ABSTRACT
A lower nutrient supply from Holstein (HOL) dams to beef fetuses than HOL fetuses has been demonstrated, but the underlying factors remain unclear. We investigated maternal, umbilical vein, and calf blood glucose and amino acid concentrations at calving, along with placental development at term, in HOL dams with similar fetuses (HOL-HOL, n = 12), F1 crosses (HOL × Japanese Black [JB]; HOL-F1, n = 4), JB fetuses (HOL-JB, n = 7), and JB dams with similar fetuses (JB-JB, n = 11). Calf birth weight, total cotyledonary weight, and surface area were greater in HOL-HOL compared to JB-JB or HOL-JB (P < 0.05), whereas those of HOL-F1 were similar. Blood amino acid concentrations in the umbilical veins and calves were similar among HOL-HOL, HOL-F1, and HOL-JB. Calf blood glucose concentrations were lower in HOL-F1 than HOL-HOL (P < 0.05), despite similar maternal blood glucose levels. HOL-JB exhibited higher maternal, umbilical vein, and calf blood glucose concentrations than JB-JB (P < 0.05). Therefore, the glucose supply to the fetus may be inhibited in HOL-F1 due to maternal-fetal breed differences. Higher maternal blood glucose concentrations in HOL-JB may result in elevated fetal glucose exposure, potentially affecting postnatal growth and metabolism.
Subject(s)
Amino Acids , Blood Glucose , Placentation , Animals , Cattle/metabolism , Cattle/embryology , Pregnancy , Female , Blood Glucose/metabolism , Blood Glucose/analysis , Amino Acids/metabolism , Amino Acids/blood , Fetus/metabolism , Birth Weight , Placenta/metabolism , Nutrients/metabolism , Fetal Development , Maternal-Fetal Exchange , Umbilical Veins/metabolism , Animal Nutritional Physiological Phenomena/physiologyABSTRACT
Heifer growth and milk production in lactating cows may diminish the nutrient supply to the fetus. This study aimed to analyze the characteristics of the nutrient supply to the fetus in primiparous and multiparous cows. We investigated maternal, umbilical cord, and calf blood glucose and amino acid levels, as well as placental development in 28 primiparous (PP) and 30 multiparous (MP) Holstein cows. Although the total cotyledonary weight and surface area showed no significant differences, the MP group exhibited larger individual cotyledons (P < 0.01) and fewer medium-sized cotyledons (P < 0.05). Within the PP group, total cotyledonary weight and surface area positively correlated with blood glucose (r = 0.71-0.77; P < 0.01) and total essential amino acid (r = 0.55; P < 0.05) concentrations in the umbilical veins. However, no significant correlation was observed in the MP group. Blood glucose and amino acid concentrations in the umbilical vein, umbilical artery, and calf were significantly lower in the MP group (P < 0.05), although no difference was observed in the dams between the groups. In conclusion, the nutrient status of primiparous cows can alter fetal nutrient supply. Moreover, multiparous cows have larger individual cotyledons as an adaptive response to increased milk production during pregnancy. However, this adaptive response in multiparous cows did not completely restore nutrient supply to the fetus to the same extent as that in primiparous cows. Therefore, the nutritional management of multiparous cows during pregnancy must be reconsidered.
ABSTRACT
We aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on uterine involution and the resumption of ovarian function in dairy cows. Fifty-two multiparous Holstein cows were categorized based on parity and expected calving date and randomly assigned to the RPL or control (CON) groups. The RPL group received 80 g of RPL daily from day 21 before the expected calving date until parturition. Blood samples were obtained twice weekly from pre-supplementation to 6 weeks postpartum. The onset of luteal activity postpartum was determined via ultrasonography twice weekly for up to 6 weeks postpartum. Uterine involution was tracked at 3 and 5 weeks postpartum through the vaginal discharge score, percentage of polymorphonuclear cells (PMN) in endometrial cytology samples, presence of intrauterine fluid, and gravid horn diameter via ultrasonography. Before supplementation, the RPL group showed amino acid imbalance, which was improved by RPL supplementation. There were no significant differences in the onset of luteal activity, percentage of PMN, intrauterine fluid, or the diameter of the uterine horn between the two groups. The vaginal discharge score in the RPL group decreased from 3 to 5 weeks postpartum, whereas that in the CON groups did not decrease. The number of cows with clinical endometritis was lower in the RPL group. Overall, RPL supplementation during the close-up period enhanced vaginal discharge clearance, potentially averting clinical endometritis, but did not affect the first ovulation in dairy cows.
