NEFA Concentrations Research Articles

Effect of feeding two types of concentrates in morning and evening meals and two types of fat supplement on diurnal patterns of plasma parameters in lactation dairy cows

The diurnal patterns of feed intake and TMR composition influence blood parameters in dairy cows; however, the effect of feeding TMR with different compositions in the morning and evening meals is not well characterized. In a completely random design, forty Holstein cows (110 ± 30 days postpartum) were randomly assigned to four treatment groups, with 10 cows per treatment. The treatments were as follows: a base diet containing 50 % cereal starch from barley grain and 50 % cereal starch from corn grain in the morning and evening meal + either prilled fatty acids supplement (EqP) or calcium salts of fatty acids supplement (EqCS); a base diet containing 25 % cereal starch from barley grain, 75 % cereal starch from corn grain in the morning meal, and 75 % cereal starch from barley grain and 25 % cereal starch from corn grain in the evening meal + either prilled fatty acids supplement (DiP) or calcium salts of fatty acids supplement (DiCS). Dry matter intake was affected by treatments (P ˂ 0.01). The highest intake was observed for EqP, EqCS, DiP,and DiCS. 3.5 % fat-corrected milk and milk fat percentage was significantly higher for EqP than other treatments (P ˂ 0.01), but other milk components were not significantly different among treatments (P ˃ 0.05). A significant difference was observed for glucose, cholesterol, TG, AST, and insulin concentration among treatments (P ˂ 0.01). The concentrations of all plasma parameters (glucose, cholesterol, TG, BUN, AST, insulin, and NEFA) significantly changed over 24-h period (P ˂ 0.01). Plasma concentrations of glucose, cholesterol, TG, BUN, AST, insulin, and NEFA displayed a treatment-by-time interaction (P ˂ 0.01). In general, changes in the cereal starch ratio (corn and barley) in TMR in each meal during a day affect the 24-h concentration of plasma parameters, but there was no strong evidence of leverage for cows’ metabolism.

Pre- and postpartum metabolizable protein supply: I. Effects on feed intake, lactation performance, and metabolic markers in transition dairy cows.

The objective of this study was to investigate the effect of increasing MP supply in the prepartum, postpartum, or both diets on intake, performance, and metabolic indicators. Multiparous Holstein cows (n = 96) were assigned to 1 of 4 treatment groups at 28 d before expected calving following a randomized block design. Prepartum diets were formulated to contain either a control (C; 85 g of MP/kg DM) or high (H; 113 g of MP/kg DM) level of estimated MP. From calving to 21 DIM, diets were formulated to contain either a control (C; 104 g of MP/kg DM) or high (H; 131 g of MP/kg DM) level of estimated MP. To control the potential confounding effect of Met and Lys supply, diets were formulated to supply an equal amount at 1.24 and 3.84 g/Mcal of ME in both prepartum diets and 1.15 and 3.16 g/Mcal of ME in both postpartum diets, respectively. The combination of a pre- and postpartum diet resulted in 4 treatment groups: 1) CC (n = 23), 2) CH (n = 24), 3) HC (n = 22), and 4) HH (n = 23). A common lactation diet (113 g of MP/kg DM) was fed from 22 DIM to the end of the observation period at 42 DIM. Milk yield and DMI were collected daily, and plasma metabolic indicators (BHB, fatty acids [NEFA], urea nitrogen [PUN], and glucose) were determined twice weekly from -28 to 28 d relative to calving and once weekly from 29 to 42 DIM. Samples with BHB ≥1.2 mmol/L between 3 and 10 DIM were considered hyperketonemia events. Milk composition was determined weekly. Milk yield during 1 to 21 DIM was greater in HH (44.7 ± 1.0 kg/d) compared with CC (39.2 ± 1.0 kg/d) and HC (38.0 ± 1.0 kg/d) and milk yield in CH (42.4 ± 0.9 kg/d) was greater than HC, respectively. From 22 to 42 DIM, milk yield was greater in CH (53.3 ± 1.0 kg/d) and HH (54.1 ± 1.0 kg/d) compared with CC (49.6 ± 1.0 kg/d) and HC (49.3 ± 1.0 kg/d). Dry matter intake (% of BW) and concentrations of milk protein, fat, and total solids were not affected by treatment. Prepartum concentrations of PUN were greater in H compared with C. From 1 to 21 DIM, PUN concentrations were greater in CH and HH compared with CC and HC. From 1 to 21 DIM, glucose concentrations were lower in HH compared with HC and BHB were greater in CH and HH compared with HC. Concentrations of NEFA, as well as the number of hyperketonemia events did not differ by treatment during this time. From 22 to 42 DIM, concentrations of NEFA were greater in HH compared with HC and concentrations of BHB were greater in CH and HH compared with HC. Overall, feeding CH or HH increased lactation performance without altering intake or hyperketonemia events. Results from this study support formulating a fresh diet to reduce the negative MP balance during early lactation.

