Minimizing cows' stress when calves were early weaned using the two-step method with nose flaps

Behavioral responses of dairy cows and their calves to gradual or abrupt weaning and separation when managed in full- or part-time cow-calf contact systems

There is growing interest in managing cow and calf together for a prolonged period, but concerns remain about how best to wean and separate the cow and calf to minimize stress. One approach is to progressively reduce suckling opportunity over time, as in nature. There is also interest in part-time contact (suckling for part of the day) to improve milk yield for the farmer and potentially reduce stress at weaning and separation. The primary objective of this study was to compare the behavioral responses of dairy cows to gradual or abrupt weaning and separation, when managed either full or part time with their calves; a secondary focus was the vocal responses of calves under these management conditions. In a 3 × 2 factorial design (n = 14/ treatment), dairy cows and their calves (n = 84 in 7 blocks of 12 cow-calf pairs) were assigned to one of 3 dam-contact treatments at birth: (1) full-time contact between the dam and calf, apart from milking times (total 23 h/d) (2) part-time contact between the dam and calf, between morning and afternoon milking only (total 10 h/d); (3) no contact, where the dam and calf were separated after leaving the maternity pen and had no further contact. At wk 8, one of 2 weaning treatments was assigned: (1) gradual weaning by reduced contact time (50%, then 25% of original dam-contact time in wk 8 and 9, respectively), or gradually reduced milk allowance for no-contact calves (50%, then 25% of estimated 12-L milk intake in wk 8 and 9, respectively) until complete milk removal and dam-calf separation at wk 10; (2) abrupt weaning where milk removal occurred simultaneously with dam-calf separation at wk 10, or only milk removal for no-contact calves. Overall, part-time contact did not reduce weaning and separation distress for cows or calves for either weaning method. Part-time cows showed reduced behavioral responses to separation (greater lying time and less searching behavior), especially on the day of and 24 h after separation, but they showed a similarly strong vocal response to separation as full-time cows. Part-time calves made substantially more high-pitched vocalizations than full-time calves at 24 h after separation. Furthermore, gradual weaning by reducing contact time did not seem to better prepare cows or calves for complete milk removal and separation; most behavioral and vocal responses occurred on the day of separation for gradual-weaning cows and calves, but 24 h later, the reverse occurred for abrupt-weaning cows and there was no difference between gradual- and abrupt-weaning calves. Our results suggest that part-time contact and gradual-weaning conditions likely resulted in hunger and expectation for reunion, which together may have exaggerated behavioral responses at separation. Temporary daily separations may not have increased independence of cow and calf, and the gradual-weaning method here may not have reduced milk intake by calves. These elements are important criteria to facilitate the weaning process, so future work should explore ways to gradually reduce milk intake and promote social independence of cow and calf to minimize weaning distress.

Does Parity Influence the Magnitude of the Stress Response of Nellore Cows at Weaning?

Most studies investigate the impact of stress at weaning on calves; however, little is known about the responses of cows, and whether they would differ according to parity. This study aims to investigate whether parity would influence the weaning stress response in beef cows. Thirty pregnant Nellore cows with their respective calves were randomly allocated to five paddocks and two females from each parity group were placed in the paddocks. There was an interaction (p < 0.05) between parity and evaluation days regarding cortisol, where on d + 7, the higher concentration was observed for multiparous cows. There was an interaction (p < 0.05) between parity and evaluation day for red blood cells (RBC), hematocrit (HCT), and hemoglobin (HB), whereby higher RBC counts on d + 4 were observed for multiparous cows. For HCT and HB, on all post-weaning collection days, higher values were observed for multiparous cows. The day of evaluation had an (p < 0.05) effect on all recorded behaviors, except for rumination (p > 0.05). Nellore cows, regardless of parity, underwent behavioral and physiological changes on abrupt weaning. Physiological parameters indicated that the magnitude of stress was greater in multiparous cows.

