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Miguel Mellado Lucía M. Treviño María I. Chavez Francisco G. Véliz Ulises Macías-Cruz Leonel Avendaño-Reyes José E. García 《Reproduction in domestic animals》2023,58(1):39-47
The objective of this retrospective study was to assess the effect of receiving a single (n = 50,285) or double (n = 4392) artificial insemination (AI), 12 h apart, within a timed artificial insemination protocol on pregnancy per AI (P/AI) in nulliparous heifers (inseminated with either sex-sorted or conventional semen) and pluriparous Holstein cows in a commercial dairy herd. Also, this study aimed to investigate the relationship between temperature-humidity index (THI) and time of the first AI and fertility. Fertility of cows receiving two AI with normothermia (THI <68) was higher (p < .05) than cows receiving a single AI (42.9% vs. 36.4%). P/AI of cows receiving two AI with severe heat stress (THI >85) was higher (p < .05) than cows receiving a single AI (21.0% vs. 12.6%). Regardless of heat stress conditions, applying the first AI in the morning increased (p < .05) P/AI in cows with double AI than in cows whose first AI occurred in the afternoon (38.4 vs. 33.3%). With moderate heat stress, and sexed-sorted semen, P/AI to timed AI was higher (65.0 vs. 51.9%; p < .05) in heifers receiving double AI than those serviced once. It was concluded that double AI, 12 h apart, enhanced fertility at timed AI than herd mates with a single AI, particularly with heat stress at breeding. 相似文献
23.
Anna Bassols José Angel Robles-Guirado Laura Arroyo Lourdes Soler Natalia García Raquel Pato Raquel Peña Yolanda Saco Ramon Armengol Fermín Lampreave María A. Alava Francesca Canalias Matilde Piñeiro 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(Z1):64-74
24.
Lydia Serrano Xavier Carbonell Robert Savé Oriol Marfà Josep Peñuelas 《Irrigation Science》1992,13(1):45-48
Summary Strawberry plants (Fragaria x annanasa D. cv Chandler) were grown in field plots and in drainage lysimeters under controlled soil moisture regimes. Four irrigation treatments were established by watering the plants when soil water potential reached -0.01, -0.03,-0.05 and -0.07 MPa. The maximum yield was attained at -0.01 MPa soil water potential. Differences in yield were caused by both changes in the number of fruits per plant and in the fresh weight per fruit. Yield reductions were associated with reductions in total assimilation rate resulting from the decreased assimilatory surface area in plants irrigated at lower soil water potentials. The crop water production function calculated on a fruit fresh weight basis resulted in a yield response factor (K
y) of 1.01. 相似文献
25.
26.
Cortés-Avendaño Paola Tarvainen Marko Suomela Jukka-Pekka Glorio-Paulet Patricia Yang Baoru Repo-Carrasco-Valencia Ritva 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):184-191
Plant Foods for Human Nutrition - The evaluation of the level of alkaloids in edible Lupinus species is crucial from a food safety point of view. Debittering of lupin seeds has a long history;... 相似文献
27.
D. Sadiković B. Piškur I. Barnes T. Hauptman D. Diminić M. J. Wingfield D. Jurc 《Plant pathology》2019,68(6):1120-1131
Brown spot needle blight (BSNB), a disease of pine trees caused by the fungus Lecanosticta acicola, has been known in Slovenia since 2008 and in Croatia since 1975. Recent outbreaks in Slovenia prompted this study to compare L. acicola populations in these two neighbouring European countries. Sixty-nine isolates collected from three pine species (Pinus mugo, P. halepensis and P. nigra) were used to determine the phylogenetic relationships, genetic structure, and reproductive strategy of the pathogen. EF1-α sequences showed that Slovenian and Croatian isolates share a common ancestry with individuals from central and northern Europe. Population structure analysis revealed four distinct population clusters of L. acicola in these two countries, generally corresponding to their respective geographic location and host. An unequal ratio of mating types and a low overall genetic diversity in the population indicated a strong influence of asexual reproduction. Although some of the oldest recorded European occurrences of BSNB are from Croatia, this study provided no evidence that the population studied in Croatia was the source of the sampled outbreaks in Slovenia. Recent outbreaks of L. acicola in Slovenia are most likely due to introductions from other, yet to be identified, sources. 相似文献
28.
