Body Condition Score Profiles Research Articles

The effect of nutritional management in early lactation and dairy cow genotype on milk production, metabolic status, and uterine recovery in a pasture-based system

High levels of milk production coupled with low feed intake cause negative energy balance in early lactation, especially in the first month postpartum (PP). Therefore, specific nutritional management at this time may improve nutritional and metabolic status with the possibility of contrasting genotypes responding differently. Thus, the objective of this study was to compare the effects of nutritional management strategies and dairy cow genotype on milk production, metabolic status, and some fertility parameters during early lactation in a pasture-based system. Sixty Holstein Friesian cows were blocked on parity and genotype [low-fertility high-milk (LFHM) and high-fertility low-milk (HFLM)] and were randomly assigned to 1 of 2 treatments in a 2 × 2 factorial arrangement, in a randomized complete block design based on calving date, previous 305-d milk yield, and precalving body condition score (BCS). The nutritional management treatments were: (1) ad libitum access to fresh pasture plus an allowance of 3 kg of concentrates per day (CTR, n = 30); and (2) ab libitum access to a tailored total mixed ration (TMR, n = 30). These diets were offered for the first 30 d PP. Following the first 30 d PP, cows fed TMR joined the CTR treatment and were managed similarly until 100 d PP. Blood samples were taken at d 7, 14, 21, and 28 PP to determine metabolic status. Milk samples for composition analysis were collected weekly and BCS assessed every 2 wk. Genotype had a significant effect on milk output, whereas LFHM had increased fat (+0.28 kg/d) and fat-plus-protein (+0.17 kg/d) yield in the first 30 d PP compared with HFLM cows. The LFHM group also exhibited higher protein and lactose yields over the first 100 d PP. Nutritional management did create significant differences in milk composition in the first 30 d: TMR cows had lower protein, milk urea nitrogen, and casein concentration and higher lactose concentration than CTR cows. Over the first 100 d PP, TMR cows had higher fat-plus-protein and lactose yields. Feeding TMR reduced concentrations of nonesterified fatty acids (-0.12 mmol/L) and β-hydroxybutyric acid (-0.10 mmol/L) compared with the CTR group. Cows fed TMR had smaller BCS losses from calving to 60 d PP. There was no effect of any treatment on uterine recovery. Cows in the LFHM group demonstrated greater milk production in the first 30 and 100 d in milk. These results demonstrate that feeding cows a TMR for the first month of lactation has positive effects on milk output, metabolic status, and BCS profile.

INFLUENCE OF BODY CONDITION SCORE ON BLOOD METABOLITES AND OXIDATIVE STRESS IN PRE- AND POST-CALVING OF FRIESIAN DAIRY COWS IN EGYPT

This experiment aimed to study the relation of body condition score (BCS) with blood metabolites in dairy cow. At 8 weeks before expected parturition, 90 multiparous Friesian dairy cows were divided according to their body condition score into 3 groups: Group1: low body condition score (n=30, BCS≤2.58, thinner cows); Group2: medium body condition score (n=30, BCS≤3.12, medium BCS cows); Group3: high body condition score (n=30, BCS≤4.75, obesity cows). The cows BCS, weight and back fat thickness were recorded at -60, -21, -14, -7, 0, 7, 14 and 60 days related to calving time. Blood samples were taken at the time of BCS measurement for determination of β hydroxy butyrate, non-esterified fatty acid, haptoglobin, glucose, triglyceride, albumin, aspartate aminotransferase, cholesterol, superoxide dismutase and malonaldehyde. The results showed a significant decrease in body condition score, body weight and back fat thickness throughout the experimental period accompanied by an increase in β hydroxy butyrate, malonaldehyde and cholesterol. The correlation analysis showed that changed body condition score positively allied with cow weight (r=0.860, P<0.01), back fat thickness (r= 0.977 P<0.01), malonaldehyde (r=0.445, P<0.01) and cholesterol (r=0.342, P<0.01) and was negatively correlated with β hydroxy butyrate (r=0.416, P<0.01), haptoglobin (r=-0.232, P<0.05), non-esterified fatty acid (r=-0.457, P<0.01), albumin (r=-0.133, P>0.05) and aspartate aminotransferase (r=-0.361, P<0.01). Concisely, body condition score loss before and after calving may have significant consequences for blood metabolites, oxidative stress and body condition score profile in dairy cows.Key words: BCS; calving; blood metabolites; Friesian cow

A comparison of serum metabolic and production profiles of dairy cows that maintained or lost body condition 15 days before calving

