Erratum to "Reproductive performance of early- and late-calving dairy cows artificially inseminated after ovulation synchronization and estrous resynchronization or artificially inseminated after observed estrus" (JDS Commun. 2:80-85).

[This corrects the article DOI: 10.3168/jdsc.2020-0035.].

Reproductive performance of early- and late-calving dairy cows artificially inseminated after ovulation synchronization and estrous resynchronization or artificially inseminated after observed estrus.

Within seasonal dairy systems, cows that calve late in the calving season are less likely to become pregnant and maintain a yearly calving interval. Very few studies have examined effective strategies for reproductive management of these late-calving cows. The objectives were to evaluate the reproductive performance of early- and late-calving dairy cows that were either inseminated after observed estrus (control) or enrolled in a timed AI and resynchronization protocol [progesterone (P4) Ovsynch Resynch)]. Early-calving cows calved during the first week of the calving season, whereas late-calving cows calved after 6 wk but were at least 10 d in milk at study commencement. Three dairy herds participated in the study with 391 cows total. Within each calving group, cows were randomly assigned to P4 Ovsynch Resynch or control (no treatment) in a 2 × 2 experimental design. Artificial insemination continued for 6 wk after mating start date (MSD) and was followed by 6 wk of natural service. The interval from MSD to AI was shorter (11.7 vs. 14.7 d) and the 3-wk pregnancy rate (49.5 vs. 21.2%) and the 6-wk pregnancy rate (60.8 vs. 42.4%) were greater in the early-calving compared with the late-calving control cows. By design, synchronized cows received timed AI on MSD and were not included in the statistical analysis of submission rate and interval from MSD to AI. The proportion of cows that received a second AI was not increased by the progesterone-based resynchronization strategy but was greater in early-calving compared with late-calving cows. The 12-wk pregnancy rate was greater (64.5 vs. 45.0%) in the early-calving synchronized cows compared with the late-calving synchronized cows. The interval from MSD to pregnancy was 6 and 12.6 d shorter for synchronized compared with control cows in the early- and late-calving groups, respectively. The results demonstrated reduced reproductive performance of late-calving cows compared with early-calving cows. Nonetheless, a major improvement to reproductive performance was achieved by targeting late-calving cows with a synchronization program, even when cows were only 20 to 50 DIM at first AI. Resynchronization of estrus with a progesterone device only, however, was not sufficient to increase the proportion of nonpregnant cows that received a second AI.

Lymphocyte proliferative responses in dairy cows supplemented with an immunomodulatory feed additive and administered polyvalent vaccination / [Proliferação de linfócitos em vacas leiteiras suplementadas com um aditivo alimentar imunomodulador e vacinadas com vacina polivalente]

O presente estudo avaliou o efeito da suplementação com OmniGen-AF® na proliferação de linfócitos e títulos de anticorpos após vacinação em bovinos leiteiros. Amostras de sangue periférico foram coletadas de 32 vacas leiteiras para quantificação dos títulos de anticorpos anti-Leptospira, e amostras de sangue periférico de 16 vacas leiteiras foram também coletadas para avaliação da proliferação de linfócitos. Observou-se que a suplementação com OmniGen-AF® aumentou a proliferação basal de linfócitos (sem estímulos) 21 dias após a vacinação (P=0,03), apesar de reduzir a proliferação de linfócitos B quando estimulada com Leptospira borgpetersenii serovar Hardjo inativada pelo calor (P=0,03). Ademais, nenhum efeito da suplementação sobre a proliferação de linfócitos no momento imediatamente anterior à vacinação e nos títulos de anticorpos anti-Leptospira foi encontrado. Além disso, a proliferação de linfócitos estimulada com lipopolissacarídeos foi maior em vacas multíparas que em primíparas 21 dias após a vacinação (P=0,03). Desse modo, o presente estudo demonstra que a suplementação com OmniGen-AF® não afetou de forma robusta a proliferação de linfócitos e os títulos de anticorpos anti-Leptospira após vacinação em vacas leiteiras sadias.(AU)

Effects of supplemental calcium salts of palm oil and chromium-propionate on insulin sensitivity and productive and reproductive traits of mid- to late-lactating Holstein × Gir dairy cows consuming excessive energy.