Subject(s)
Cattle Diseases , Endometritis , Vaginal Discharge , Animals , Cattle , Female , Pregnancy , Cattle Diseases/drug therapy , Cattle Diseases/prevention & control , Cattle Diseases/metabolism , Diet/veterinary , Dietary Supplements , Endometritis/prevention & control , Endometritis/veterinary , Endometritis/metabolism , Lactation , Lutein/analysis , Lutein/metabolism , Lysine/pharmacology , Milk/chemistry , Postpartum Period , Rumen/metabolism , Vaginal Discharge/veterinaryABSTRACT
In this study, we aimed to improve current udder health genetic evaluations by addressing the limitations of monthly sampled somatic cell score (SCS) for distinguishing cows with robust innate immunity from those susceptible to chronic infections. The objectives were to (1) establish novel somatic cell traits by integrating SCS and the differential somatic cell count (DSCC), which represents the combined proportion of polymorphonuclear leukocytes and lymphocytes in somatic cells and (2) estimate genetic parameters for the new traits, including their daily heritability and genetic correlations with milk production traits and SCS, using a random regression test-day model (RRTDM). We derived 3 traits, termed ML_SCS_DSCC, SCS_4_DSCC_65_binary, and ML_SCS_DSCC_binary, by using milk loss (ML) estimates at corresponding SCS and DSCC levels, thresholds established in previous studies, and a threshold established from milk loss estimates, respectively. Data consisted of test-day records collected during January 2021 through March 2022 from 265 herds in Hokkaido, Japan. From these records, we extracted records between 7 to 305 d in milk (DIM) in the first lactation to fit the RRTDM. The model included the random effect of herd-test-day, the fixed effect of year-month, fixed lactation curves nested with calving age groups, and random regressions with Legendre polynomials of order 3 for additive genetic and permanent environmental effects. The analysis was performed using Gibbs sampling with Gibbsf90+ software. The averages (ranges) of the daily heritability estimates over lactation were 0.086 (0.075-0.095) for SCS, 0.104 (0.073-0.127) for ML_SCS_DSCC, 0.137 (0.014-0.297) for SCS_4_DSCC_65_binary, and 0.138 (0.115-0.185) for ML_SCS_DSCC_binary; the heritability curve for SCS_4_DSCC_65_binary was erratic. Genetic correlations within the trait decreased as the DIM interval widened, especially for those integrating DSCC, indicating that these traits should be analyzed using RRTDM rather than repeatability models. The averages (ranges) of genetic correlations with milk yield over lactation were 0.01 (-0.22 to 0.28) for SCS, -0.05 (-0.40 to 0.13) for ML_SCS_DSCC, -0.08 (-0.17 to 0.09) for SCS_4_DSCC_65_binary, and -0.08 (-0.22 to 0.27) for ML_SCS_DSCC_binary. Compared with SCS, the newly defined traits exhibited slightly stronger negative genetic correlations with milk yield. Especially in late lactation stages, the genetic correlation between ML_SCS_DSCC and milk yield was significantly below zero, with a posterior median of -0.40. Furthermore, the new traits showed positive correlations with SCS, having estimates varying from 0.68 to 0.85 for ML_SCS_DSCC, 0.14 to 0.47 for SCS_4_DSCC_65_binary, and 0.61 to 0.66 for ML_SCS_DSCC_binary, depending on DIM. Considering that ML_SCS_DSCC and ML_SCS_DSCC_binary have relatively high heritability (compared with SCS) and favorable genetic correlations with milk production traits and SCS, their incorporation into breeding programs appears promising. Nevertheless, their genetic relationships with (sub)clinical mastitis require further investigation.
