Efficacy of ovulation synchronization with timed artificial insemination in treatment of follicular cysts in dairy cows

The efficacy of five ovulation-synchronization protocols with FTAI in treatment of cows diagnosed with follicular cysts was investigated in a nonrandomized study in a single herd. Cows identified with follicular structures >25 mm on two subsequent ultrasonographic (USG) examinations 7–10 days apart (n = 552) were assigned to one of the five treatment regimens on the day of the second USG examination. Treatment regimens were Ovsynch (GnRH-7d-PGF2α-56h-GnRH-16h-FTAI), New-CIDR (as Ovsynch with a new CIDR insert being fitted between days 0 and 7), Reused-CIDR (as New-CIDR but the CIDR insert was previously used for 7 days in another cow), G-New CIDR (Pre-GnRH on day 0 with the New-CIDR regimen being initiated 7 days later), and RG-Ovsynch (Pre-GnRH on day 0 and then every 7 days until detection of a luteal structure upon USG examination; at that point the Ovsynch was initiated). A subset of cows was subjected to ovarian USG examination at the time of PGF2α administration, at insemination, and 8–10 days post-insemination. Progesterone-releasing ability of new and reused CIDR inserts were evaluated in cows diagnosed with severe ovarian inactivity (n = 16). The data were analyzed using logistic regression with pregnancy per AI on days 30 (P/Al 30) and 70 (P/AI 70) post-insemination were included as outcome measures. Compared with Ovsynch, RG-Ovsynch improved the P/AI 30 (OR = 2.6, P = 0.03) and the P/AI 70 (OR = 2.5, P = 0.05). New-CIDR and G-New CIDR were associated with non-significant increase in P/AI 30 (OR = 2.1, P = 0.09 and OR = 2.3, P = 0.07, respectively) and P/AI 70 (OR = 2.01, P = 0.09 and OR = 2.2, P = 0.09, respectively). Reused-CIDR was not associated with improvement in P/AI (P = 0.93 and 0.79 for P/AI 30 and P/AI 70, respectively). RG-Ovsynch had a longer diagnosis-to-FTAI interval (median 24, IQR 17,31). The dominant ovarian structures and the presence of a cyst or a luteal structure at PGF2α administration or at insemination were not associated with P/AI. The new and re-used CIDR inserts produced comparable concentrations of serum progesterone 3 h, 3 days and 7 days post CIDR insertion. In conclusion, the RG-Ovsynch improved the P/AI whereas the New-CIDR and the G-New CIDR regimens tended to increase the P/AI compared with Ovsynch. Marginal differences in P/AI between RG-Ovsynch, New-CIDR, and G-New-CIDR together with prolonged diagnosis-to-FTAI in RG-Ovsynch should be considered if to evaluate the economic value of these regimens

Effect of Dietary Anthocyanin-Extracted Residue on Meat Oxidation and Fatty Acid Profile of Male Dairy Cattle

This research aimed to evaluate the effects of anthocyanin-extracted residue (AER) in the diet of cattle on meat oxidation during storage and on the fatty acid profiles of the meat. Sixteen male dairy cattle (average body weight 160 ± 10.6 kg) were allotted to feed in a completely randomized design (CRD) with four levels of AER supplementation, 0, 20, 40, and 60 g/kg dry matter (DM) in the total mixed ration (TMR). These TMR diets were fed ad libitum to the cattle throughout the trial. At the end of the feeding trial (125 days), all cattle were slaughtered and meat samples from the Longissimus dorsi (LD) muscle were collected to assess meat oxidation and fatty acid profile. The antioxidant effect of AER on meat oxidation was investigated during 14 days of storage based on color, myoglobin redox forms, lipid, and protein oxidation. The results showed meat from cattle fed AER had better color stability, lower oxidation of lipid, protein and myoglobin than did meat from cattle fed the control diet (0 g/kg AER). Furthermore, fatty acid profiles were affected by AER supplementation with an increase in the concentration of n-3 polyunsaturated fatty acids (PUFA). These results support the inclusion of AER supplementation as a natural antioxidant in cattle to reduce meat oxidation and increase PUFA in meat

Effect of Dietary Anthocyanin-Extracted Residue on Meat Oxidation and Fatty Acid Profile of Male Dairy Cattle

This research aimed to evaluate the effects of anthocyanin-extracted residue (AER) in the diet of cattle on meat oxidation during storage and on the fatty acid profiles of the meat. Sixteen male dairy cattle (average body weight 160 ± 10.6 kg) were allotted to feed in a completely randomized design (CRD) with four levels of AER supplementation, 0, 20, 40, and 60 g/kg dry matter (DM) in the total mixed ration (TMR). These TMR diets were fed ad libitum to the cattle throughout the trial. At the end of the feeding trial (125 days), all cattle were slaughtered and meat samples from the Longissimus dorsi (LD) muscle were collected to assess meat oxidation and fatty acid profile. The antioxidant effect of AER on meat oxidation was investigated during 14 days of storage based on color, myoglobin redox forms, lipid, and protein oxidation. The results showed meat from cattle fed AER had better color stability, lower oxidation of lipid, protein and myoglobin than did meat from cattle fed the control diet (0 g/kg AER). Furthermore, fatty acid profiles were affected by AER supplementation with an increase in the concentration of n-3 polyunsaturated fatty acids (PUFA). These results support the inclusion of AER supplementation as a natural antioxidant in cattle to reduce meat oxidation and increase PUFA in meat