This experiment compared insulin sensitivity, milk production, and reproductive outcomes in dairy cows consuming excessive energy during mid to late lactation and receiving in a 2 × 2 factorial design (1) concentrate based on ground corn (CRN; n = 20) or including 8% (DM basis) of Ca salts of palm oil (CSPO; n = 20), and (2) supplemented (n = 20) or not (n = 20) with 2.5 g/d of Cr-propionate. During the experiment (d 0-203), 40 multiparous, nonpregnant, lactating 3/4 Holstein × 1/4 Gir cows (initial days in milk = 81 ± 2; mean ± SE) were offered corn silage for ad libitum consumption, and individually received concentrate formulated to allow diets to provide 160% of their daily net energy for lactation requirements. From d -15 to 203, milk production was recorded daily, blood samples collected weekly, and cow body weight (BW) and body condition score (BCS) recorded on d 0 and 203. For dry matter intake evaluation, cows from both treatments were randomly divided in 5 groups of 8 cows each, and allocated to 8 individual feeding stations for 3 d. Intake was evaluated 6 times/group. Glucose tolerance tests (GTT; 0.5 g of glucose/kg of BW) were performed on d -3, 100, and 200. Follicle aspiration for in vitro embryo production was performed via transvaginal ovum pick-up on d -1, 98, and 198. Mean DMI, net energy for lactation intake, as well as BW and BCS change were similar across treatments. On average, cows gained 40 kg of BW and 0.49 BCS during the experiment. Within weekly blood samples, CRN cows had lower serum concentrations of glucose, insulin, fatty acids, and insulin-to-glucose ratio compared with CSPO cows, suggesting increased insulin sensitivity in CRN cows. During the GTT, insulin-sensitivity traits were also greater in CRN versus CSPO cows. Supplemental Cr-propionate resulted in lower serum insulin concentrations and insulin-to-glucose ratio within CRN cows only, indicating that Cr-propionate improved basal insulin sensitivity in CRN but not in CSPO cows. During the GTT, however, Cr-propionate supplementation reduced hyperinsulinemia and insulin-to-glucose ratio across CSPO and CRN cows. Milk production, as well as number of viable oocytes collected and embryos produced within each aspiration, were not affected by treatments. Hence, replacing corn by Ca salts of palm oil in the concentrate did not improve insulin sensitivity in Holstein × Gir dairy cows consuming excessive energy during mid to late lactation, whereas Cr-supplementation was effective in improving basal insulin sensitivity in cows not receiving Ca salts of palm oil.

Supplementing an immunomodulatory feed ingredient to modulate thermoregulation, physiologic, and production responses in lactating dairy cows under heat stress conditions.

This study compared vaginal temperature, physiologic, and productive parameters in lactating dairy cows supplemented or not with Omnigen-AF (Phibro Animal Health, Teaneck, NJ) during the summer months in a tropical environment. Thirty-two lactating, primiparous (n = 16) and multiparous (n = 16) pregnant Holstein × Gir cows were ranked by parity, days in milk, body weight, and body condition score (BCS), and assigned to receive (SUPP; n = 16) or not (CON; n = 16) Omnigen-AF (Phibro Animal Health, Teaneck, NJ) at 56 g/cow daily (as-fed basis). During the experimental period (d -6 to 56), cows were maintained in a single drylot pen with ad libitum access to water and a total mixed ration, and milked twice daily. Cows received Omnigen-AF mixed with 200 g of corn (as-fed basis) after the daily morning milking through self-locking head gates, whereas CON cows concurrently received 56 g of kaolin mixed with 200 g of corn. For feed intake evaluation, cows from both treatments were randomly divided in 4 groups of 8 cows each, and allocated to 8 individual feeding stations for 3 d. Intake was evaluated 4 times per group from d 1 to 56. From d -6 to 0, d 15 to 28, and d 43 to 56, cow vaginal temperature was recorded hourly. Environmental temperature-humidity index (THI) was also recorded hourly from d 15 to 28 and d 43 to 56. Cows were evaluated for body weight and BCS on d -6 and 56, individual milk production was recorded daily from d -6 to 56, and milk samples were collected on d -6, 0, 7, 14, 21, 28, 35, 42, 49, and 56 for analyses of somatic cell count and milk components. Blood samples were collected on d -6, -3, 0, 9, 15, 18, 21, 24, 27, 36, 45, 48, 51, 54, and 56. Results from samples or observations collected from d -6 to 0 were included as an independent covariate in each respective analysis. Environmental THI was 74.2 ± 0.5 and cows were exposed to THI >68 for 633 h within a total of 672 h of evaluation. Cows assigned to CON had greater vaginal temperature on d 28, 43, 45, and from d 48 to 55 (by 0.38 to 0.52%), as well as greater mean somatic cell count (by 97%) and serum haptoglobin concentrations (by 89%) compared with SUPP cows. Cows assigned to SUPP had greater mean dry matter intake (by 7%), BCS on d 56 (by 11%), and mean serum insulin concentrations (by 35%) compared with CON cows. Hence, SUPP ameliorated hyperthermia, improved nutritional status, and modulated systemic and mammary gland immune parameters in lactating dairy cows exposed to heat stress conditions.

