In yearling heifers, WDOT spaying resulted in lower morbidity and short-term mortality compared with flank spaying. Both methods compromised the health and welfare of some animals for up to 4 days and body weight gains were reduced during the 6 weeks post spaying.

The welfare outcomes for Bos indicus cattle (100 heifers and 50 cows) spayed by either the dropped ovary technique (DOT) or ovariectomy via flank laparotomy (FL) were compared with cattle subjected to physical restraint (PR), restraint by electroimmobilization in conjunction with PR (EIM), and PR and mock AI (MAI). Welfare assessment used measures of morbidity, mortality, BW change, and behavior and physiology indicative of pain and stress. One FL heifer died at d 5 from peritonitis. In the 8-h period postprocedures, plasma bound cortisol concentrations of FL, DOT, and EIM cows were not different and were greater (P<0.05) than PR and MAI. Similarly, FL and DOT heifers had greater (P<0.05) concentrations than PR and MAI, with EIM intermediate. Creatine kinase and aspartate aminotransferase concentrations were greater (P<0.05) in FL and EIM heifers compared with the other treatments, with a similar pattern seen in the cows. Haptoglobin concentrations were significantly (P<0.05) increased in the FL heifers compared with other treatments in the 8- to 24-h and 24- to 96-h periods postprocedures, and in cows were significantly (P<0.05) increased in the FL and DOT compared with PR in the 24- to 96-h period. Behavioral responses complemented the physiological responses; standing head down was shown by more (P<0.05) FL cows and heifers to 3 d postprocedures compared with other treatments, although there was no difference between FL and DOT heifers at the end of the day of procedures. At this same time, fewer (P<0.05) FL and DOT heifers and cows were observed feeding compared with other treatments, although in cows there was no difference between FL, DOT, and EIM. There were no significant differences (P>0.05) between treatments in BW changes. For both heifers and cows, FL and DOT spaying caused similar levels of acute pain, but FL had longer-lasting adverse impacts on welfare. Electroimmobilization during FL contributed to the pain and stress of the procedure. We conclude that: i) FL and DOT spaying should not be conducted without measures to manage the associated pain and stress; ii) DOT spaying is preferable to FL spaying; iii) spaying heifers is preferable to spaying cows; and iv) electroimmobilization causes pain and stress and should not be routinely used as a method of restraint.

Bound cortisol responses in spayed heifers were elevated to 6 h post-procedure and similar in WDOT- and flank-spayed animals, indicating comparable levels of pain and stress. An inflammatory response, indicated by haptoglobin concentrations, was sustained for longer in Flank than in WDOT spayed heifers, suggesting longer-lasting adverse effects on welfare from flank spaying than WDOT spaying.

Multiple physiological and neuroendocrine changes consistent with stress and pain have been demonstrated in cattle spayed via the Willis dropped ovary technique (WDOT). The procedure is routinely conducted without the use of anaesthetics or analgesics and has major implications for animal welfare. This study aimed to evaluate the effect of a topical anaesthetic (TA), haemostatic wound dressing, and meloxicam on pain behaviour and haemorrhage in the acute period following spaying. Yearling Brahman heifers (n = 75) were randomly allocated to the following treatment groups: (1) rectal palpation/control (CON); (2) WDOT spay (S); (3) WDOT spay with meloxicam (SM); (4) WDOT spay with TA (STA); and (5) WDOT spay with TA and meloxicam (STAM). Individual behavioural responses, body weight, packed cell volume (PCV), and total plasma protein (TPP) were monitored for up to 24 h following treatment. Head tucking behaviour and tail stiffness was increased in all spay groups compared to the CON group (p < 0.001), with the lowest proportional increase in the SM group. Rumination was initially reduced in S, SM, and STA heifers compared to CON heifers (p < 0.001), though SM heifers ruminated more than S heifers (p < 0.001). CON and SM heifers stood with an arched back the least, spent the most time eating, and spent less time lying down and more time standing compared to other treatment groups (p < 0.001). There was no significant effect of treatment on weight change (p = 0.519), PCV (p = 0.125) or TPP (p = 0.799). The administration of meloxicam is suggested as an effective, currently available method for improving the welfare of cattle undergoing WDOT spaying.