402 The effect of supplemental protein degradability and frequency of supplementation on nitrogen metabolism of beef cattle consuming low-quality forage

Abstract Rumen degradable protein (RDP) is required for cattle consuming low-quality forage to ensure adequate fiber digestion. However, in situations where cattle are not supplemented daily, supplementing RDP could overwhelm the nitrogen recycling mechanisms, leading to increased nitrogen excretion. The objective of this experiment was to determine the effect of rumen degradability and frequency of supplemental protein in beef cattle consuming low-quality forage. Treatments were arranged in a 2 × 2 factorial with protein degradability (68.5% or 32.8% RDP) and supplementation frequency (daily or biweekly) as the two factors. Ruminally cannulated Angus steers [n = 8; body weight (BW) = 328 ± 12.2 kg] were used in a Latin rectangle. The low RDP treatment was composed of 50% soybean hulls and 50% corn gluten meal (40.3% CP; 32.8% RDP), and the high RDP treatment consisted of 45.4% soybean hulls, 41.4% soybean meal, 4.1% urea, and 9.1% molasses (40% CP; 68.5% RDP). The biweekly steers were supplemented on d 0, 4, 7, 11, 14, 18, and 21 of each period. Steers were given ad libitum access to low-quality (7.4% CP) native grass hay. Daily blood samples were collected from d 14 to 17 at 0630 h and d 21 at -2, 3, and 7 h relative to supplementation. Rumen fluid samples were collected every 4 h on d 18 to 21. Daily NEFA concentrations decreased (P < 0.001) post-supplementation in the biweekly supplemented steers and then returned to baseline values, while the daily supplemented steers had no change. Hourly NEFA concentrations in steers supplemented with high RDP biweekly increased from 2 h pre-supplementation to 3 h post-supplementation (P < 0.001), then decreased at 7 h post-supplementation back to pre-supplementation concentrations. Plasma urea nitrogen (PUN) increased in biweekly high RDP supplemented steers 1 d after supplementation (P < 0.001) and decreased from d 15 to d 17. PUN concentrations increased from 2 h pre-supplementation through 7 h post-supplementation in both high RDP treatments, while low RDP treatments did not change (P < 0.001). Rumen fluid lactate and ammonia concentrations rapidly increased in the biweekly high RDP-supplemented steers in response to each supplementation (P < 0.001). There were spikes in ammonia concentrations for the daily high RDP treatment post-supplementation; however, they were smaller in magnitude compared with the biweekly high RDP. The low RDP treatments remained steady across all hours of ammonia sampling, where daily and biweekly supplemented steers decreased slightly in the time points following supplementation and then gradually increased. Rumen pH displayed drastic changes in the biweekly high RDP-supplemented group with values ranging from 6.99 to 5.97 (P < 0.001), but the low RDP treatments remained consistent. Supplementing biweekly with high RDP resulted in fluctuations in metabolites not observed in the other treatments, which could reduce forage utilization and increase nitrogen excretion.

140 Effects of ɷ-3 PUFA supplementation during late gestation to first-calf beef heifers on physiological and performance responses of offspring

Abstract The objectives of this experiment were to evaluate the effects of ɷ-3 PUFA supplementation to late gestation first-calf beef heifers on milk and immunoglobulin production and performance and physiological responses of the offspring. Non-lactating, pregnant Angus heifers (n = 44) were ranked by age, body weight (BW), and body condition score (BCS) and allocated to receive DDG + 1 of the 2 treatments: 1) 234 g/heifer per feeding of Ca salts of PUFA based on eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids (OMG, Strata; Virtus Nutrition LLC, Corcoran, CA; n = 22), 2) 234 g/heifer per feeding of Ca salts of saturated and monosaturated fatty acids based on palmitic and oleic acids (CON; EnerGII, Virtus Nutrition, LLC; n = 22; Table 1). The animals were gathered each week on Mondays, Wednesdays, and Fridays and individually fed DDG + treatments. Immediately after calving, heifer-calf pairs were removed from their respective treatments and assigned to the general management of the research herd until weaning, which did not include fatty acid supplementation. Calves were transported to a feedyard for a 90-d preconditioning and feedlot receiving period. Initial cow BW and BCS were similar (P ≥ 0.49) among treatments. No differences were also detected (P ≥ 0.33) for BW or BCS change, and at calving BW or BCS (Table 3). No differences were observed between groups for average colostrum composition (P > 0.37). However, there was an increase in colostrum fat percentage (P = 0.03) and a tendency of greater concentration of colostrum IgG (P = 0.08) in OMG heifers compared with the control group. No significant differences were observed among treatments at calving results (P > 0.83; Table 3). However, a tendency was observed for crown to rump measure (P = 0.07). During the preconditioning period, there was a difference among groups for final BW (P = 0.04) and average daily gain (ADG; P = 0.05), remaining throughout the receiving phase among treatments for initial BW (P = 0.04), final BW (P = 0.04) and ADG (P = 0.05). A tendency (P = 0.09) for greater NEFA concentration and greater cortisol concentrations (P = 0.05) was observed in OMG vs. CON cohorts (Table 4, Table 5). Supplementation during late gestating first-calf beef heifers yielded similar outcomes on cow and offspring performance from birth to weaning; however, OMG calves were 6 kg heavier when compared with CON after being fed a high-energy feedlot diet, meaning that ɷ-3 PUFAs supplemented during late gestation might be an alternative to optimize feedlot responses of the offspring.

The Effect of Different Forms of Solid Feed on Biochemical Parameters in Blood Plasma of Calves

Abstract The study examined how different solid feeds affected the biochemical parameters in calf plasma. The experiment involved a control group and three test groups of calves, each fed with a different starter mixture. The results showed significant differences in some biochemical parameters between the feeding groups. Calves in groups P1 and P3 had a statistically higher glucose concentration in blood plasma compared to group C. Calves from group P3 had a higher concentration of urea in blood plasma than calves from group C. Calves in groups P1 and P3 also had higher concentrations of total protein and globulin in blood plasma compared to group C. The concentration of inorganic phosphate in the blood plasma of calves from group P3 was significantly higher than that of group C. Female calves in the experimental groups showed a lower concentration of NEFA at three months of age compared to the control group. It was concluded that feeding calves with a starter mixture containing whey and easily digestible protein had a positive effect on the nutritional status and energy balance of the calves.

