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Relatively, little is known about the corpus luteum (CL) function in early pregnancy after the successful treatment of luteal phase deficiency in repeat-breeder dairy cows when exposed to extreme environments under tropical climate. To investigate the influence of increased tissues of corpora lutea (CLs) by inducing secondary CL based on progesterone (P4) concentration and fertility in repeat-breeder dairy cows undergoing the fixed-time artificial insemination (FTAI) protocol, 32 cows were treated with gonadotropin releasing hormone (GnRH) on day 5 post-induction (experiment 1). In experiment 2, 213 cows were bred using the short-term FTAI protocol. On day 5 post-FTAI, cows were divided into two groups: treatment with (GnRH5-treated group) or without (GnRH5-untreated group) GnRH. The temperature-humidity index ranged from 77.3 to 82.8. Cows bearing two CLs had greater P4 concentrations than cows bearing only one CL on their ovaries (P 0.05). Pregnancy rates were greater in GnRH5-treated group than the GnRH5-untreated group (P 0.01). Moreover, repeat-breeder cows bearing two CLs had a greater likelihood of pregnancy (odds ratio = 20.86) than cows bearing only one CL on their ovaries (P 0.01). Under heat stress condition, the results highlighted that increasing luteal tissues by creating secondary CL leads to enhanced peripheral P4 concentrations and improved pregnancy outcomes in repeat-breeder dairy cows.

Incidents of food fraud have occurred worldwide, particularly in the form of meat adulteration. In this study, molecular probes were developed using the Random amplification of polymorphic DNA (RAPD) polymerase chain reaction (PCR) technique in order to identify three beef subspecies–Holstein, Angus, and Taiwan Yellow Cattle. Four RAPD-PCR 10-nucleotide primers were chosen out of a total of 60 primers. The selection was based on the reproducibility of species-specific amplicons able to detect various origins of cattle breeds. The results demonstrated that primer OPK12 produced three unique amplicons (1100 bp, 1000 bp and 480 bp) in Holstein; primer OPK14 generated one amplicon that only appeared in Holstein and Angus (200 bp); primer OPK19 amplified two species-specific amplicons in Holstein measuring 550 bp and 650 bp, respectively. However, due to the relatively lower repeatability of RAPD-PCR, higher and more specific testing repeats were required to increase the accuracy of the conclusion.

This study investigated global gene and protein expression in the small yellow follicle (SYF; 6–8 mm in diameter) tissues of chickens in response to acute heat stress. Twelve 30-week-old layer-type hens were divided into four groups: control hens were maintained at 25 °C while treatment hens were subjected to acute heat stress at 36 °C for 4 h without recovery, with 2-h recovery, and with 6-h recovery. SYFs were collected at each time point for mRNA and protein analyses. A total of 176 genes and 93 distinct proteins with differential expressions were identified, mainly associated with the molecular functions of catalytic activity and binding. The upregulated expression of heat shock proteins and peroxiredoxin family after acute heat stress is suggestive of responsive machineries to protect cells from apoptosis and oxidative insults. In conclusion, both the transcripts and proteins associated with apoptosis, stress response, and antioxidative defense were upregulated in the SYFs of layer-type hens to alleviate the detrimental effects by acute heat stress. However, the genomic regulations of specific cell type in response to acute heat stress of SYFs require further investigation.