Effects of concentrate type and chromium propionate on insulin sensitivity, productive and reproductive parameters of lactating dairy cows consuming excessive energy.

This experiment compared insulin sensitivity parameters, milk production and reproductive outcomes in lactating dairy cows consuming excessive energy, and receiving in a 2×2 factorial arrangement design: (1) concentrate based on ground corn (CRN; n=13) or citrus pulp (PLP; n=13), and (2) supplemented (n=14) or not (n=12) with 2.5 g/day of chromium (Cr)-propionate. During the experiment (day 0 to 182), 26 multiparous, non-pregnant, lactating Gir×Holstein cows (initial days in milk=80±2) were offered corn silage for ad libitum consumption, and individually received concentrate formulated to allow diets to provide 160% of their daily requirements of net energy for lactation. Cow BW and body condition score (BCS) were recorded weekly. Milk production was recorded daily and milk samples collected weekly. Blood samples were collected weekly before the morning concentrate feeding. Glucose tolerance tests (GTT; 0.5 g of glucose/kg of BW) were performed on days -3, 60, 120 and 180. Follicle aspiration for in vitro embryo production was performed via transvaginal ovum pick-up on days -1, 82 and 162. No treatment differences were detected (P⩾0.25) for BW and BCS change during the experiment. Within weekly blood samples, concentrations of serum insulin and glucose, as well as insulin : glucose ratio were similar among treatments (P⩾0.19), whereas CRN had less (P<0.01) non-esterified fatty acid concentrations compared with PLP (0.177 v. 0.215 mmol/l; SEM=0.009). During the GTT, no treatment differences were detected (P⩾0.16) for serum glucose concentration, glucose clearance rate, glucose half-life and insulin : glucose ratio. Serum insulin concentrations were less (P=0.04) in CRN supplemented with Cr-propionate compared with non-supplemented CRN (8.2 v. 13.5 µIU/ml, respectively; SEM=1.7), whereas Cr-propionate supplementation did not impact (P=0.70) serum insulin within PLP cows. Milk production, milk fat and solid concentrations were similar (P⩾0.48) between treatments. However, CRN had greater (P<0.01) milk protein concentration compared with PLP (3.54% v. 3.14%, respectively; SEM=0.08). No treatment differences were detected (P⩾0.35) on number of viable oocytes collected and embryos produced within each aspiration. In summary, feeding a citrus pulp-based concentrate to lactating dairy cows consuming excessive energy did not improve insulin sensitivity, milk production and reproductive outcomes, whereas Cr-propionate supplementation only enhanced insulin sensitivity in cows receiving a corn-based concentrate during a GTT.

Physiologic, health, and production responses of dairy cows supplemented with an immunomodulatory feed ingredient during the transition period.