Dynamic Changes in the Nutrient Digestibility, Rumen Fermentation, Serum Parameters of Perinatal Ewes and Their Relationship with Rumen Microbiota.

Changes in physiological and biochemical parameters are crucial for the reproductive performance and health of perinatal ewes. This study investigated the temporal variations in feed intake, nutrient digestibility, serum parameters, and ruminal fermentation on days 21, 14, and 7 before lambing (Q21, Q14, and Q7) and days 3, 7, and 14 after lambing (H3, H7, and H14). The results showed that dry matter intake (DMI) and glucose (Glu) gradually decreased (p < 0.05) before lambing and increased (p < 0.05) after lambing. The digestibility of dry matter (DMD), crude protein (CPD), and acid detergent fiber (ADFD) increased (p < 0.05) before lambing, then decreased (p < 0.05) on day H3, and then increased (p < 0.05) on day H14. The rumen pH, NH3-N, and triglycerides (TG) gradually increased (p < 0.05) before lambing and were higher (p < 0.05) on day Q7 than after lambing. The concentrations of acetate, butyrate, and total volatile fatty acids (T-VFA) were lower (p < 0.05) on day Q7 than those on days Q21 and Q14, then increased (p < 0.05) after lambing. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) concentrations gradually decreased (p < 0.05) in perinatal ewes. BHBA and NEFA concentrations were lower (p < 0.05) on day Q21 than those from days Q14 to H14. The rumen microbiota compositions were different (p < 0.05) in perinatal ewes, and g_Anaerovibrio, g_Lachnobacterium, and g_Schwartzia were positively correlated (p < 0.05) with DMI, Glu, acetate, propionate, and T-VFA, and negatively correlated (p < 0.05) with LDL-C. g_Bacillus was negatively correlated (p < 0.05) with DMI, Glu, acetate, propionate, butyrate, and T-VFA, but positively correlated (p < 0.05) with rumen pH and LDL-C. In summary, the DMI, nutrient digestibility, rumen fermentation, and serum parameters changed during the perinatal period of ewes, and the changes in DMI, serum glucose, acetate, propionate, and T-VFA were related to the rumen bacteria.

Effects of rate of body weight gain during the first trimester of gestation on beef heifer and offspring performance, concentrations of hormones and metabolites, and response to vaccination.

Our study objectives were to evaluate the effects of divergent rates of body weight (BW) gain during early gestation in beef heifers on F0 performance, metabolic and endocrine status, colostrum immunoglobulins, and subsequent F1 calf characteristics, growth performance, concentrations of hormones and metabolites, and response to vaccination. Angus-based heifers (n = 100; BW = 369 ± 2.5kg) were adapted to individual feeding for 14 d and bred using artificial insemination with female-sexed semen. Heifers were ranked by BW assigned to either a basal diet targeting 0.28kg/d gain (LG, n = 50) or the basal diet plus an energy/protein supplement targeting 0.79kg/d gain (MG, n = 50) until d 84 of gestation. Dam BW and blood samples were collected at 6 time points during gestation; body composition was evaluated at d -10 and 84; and fetal measurements were taken on d 42, 63, and 84. At calving (LG, n = 23; MG, n = 23), dam and calf BW were recorded; and colostrum, calf body measurements, and blood samples were collected. Cow-calf pairs were managed on a common diet from calving to weaning, followed by a common postnatal development period for all F1 female offspring. Growth performance, hormone and metabolite profiles, feeding behavior, and reproductive performance were assessed from birth to pre-breeding in F1 heifers. Offspring were vaccinated against respiratory disease and bovine viral diarrhea pathogens on d 62.3 ± 4.13 and 220.3 ± 4.13 post-calving. By design, MG dams were heavier (P < 0.0001) than LG at d 84, and the BW advantage persisted until subsequent weaning of F1 calves. Concentrations of serum IGF-1 and glucose were increased throughout gestation (P < 0.001) for MG dams, whereas concentrations of NEFA were decreased (P < 0.001) in LG dams. Calves from MG dams were 2.14kg heavier (P = 0.03) and had larger chest circumference (P = 0.04) at birth compared with LG cohorts. Heifers from MG dams continued to have greater (P ≤ 0.03) BW gain and feed efficiency during the development period, but no differences were observed (P ≥ 0.13) in body composition, concentrations of hormones and metabolites, feeding behavior, puberty attainment, and response to vaccination in F1 offspring. Hence, early gestation rate of gain impacted BW and concentrations of glucose and IGF-1 throughout gestation in the F0 dam, resulting in altered F1 calf BW and measurements at birth and increased gain and efficiency during the development period.

Estimations of prepartum feed intake and its effects on transition metabolism and subsequent milk production