Nose-Flap Devices Used for Two-Stage Weaning Produce Wounds in the Nostrils of Beef Calves: Case Report

This case report aims to describe the occurrence of negative impacts of wearing nose-flap devices on beef calves subjected to the two-stage weaning method. Forty-one calves, twenty-one pure Nellore and twenty F1 Angus-Nellore, were weaned on average at 236 days of age. Commercial nose-flap devices were fitted in the nostrils of the calves (d0) to prevent suckling and removed five days later (d5). Individual body weights were assessed at d0 and d5, and average daily gain (ADG) was calculated. At d5, during nose-flap device removal, it was noted that 26.8% of the calves lost the nose-flap device; however, all of them had wounds in their nostrils (no injuries in the nostrils had been observed on d0). To assess the severity of these injuries, an impairment score was assigned to each calf, ranging from 1 = no lesions to 5 = injured with purulent discharge. A logistic regression model was fitted to evaluate the effect of sex and genetic group on nose-flap retention (kept or lost). The retention rate did not differ (p > 0.05) between sex and genetic groups. All calves showed at least open wounds of the nasal septum (score 2), including those that lost the nose-flaps before d5. Almost half of the calves showed weight loss during this period. We conclude that there is a considerable risk of the two-stage weaning method compromising the physical integrity of the nostrils of beef calves through the use of these devices, and due to this, it should not be referred to as a low-stress weaning practice for beef calves.

The Welfare of Beef Cattle in the Scientific Literature From 1990 to 2019: A Text Mining Approach

Beef cattle are the third most numerous terrestrial farmed animals worldwide. Factors such as geographical region, animal category, breed, and rearing system pose specific animal welfare challenges that can have an impact on animal and public health. This article uses text mining (TM) and topic analysis (TA) to explore the scientific literature on beef cattle welfare published in English from 1990 to 2019. Our aim was to reveal the main research topics and their evolution over time. Our analysis showed that the three most relevant themes in research since 1990 have to do with calf behaviour and management, efficiency, and environmental sustainability, and the effects of transport and slaughter on meat quality. Topics showing the most marked increase in the number of papers published deal with stakeholders' perceptions and market opportunities for added-value beef products and risk factors for morbidity and mortality, especially in relation to calf health, antimicrobial use, and antimicrobial resistance. The results indicate a particular focus on the welfare of calves, especially in the veal industry. Pain relief during the castration of calves and bulls also featured prominently. Research is also increasingly assessing aspects of beef cattle welfare that are interlinked to meat quality, the social and environmental sustainability of the sector in relation to market opportunities, and public health. The identified topics represent a basic source of information that can be used for further and more detailed analyses (e.g., systematic reviews) focussed on specific research themes or geographical areas.

Effect of three weaning methods on behavioural, cortisol and weight changes in buffalo calves

Context Calves reared in cow–calf systems separated from their mothers could present various physiological and behavioural changes. Aims The objective of the present study was to examine the effect of different weaning protocols on plasma cortisol concentrations, behavioural responses, and weight gain in water buffalo calves. Methods In total, 40 Murrah buffalo calves (20 males, 20 females) aged 7–8 months and weighing 247.05 ± 33.23 kg were included. The animals were assigned to one of four treatments (10 per group, 5 males, 5 females), as follows: non-weaned calves (NoW); calves weaned abruptly on Day 0 (AW); calves fitted with nose-flaps anti-suckling devices on Day –7 and completely separated from their mothers on Day 0 (NFW); and calves separated from their mothers by a fence line on Day –7 and, then completely separated from their mothers on Day 0 (FENW). Plasma cortisol was measured on Days –7, –6, –4, 0, 1 and 3, while the behavioural variables were measured from Day –7 to Day –4, and from Day 0 to Day 3. The weight of the calves was evaluated on Days –9, –7, 0 and 3. Key results AW calves presented higher cortisol concentrations than did NoW calves (P = 0.0002) and showed a marked increase in walking and decrease in grazing and ruminating on Days 0–3 compared with the other treatments (P &lt; 0.0001). The use of NFW caused behavioural changes after the device placement and after the final separation from the mother (P &lt; 0.0001). In FENW, behavioural changes were observed after the separation by a linear fence but no negative changes were observed after the final separation from the mothers, and positive behaviours such as grazing, rumination and exploration increased. No changes in weight gain were observed (P &gt; 0.05). Conclusions No clear effects were observed in the implementation of alternative weaning, since both NFW and FENW presented changes related to stress at weaning, compared with abrupt weaning. However, in FENW, no behavioural alterations were observed after definitive separation from their mothers. Implications The application of fence-line separation before final separation could be a promising strategy to reduce stress at weaning in water buffalo calves. However, further studies are required to determinate its long-term effect.