This study compared physiological, health, and productive parameters in dairy cows supplemented or not with Omnigen-AF (OMN; Phibro Animal Health, Teaneck, NJ) during the transition period. Thirty-eight nonlactating, multiparous, pregnant Holstein × Gir cows were ranked by body weight (BW) and body condition score (BCS), and assigned to receive (n=19) or not (CON; n=19) OMN at 56 g/cow daily (as-fed basis) beginning 35 d before expected date of calving. Before calving, cows were maintained in single drylot pen with ad libitum access to corn silage, and received (as-fed basis) 3kg/cow daily of a concentrate. After calving, cows were moved to an adjacent drylot pen, milked twice daily, offered (as-fed basis) 35kg/cow daily of corn silage, and individually received a concentrate formulated to meet their nutritional requirements after both milkings. Cows received OMN individually as top-dressing in the morning concentrate feeding. Before calving, cow BW and BCS were recorded weekly and blood samples were collected every 5 d beginning on d -35 relative to expected calving date. After calving and until 46 d in milk, BW and BCS were recorded weekly, individual milk production was recorded, and milk samples were collected daily for total solids and somatic cell count analyses. Blood was sampled daily from 0 to 7 d in milk, every other day from 9 to 21 d in milk, and every 5 d from 26 to 46 d in milk. On 30 and 46 d in milk, cows were evaluated for endometritis via cytobrush technique, based on % of polymorphonuclear (PMN) cells in 100 total cell count (PMN + endometrial cells). On 48.7±1.6 d in milk, 9 cows/treatment received a lipopolysaccharide (LPS) injection (0.25µg/kg of BW), and blood was sampled hourly from -2 to 8 h, at 12-h intervals from 12 to 72 h, and at 24-h intervals form 96 to 120 h relative to LPS administration. No treatment differences were detected on BW, BCS, serum concentrations of cortisol, fatty acids, insulin, glucose, haptoglobin, cortisol, and insulin-like growth factor-I. Cows receiving OMN had greater milk yield (30.3 vs. 27.1kg/d) and percentage of PMN cells in endometrial cell population (12.2 vs. 3.9%) compared with CON cows. After LPS administration, cows receiving OMN had greater mean serum haptoglobin (212 vs. 94 µg/mL), as well as greater serum concentration of tumor necrosis factor α at 1, 2, and 3 h relative to LPS injection compared with CON cows. In conclusion, OMN supplementation during the transition period enhanced innate immunity parameters and increased milk production in dairy cows.

Effects of rumen-protected choline supplementation on metabolic and performance responses of transition dairy cows.

The objective of this experiment was to compare metabolic and milk production parameters in dairy cows supplemented and nonsupplemented with rumen-protected choline (RPC) during the transition period. Twenty-three nonlactating, multiparous, pregnant Holstein cows were ranked by BW and BCS 21 d before expected date of calving and immediately were assigned to receive (n = 12) or not receive (control; n = 11) RPC until 45 d in milk (DIM). Cows supplemented with RPC received (as-fed basis) 50 and 100 g/d of RPC (18.8% choline) before and after calving, respectively. Before calving, cows were maintained in 2 drylot pens according to treatment with ad libitum access to corn silage, and individually they received (as-fed basis) 3 kg/cow daily of a concentrate. Upon calving, cows were moved to 2 adjacent drylot pens according to treatment, milked twice daily, offered (as-fed basis) 35 kg/cow daily of corn silage, and individually received a concentrate formulated to meet their nutritional requirements after milking. The RPC was individually offered to cows as a topdressing into the morning concentrate feeding. Before calving, cow BW and BCS were recorded weekly, and blood samples were collected every 5 d beginning on d -21 relative to expected calving date. Upon calving and until 45 DIM, BW and BCS were recorded weekly, individual milk production was recorded daily, and milk samples were collected once a week and analyzed for fat, protein, and total solids. Blood samples were collected every other day from 0 to 20 DIM and every 5 d from 20 to 45 DIM. Based on actual calving dates, cows receiving RPC or control began receiving treatments 16.8 ± 1.7 and 17.3 ± 2.0 d before calving, respectively. No treatment effects were detected (P ≥ 0.18) on postpartum concentrate intake, BW and BCS, or serum concentrations of cortisol, ß-hydroxybutyrate, NEFA, glucose, and IGF-I. Cows supplemented with RPC had greater (P ≤ 0.01) mean serum haptoglobin and insulin concentrations compared with control. Cows supplemented with RPC had greater (P < 0.01) milk protein, total solids (P < 0.01), and milk fat concentrations (P = 0.09) compared with control. No treatment effects were detected (P ≥ 0.43) for milk yield parameters, such as fat-corrected or solids-corrected milk yield. In conclusion, supplementing RPC to transition dairy cows increased haptoglobin and insulin concentrations and benefited milk composition.

