A series of study aimed to improve egg production, egg quality and immunity resulted by cross-breeding with Arab chickens and laying chickens has been observed on 400 chickens of 5-month old of hens was used and treatment was divided into 2 groups: medium and heavy type hens. Randomized Block Design was used and hens were fed on a laying diet contained 18% of crude protein content and 2900 kcal/kg of metabolism energy. Parameters observed were the number of daily eggs (hen/day), clutch, egg weight, egg shape, shell thickness, Haugh unit (HU) and the total percentage of egg production during one production cycle. Immunity was observed by thymus size and time of thymus regression. The results showed that daily and total egg production, clutch spacing, egg weight, egg shape, hemp thickness, Haugh unit (HU) of egg in both heavy and medium type were significantly higher than pure local chicken. However, all the parameters of egg production and egg quality on the type of weight were significantly higher than the light type. In terms of immunity, time of thymus regression on crossbreed hen type occurred at 14-16 weeks of age. It concluded that crossbreeding between local chicken increased egg production and egg quality on derivatives of local chicken. It was also informed that the immunity of derivatives of local chicken resulted by crossbreeding against endemic diseases was better than that of in natural breed chicken.

Escherichia coli (E. coli) O157:H7 is one of bacteria that recognized as pathogenic agent, both in animals and human. Several isolates of this bacteria were obtained from local livestock, such as in bali cattle and aceh cattle. However, the bacteria found in aceh cattle has not been confirmed through molecular technique. The current study was aimed to confirm the finding of E. coli strain O157:H7 in aceh cattle using molecular analysis. Three isolates of E. coli O157 (MA-35, MA-44, and MA-58) obtained from aceh cattle were extracted for the DNA using Presto™ Mini gDNA bacteria kit (Geneaid) through several processing stages of sample preparation, lysis, DNA binding, washing and elution. Then, it was continued with DNA Amplification Using Polimerase Chain Reaction (PCR). DNA sequencing homology was conducted using BLASTN program. Data of this study were analysed descriptively. The results showed that one of isolate (MA-58) was detected for the presence of genes of rfb (339 bp), fliC (401 bp), and stx2 (115 bp). Then, this isolate has a homology of 100% to 16 different strains of E. coli O157:H7 sequence in the GenBank. In conclusion, the molecular analysis of the local isolate of bacteria of MA-58 obtained from aceh cattle confirmed that it is E. coli O157:H7 and detected with the presence of genes of rfb, fliC, and stx2.

Probiotics are an alternative that can be used to prevent the incidence of vibriosis in the cultivation of tiger shrimp (Penaeus monodon). Yeast can be used as a probiotic and immunostimulant because it can increase the total of beneficial microbes. Lactic Acid Bacteria (LAB) are chosen to be developed as a probiotic because it is able to produce organic acids, hydrogen peroxide and bacteriocin which act as antagonistic agent to Vibrio spp. This study aimed to determine the effect of RABAL probiotics on the total Vibrio spp. in medium of post larvae tiger shrimp (Penaeus monodon). The study was conducted with an experimental method using a completely randomized design (CRD) with 4 treatment groups and 3 repetitions. Calculate of the total amount of Vibrio spp. and LAB on rearing water was carried out using Total Plate Total (TPC) method. Based on the results of the study, it was found that administering RABAL probiotics with a dose range of 2,5 to 7,6 ml / L was proven to reduce the amount of Vibrio spp. in rearing water of post larvae tiger shrimp (Penaeus monodon).

Prior to the novel coronavirus, the subtype H5N1 that emerged in Asia in 2003 and hit Indonesia from 2005 to 2010 has created fears with the public. Attention has not only been detections of domestic fowls but pigeons as well. This study aimed to detect the specific antibody to the avian influenza virus of the H5N1 subtype in pigeons. We collected 20 serum samples of unvaccinated pigeons and tested them using the haemagglutination inhibition test (HI-test). This conventional test is considered as a gold standard, with a specific antigen of the avian influenza virus and a one percent solution of chicken red blood cells as a pre-treatment. The results reported of 20 samples have no specific antibody to the H5N1 subtype of avian influenza. Therefore, It can be concluded that none of the pigeons was infected by the H5N1 subtype of avian influenza virus.

This study aims to describe the quality of E-student worksheet on the concept of vertebrate based on critical thinking in senior hight school. The development research used the Tessmer formative evaluation design, namely: 1) self evaluation; 2) expert reviews; 3) one-to-one evaluation; 4) small group evaluation; and 5) field test evaluation, but in this study only up to small group evaluation. The validity test subjects were three experts, the individual test subjects were three students of class X Senior High School and the small group test subjects were four students in the same class. Expectancy practicality data is obtained from student responses using the expectation practicality assessment sheet instrument. Expected effectiveness data is obtained from the results of the assessment of students' critical thinking skills through the E-student worksheet. The effectiveness of expectations based on the assessment of critical thinking skills in the interpretation aspect obtained a good category, while other aspects including analysis, inference, explanation and self-regulation obtained a very good category. Thus, the quality E-student worksheet on the concept of vertebrate based on critical thinking in senior hight school has a very good category.