Body condition score (BCS) change is an indirect measure of energy balance. Energy balance before calving may affect production and health in the following lactation. It is likely that cows may experience BCS loss before calving due to negative energy balance. The objective of this study was to determine if loss of BCS 15d before calving affected milk production, BCS profile, and metabolic status during the transition period and early lactation. On d −15 to d 0 relative to calving, BCS was assessed (1=emaciated, 5=obese) for 98 Holstein-Friesian cows. The cows were divided into 2groups: those that did not lose BCS between d −15 and d 0 (maintained, BCS-M, n=55) and those that lost BCS from d −15 to d 0 (lost, BCS-L, n=43, average loss of 0.29±0.11 BCS). The fixed effects of BCS group, parity, week (day when analyzing milk production records), their interactions, and a random effect of cow were analyzed using PROC MIXED of SAS (SAS Institute Inc., Cary, NC). Before calving, BCS-L cows tended to have higher concentrations of nonesterified fatty acids than BCS-M cows (0.88 vs. 0.78mmol/L). After calving, BCS-L cows had higher nonesterified fatty acid concentrations in wk 1 (0.93 vs. 0.71mmol/L), wk 2 (0.84 vs. 0.69mmol/L), and wk 4 (0.81 vs. 0.63mmol/L) than BCS-M cows. The BCS-L cows had higher concentrations of β-hydroxybutyrate (BHB) in wk 1 (0.72 vs. 0.57mmol/L), wk 2 (0.97 vs. 0.70mmol/L), and wk 4 (0.94 vs. 0.67mmol/L) compared with BCS-M cows. We detected significant reductions in insulin concentrations in BCS-L cows from wk −1 (2.23 vs. 1.37 µIU/mL) to wk 2 (1.68 vs. 0.89 µIU/mL) and wk 4 (2.21 vs 1.59 µIU/mL) compared with BCS-M cows. Prevalence of subclinical ketosis increased in BCS-L cows in wk 3 and 4 when BHB was ≥1.4mmol/L and in wk 1, 3, and 4 when BHB was ≥1.2mmol/L. In wk 1, BCS-L cows tended to have lower levels of calcium than BCS-M cows (2.33 vs. 2.27mmol/L). We found no differences between the groups of cows for milk yield and energy-corrected milk. The BCS-L cows had lower BCS up to 75d in lactation. Overall, BCS-L cows had higher somatic cell scores with an elevated somatic cell score on d 45, d 60, and d 75. There was an overall tendency for BCS-L cows to have higher fat yield and an overall significant increase in fat percentage. Overall, BCS-L cows had lower lactose percentage, with a reduction on d 60. This work shows that BCS loss before calving may have significant consequences for metabolic status, milk composition, somatic cell score, and BCS profile in dairy cows.

Genetic merit for fertility traits in Holstein cows: IV. Transition period, uterine health, and resumption of cyclicity

The objective of this study was to monitor the dry matter intake (DMI), metabolic status, uterine health, and resumption of cyclicity in cows with similar genetic merit for milk production traits but with either good (Fert+) or poor genetic merit (Fert−) for fertility traits. Twenty-six cows were enrolled in the study and data are reported for 15 Fert+ and 10 Fert− cows that completed the study. All cows received a total mixed ration diet during early lactation and were turned out to pasture in late spring. Dry matter intake was recorded daily from wk −2 to 5 relative to parturition. Blood metabolites and metabolic hormones were measured from wk −2 to 8 relative to parturition. Milk production, body condition score, and body weight until wk 35 of lactation are reported. To monitor uterine health, vaginal mucus was scored weekly on a scale of 0 (no pus) to 3 (≥50% pus) from parturition to wk 8 and uterine polymorphonuclear neutrophil count was measured at wk 3 and 6 postpartum. Prepartum DMI was similar between genotypes, but Fert+ cows had significantly greater DMI than Fert− cows (19.7 vs. 16.8kg of dry matter/d) during the postpartum period. Energy balance at wk 1 was significantly greater in Fert+ cows than in Fert− cows [2.3 vs. −1.12 unité fourragère lait (UFL)/d]. The Fert+ cows had significantly greater daily milk solids production (1.89 vs. 1.74kg/d) and tended to have greater daily milk yield (24.2 vs. 22.3kg/d). The Fert+ cows had significantly greater mean circulating insulin-like growth factor-I (102.62 vs. 56.85ng/mL) and tended to have greater mean circulating insulin (3.25 vs. 2.62μIU/mL) compared with Fert− cows from wk −2 to 8 relative to parturition. Mean circulating glucose (3.40 vs. 3.01mmol/L) concentrations were significantly greater in Fert+ cows compared with Fert− cows from wk −2 to 3 relative to parturition. The Fert+ cows maintained significantly greater mean body condition score throughout lactation compared with Fert− cows (2.98 vs. 2.74 units). Moreover, Fert+ cows had better uterine health compared with Fert− cows, as evidenced by lower weekly vaginal mucus scores from wk 2 to 6 postpartum and, based on uterine cytology, smaller proportions were classified as having endometritis at wk 3 (0.42 vs. 0.78) and 6 (0.25 vs. 0.75). Also, a significantly greater proportion of Fert+ cows had resumed cyclicity by wk 6 postpartum (0.86 vs. 0.20) compared with Fert− cows. Hence, we report for the first time that genetic merit for fertility traits is associated with postpartum uterine health status. Superior uterine health and earlier resumption of cyclicity may be mediated through differences in DMI, energy balance, insulin, insulin-like growth factor-I, and body condition score profiles. Importantly, phenotypic improvement in fertility traits was achieved without antagonizing milk production.