Stress and behavioural responses to winter shearing differ between pregnant and non-pregnant ewes

High progesterone concentrations reduce the stress responses in several mammals. Therefore, it may be expected that pregnant ewes have lower responses to stressors than anoestrous ewes. Our aims were to compare the stress response and the behavioural changes of pregnant and non-pregnant ewes sheared during winter. Two trials were with 20 were pregnant (group PR) and 17 non-pregnant ewes (group NP). In the first trial blood samples were collected immediately before and during the first 180 min after shearing, and cortisol, total protein, and albumin concentrations were measured, and globulin concentrations were calculated. In the second trial, the frequency in which each ewe was observed standing, lying down, walking and grazing were recorded from Day -3 to Day -1 (Day 0 = shearing), from Day 1 to Day 5, on Days 13 and 20-21 during 8 h/day. Scan observations were done every 10 min from 8:00 h to 12:00 h and from 14:00 h to 18:00 h (total = 50 recordings.day). Non-pregnant ewes had greater cortisol concentrations than PR ewes (P = .007). Non-pregnant ewes also had greater total protein concentrations than PR ewes (P = .029). Albumin concentration tended to be greater in NP than PR ewes (P = .064). Globulin concentration 30 min after shearing was greater in PR than in NP ewes (P = .047). Pregnant ewes were observed more frequently standing than NP ewes (P = .013). Non-pregnant ewes were observed more frequently lying down and walking than PR ewes (P = .039 and P = .009, respectively). Before shearing, on Day 2 and Day 4, NP ewes walked more frequently than P ewes (P = .007, P < .0001, P = .007 respectively). Pregnant ewes were observed grazing more frequently than NP ewes (P = .009). Pregnant ewes grazed more than NP ewes on Days 1 and 5 (P = .005 and P < .0001 respectively). Overall, we concluded that shearing was a strong stressor that provoked sustained changes in the behavioural pattern, physiological status and gregariousness intensity despite being or not pregnant. Some responses, as cortisol concentration, changes in the time walking and grazing and the decrease of the cohesiveness after shearing seem to be less pronounced in pregnant than in non-pregnant ewes.

Effects of Separation of Cows and Calves on Reproductive Performance and Animal Welfare in Tropical Beef Cattle

Nursing a calf suppresses postpartum ovarian activity prolonging the period of anestrus. Diverse methods are used to reduce the effect of suckling; the most popular, restricted suckling, reduces the number of encounters mother-calf. Temporal weaning of the calf for periods of 24 h, 48 h, or even 72 h also suppress the effect of suckling and is commonly applied to cow-calf operations in the tropics. Early weaning of the calf, usually three to five months after birth, is a practice gaining popularity over the traditional system of weaning at seven months. Furthermore, the use of nose-flaps in the calf to avoid suckling is a common procedure in South America. Finally, weaning during the first week after calving is an established method to reduce postpartum anestrus. The objective of the present review is to discuss the effects of these methods on the reproductive performance of beef cattle and their animal welfare implications.