Calpastatin (CAST) gene is located on the fi fth chromosome of sheep and plays important roles in formation of muscles and meat tenderness after slaughtering. Association of genetic polymorphism in the CAST gene locus MspI and NcoI with body weight was examined in local sheep from Jonggol Animal Science Teaching and Research Unit (JASTRU), Faculty of Animal Science, Bogor Agricultural University. The genotypes for CAST were determined by the PCR-RLFP method. Blood samples were collected from 264 local sheep belonging to JASTRU located in Singosari Village, Bogor District, West Java Province. Extraction of genomic DNA was based on the phenol chloroform method. CAST locus MspI had three genotypes including in MM, MN and NN with frequencies of 0.75, 0.23, and 0.02 respectively. CAST locus NcoI had two genotypes including in MM and MN with frequencies of 0.92, 0.08 respectively. Chi-square test confi rmed Hardy-Weinberg equilibrium for the CAST locus MspI and NcoI. There was no signifi cant eff ects (P>0.05) of CAST locus MspI and NcoI genotypes on body weight of local sheep in JASTRU.

The ADIPOQ and EDG1 genes were responsible in intramuscular fat deposition and marbling scores. This study was aimed to identify polymorphism of indel g.81966364D>I in promoter region of ADIPOQ gene and SNP c.-312A>G in 5' UTR of EDG1 gene in Indonesian beef cattle. Blood samples were collected from 211 cattle, including Bali (44), Madura (20), Pesisir (18), Katingan (20), PO (22), Pasundan (20), SO (12), Brahman (20), Simmental (15) and Limousin (18). Polymorphism of ADIPOQ gene was analyzed using PCR and direct sequencingmethods, whereas EDG1 gene was analyzed using PCR-RFLP (MscI enzyme) and direct sequencingmethods. Results of genotyping indel g.81966364D>I was monomorphic (DD genotype). The SNP c.-312A>G was polymorphic (AA and AG genotype) in Madura, Pesisir, Pasundan, Brahman, and Limousine. The Frequencies of allele A and G were 0.95, 0.92, 0.98, 0.95, 0.94 and 0.05, 0.08, 0.02, 0.05, 0.06 respectively. The values of Ho and He were 0.05-0.17 and 0.05-0.15 respectively and in Hardy-Weinberg equilibrium (P>0.05). In Bali, Katingan, PO, SO and Simmental were monomorphic (GG genotype). In Bali cattle, two novel SNP candidates were found in position of c.-399C>T and c.-273C>G which were potential to be used as genetic markers of marbling score for Bali cattle. As result this study, it can be concluded that ADIPOQ gene was similar while EDG1 gene was different in Indonesian beef cattle. in addition, found two candidates potential SNP in Bali cattle.

Background and Aim: Resistant starch (RS) is difficult to digest in the digestive tract. This study aimed to evaluate the effects of heat-moisture treatment (HMT) on RS in cassava and examined its impact on rumen fermentation. Materials and Methods: Cassava flour was used as a raw material and used in a randomized block design with four different cycles of HMT as the treatments and four different rumen incubations in vitro as blocks. Treatments included: HMT0: without HMT (control), HMT1: one HMT cycle, HMT2: two HMT cycles, and HMT3: three HMT cycles. Heat-moisture treatment processes were performed at 121°C for 15 min and then freezing at -20°C for 6 h. Analyzed HMT cassava starch characteristics included components, digestibility, and physicochemical properties. In in vitro rumen fermentation studies (48 h incubation) using HMT cassava, digestibility, gas production, methane, fermentation profiles, and microbial population assessments were performed. Results: Heat-moisture treatment significantly reduced (p < 0.05) starch, amylopectin, rapidly digestible starch (RDS), and slowly digestible starch levels. In contrast, amylose, reducing sugars, very RDS, RS, and protein digestion levels were significantly increased (p < 0.05). Additionally, a reduced crystallinity index and an increased amorphous index were observed in starch using Fourier-transform infrared analyses, while a change in crystalline type from type A to type B, along with a reduction in crystallinity degree, was observed in X-ray diffraction analyses. Heat-moisture treatment significantly (p < 0.05) reduced rumen dry matter (DM) degradation, gas production, methane (CH4 for 12 h), volatile fatty acid (VFA), and propionate levels. In addition, acetate, butyrate, and acetate/propionate ratios, as well as population of Streptococcus bovis and Bacteroides were significantly increased (p < 0.05). However, pH, ammonia, and organic matter digestibility were unaffected (p < 0.05) by HMT. Conclusion: Cassava HMT altered starch characteristics, significantly increased RS, which appeared to limit rumen digestion activity, decreased rumen DM degradation, gas production, VFAs, and CH4 production for 12 h, but increased S. bovis and Bacteroides levels. Keywords: heat-moisture treatment, in vitro, rumen fermentation, starch modification.

Indonesia is a tropical country with a hot climate. In tropical nations such as Indonesia, heat stress is a key reason for the reduced productivity of dairy cattle. Heat stress is a combination of internal and external stimuli that affects an animal, raises its body temperature, and causes it to react physiologically. Most Indonesian dairy cattle are Friesian Holstein (FH), imported from European nations with a temperate environment with low temperatures in the range of 5°C–25°C. Indonesia has a tropical climate with a high ambient temperature that can reach 34°C during the day and the local relative humidity varies between 70% and 90%. Temperature and humidity are two microenvironment factors that may impact the production and heat release in FH cattle. More than 98% of the entire dairy cattle population in Indonesia is found on Java Island. On Java Island, there are between 534.22 and 543.55 thousand heads of cattle, while the dairy cattle population outside Java Island is just 6.59 thousand heads of cattle. The milk output climbs by an average of 3.34% per year, or approximately 909.64 thousand tons and the average annual growth in whole milk consumption was 0.19 L/capita. Indonesian cow milk output has been unable to keep pace with the country’s increasing demand. This study aimed to review the strategies to mitigate heat stress in FH dairy cattle in Indonesia. Keywords: dairy cattle, heat stress, Indonesia, tropical country.