Genetic improvement of Egyptian cotton (Gossypium barbadense L.) for high yield and fiber quality properties under semi arid conditions.

Between 2016 and 2018, the Agriculture Research Center's Sakha Agriculture Research Station conducted two rounds of pedigree selection on a segregating population of cotton (Gossypium barbadense L.) using the F2, F3, and F4 generations resulting from crossing Giza 94 and Suvin. In 2016, the top 5% of plants from the F2 population were selected based on specific criteria. The superior families from the F3 generation were then selected to produce the F4 families in 2017, which were grown in the 2018 summer season in single plant progeny rows and bulk experiments with a randomized complete block design of three replications. Over time, most traits showed increased mean values in the population, with the F2 generation having higher Genotypic Coefficient of Variance (GCV) and Phenotypic Coefficient of Variance (PCV) values compared to the succeeding generations for the studied traits. The magnitude of GCV and PCV in the F3 and F4 generations was similar, indicating that genotype had played a greater role than the environment. Moreover, the mean values of heritability in the broad sense increased from generation to generation. Selection criteria I2, I4, and I5 were effective in improving most of the yield and its component traits, while selection criterion I1 was efficient in improving earliness traits. Most of the yield and its component traits showed a positive and significant correlation with each other, highlighting their importance in cotton yield. This suggests that selecting to improveone or more of these traits would improve the others. Families number 9, 13, 19, 20, and 21 were the best genotypes for relevant yield characters, surpassing the better parent, check variety, and giving the best values for most characters. Therefore, the breeder could continue to use these families in further generations as breeding genotypes to develop varieties with high yields and its components.

Bovine Leptospirosis in Caatinga Biome, Brazil: New Insights into Diagnosis and Epidemiology.

Bovine leptospirosis causes economic losses and raises public health concerns. It is possible that there are peculiarities in the epidemiology of leptospirosis in regions with a semiarid climate, such as the Caatinga biome in Brazil, where the climate is hot and dry, and the etiological agent require alternative routes of transmission. This study aimed to close knowledge gaps to the diagnosis and epidemiology of Leptospira spp. infection in cows from the Caatinga biome, Brazil. Samples of the blood, urinary tract (urine, bladder and kidney) and reproductive tract (vaginal fluid, uterus, uterine tube, ovary and placenta) were collected from 42 slaughtered cows. Diagnostic tests included were the microscopic agglutination test (MAT), polymerase chain reaction (PCR) and bacterial isolation. Anti-Leptospira spp. antibodies were found in 27 (64.3%) of the animals analyzed using MAT at a 1:50 dilution (cut-off 50), while 31 (73.8%) animals had at least one organ/fluid where the presence of Leptospira spp. DNA was identified, and 29 animals (69%) were positive at bacteriological culture. The highest sensitivity values for MAT were obtained at the cut-off point of 50. In conclusion, even under hot and dry climate conditions, it is possible that Leptospira spp. can spread through alternative routes such as venereal transmission; moreover, a cut-off of 50 is recommended for the serological diagnosis of cattle from the Caatinga biome.

High proportion of cattle and sheep seropositive and renal carriers of Leptospira sp. under semiarid conditions / Alta proporção de bovinos e ovinos soropositivos e portadores renais de Leptospira sp. em condições semiáridas

The aims of this study were to perform serological and molecular detection of Leptospira sp. infection in cattle and sheep under semiarid conditions. Based on a preliminary study performed in our research group, we selected six rural properties showing a positivity ≥ 60% for Sejroe serogroup with titer ≥ 200 measured in serological tests from cattle. In the present study, blood and urine samples were collected from 99 females of reproductive age (51 cattle and 48 sheep) for serological diagnosis, molecular detection and Leptospira sp. attempt to strain recovery. Of the 99 analyzed animals 38.4% (38/99) were positively reactive at the serological tests. Of them, 49% (25/51) were cattle and 27.1% (13/48) sheep. The serogroups detected in cattle were Sejroe (36.8%), Hebdomadis (26.3%), Australis (10.5%), Djasiman (10.5%), Ballum (5.3%), Pomona (5.3%), and Cynopteri (5.3%) with titers of 100–800. In sheep, the reactive serogroups were Australis (27.3%), Ballum (27.3%), Djasiman (18.1%), Tarassovi (9.1%), Icterohaemorrhagiae (9.1%), and Cynopteri (9.1%) with titers of 100–400. Leptospiral DNA was detected in nine urine samples, including five cattle and four sheep. Property 1 showed the highest serological positivity frequencies for both cattle (70.6%) and sheep (70.6%). Similarly, the highest frequency of DNA detection was also found (eight samples, 89%). In this property, we observed the existence of consorted rearing of cattle and sheep with close coexistence between these species. In semiarid conditions, transmission among animals of the same species seems to be the main form of Leptospira sp. dissemination in cattle and sheep herds. However, the contribution of other domestic and wild animals cannot be discarded. The practice of consorted rearing of cattle and sheep and their close coexistence may facilitate the spread of the pathogen in rural properties.

