte nova-mg. a total of 95 cambourough 22? sows from the second parturition were assigned to two treatments. forty-six sows of treatment one were submitted, during the first 35 days of gestation, to a system of controlled thermal artificial condition (fans and aspersion) which were automatically turned on according to the air temperature (vfn). in treatment two, during the same period 49 sows of the same variety as the first ones were submitted to any artificial thermal condition (svfn). from 35 days on of gestation to the parturition, all the animals received the same management. the average room temperature for treatments vfn and svfn were 22.6oc and 23.4oc, respectively. during the hottest hours of the day, this system was efficient to reduce the temperature by 2oc. in spite of such difference, the system could not reduce the room temperature to an adequate level to these animals (18-21oc). for this reason the animals showed high breathing frequency in both treatments, but this was capable to maintain the body temperature of the sows. there were no differences on the evaluated parameters of reprodutive efficiency and progesterone levels. that is why the ventilation and nebulization systems during the autumn is not justified since the temperatures at this time of the year is not high enough to take the animals to a stress condition which could directly affect their reproductive performance.
Characterization of pig farms in the main swine producing regions of Colombia
Díaz,Carlos A; Rodríguez,María N; Vera,Víctor J; Ramírez,Gloria; Casas,Gloria A; Mogollón,José D;
Revista Colombiana de Ciencias Pecuarias , 2011,
Abstract: the goal of this study was to characterize intensive pig farms with inventories of 200 or more sows. farms were located in the three major swine rearing areas of colombia, representing 62% of the national total sow inventory. a random sample of 67 farms was evaluated, considering a 95% confidence level, 10% precision and 50% variability. a survey was applied to each farm, registering health and production indexes within each production stage, such as acclimatization, farrowing, weaning, and growing/finishing. index differences between regions were established (p<0.05) and herd performance was analyzed to identify strengths and weaknesses of the main colombian swine industry. herds in the evaluated regions had a 87.6% farrowing rate, with a total of 11.7 pigs born per litter, of which 10.8 were born alive; and 10 pigs were weaned per litter, with an average production of 22.3 pigs weaned per sow/year. the average slaughter age was 166.1 days with 102.2 kg per pig. indexes established in the present study were similar or higher compared to the ones reported for other countries. these data suggest that colombian swine producers still have great opportunities to increase profitability if production costs decrease and the number of pigs and the amount of pork produced per year is increased.
M. Azam, R. A. Chaudhry, Nazir Ahrnad1 and I. H. Khan
Pakistan Veterinary Journal , 2001,
Abstract: In this study, various parameters of reproductive efficiency of Bhagnari cattle in Pakistan were investigated. For this purpose, data on reproductive performance records of 223 Bhagnari cows maintained at the Government Cattle Farm, Usta Muhammad, Baluchistan from 1975 to 1985 were analyzed. The results showed that the age at puberty for 223 Bhagnari heifers averaged 987.22+14.77 days, the range was 524 to 1827 days. In 73.09% cows the age at puberty ranged between 701 and 1200 days. The winter born heifers showed significantly lower age at puberty than those born in other seasons. The average age at first calving was 1293.6+18.28 days, the range being 763-2150 days. A total of 63.23% cows gave the birth to their first calf between 1101 and 1600 days of age. Among 798 conceptions, 28.45, 51.75 and 14.28% occurred by 1, 2 and 3 services, respectively, with an average conception rate of 48.22%. The average service period for 520 records was 156.48+14.3 days, the range being 25-671 days. Cows calving in summer showed the longest service period, while winter calvers showed the shortest service period, the difference was significant (p<0.05). The average gestation period for 801 gestations was 284+0.7 days. The average length of calving interval for 487 observations was 450.12+5.8 days, the range being 290-783 days. Cows calving in summer showed longer (p<0.05) calving interval than those calving in other seasons. The average reproductive efficiency of Bhagnari Cows was 68.80+0.98%, the range was 30.59-98.91%.