The objectives of this study were to identify factors associated with prepartum DMI, evaluate the performance of linear models to estimate prepartum DMI using different classes of predictors, and investigate the consequences of different levels of prepartum DMI on transition metabolism and lactation performance. Individual feed intake of nulliparous (n = 100) and parous cows (n = 173) was measured by automatic feeding bins from d -35 to 98 relative to calving. Rumination and physical activities were monitored by wearable sensors. Blood metabolites were measured on d -21, -10, -3, 0, 3, 7, 10, 14, and 21. Body weight (BW) and body condition score (BCS) were assessed throughout the study. The average prepartum DMI as percentage of BW (DMIpBW) was calculated for each cow and used as dependent variable of linear models. Parity, prepartum BCS and BW, milk production in the previous lactation (M305) and at dry-off (MYDO), and length of the dry period were associated with DMIpBW and explained 41% of the variation in all cows, and 49% in parous cows. Estimations of DMIpBW were improved when data on prepartum rumination and blood metabolites were added in the predictive models. In the latter, the adjusted R-Sq increased to values between 47 and 61%, and selected models performed consistently in a 5-fold cross-validation analysis. To evaluate the implications of DMIpBW to transition metabolism and performance, cows were ranked within parity and classified into terciles as low (LFI), moderate (MFI), or high feed intake (HFI). The mean DMI was 1.44, 1.70, and 1.91 ± 0.01% of BW, respectively. No differences in BW were observed in nulliparous cows, but all 3 groups of parous cows differed (LFI = 892, MFI = 849, HFI = 798 ± 8 kg). The proportion of cows with BCS > 3.5 at enrollment differed among all groups, and averaged 67.4, 55.1, and 36.5 ± 6%, respectively. For parous cows, M305 and MYDO differed among all groups and averaged 9,808, 10,457, and 11,182 ± 233 kg, and 18.1, 23.1, and 26.2 ± 1 kg/d, respectively. After calving, DMI (LFI = 20.9, MFI = 21.9, and HFI = 22.1 ± 0.2 kg/d) and milk yield (LFI = 36.7, MFI = 38.2, and HFI = 38.3 ± 0.4 kg/d) was lower in LFI cows compared with the other 2 groups. Postpartum EBAL differed among all groups and averaged -2.79, -1.63, and -0.66 ± 0.3 Mcal/d for LFI, MFI, and HFI, respectively. During the transition period, LFI cows had higher serum concentrations of NEFA, BHB, Cl (prepartum only), and AST (postpartum only), and lower serum concentrations of cholesterol, P, GLDH, GGT (prepartum only), AST (prepartum only), urea (parous only), and SOD activity (parous only). In conclusion, a low level of prepartum DMI was associated with fatter and heavier cows, lower milk production in previous lactation, important adjustments in energy metabolism, and moderate losses in DMI and milk yield in the subsequent lactation. Moreover, the inclusion of prepartum rumination activity and target blood metabolites into predictive models improved the estimations of prepartum DMI.

Effects of propylene glycol in different doses on metabolic parameters in dairy cows

In the study, the effects of propylene glycol (PG) drenched in different doses in dairy cows with positive energy balance were evaluated on serum metabolic parameters. Twenty-four Simmental dairy cows in 60-190 days of lactation period with positive energy balance were included to this study. PG was drenched 3 h after morning feeding, at a doses of 300 mL (8 dairy cows) and 500 mL (8 dairy cows), once a day, for 3 days. Eight dairy cows were included for control group. Blood samples were collected once before PG drenching, daily after drenching of PG, and finally on day 4. Serum biochemical parameters were determined. With regard to energy metabolism, glucose concentrations from serum biochemical parameters significantly increased on day 3 in 500 mL PG group compared to control group, and there were not significant changes in BHBA and NEFA concentrations. Decreased urea, increased chloride concentrations were determined with within reference limits. In dairy cows with positive energy balance, 500 mL PG oral drenching had positive effect on energy balance as determined by serum glucose measurements, might not have negative effects on hepatic and renal function, and may cause serum electrolyte changes within reference limits.

The use of ultrasonography in the transition period to estimate adipose tissue depots and their association with risk of early postpartum hyperketonemia in Holstein dairy cattle

An elevated prepartum BCS is a risk factor for postpartum hyperketonemia (HYK) and elevated fatty acid (NEFA) concentrations in dairy cattle. The association between different adipose tissue depots, such as subcutaneous (SCAT) as well as visceral adipose tissue (VAT) depots and HYK and elevated NEFA concentrations remains unknown. The objective of this 2-part study was to describe SCAT and VAT depots using ultrasonography during the transition period and to associate them with metabolic markers of negative energy balance in early postpartum dairy cows. Multiparous Holstein cows were enrolled in a prospective observational cohort study with 2 cohorts in subsequent study years (Cohort 1: n = 31; Cohort 2: n = 28). At −6, −4, −2, and 2 wk relative to calving (Cohort 1) or −2 and 2 wk relative to calving (Cohort 2) BCS was determined and cows were examined via transcutaneous ultrasound at 6 locations for prediction of adipose tissue mass in 5 depots: 1) abdominal adipose tissue (AAT), 2) retroperitoneal adipose tissue (RPAT), 3) omental adipose tissue (OMAT), 4) mesenteric adipose tissue (MAT), and 5) subcutaneous adipose tissue (SCAT). Postpartum serum NEFA and BHB concentrations were determined twice weekly from 1 to 14 DIM. Cows were categorized as having HYK or high NEFA concentrations (NEFAH) if ≥1 sample resulted in a BHB ≥1.2 mmol/L or NEFA ≥720 µEq/L, respectively. Critical thresholds associated with HYK or NEFAH for each depot at −2 wk relative to calving and the time of maximum estimated depot size were evaluated using logistic regression and a receiver operator characteristic analysis. Abdominal AT increased from −6 to −2 wk relative to calving in cohort 1 but did not differ from −2 to 2 wk relative to calving. Subcutaneous AT did not change from −6 to −2 wk but decreased from −2 to 2 wk relative to calving in cohort 1 and 2. Omental AT accurately (AUC = 0.77) predicted HYK in cohort 1 but was non-informative for the prediction of HYK in cohort 2 (AUC = 0.49). Predicted AT depots were not informative for the prediction of NEFAH (AUC ≤0.59) in either cohort. Results from this study suggest that AT can be monitored during the transition period using the described technique; however, estimated prepartum AT depots at −2 wk relative to expected calving were inaccurate in distinguishing between postpartum NEFAH and non-NEFAH or HYK and non-HYK.

