Systematic early obstetrical assistance at calving: I. Effects on dairy calf stillbirth, vigor, and passive immunity transfer

Abstract

A critical time for dairy cattle is the perinatal period. Good calving management is critical to reduce periparturient losses and ensure the health of the offspring. Generally, it has been recommended that cows be allowed to calve unassisted when possible, but very few studies have been published that support or refute this general guideline. To investigate the effect of early assistance, a clinical trial enrolled 257 Holstein cows that were observed through the second stage of calving and assigned randomly to 1 of 2 calving interventions: not assisted (NA) or early assistance (EA) during the second stage of parturition. Early assistance was given 15min after the first sight of both front hooves of the calf and done using only human force. After calving, the animals were classified into 4 actual calving intervention groups: too quick to be assisted (TQ), NA, EA, and late assistance (LA; for cows in the NA group that did not calve unassisted within the 1h maximum time frame allowed). Giving early assistance to cows during calving as a routine management practice (assigned intervention) did not negatively influence calves' stillbirth risk, vigor at birth, or transfer of passive immunity. Calves in the LA intervention group had significantly greater odds of stillbirth than calves in the NA and EA groups, respectively. Calves in the LA group also had significantly worse vigor at birth than calves in the TQ, NA, or EA groups. Early assistance given at calving to cows that did not present signs of calving difficulties did not adversely affect calves' likelihood of being stillborn, vigor at birth, or transfer of passive immunity.

Quantifying subclinical trauma associated with calving difficulty, vigour, and passive immunity in newborn beef calves

“…A difficult birth can result in a less vigorous neonate, which subsequently leads to a prolonged time to stand and time to suckle from the dam 33–35. The present study is consistent with other studies demonstrating that calves with prolonged or difficult calvings had reduced vigour compared with calves assisted earlier during the parturition process36 or UA calvings 37. Reduced vigour and vitality have been shown to be associated with acidaemia, hypoxia, and elevated L-lactate 5 18.…”

“…Interestingly, only DAs, which likely represent ‘true dystocias’, had significantly elevated blood parameters associated with trauma, reduced vigour, and increased odds of inadequate PI. In situations where the dam’s birth canal is fully dilated, early intervention may indicate a positive management decision to aid in the prevention of calves becoming compromised due to a prolonged calving 36. Although not assessed in this study, it is important to note that the degree of interaction between the dam and the calf may influence the vigour, time to stand, and time to nurse in neonatal calves 49 50.…”

Influence of denaverine hydrochloride on calving ease in Holstein-Friesian heifers

“…Usually, the degree of calving assistance is categorized based on subjective estimates (Hindson, 1978;Tenhagen et al, 2007) and is assessed on 3-to 5-point scales depending on the number of people and the extent of pulling (Meyer et al, 2001;Villettaz Robichaud et al, 2017a). Measuring pulling force with a technical device is more objective.…”

Calving Management: A Questionnaire Survey of Veterinary Subject Matter Experts and Non-Experts

“…Previous studies report diverse protocols of cow movements before parturition. Cows were moved when parturition was considered imminent, either with no time specification [ 60 , 61 ] or the timing of movement was calculated retrospectively, e.g., within 1–4 h prepartum [ 62 ], 4 h before calving [ 63 ], or 48 to 72 h [ 64 ] up to 7 to 5 d before calving [ 65 ].…”

“…Undisturbed calving is essential because the duration of the second stage of parturition determines the course of calving [ 79 ]. Fourteen participants (31.1%) did not consider that, possibly due to the diversity of opinion in the literature [ 60 , 61 , 62 , 63 , 64 , 65 ] or based on their personal experience.…”