A. Sattar, R. H. Mirza and I. Ahmad
Pakistan Veterinary Journal , 2004,
Abstract: Various parameters of reproductive efficiency of Jersey cows kept at the Livestock Experiment Station, Bhunikey (Pattoki), District Kasur, for the period from 1991 to 2000 were studied. The average values of age at maturity and age at first calving were 615.48 ± 8.23 and 926.48 ± 10.29 days, respectively and the differences of these parameters during different seasons of birth were statistically non-significant. The average calving to first insemination interval, service period and calving interval were 86.65 ± 1.71, 152.66 ± 4.85 and 430.15 ± 4.87 days, respectively. The differences of calving to first insemination interval among cows calved during different seasons were statistically non-significant. But the differences of calving to first insemination interval during 1st lactation were significant (P<0.05) with those of 6th, 7th and 9th lactations. Service period and calving interval in the Jersey cows calved during humid hot season were significantly (P<0.05) shorter as compared to those of cows calved during dry hot and spring seasons. Effect of parity on the service period was non-significant, but the effect of parity on the calving interval was significant (P<0.05), when the difference of calving interval during 7th and 8th lactation was compared. The average number of services per conception was 2.81 ± 0.09. The effect of parity on the number of services per conception was significant (P<0.05). The average gestation period was 277.63 ± 0.21 days. Higher gestation period was observed in cows carrying male calves than those carrying female calves (P<0.05). The frequency of calvings during winter, spring, dry hot, humid hot and autumn seasons was 19.32, 19.20, 9.79, 33.25 and 18.44 percent, respectively.
Comparative Studies on the Reproductive Efficiency of Imported and Local Born Friesian Cows in Pakistan
Amir Ahmed Khan Niazi,M.Aleem
Journal of Biological Sciences , 2003,
Abstract: Reproductive efficiency is the measure of the ability of a cow to become pregnant and produce viable offsprings. The comparative reproductive efficiency of 50 each imported and local born Friesian cows at Bhunikey (Pattoki), Harichand (Charsada) and Quetta (Baluchistan) was studied. It was concluded that age at first calving differed significantly at different locations (P<0.05) for imported and local born cows. The services per conception at Bhunikey and Quetta did not differ significantly for imported and local born but these differed significantly from imported and local born of Harichand. The service period of imported and local born cows at Bhunikey was significantly longer (P<0.05) than cows at Harichand and Quetta did not vary significantly in imported and local born except Harichand. There was no significant difference in milk yield of imported and local born cows at Quetta. However, at Bhunikey and Harichand, imported cows produced significantly (P<0.05) more milk than their progeny and all these classes produced significantly more milk than imported and local born at Quetta.Calving interval of imported and local born cows at Bhunikey was significantly longer (P<0.05) than the Harichand and Quetta but did not differ significantly for imported and local born cows. Mean dry period for imported and local born at Bhunikey is significantly (P<0.05) longer than that of Harichand and Quetta, but there was no significant difference between the imported and local born at different locations.
Relationships between body composition, backfat depth and reproductive efficiency in gilts
P. Superchi,M. Merenda,C. Sussi,A. Sabbioni
Italian Journal of Animal Science , 2011, DOI: 10.4081/ijas.2003.s1.355
Abstract: Intensive genetic selection allowed to obtained gilts attaining just 30-40% of target mature body lean tissue mass and even further less of target mature body fatty tissue mass at the beginning of reproduction activity (Whittemore, 1996). Fat resources of actual gilts are equivalent to 14- 15 mm backfat thickness (P2) at conception (Caugant et al. 1999) and are low in comparison with old genotypes (fat mass twice than lean mass)...
Relationship between serum β-lactoglobulin content during gestation and reproductive efficiency in primiparous sows
Alberto Sabbioni,Mario Baratta,Matteo Lavarini,Valentino Beretti
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2004.219
Abstract: The relationship between β-lactoglobulin (β-LG) serum concentration in sows during the last 8 weeks of gestation and subsequent piglet performance was investigated in 10 Dunel gilts. Two classes of gilts were identified with low (<150 ng/ml) or high (>150 ng/ml) average serum β-LG content. For both low and high content groups, equations were calculated to describe trends in serum β-LG content, respectively y1=10.07e0.0237x (R2=0.3122) and y2=69.00e0.0201x (R2=0.6959), where x is the number of days of gestation. Differences in serum β-LG content between the two groups were highly significant at all weeks (P<0.01 from week 8 to 6 before farrowing; P<0.001 from week 5 to farrowing). No significant differences (P>0.05) between groups were shown for total number of piglets born, born alive, stillborn or mummified and piglet survival rates up until d 21 after farrowing. The group with high serum β-LG content during gestation showed higher litter weights at d 5 (P<0.05) and d 21 (P<0.10) and higher estimated milk production from farrowing to d 5 (P<0.10). The results indicate that serum β-LG content during the final weeks of gestation could be used as an early indicator of reproductive efficiency, and that gilts with high content could be selected to improve herd productivity.
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