Systemic inflammation in early lactation and its relation to the cows' oxidative and metabolic status, productive and reproductive performance, and activity

A dysregulated inflammatory response contributes to the occurrence of disorders in cows during the transition period from pregnancy to lactation. However, a detailed characterization of clinically healthy cows that exhibit an enhanced inflammatory response during this critical period remains incomplete. In this experiment, a total of 99 individual transition dairy cows and 109 observations (18 cows monitored in 2 consecutive lactations), submitted to similar transition management were involved to evaluate the relationship between elevated an inflammatory response and metabolic and oxidative status, as well as transition outcomes. Blood was taken at -7, 3, 6, 9, and 21 DIM, and concentrations of metabolic parameters (glucose, β-hydroxybutyric acid, nonesterified fatty acids [NEFA], insulin, IGF-1, and fructosamine) were analyzed. Additionally, oxidative parameters (proportion of oxidized glutathione to total glutathione in red blood cells, the activity of glutathione peroxidase [GPx] and superoxide dismutase, concentrations of malondialdehyde, and oxygen radical absorbance capacity) and acute phase proteins (APP) including haptoglobin (Hp), serum amyloid A (SAA) and albumin-to-globulin ratio (A:G) were determined in the blood at 21 DIM. The 3 APP parameters were used to group clinically healthy cows into 2 categories through k-medoids clustering (i.e., a group showing an acute phase response, APR; n = 39) and a group not showing such a response (i.e., non-APR; n = 50). Diseased cases (n = 20) were handled in a separate group. Lower SAA and Hp concentrations as well as higher A:G were observed in the non-APR group, although for Hp, differences were observed from the APR group and not from the diseased group. Only 1 of the 5 oxidative parameters differed between the groups, with the non-APR group exhibiting lower GPx activity compared with the diseased group. The non-APR group showed the highest IGF-1 levels among the 3 groups and and lower NEFA concentrations compared with the diseased groups. Cows in the diseased group also showed reduced dry matter intake and milk yield compared with clinically healthy cows, regardless of their inflammatory status. Moreover, the APR group exhibited temporarily lower activity levels compared with the non-APR group. These findings highlight that cows with a lower inflammatory status after 21 DIM exhibited better metabolic health characteristics and productive performance, as well as activity levels. Nevertheless, the detrimental effects of a higher inflammatory status in the absence of clinical symptoms are still relatively limited.

Social rank affects the endocrine response to frequent regroupings in grazing dairy heifers

The objectives of this study were to determine the social behavior response to repeated social regrouping (SR), and if social rank and the changes of social rank affect the growth rate and some metabolites and hormones linked to energy status, in “resident” replacement dairy heifers subjected to SR for 205 d. Fourteen dairy heifers (153.3 ± 16.1 kg; 9 to 11 mo old), maintained under grazing conditions, were regrouped every 21 d with 5 new animals (total = 10 SR). Two days after each SR, heifers were weighed and their withers height was measured, and blood samples for nonesterified fatty acids, glucose, and IGF-1 were taken. Concentrations of nonesterified fatty acids, glucose, and IGF-1 were taken. Social behavior was registered by continuous sampling and social status was calculated by the ETlog software, considering the total number of agonistic interactions on 2 d before and 7 d after each SR. A dominance scale was constructed in each SR, and heifers were categorized as high-ranked (HRA), medium-ranked (MRA), and low-ranked (LRA). In addition, the social rank in the first and the last 5 SR were compared, resulting in 3 categories: heifers that remained in the same social rank (Mai), and heifers that lowered (Low) and raised (Rai) their social ranks. Variables were analyzed by repeated measures using a generalized lineal mixed model, considering the social rank in each SR or the change in social rank, the number of SR and their interaction as main effects, and the farm of origin and animal as random effects. Heifers performed more agonistic (2.6 vs. 1.8 ± 0.6, day of SR and 7 d later, respectively) and total (3.8 ± 1.2 vs. 2.5 ± 0.7, day of SR and 7 d later, respectively) interactions on the day of each SR than 7 d after, whereas the number of interactions decreased after the first 2 SR. Medium-ranked heifers presented greater IGF-1 concentrations than HRA heifers at SR1, SR4, and SR9, and than LRA heifers at SR3 and SR4, whereas IGF-1 concentrations were greater in HRA heifers than MRA heifers at SR3 and SR7. In addition, LRA heifers had greater IGF-1 concentrations than MRA ones at SR3 and compared with HRA heifers at SR9. Heifers that lowered their social had greater IGF-1 concentrations than Mai heifers along the SR (132.5 ± 17.1 vs. 97.8 ± 11.2 ng/mL, Low and Mai heifers, respectively) and at SR1, SR3, and SR9. In conclusion, although regrouping animals according to their characteristics can facilitate farm handling, it should be considered that endocrine profile may be affected according to heifers' position in the social hierarchy.

