Role of mastitis in on-farm deaths of Finnish dairy cows

According to our recent necropsy-based study, mastitis is the most common underlying diagnosis of on-farm deaths in Finnish dairy cows. However, it remained unanswered to what extent mastitis has contributed to death of all necropsied cows. In the present study, based on histopathology, we detected one-third of the necropsied dairy cows having active inflammatory udder lesions (n = 110). The role of mastitis varied and was interpreted by causes of death (underlying, intermediate, immediate, other significant). Mastitis was most commonly the underlying (28%) or both immediate and underlying cause of death (48%), and only seldom was it the immediate (4%) or intermediate (4%) cause of death. Mastitis occurred either as the only cause leading to death (mastitis only, MO; 39%), or with many other contributing diseases (multiple diseases, MD; 61%), which were interacting with mastitis and together leading to death. Between these groups (MO vs. MD), time of mastitis occurrence during lactation, producer-reported duration of illness, clinical signs, and medication differed, as well the histopathologic severity of mastitis. The cases where mastitis was the only initial insult occurred evenly throughout the entire lactation, but the cases with many interacting diseases were clustered in early lactation. In MD cows, cases of mastitis occurred concurrently with metritis (31%), aspiration pneumonia (24%), acute trauma or dystocia (15%), or with other diseases, such as ketosis, hepatic lipidosis, rumenitis, and abomasal diseases. For a pathologist, the gross mastitis diagnosis was most challenging at the beginning of the lactation, especially if inflammation was mild to moderate, suggesting the value of histopathologic examination being highest at that time. Also, producers reported mastitis signs less frequently if cow had many simultaneously occurring diseases. Therefore, even if clinical signs of other diseases are present, the udder should be considered a potential cause of illness and should be examined, especially in dry and transition-period cows

On-farm deaths of dairy cows are associated with features of freestall barns

ABSTRACT On-farm death (OFD) of a dairy cow is always a financial loss for a farmer, and potentially a welfare issue that has to be addressed within the dairy industry. The aim of this study was to explore the associations between OFD of dairy cows, housing, and herd management in freestall barns. To achieve the goal, we followed 10,837 cows calving in 2011 in 82 herds. Data were gathered with observations and a structured interview during farm visits and from a national dairy herd improvement database. The hazard of OFD was modeled with a shared frailty survival model, with SAS 9.3 PHREG procedure (SAS Institute Inc., Cary, NC). The study population was 58% Ayrshire and 42% Holstein cows. The median herd size and mean milk yield in the study herds were 116 cows and 9,151 kg of milk per cow per year. The overall probability of OFD was 6.0%; 1.8% of the cows died unassisted and 4.2% were euthanized. Variation in OFD percentage between individual herds was large, from 0 to 16%, accounting for 0 to 58% of all removals in the herds. Keeping close-up dry cows in an own group was associated with higher hazard of OFD [hazard ratio (HR) = 1.37] compared with keeping them in the same pen with far-off dry cows. Higher hazard on OFD was observed when barns had only one kind of calving pens; single (HR = 2.09) or group pens (HR = 1.72), compared with having both of those types. The hazard of OFD was lower if the whole herd was housed in barns or pens that had only 1 type of feed barrier at the feed bunk, namely post-and-rail (HR = 0.51) or a type with barriers between the cow's heads (HR = 0.49), compared with having 2 types. Lower OFD hazard was observed with wider than 340 cm of walking alley next to the feeding table (HR = 0.75), and with housing a whole herd in pens with only 1 type of walking alley surface, specifically slatted (HR = 0.53) or solid (HR = 0.48), compared with having both types. The hazard of OFD was higher with stalls wider than 120 cm (HR = 1.38) compared with narrower stalls. The hazard of OFD was also associated with breed, parity, and calving season. This study identified many factors that contribute to the incidence of OFD of dairy cows. The solutions for reducing on-farm mortality include housing, management, and breeding choices that are most probably herd specific.Peer reviewe

Dry-off and dairy cow udder health and welfare : Effects of different milk cessation methods

The cessation of milking at the end of lactation is a routine management practice in dairy herds, and the importance of the dry period for milk production and udder health, has long been recognized. Among countries and herds, drying-off practices differ and include various milk cessation methods, such as changes in milking frequency and in feeding, the use of antibiotic dry cow therapy and teat sealants, and changes in housing. Published studies reporting methods of stopping milk production are scarce, and there are no uniform recommendations on optimal procedures to dry cows off for good udder health, cow welfare, and milk production. This review describes methods to stop mik production to prepare cows for the dry period and their effects on mammary involution, udder health, and dairy cow welfare. Milk yield at dry-off (the final milking at the end of lactation) is important for rapid involution, which stimulates the immune system and promotes good udder health and cow welfare. Based on the findings of this review, gradual cessation of milking over several days before the final milking can effectively reduce milk yield at dry-off and accelerate mammary gland involution while maximizing cow comfort and welfare. Data from this review indicate a target production level of 15 kg/day of milk or less at dry-off. (c) 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Prediction of parturition in Holstein dairy cattle using electronic data loggers