Histological alterations in gills of shrimp Litopenaeus vannamei in low‐salinity waters under different stocking densities: Potential relationship with nitrogen compounds 下载免费PDF全文
Marcela G. Fregoso‐López María S. Morales‐Covarrubias Miguel A Franco‐Nava Javier Ramírez‐Rochín Juan F Fierro‐Sañudo Jesús T Ponce‐Palafox Federico Páez‐Osuna 《Aquaculture Research》2017,48(12):5854-5863
Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp /m2) were examined weekly over a culture cycle in tanks with low‐salinity water (1.9 g/L) and zero water exchange. Results showed survival rates of 87.7 and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, electrical conductivity and chlorophyll a were not significantly (p > .05) different between modules. In contrast, the concentrations of nitrogen compounds were significantly (p < .05) different between modules, except nitrite‐N (M2 were 2.31 ± 1.38 mg/L N‐TAN, 0.18 ± 0.49 mg/L N‐NO2? and 6.83 ± 6.52 mg/L N‐NO3?; in M1: 0.97 ± 0.73 mg/L N‐TAN, 0.05 ± 0.21 mg/L N‐NO2? and 0.63 ± 0.70 mg/L N‐NO3?). When waters of both modules reached higher levels of ammonia and nitrite, histological alterations were observed in gills. The histological alterations index (HAI) was higher in M2 (5‐112) than in M1 (2‐22). 相似文献
29.
Morphological development and allometric growth of yellowtail kingfish Seriola lalandi V. larvae under culture conditions 下载免费PDF全文
Emmanuel Martínez‐Montaño Karina González‐Álvarez Juan Pablo Lazo Juan Manuel Audelo‐Naranjo Antonio Vélez‐Medel 《Aquaculture Research》2016,47(4):1277-1287
Morphological development and allometric growth patterns of Seriola lalandi larvae were assessed to characterize normal growth patterns under culture conditions. Early ontogenetic stages of yellowtail kingfish exhibited an exponential growth in terms of standard length as a function of age. Five development stages were characterized from hatching to the juvenile stage: larval stage I (0–2 days post hatch, dph) with endogenous feeding, characterized by a small yolk sac, unpigmented eyes, primordial finfold surrounding the body and a closed mouth; larval stage II (2–15 dph) characterized by mouth opening, complete pigmentation of eyes and the beginning of the exogenous feeding; subsequently, in the larval stage III (15–25 dph) the posterior tip of notochord of the larvae bended upward and the first rays appeared in fins, concomitant with a change in swimming behaviour; thereafter, larval stage IV (post‐flexion stage; 25–30 dph) began when larvae resembled in morphology to a juvenile organism; however, caudal and dorsal fins were not completely development. Lastly, the juvenile stage was reached 30 dph characterized by a morphology and fin structures similar to those of the adults. Growth and development of structures and organs associated with vital functions such as feeding, sensorial and breathing systems seemed to be more critical previous to 23 dph, which was reflected with a positive allometric growth of head and eyes during this period. The results from this study can be used as a tool‐guide to assess normal development in larval research with S. lalandi to improve existing rearing protocols in hatchery production. 相似文献
30.
Frederic Vandeperre Ruth M. Higgins Julio Sánchez‐Meca Francesc Maynou Raquel Goñi Pablo Martín‐Sosa Angel Pérez‐Ruzafa Pedro Afonso Iacopo Bertocci Romain Crec’hriou Giovanni D’Anna Mark Dimech Carmelo Dorta Oscar Esparza Jesús M. Falcón Aitor Forcada Ivan Guala Laurence Le Direach Concepción Marcos Celia Ojeda‐Martínez Carlo Pipitone Patrick J. Schembri Vanessa Stelzenmüller Ben Stobart Ricardo S. Santos 《Fish and Fisheries》2011,12(4):412-426
Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta‐analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no‐take area. CPUE of both target species and the marketable catch increased gradually by 2–4% per year over a long time period (at least 30 years). The influence of the size of the no‐take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no‐take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no‐take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs. 相似文献