Investigation of Adiponectin, Leptin and Ghrelin Levels and Evaluation of Metabolic Profiles in the Periparturient Period in Romanov Sheep

The periparturient period is very important especially in terms of pregnancy-related herd-based diseases. In this period, especially for early diagnosis of subclinical diseases, a metabolic profile test is used. In the periparturient period, important changes occur in adipose tissue. Blood samples were collected from 16 Romanov sheep in the periparturient in serum tubes on the 21st, 14th, 7th, and postpartum days, and 7th, 14th, and 21st days after delivery. Metabolic profile and Adiponectin, Leptin and Ghrelin parameters evaluated from the blood samples. In the periparturient period, ELISA analyzes of TNF-α were performed for inflammatory evaluation. As a result of the analyzes, Prenatal increase in NEFA concentrations, postpartum decrease in cholesterol concentrations, postpartum increase and decrease in AST concentrations, postpartum increase in GGT concentrations, prenatal and postnatal increases in total protein concentrations, postpartum increase in BUN and creatinine concentrations, postpartum decrease in magnesium concentrations, Prenatal increase in adiponectin concentrations and postpartum decrease, postpartum decrease in leptin concentrations and prenatal increase in ghrelin concentrations occurred. With the results obtained, it was concluded that the evaluation of metabolic profile and adipose tissue is important in the diagnosis of diseases in the periparturient period.

Monitoring mammary gland development in preweaned dairy heifers using ultrasound imaging

Existing literature on the long-term effects of nutritional manipulation on milk production is incomplete and inconsistent as animals are typically culled before lactation. In addition, longitudinal studies are rarely conducted due to high costs and constraints related to tissue sampling; therefore, additional research is necessary to better understand the effect of early nutrition and growth on subsequent growth and milk production. Thirty Holstein heifer calves were pair-fed high (H; 22% crude protein and 15% fat) or low (L; 27% crude protein and 20% fat) milk replacers. Mammary gland ultrasound images and body weights were collected twice weekly, and blood samples weekly, for the first 8 weeks of life. Calves fed H had higher average daily gain (ADG) and mammary gland growth through 8 weeks of life. Calves from the H group also had larger fat pads at 8 weeks of age. Glucose and insulin concentrations were increased in H calves compared with L calves, whereas NEFA concentrations were not different between treatments. Our results suggest that ultrasound is a practical, noninvasive tool to monitor udder development preweaning, although additional research is necessary to improve image analysis techniques to analyze tissue composition. Our preliminary work provides data suggesting that the use of mammary gland ultrasound could provide a method of longitudinal analysis of the effects of preweaning nutrition on milk production.

Use of rumination time in health risk assessment of prepartum dairy cows

The objectives of this observational cohort study were to evaluate the associations of rumination time (RT) in the last week of pregnancy with transition cow metabolism, inflammation, health, and subsequent milk production, reproduction, and culling. Pregnant nulliparous (n = 199) and parous (n = 337) cows were enrolled 21 d before the expected calving. RT and physical activity were monitored automatically by sensors from d -21 to 15 relative to calving. Blood samples were collected on d -14, -5, 4, 8, and 12 ± 1 relative to calving. Diagnoses of clinical health problems were performed by researchers from calving to 15 d in milk (DIM). In classification 1, cows were ranked based on average daily RT in the last week of pregnancy and classified into terciles as short RT (SRT), moderate RT (MRT), or long RT (LRT) for association analyses. In classification 2, RT deviation from the parity average was used in a receiver operating characteristic curve to identify the best threshold to predict postpartum clinical disease. Cows were then classified as above the threshold (AT) or below the threshold (BT). Compared with cows with LRT, cows with SRT had greater serum concentrations of NEFA (0.47 vs 0.40 ± 0.01 mmol/L), BHB (0.58 vs 0.52 ± 0.01 mmol/L), and haptoglobin (0.22 vs 0.18 ± 0.008 g/L) throughout the transition period, and reduced concentrations of glucose, cholesterol, albumin, and magnesium in a time-dependent manner. Parous cows with SRT had higher odds of postpartum clinical disease (adjusted odds ratio [AOR]: 3.7; 95% confidence interval [CI]: 2.1-6.4), lower odds of pregnancy by 210 DIM (AOR: 0.34; CI: 0.15-0.75), and lower milk production (46.9 vs 48.6 ± 0.5 kg/d) than parous cows with LRT. Deviation in prepartum RT had good predictive value for clinical disease in parous cows (area under the curve [AUC]: 0.65; CI: 0.60-0.71) but not in nulliparous (AUC: 0.51; CI: 0.42-0.59). Separation of parous cows according to the identified threshold (≤-53 min from the parity average) resulted in differences in serum concentrations of NEFA (AT = 0.31 ± 0.006, BT = 0.38 ± 0.014 mmol/L), BHB (AT = 0.49 ± 0.008, BT = 0.53 ± 0.015 mmol/L), and globulin (AT = 32.3 ± 0.3, BT = 34.8 ± 0.5 g/L) throughout the transition period, as well as in serum cholesterol, urea, magnesium, albumin, and haptoglobin in a time-dependent manner. BT parous cows had higher odds of clinical disease (AOR: 3.7; CI: 2.1-6.4), reduced hazard of pregnancy (AHR: 0.64, CI: 0.47-0.89), greater hazard of culling (AHR: 2.1, CI: 1.2-3.6), and lower milk production (46.3 ± 0.7 vs 48.5 ± 0.3 kg/d). External validation using data from 153 parous cows from a different herd and the established threshold in RT deviation (≤-53 min) resulted in similar predictive value, with the odds of postpartum disease 2.4 times greater in BT than AT (37.5 vs 20.1%). In conclusion, RT in the wk preceding calving was a reasonable predictor of postpartum health and future milk production, reproduction, and culling in parous cows but not in nulliparous cows.