The objective of the present study was to assess the effect of parturition on behavioral activity [steps, standing time, lying time, lying bouts (LB), and duration of LB] 4 d before calving using electronic data loggers. Animals (n = 132) from 3 herds were housed in similar freestall barns using a prepartum pen 21 d before the expected calving date and were moved into a contiguous individual maternity pen for parturition. Electronic data loggers were placed on a hind leg of prepartum heifers (heifers, n = 33) and cows (cows, n = 99) at 7 ± 3 d before the expected calving date and removed at 14 ± 3 d in milk. Calving ease (scale 1–4), parity, calving date and time, and stillbirth (born dead or died within 24 h) were recorded. The number of steps (no./d), standing time (min/d), lying time (min/d), number of LB (no./d), and duration of LB (min/b) were recorded. Data were analyzed using MIXED procedures of SAS, adjusting for the herd effect. Only cows experiencing unassisted births (calving ease = 1) were included in the study. An activity index was developed to predict calving time. Heifers and cows with unassisted births had significantly higher number of steps and longer standing time, decreased lying time, and more LB of shorter duration 24 h before calving compared with d −4, −3, and −2. Additionally, the number of LB increased as both heifers and cows approached labor starting on d −2 and peaked at the day of calving. The time since the activity index increased over 50% to parturition did not differ between heifers and cows, and the activity index revealed the shift in activity on average 6 h 14 min (range from 2 h to 14 h 15 min) before calf birth. This study provided evidence that heifers and cows approaching parturition showed a similar, but distinct, behavioral pattern that can be observed on average 6 h before calf birth. The potential benefits of electronic data loggers as predictors of parturition along with proactive management practices should improve the overall survival and welfare of both the dam and calf

Molecular epidemiology and extended-spectrum β-lactamases production of Klebsiella pneumoniae isolated from three dairy herds

The objectives of this study were to isolate Klebsiella pneumoniae from different sources in three dairy cattle herds, to use the pulsed-field gel electrophoresis (PFGE) to measure genotypic similarities between isolates within a dairy herd, to verify the production of extended-spectrum β-lactamases (ESBLs) by the double-disk synergy test (DDST), and to use the PCR to detect the main ESBLs subgroups genes. Three dairy farms were selected based on previous mastitis outbreaks caused by K. pneumoniae. Milk samples were collected from lactating cows and from the bulk tank. Swabs were performed in different locations, including milking parlors, waiting room, soil, animal's hind limbs and rectum. K. pneumoniae was isolated from 27 cases of intramammary infections (IMI) and from 41 swabs. For farm A isolates from IMI and bulk tank were considered of the same PGFE subtype. One isolate from a bulk tank, three from IMI cases and four from environmental samples were positive in the DDST test. All eight DDST positive isolates harbored the bla shv gene, one harbored the bla tem gene, and three harbored the bla ctx-m gene, including the bulk tank isolate. Our study confirms that ESBL producing bacteria is present in different locations in dairy farms, and may be responsible for IMI. The detection of ESBLs on dairy herds could be a major concern for both public and animal health

The effect of litter size, parity and farrowing duration on placenta expulsion and retention in sows

The hypothesis was that a prolonged parturition impairs placenta expulsion and can lead to retained placentas in sows. Furthermore, we hypothesized that application of oxytocin around the time of expulsion of the first placental part improves placenta expulsion. We recorded 142 parturitions of 101 Yorkshire x Large White sows. We determined parity, gestation length, number of liveborn and stillborn piglets, farrowing duration (time between first and last piglet) and the outcome variables: number of expelled placental parts, placenta expulsion duration (time between first and last placental part), first placental part expulsion (time between last piglet and first placental part) and last placental part expulsion (time between last piglet and last placental part). The relationship between farrowing duration and each of the outcome variables was investigated using four distinct multivariable models. Use of oxytocin (used in 44 out of 142 parturitions) increased number of expelled placental parts (3.8 ± 0.2 vs. 2.9 ± 0.3; P = 0.035), decreased the placenta expulsion duration (172 ± 44 vs. 328 ± 26 min; P = 0.011) and time of last placental part expulsion (148 ± 48 vs. 300 ± 24 min; P = 0.025). If oxytocin was not used, farrowing duration obeyed a quadratic relationship with the number of expelled placental parts (P = 0.001), placenta expulsion duration (P = 0.002) and time of last placental part expulsion (P = 0.024). If oxytocin was used, number of expelled placental parts was positively associated with number of liveborn piglets (β = 0.2 ± 0.1; P = 0.002) and affected by parity. 5th parity sows expelled more placental parts (4.3 ± 0.4) than 4th (3.2 ± 0.3; P = 0.024) and 3rd parity sows (2.7 ± 0.4; P = 0.008). Furthermore, placenta expulsion duration was positively associated with number of liveborn piglets (β = 18 ± 8 min; P = 0.025). First placental part expulsion was negatively correlated with farrowing duration (β = 0.3 ± 0.1; P = 0.001). Sows that experienced total (no expulsion of placental parts; n = 4) and partial retained placentas (no expulsion of placental parts after birth of the last piglet; n = 4) had longer farrowing durations (1009 ± 275 and 734 ± 136 min) than sows with no retained placentas (369 ± 202 min; P = 0.021 and P = 0.004). The results show that a prolonged parturition impaired and oxytocin improved placenta expulsion in sows. Furthermore, retained placentas occurred in 3–6% of the sows and was correlated with a prolonged parturition.</p