Subject(s)
Lactation , Mastitis, Bovine , Milk , Animals , Lactation/genetics , Female , Milk/cytology , Cattle/genetics , Mastitis, Bovine/genetics , Cell Count/veterinary , Phenotype , Japan , East Asian PeopleABSTRACT
Immune responses in bovine clinical mastitis (CM) probably differ depending on the causative pathogen and disease severity. The observational study aimed to investigate whether both factors are associated with the dynamics of immune indicators, including somatic cell score (SCS), white blood cell count (WBC), serum albumin/globulin (A/G) ratio, and differential somatic cell count (DSCC). We collected blood and milk samples 0, 3, 5, 7, 14, and 21 days after CM occurred in 38 cows, and grouped the cases (n=49) by disease severity and pathogen. We analyzed data using a linear mixed model considering the effects of pathogens and severity, calculated estimated-marginal means for indicators at each time point, and compared the means between groups. The dynamics of WBC varied depending on both pathogen and severity. WBC changed drastically in either severe or coliform-caused CM, slightly elevated in streptococcal mastitis, but unchanged in staphylococcal mastitis. This possibly relates to the deficiency in innate immune response toward staphylococci. The A/G ratio also changed depending on severity, as it dropped sharply only in severe CM. We observed a non-linear relationship between DSCC and SCS, possibly due to mammary epithelial cells shedding in milk when CM occurred. When cows recovering from Streptococcus dysgalatiae mastitis, DSCC decreased while SCS remained high, suggesting a healing process requiring more macrophages. Our results demonstrate that both the severity and pathogen are associated with immune responses in CM, providing insights into mastitis pathogenesis.
Subject(s)
Cattle Diseases , Mastitis, Bovine , Streptococcal Infections , Female , Cattle , Animals , Milk , Streptococcal Infections/veterinary , Leukocyte Count/veterinary , Immunity , Cell Count/veterinary , Mammary Glands, Animal/pathologyABSTRACT
This observational study aimed to use somatic cell score (SCS) and differential somatic cell count (DSCC), the combined proportion of polymorphonuclear leukocytes and lymphocytes in somatic cells, to investigate how mastitis affected milk production. Using generalized additive models, we analyzed 50,618 test-day records from 8,081 lactations from 7,912 cows in 197 herds between January 2021 and March 2022 to estimate the nonlinear interaction between SCS and DSCC, and the effects of lactation stages and seasons on milk yield, milk component percentages, and milk component yields by parity of cows. The results show that the interaction between SCS and DSCC on these traits was significant, nonlinear, and complex. When DSCC was high, the negative effects of SCS were minimal, even when SCS reached 8 (i.e., 3,200,000 somatic cells/mL). Cows with high DSCC could have milk yields similar to healthy cows, implying that these cows may have been in the early stages of mastitis and that the milk yield had yet to be affected. Contrastingly, when DSCC was low, milk loss due to high SCS was drastic, especially for cows in third or later lactations, whose milk yield could reduce from more than 35 kg/d to less than 15 kg/d (-59.9%). This tremendous milk loss in high-parity cows was likely due to their higher milk yield and higher risks of chronic mastitis. High SCS and low DSCC also led to a pronounced change in milk composition. The decrease in the percentage of lactose can be directly related to the damage of inflammation to the mammary gland, while the increase in fat and protein percentages was more attributable to the concentration effect resulting from the reduced milk yield. Compared with analyses based on categorized SCS and DSCC values, modeling these 2 indices directly helps us more precisely assess mastitis effects on milk yield and milk composition. For efficient milk production, our results indicate that we should prevent high-parity cows from entering a state of high SCS and low DSCC.
ABSTRACT
This study aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on blood metabolites and calf growth. Forty multiparous Holstein dams were selected based on parity, body condition score, and expected calving date, and randomly assigned to a group: with RPL (n = 22) or without (control [CON], n = 18). RPL dams were supplied daily with 80 g of RPL from Day 21 before the expected calving date to parturition. Blood samples were obtained from the dams before the start of supplementation, 1 week before calving, and immediately after calving, and from calves immediately after birth and weekly until 8 weeks of age. Body weight measurements were performed immediately after birth in all calves and at weekly intervals until 8 weeks of age in female calves. No significant difference was observed in serum metabolite levels and plasma amino acid concentrations between the RPL and CON dams before supplementation, whereas plasma lysine concentrations tended to be higher in RPL dams immediately after calving (p = 0.07). Serum total protein levels (p < 0.05) were higher, whereas plasma total amino acid, total essential amino acid, total non-essential amino acid, and other amino acid concentrations were lower in the calves of RPL dams than those of CON dams (p < 0.05). There were no significant differences in calf birth weight between the two groups, although female calves of RPL dams (n = 7) had higher serum total protein (p < 0.05) and tended to have greater body weight (p = 0.09) from 1 to 8 weeks of age than those of CON dams (n = 11). Overall, RPL supplementation during the close-up period may increase placenta-mediated amino acid transfer to the foetus and enhance protein synthesis in the calf, leading to improved weight gain during the suckling period.