Biochemical profile and oocyte quality of primiparous Bos indicus cows submitted to a timed artificial insemination protocol

The objective of this study was to verify the causes of the lower response of primiparous Bos indicus cows to the ovulation synchronization protocol. Two experiments were performed to evaluate the biochemical profile, oocyte and follicular cell quality (Experiment 1) and pregnancy (Experiment 2). In Experiment 1, suckled primiparous (n = 24) and multiparous cows (n = 24) were submitted to ovum pick up (OPU). On Day 0 (D0), all cows received 2 mg of estradiol benzoate (EB) and an intravaginal progesterone insert (P4). Five days (D5) after the first hormonal administration (EB + P4), all follicles larger than 3 mm were counted on each ovary, and ovum pick-up (OPU) was performed. On day 12 (D12), the intravaginal progesterone insert was removed, and measurement and aspiration of the largest follicle were performed. Blood samples were collected on D5 and D12 to evaluate the concentrations of glucose, cholesterol, NEFA, IGF-1 and insulin. In Experiment 2, suckled primiparous (n = 50) and multiparous (n = 50) cows were subjected to an ovulation synchronization protocol based on E2/P4 (D0: 2 mg EB plus P4 intravaginal insert; D8: 500 μg of cloprostenol, 1 mg cypionate estradiol and 300UI of eCG; D10: artificial insemination). In addition, blood samples were collected on D10 for evaluation of the same hormones and metabolites described in Experiment 1. In all studies, calves remained with the cows during the experimental period. In experiment 1, the number of oocytes grade 1 (P = 0.83), grade 2 (P = 0.23) and grade 3 (P = 0.51), total number of retrieved oocytes (P = 0.14), oocyte quality index (P = 0.93) and total viable oocytes (P = 0.38) did not differ between primiparous and multiparous cows. The number of follicles at the time of follicular aspiration (20.7 ± 1.5 vs. 18.0 ± 1.9; P = 0.05) and the diameter of the largest follicle on D12 (13.5 ± 0.6 vs. 11.4 ± 0.6; P = 0.04) were greater in multiparous cows, and the number of degenerated oocytes was greater in primiparous cows (1.9 ± 0.7 vs. 1.2 ± 0.3; P = 0.05). On D5, the concentrations of IGF-1 (P = 0.47), insulin (P = 0.08), total cholesterol (P = 0.47), NEFA (P = 0.77) and glucose (P = 0.55) in the blood and IGF-1 (P = 0.97) and insulin (P = 0.11) in the follicular fluid did not differ between parity groups. On D12, there was no difference in the concentrations of IGF-1 (P = 0.26), total cholesterol (P = 0.32), NEFAs (P = 0.31) and glucose (P = 0.93) in the blood between primiparous and multiparous cows, however, the serum insulin concentration (P = 0.04) was higher in primiparous cows. There was no correlation between serum and follicular fluid insulin concentrations (r = 0.17; P = 0.31), however, there was a low correlation between serum and follicular fluid IGF-1 concentrations (r = 0.47; P = 0.002). Quantification of transcripts did not differ between parity groups. In experiment 2, concentrations of NEFA (P = 0.12) and insulin (P = 0.16) in the blood and P/AI (P = 0.93) did not differ between parity [60 % (30/50) primiparous vs. 60 % (30/50) multiparous]. In contrast, blood concentrations of IGF-1 (P = 0.0001), total cholesterol (P = 0.005) and glucose (P = 0.01) were greater in primiparous cows. It was concluded that the oocyte quality and expression of the genes evaluated in the granulosa cells were not different between primiparous and multiparous cows. Unexpectedly, the pregnancy rate did not differ between parity. Nevertheless, the blood concentrations of IGF-1, total cholesterol and glucose were greater in primiparous cows.

Effect of Gracilaria vermiculophylla Macroalga on Non-Alcoholic Fatty Liver Disease in Obese Rats.

Marine algae are valuable sources of bioactive compounds that have the potential to be used in the management of various pathologies. Despite the increasing prevalence of NAFLD, the absence of an approved effective pharmacological treatment with demonstrable effectiveness persists. In this context, the aim of the present study is to assess the effect of Gracilaria vermiculophylla red seaweed dietary supplementation on hepatic lipid accumulation, as well as on oxidative stress, inflammation and fibrosis- related markers on obese fa/fa Zucker rats fed with a standard diet, supplemented or not with 2.5% or 5% dehydrated Gracilaria vermiculophylla. After a six-week supplementation with the macroalga, no significant reduction in hepatic total lipid content or hepatic triglyceride content was observed. However, both doses were able to diminish hepatic NEFA concentration by reducing de novo lipogenesis and increasing mitochondrial biogenesis. Moreover, supplementation with the dose of 2.5% improved some oxidative stress and inflammation-related markers. Supplementation with the dose of 5% did not exert these clear beneficial effects. Thus, this study demonstrates that while Gracilaria vermiculophylla may not mitigate hepatic steatosis, it could exert protective effects on the liver by reducing NEFA content and enhancing oxidative stress and inflammation parameters.

Investigating nutritional strategies during a rest period to improve health, growth, and behavioral outcomes of transported surplus dairy calves