Describing the Body Condition Score Change Between Successive Calvings: A Novel Strategy Generalizable to Diverse Cohorts

The objective of this study was to explore the derivation of a mathematical model that adequately describes the intercalving body condition score (BCS) profile in dairy cows and is robust and applicable to different animal cohorts. The data used to generate the function were 75,352 daily BCS records across 3,209 lactations in 1,172 cows from a research herd in New Zealand. Mean daily BCS (scale 1 to 10) across all data were plotted and 4 distinct phases were observed. The functional form used to describe the pattern and quantify its features comprised the sum of the 4 phase functions created from intercepts, rates of change, approximate timing of phase transition points, and the sharpness of these transition points in the BCS profile. The generality and applicability of the described model were tested across substrata of BCS at calving and parity. A second data set consisting of a multiyear study comparing cows fed a total mixed ration (TMR) or grazing fresh pasture was compiled from a different research farm. This data set consisted of 4,112 BCS records from 211 lactations on 95 cows. The third data set was a collation of data from another multiyear experiment comparing animal performance under different stocking rates. The data set consisted of 12,414 BCS test-day records on 564 lactations from 287 cows. The presented model is robust and applicable to different animal cohorts, explaining between 29 and 79% of variation depending on the cohort studied. A notable second period of negative energy balance was evident in all grazing cows during midlactation, irrespective of calving BCS, parity, or stocking rate, but did not appear in cows fed TMR. The amount of BCS lost postcalving and nadir BCS were positively correlated with calving BCS, with fatter cows at calving losing more BCS postcalving but remaining at a greater BCS at nadir. Primiparous cows calved at a greater BCS than multiparous cows, as dictated by management protocols, but they failed to regain BCS postnadir as effectively as their multiparous counterparts. Results may highlight the need for preferential feeding of younger cows during late lactation, at least in grazing systems, to ensure that they achieve the required calving BCS at second calving. Cows receiving TMR lost BCS at a slower rate than cows on pasture but for a longer period; the amount of BCS lost between calving and nadir did not differ between the different feeding treatments. Calving BCS declined with increasing stocking rate, and the rates of both loss and gain were negatively affected by stocking rate. The presented model accurately identified biological attributes of the intercalving BCS profile of different groups of cows.

Holstein-Friesian Strain and Feed Effects on Milk Production, Body Weight, and Body Condition Score Profiles in Grazing Dairy Cows

Data from 113 lactations across 76 cows between the years 2002 to 2004 were used to determine the effect of strain of Holstein-Friesian (HF) dairy cow and concentrate supplementation on milk production, body weight (BW), and body condition score (BCS; 1 to 5 scale) lactation profiles. New Zealand (NZ) and North American (NA) HF cows were randomly allocated to 1 of 3 levels of concentrate supplementation [0, 3, or 6kg of dry matter (DM)/cow per d] on a basal pasture diet. The Wilmink exponential model was fitted within lactation (YDIM = a + b e(−0.05×DIM) + c×DIM). The median variation explained by the function for milk yield was 86%, between 62 and 69% for milk composition, and 80 and 70% for BW and BCS, respectively. North American cows and cows supplemented with concentrates had greater peak and 270-d milk yield. Concentrate supplementation tended to accelerate the rate of incline to peak milk yield, but persistency of lactation was not affected by either strain of HF or concentrate supplementation. No significant strain by diet interaction was found for parameters reported. New Zealand cows reached nadir BCS 14 d earlier and lost less BW (22kg) postcalving than NA cows. Concentrate supplementation reduced the postpartum interval to nadir BW and BCS, and incrementally increased nadir BCS. New Zealand cows gained significantly more BCS (i.e., 0.9×10−3 units/d more) postnadir than NA cows, and the rate of BCS replenishment increased linearly with concentrate supplementation from 0.5×10−3 at 0kg of DM/d to 0.8×10−3 and 1.6×10−3 units/d at 3 and 6kg of DM/d concentrates, respectively. Although there was no significant strain by diet interaction for parameters reported, there was a tendency for a strain by diet interaction in 270-d BCS, suggesting that the effect of concentrate supplementation on BCS gain was, at least partly, strain dependent.