Effects of dietary biotin supplementation on performance and hoof quality of Chinese Holstein dairy cows

Alpha-lactalbumin (α-LA) is a major whey protein in bovine and other mammalian milk, which regulates synthesis of lactose. Little is known about its genetic polymorphism and whether can be used as a potential marker for dairy ingredients, milk yield traits, and milk properties. To investigate its polymorphisms and their relationship with milk lactation traits in Chinese Holstein dairy cows, single-strand conformation polymorphism method (PCR-SSCP) and direct sequencing method were used to mark the α-LA gene SNPs. AA (0.7402) and AB (0.2598) genotypes were screened out by PCR-SSCP bands analysis in two independent populations. Direct sequencing revealed that there is one SNP at 1847th (T/C) bp in noncoding region of α-LA gene with highly polymorphic (0.5 < PIC = 0.5623 or 0.5822), of which T is in AA genotype while C in AB. Association analysis also showed that lactose content (p < 0.05) was negatively correlated with fat and protein contents within subgroup, indicating that the SNPs (1847th, T/C) in α-LA gene could be used as a novel potential molecular marker for lactation traits in Chinese Holstein dairy cows.

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Changes of endoplasmic reticulum and mitochondria in mammary epithelial cells during mammogenesis in Chinese Holstein dairy cows

Acta Histochemica ◽

10.1016/j.acthis.2011.08.007 ◽

2012 ◽

Vol 114 (5) ◽

pp. 448-453 ◽

Cited By ~ 5

Author(s):

Bo Qu ◽

Yujun Jiang ◽

Feng Zhao ◽

Jianhua Xiao ◽

Qing Zhang Li

Keyword(s):

Endoplasmic Reticulum ◽

Epithelial Cells ◽

Dairy Cows ◽

Mammary Epithelial Cells ◽

Mammary Epithelial ◽

Chinese Holstein ◽

Holstein Dairy Cows

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Postpartum Uterine Involution and Embryonic Development Pattern in Chinese Holstein Dairy Cows

Frontiers in Veterinary Science ◽

10.3389/fvets.2020.604729 ◽

2021 ◽

Vol 7 ◽

Author(s):

Yuxin Lin ◽

Hongzhen Yang ◽

Muhammad Jamil Ahmad ◽

Yuze Yang ◽

Wucai Yang ◽

...

Keyword(s):

Embryonic Development ◽

Dairy Cows ◽

Gestational Age ◽

Uterine Horn ◽

Holstein Cows ◽

Crown Rump Length ◽

Chinese Holstein ◽

Uterine Involution ◽

Chinese Holstein Cows ◽

Holstein Dairy Cows

Understanding the postpartum uterine involution pattern and embryonic development could facilitate bovine reproduction management, improve reproductive efficiency, and diagnosis of the reproductive disorder, which would contribute to the success of the dairy business. This study aimed to investigate postpartum uterine involution and embryonic developmental patterns or postconceptional marks of embryonic fetal development in Chinese Holstein dairy cows using B-mode ultrasonography. The results revealed a significant decline in the involution period with an increase of parity and age. The uterine involution period was shorter in multiparous cows when compared with cows with lower parities. Consistently, cows over 4 years old recovered faster than younger cows (2 or 3 years). Besides, the elder cows (over 4 years) had a relatively larger size of resumed cervix uteri and horns. Postpartum uterine involution pattern analysis revealed that the reproductive tract recovered very fast during the first 16 days postpartum for all the parity. Results of postconceptional marks of embryo development revealed a slow increase in diameter of the gravid uterine horn and crown-rump length (CRL) before day 60. In contrast, this increase was dramatic and rapid after the 60th day. We also established two models to estimate gestational age based on gravid uterine horn diameter or CRL. A formula was established to determine the gravid uterine horn size during postconceptional on day 30th–day 90th (r = 0.8714, P < 0.01). In addition, a significant positive correlation between CRL and gestational age (r = 0.98151, P < 0.01) was built. In conclusion, these results illustrated that parity and calving age had significant effects on uterine involution in Chinese Holstein cows. Crown-rump length and gravid uterine horn diameter are both efficient for evaluating the embryo growth. These current findings broaden the understanding of basic reproductive pattern in Chinese Holstein cows and could benefit bovine reproductive management primarily in postpartum and early pregnant cows to reduce the calving interval and avoid periparturient metabolic diseases.

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Transcriptome Analysis Reveals Potential Regulatory Genes Related to Heat Tolerance in Holstein Dairy Cattle

Genes ◽

10.3390/genes11010068 ◽

2020 ◽

Vol 11 (1) ◽

pp. 68

Author(s):

Shenhe Liu ◽

Tingting Yue ◽

Muhammad Jamil Ahmad ◽

Xiangwei Hu ◽

Xinxin Zhang ◽

...

Keyword(s):

Dairy Cows ◽

Heat Tolerance ◽

Molecular Mechanisms ◽

High Throughput Sequencing ◽

Principal Component ◽

Production Performance ◽

Value Analysis ◽

Chinese Holstein ◽

Heat Tolerant ◽

Holstein Dairy Cows

Heat stress affects the physiology and production performance of Chinese Holstein dairy cows. As such, the selection of heat tolerance in cows and elucidating its underlying mechanisms are vital to the dairy industry. This study aimed to investigate the heat tolerance associated genes and molecular mechanisms in Chinese Holstein dairy cows using a high-throughput sequencing approach and bioinformatics analysis. Heat-induced physiological indicators and milk yield changes were assessed to determine heat tolerance levels in Chinese Holstein dairy cows by Principal Component Analysis method following Membership Function Value Analysis. Results indicated that rectal temperature (RT), respiratory rate (RR), and decline in milk production were significantly lower (p < 0.05) in heat tolerant (HT) cows while plasma levels of heat shock protein (HSP: HSP70, HSP90), and cortisol were significantly higher (p < 0.05) when compared to non-heat tolerant (NHT) Chinese Holstein dairy cows. By applying RNA-Seq analysis, we identified 200 (81 down-regulated and 119 up-regulated) significantly (|log2fold change| ≥ 1.4 and p ≤ 0.05) differentially expressed genes (DEGs) in HT versus NHT Chinese Holstein dairy cows. In addition, 14 of which were involved in protein–protein interaction (PPI) network. Importantly, several hub genes (OAS2, MX2, IFIT5 and TGFB2) were significantly enriched in immune effector process. These findings might be helpful to expedite the understanding for the mechanism of heat tolerance in Chinese Holstein dairy cows.

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