The objective of this study was to investigate the effects of feeding surplus dairy calves a milk replacer (MR) or one of 2 different oral rehydration solutions (ORS) during a mid-transportation rest period on metabolic and clinical health indicators, growth, and behavioral outcomes after arrival to a calf-raising facility. Surplus dairy calves (n = 128) were transported in 4 cohorts from February to July 2022 for 12 h to a holding facility, rested for 8 h, then transported for an additional 6 h to a calf-raising facility. Upon arrival to the holding facility, calves were randomly assigned to 1 of 3 treatments: MR (n = 43), a high sodium ORS developed for diarrhea (ORS-D; n = 43), or a high potassium ORS developed for transportation (ORS-T; n = 42). The exact age of calves at transportation was unknown, however all calves were under 14 d of age. Calf body weight at enrollment was 43.9 ± 5.9 kg, 43.7 ± 6.5 kg, and 45.0 ± 4.5 kg for calves fed MR, ORS-D, and ORS-T, respectively. Calves were fed 2.0 L of their treatment twice, once upon arrival and once before leaving the holding facility. At unloading and reloading at the holding facility, calves were weighed and blood sampled. Calves were also health scored at unloading at the holding facility. After arrival at the calf-raising facility, calves were weighed, health scored, and blood sampled. Blood samples were collected at 24 and 48 h and body weight (BW) was recorded at 24 h, 48 h, 72 h, 5 d, 7 d, 14 d, and at 8 wks after arrival to the calf-raising facility. Calves were also health scored daily for 14 d, which included fecal consistency scoring and evaluating the presence or absence of respiratory disease. Lying time, lying bouts, and activity index were measured during transportation and from 3 d relative to transportation using accelerometers. At arrival to the calf-raiser, calves fed ORS-D had higher concentrations of NEFA and BHB than calves fed MR. Furthermore, calves fed ORS-T had higher concentrations of BHB at arrival to the calf raiser compared with calves fed MR. In the 14 d after arrival to the calf-raiser, there was evidence that calves fed ORS-T had a higher proportion of days with diarrhea and respiratory disease compared with those fed MR. During transportation, calves fed ORS-T had a lower activity index than calves fed MR, suggesting that ORS-T calves had lower overall activity. Additionally, on the day of transportation (d 0), ORS-T and ORS-D calves had a lower activity index than calves fed MR. There were no treatment effects on growth outcomes. The results of this study suggest that feeding MR rather than an ORS during a mid-transportation rest period could minimize fat mobilization and can potentially improve diarrhea and respiratory disease but does not affect growth outcomes after arrival to calf-raisers.

Multiple administrations of bovine-appeasing substance during a 42-d preconditioning program followed by feedlot receiving and its effects on physiologic, health, and performance responses of feeder cattle.

This experiment evaluated the effects of multiple bovine-appeasing substance (BAS) administration during a 42-d preconditioning program followed by a feedlot receiving period on productivity, health, and physiological variables of feeder cattle. Ninety calves were weaned, weighed, loaded into a livestock trailer, transported for 70 km, and unloaded at the Bozeman Agricultural Research and Teaching Farm for a 42-d preconditioning program. Upon arrival, calf body weight (BW) was recorded again, and both pre- and post-transport BWs were averaged and used as calf weaning initial BW. Calves were ranked by BW, sex, and age in a completely randomized design and assigned to receive 1) multiple administrations of BAS at weaning (day 0), days 14, 28, and before transport and feedlot entry (day 42; BAS; RSEA Group, Quartier Salignan, France; n = 9 pens/treatment), or 2) placebo (diethylene glycol monoethyl ether; CON; n = 9 pens/treatment). Treatments (5mL) were applied to the nuchal skin area of each animal during the preconditioning period. Calves within treatment groups were ranked again by initial BW, sex, and age, in a manner that pens have similar initial BW, age, and three steers and two heifers and allocated to 1 of the18 drylot pens. On day 42, calves were combined within the treatment group, loaded into two different single double-deck commercial livestock trailers, and transported for 1,000 km (approximately 16h). Upon arrival (day 43), calves were unloaded at the same feedyard. Blood samples were collected on days 0, 3, 7, 14, 21, 28, 42, 43, 46, 50, 57, 64, and 90. Average daily gain, final BW, and feed efficiency did not differ (P > 0.52) between BAS and CON calves in the preconditioning and receiving phases. A treatment × day interaction was detected (P < 0.001) for plasma haptoglobin concentrations, which was greater (P < 0.01) in CON on days 3 and 7 vs. BAS calves. During the preconditioning phase, serum NEFA concentration was reduced (P < 0.01) in BAS on day 3 compared with CON calves. A treatment × day interaction was detected (P = 0.001) for exit velocity, which was greater (P < 0.001) for CON vs. BAS calves on days 3, 7, 14, and 21 during the preconditioning phase and on day 46 of the receiving phase. Therefore, Applications of BAS reduced immunological responses and exit velocity associated with stress caused by management practices, but did not improve performance during the preconditioning and receiving phases.

EFFECT OF GLYCEROL ON MILK YIELD, ITS QUALITY AND BLOOD PARAMETERS OF HOLSTEIN COWS

The aim of this study was to investigate the effect of adding glycerol at different levels (T1 = control treatment without glycerol, T2 = 75 ml and T3 = 150 ml glycerol) on daily milk yield, milk components and some blood parameters of Holstein cows during the period of 60 days. Milk yield increased significantly (P≤0.05) at 15th day of the experiment, and highly significant (P≤0.01) at 30th and 60th days of the experiment in T3 group. Percentage of milk protein and lactose increased (P≤0.01) in T2 and T3 groups and the percentage of milk fat in the T3 group decreased at day 60 of the experiment. The blood glucose concentration increased (P≤0.01) in T2 and T3 groups at 30 and 60 days of the experiment. Triglyceride concentration increased (P≤0.01) in the blood of T2 and T3 treated cows at day 60. The concentration of cholesterol, NEFA and BHBA decreased (P≤0.01) in T3 treated cows at day 60 of the experiment. The concentration of phosphorous and magnesium were also affected as a result of glycerol treatment. It can be concluded that the addition of dietary glycerol 150 ml / day enhanced milk yield, protein and lactose percentage, and improved blood parameters by increasing blood glucose and reducing NEFA and BHBA concentrations of Holstein cows.