Subject(s)
Diet , Lysine , Pregnancy , Animals , Cattle , Female , Lysine/pharmacology , Diet/veterinary , Animals, Newborn , Rumen/metabolism , Dietary Supplements , Body WeightABSTRACT
The California Mastitis Test (CMT) has been used to estimate total somatic cell count (SCC) levels in milk; however, milk with similar SCC levels occasionally shows inconsistent CMT results, which limits the use of the CMT. This observational study aimed to investigate how differential cell counts in milk influence the CMT in Holstein cattle through the novel parameters differential somatic cell count (DSCC) and macrophage proportion (MAC). We performed the CMT on d 0, 3, 5, 7, 14, and 21 after identifying mastitis, and simultaneously measured SCC, DSCC, and MAC at the quarter level. We followed 58 mastitis events occurring in 41 cows and obtained 307 quarter-level records after data cleaning. We transformed SCC to somatic cell score (SCS) and MAC to its logarithm to fit the normal distribution and analyzed the data using the cumulative logit mixed model. Results showed that both an increase in SCS (odds ratio: 3.66, 95% confidence interval: 2.89-4.64) and the logarithm of MAC (odds ratio: 4.35, 95% confidence interval: 1.91-9.91) can contribute to a higher CMT score. During the healing process of mastitis, MAC tends to increase as SCC decreases; thus, even samples with low SCC can cause positive CMT reactions. We recommend that practitioners avoid making treatment decisions based on the CMT alone. We also noted that the CMT is sensitive to subclinical mastitis with high MAC, hence it could be considered an alternative to detecting high MAC (chronic) mastitis.
ABSTRACT
Selective dry cow therapy (SDCT) allocates antibiotics in the dry period to cows or quarters with a high risk of intramammary infection (IMI), potentially improving antibiotic stewardship. However, SDCT has not been used in Japan, possibly due to concerns of negative impacts on udder health. This research aims to evaluate how the SDCT use affected dry period IMI dynamics in Japan. Additionally, the effects of management factors were also considered. At dry-off, 44 cows received antibiotics plus external teat sealant or external sealant in isolation based on their IMI risk, which was assessed using milk culture, a modified California mastitis test (CMT), and mastitis records. The SDCT approach allowed antibiotic use to be reduced by 33.7%. However, quarters with a low risk of infection who received no antibiotics had a numerically higher prevalence of IMI before calving than those who received antibiotics (28.6% vs. 19.2%). In addition, an increased risk of IMI in quarters without antibiotics was also attributed to poor herd hygiene and a shorter duration of external teat sealant adherence. The result suggests that these factors influence the outcome of an SDCT program. Therefore, a uniform recommendation for dry cow herd management may not be optimal.
Subject(s)
Cattle Diseases , Mastitis, Bovine , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Cattle , Cattle Diseases/drug therapy , Cell Count/veterinary , Female , Japan/epidemiology , Lactation , Mammary Glands, Animal , Mastitis, Bovine/epidemiology , Mastitis, Bovine/prevention & control , MilkABSTRACT
The aim of this study was to estimate the associations of the first occurrence of pathogen-specific clinical mastitis (CM) with milk yield and milk composition (somatic cell count (SCC), lactose, fat, protein content in milk and milk urea nitrogen (MUN)). We studied 3149 dairy cows in 31 Hokkaido dairy farms in Japan. Five pathogen groups were studied: Streptococcus spp.; Staphylococcus aureus (S. aureus); coagulase-negative staphylococci (CNS); coliforms; and fungi. Test-day milk data and clinical records were collected from June 2011 until February 2014. Mixed models with an autoregressive correlation structure were fitted to quantify the effects of CM and several other control variables (herd, calving season, parity, week of lactation, and other diseases). Primipara (first lactation) and multipara (second and later lactations) were analysed separately. All pathogens, particularly S. aureus and fungi, were associated with significant milk losses in multipara. In this study, S. aureus and CNS infections were not associated with significant milk loss in primipara. All pathogens, in particular S. aureus and fungi, significantly increased SCC in both parity groups. All pathogens, especially CNS (in primipara) and S. aureus (in multipara), decreased lactose content. All pathogen groups except for fungi were associated with significant changes in fat, protein and MUN. Some pathogens such as Streptococcus spp. and coliforms seemed to be associated with long-term fat, protein and MUN changes. These findings provide estimates that could be used to calculate precise costs of CM, and also provide better indicators of pathogen-specific mastitis.