Os objetivos deste estudo foram realizar detecção sorológica e molecular da infecção por Leptospira sp. em bovinos e ovinos em condições semiáridas. Com base em estudo preliminar realizado em nosso grupo de pesquisa, foram selecionadas seis propriedades rurais com soropositividade ≥ 60% para o sorogrupo Sejroe com título ≥ 200 em bovinos. No presente estudo, amostras de sangue e urina foram coletadas de 99 fêmeas em idade reprodutiva (51 bovinos e 48 ovinos) para diagnóstico sorológico, detecção molecular e tentativa de recuperação de estirpesde Leptospira sp. Dos 99 animais analisados, 38,4% (38/99) foram sororeativos nos testes sorológicos. Destes, 49% (25/51) eram bovinos e 27,1% (13/48) ovinos. Os sorogrupos detectados em bovinos foram Sejroe (36,8%), Hebdomadis (26,3%), Australis (10,5%), Djasiman (10,5%), Ballum (5,3%), Pomona (5,3%) e Cynopteri (5,3%) com títulos de 100 a 800. Nos ovinos, os sorogrupos reativos foram Australis (27,3%), Ballum (27,3%), Djasiman (18,1%), Tarassovi (9,1%), Icterohaemorrhagiae (9,1%) e Cynopteri (9,1%) com títulos de 100-400. O DNA leptospiral foi detectado em nove amostras de urina, incluindo cinco bovinos e quatro ovinos. A propriedade 1 apresentou as maiores frequências de positividade sorológica para bovinos (70,6%) e ovinos (70,6%). Da mesma forma, a maior frequência de detecção de DNA também foi encontrada (oito amostras, 89%). Nesta propriedade observou-se a existência de criação consorciada de bovinos e ovinos com estreita convivência entre estas espécies. Em condições semiáridas, a transmissão entre animais da mesma espécie parece ser a principal forma de disseminação de Leptospira sp. em rebanhos bovinos e ovinos. No entanto, a contribuição de outros animais domésticos e selvagens não pode ser descartada. A prática de criação consorciada de bovinos e ovinos e sua estreita convivência podem facilitar a disseminação do patógeno em propriedades rurais.

High proportion of cattle and sheep seropositive and renal carriers of Leptospira sp. under semiarid conditions / Alta proporção de bovinos e ovinos soropositivos e portadores renais de Leptospira sp. em condições semiáridas

The aims of this study were to perform serological and molecular detection of Leptospira sp. infection in cattle and sheep under semiarid conditions. Based on a preliminary study performed in our research group, we selected six rural properties showing a positivity ≥ 60% for Sejroe serogroup with titer ≥ 200 measured in serological tests from cattle. In the present study, blood and urine samples were collected from 99 females of reproductive age (51 cattle and 48 sheep) for serological diagnosis, molecular detection and Leptospira sp. attempt to strain recovery. Of the 99 analyzed animals 38.4% (38/99) were positively reactive at the serological tests. Of them, 49% (25/51) were cattle and 27.1% (13/48) sheep. The serogroups detected in cattle were Sejroe (36.8%), Hebdomadis (26.3%), Australis (10.5%), Djasiman (10.5%), Ballum (5.3%), Pomona (5.3%), and Cynopteri (5.3%) with titers of 100­800. In sheep, the reactive serogroups were Australis (27.3%), Ballum (27.3%), Djasiman (18.1%), Tarassovi (9.1%), Icterohaemorrhagiae (9.1%), and Cynopteri (9.1%) with titers of 100­400.Leptospiral DNA was detected in nine urine samples, including five cattle and four sheep. Property 1 showed the highest serological positivity frequencies for both cattle (70.6%) and sheep (70.6%). Similarly, the highest frequency of DNA detection was also found (eight samples, 89%). In this property, we observed the existence of consorted rearing of cattle and sheep with close coexistence between these species. In semiarid conditions, transmission among animals of the same species seems to be the main form of Leptospira sp. dissemination in cattle and sheep herds. However, the contribution of other domestic and wild animals cannot be discarded. The practice of consorted rearing of cattle and sheep and their close coexistence may facilitate the spread of the pathogen in rural properties.

Os objetivos deste estudo foram realizar detecção sorológica e molecular da infecção por Leptospira sp. em bovinos e ovinos em condições semiáridas. Com base em estudo preliminar realizado em nosso grupo de pesquisa, foram selecionadas seis propriedades rurais com soropositividade ≥ 60% para o sorogrupo Sejroe com título ≥ 200 em bovinos. No presente estudo, amostras de sangue e urina foram coletadas de 99 fêmeas em idade reprodutiva (51 bovinos e 48 ovinos) para diagnóstico sorológico, detecção molecular e tentativa de recuperação de estirpesde Leptospira sp. Dos 99 animais analisados, 38,4% (38/99) foram sororeativos nos testes sorológicos. Destes, 49% (25/51) eram bovinos e 27,1% (13/48) ovinos. Os sorogrupos detectados em bovinos foram Sejroe (36,8%), Hebdomadis (26,3%), Australis (10,5%), Djasiman (10,5%), Ballum (5,3%), Pomona (5,3%) e Cynopteri (5,3%) com títulos de 100 a 800. Nos ovinos, os sorogrupos reativos foram Australis (27,3%), Ballum (27,3%), Djasiman (18,1%), Tarassovi (9,1%), Icterohaemorrhagiae (9,1%) e Cynopteri (9,1%) com títulos de 100-400. O DNA leptospiral foi detectado em nove amostras de urina, incluindo cinco bovinos e quatro ovinos. A propriedade 1 apresentou as maiores frequências de positividade sorológica para bovinos (70,6%) e ovinos (70,6%). Da mesma forma, a maior frequência de detecção de DNA também foi encontrada (oito amostras, 89%). Nesta propriedade observou-se a existência de criação consorciada de bovinos e ovinos com estreita convivência entre estas espécies. Em condições semiáridas, a transmissão entre animais da mesma espécie parece ser a principal forma de disseminação de Leptospira sp. em rebanhos bovinos e ovinos. No entanto, a contribuição de outros animais domésticos e selvagens não pode ser descartada. A prática de criação consorciada de bovinos e ovinos e sua estreita convivência podem facilitar a disseminação do patógeno em propriedades rurais.