Effects of excessive energy intake and supplementation with chromium propionate on insulin resistance parameters in nonlactating dairy cows.

The objective was to compare insulin resistance parameters in cows with adequate or excessive energy intake as well as in cows with excessive energy intake receiving Cr supplementation as chromium propionate. Thirteen multiparous, nonlactating Gir × Holstein cows were ranked by BW and BCS and assigned to 1 of 3 dietary treatments on d 0: 1) diet to meet their ME requirements without Cr supplementation (MAN; n = 4), 2) diet to exceed their ME requirements without Cr supplementation (HIGH; n = 4), and 3) HIGH with 2.5 g/d of chromium propionate (HIGHCR; n = 5, with 10 mg of Cr/cow daily). Diets were formulated to provide 100% of daily ME requirements of MAN and 177% of daily ME requirements of HIGH and HIGHCR cows and offered twice daily via individual self-locking head gates from d 0 to 88. Cow BW and BCS were recorded on d 0 and 88 of the experiment. Blood samples were collected before and 2 h after the morning feeding twice weekly. Preprandial revised quantitative insulin sensitivity check index (RQUICKI) was determined using serum glucose, insulin, and NEFA concentrations obtained before feeding. Glucose tolerance tests (GTT) were performed on d 32 and 88 by infusing cows with 0.5 g of glucose/kg of BW whereas blood samples were collected at -15, 0, 10, 20, 30, 45, 60, and 90 min relative to infusion. Change in BCS tended to be greater in HIGH and HIGHCR (P = 0.09) compared with MAN cows. Within samples collected twice weekly, serum concentrations of glucose, insulin (beginning on d 14 of the experiment), and NEFA (preprandial samples only) were greater (P ≤ 0.05) in HIGH compared with HIGHCR cows and tended to be greater in HIGH compared with MAN cows (P ≤ 0.10) but did not differ (P ≥ 0.52) between HIGHCR and MAN cows. Moreover, HIGH cows had reduced RQUICKI compared with MAN (P = 0.02) and HIGHCR cows (P = 0.05) whereas RQUICKI was similar between MAN and HIGHCR cows (P = 0.53). Within samples collected during the GTT, mean serum insulin concentrations and insulin:glucose ratio were greater (P < 0.01) in HIGH compared with HIGHCR cows, tended (P ≤ 0.09) to be greater in HIGH compared with MAN cows, and were similar (P ≥ 0.16) between HIGHCR and MAN cows. Serum glucose concentrations were greater (P < 0.01) for HIGH compared with MAN and HIGHCR cows 20 min relative to infusion. In conclusion, chromium propionate supplementation prevented the increase in insulin resistance caused by excessive energy intake in nonlactating dairy cows.

Podometry: a critical evaluation of its use in Hansen's disease.

The aim of this paper is to evaluate the effectiveness of podometry to measure the pressure developed over the feet and the value of these findings to help in the prevention of the plantar neuropathic ulcer in patients bearing Hansen's disease. We evaluated 13 patients with impaired plantar pain and touch sensations and 17 normal patients. All the patients were submitted to static evaluation using the podometer. The system employed was the "Midcapteur" commercial podometer composed of a platform for acquisition of analogic data capable of registering the segmental pressures applied to the feet. These data are read by a 386 IBM/PC compatible computer that registers the graphic patterns obtained from the pressures developed and also calculates the modes of pressure distribution in the four quadrants of the foot. These data obtained by means of static podometry were compared to the clinical evaluation of pain and touch sensation of the feet in hansenian patients. The results demonstrate that podometery is an efficient method for evaluating the pressure in impaired feet in Hansen's disease and is a progression of neuropathic ulcer; it is sensitive in the identification of the spots of increased pressure in anesthetic and anomalous areas, asymmetries and in correlating the presence of ulcers with increased pressure.