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Total finds per hunting period of English pointers fed two commercial diets during the quail-hunting season.
Source publication
A study was conducted to evaluate the influence of diet on hunting performance of English pointers during the quail-hunting season in southwest Georgia. Twenty-three trained dogs were assigned to two commercially available diets (i.e., Diet A = Eukanuba Premium Performance Formula, The Iams Company, Lewisburg, OH; Diet B = Diamond Premium Adult Dog...
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Introduction:
Obesity is a global concern in dogs with an increasing prevalence, and effective weight loss solutions are required that work in different geographical regions. The main objective was to conduct an international, multi-centre, weight loss trial to determine the efficacy of a dietary weight loss intervention in obese pet dogs.
Method...
Citations
... In T1, the mean concentrations of Mg 2+ and P + decreased after exercise (Table 1). During exercise, there is a greater demand for Mg2+ and P+ as cofactors in skeletal muscle metabolic processes (Davenport et al., 2001). In T2, the concentrations of Mg2+ did not decrease after exercise, possibly due to the supplementation performed. ...
Establishing methods and actions to improve performance and reduce changes during physical activity is essential in search and rescue dogs. Studying the changes in search and rescue dogs during working activities and how to correct them can help improve their performance and avoid complications. Six healthy adult dogs, which had participated in search and rescue operations for at least one year, were used. Animals had no evidence of clinical disease nor received any supplement or medication prior to the assessment. Dogs were evaluated before, during, and after exercise and submitted to volume replacement with mineral water (T1) and hydroelectrolytic supplementation (T2). Body temperature (BT), parameters of hydration (body weight, erythrogram, and total protein (TP)), energy indicators (glucose, lactate), electrolytes (K+, Na+, Cl-, P+, Ca2+, Mg2+), and hormone levels (cortisol, aldosterone, insulin) were determined. After exercise, isotonic dehydration was detected in both treatments, accompanied by erythrocytosis and weight loss. During the recovery phase, in both treatments, dogs presented a significant increase in BT and lactate and a significant decrease in insulin, TP, and P+. BT and lactate increased after exercise and returned to basal upon recovery. Insulin decreased after exercise without changes in glucose. The maintenance of cortisol indicated the adjustability of dogs to environmental stimuli and stress resistance, and aldosterone did not change during exercise. Both volume replacement with water or hydroelectrolytic and energetic supplementation can correct the isotonic dehydration exhibited by dogs.
... Hunting performance was measured in 23 English pointers fed one of two commercial foods (9). The trial was carried out during the quail-hunting season at a hunting plantation in southwest Georgia. ...
Trade foods for hunter-helper dods
... Davenport et al. 35 examined the effects of high-intensity hunting exercises on serum biochemical variables and found significant changes in MCV, phosphorus, and chloride levels. Similar results were found in a study by Angle et al. 36 , which included 18 healthy mixed-breed sled dogs. ...
Purpose:
Exercise is a fundamental way to maintain and improve health and physical fitness. Many human studies have demonstrated the beneficial effects of exercise on various biological parameters. However, studies investigating the effects of exercise in dogs are limited. This review summarized the current data from studies that examined the effects of different exercise conditions (treadmill vs. non-treadmill and acute vs. chronic) on physiological and hematological parameters in dogs.
Methods:
Papers addressing the effects of exercise in dogs published from January 2000 to October 2020 were retrieved from the online databases of Scopus, Google Scholar, and PubMed and were selected and reviewed.
Results:
The exercise conditions differentially affected physiological and hematological responses and adaptation in dogs. Therefore, the development and comprehensive evaluation of scientific exercise programs for dogs are necessary.
Conclusion:
The dog would be a valuable exercise science animal model, and studies aiming at the optimal health, well-being, and quality of life of dogs need to be conducted.
... Dietary adaptations have also been reported to positively affect exercise performance in dogs. Dogs fed diets high in protein and fat (dietary protein > 30%, dietary fat > 40%) have been reported to outperform dogs fed a low-protein, low-fat, and high-carbohydrate diet (dietary protein < 30%, dietary fat < 40%) in areas such as hunting (more successful finds) [15], stamina [16], and decreased risk of injury (8 times lower) [17] during endurance type exercise. The goal of mushers and trainers is to maximize the performance of their dogs, and nutritional solutions may assist and support adaptations to the cardiorespiratory system. ...
Tryptophan (Trp), an indispensable amino acid for dogs, is the precursor of serotonin, a neurotransmitter with a variety of effects throughout the body, including the ability to modulate cardiac and pulmonary activity. This study aimed to investigate the effects of a 12-week incremental exercise regimen and supplemental dietary Trp on heart rate (HR) and respiratory rate (RR) in client-owned sled dogs. Sixteen Siberian huskies were randomly allocated to either treatment or control diet groups. Both groups were fed a control diet (Trp to large neutral amino acid ratio of 0.047:1); however, treatment dogs received a Trp supplement to achieve a Trp to large neutral amino acid ratio of 0.075:1. Every three weeks, external telemetry equipment was used to non-invasively measure and record HR and RR at a resting, working, and post-exercise state in a controlled exercise challenge. A mixed model was used to test differences between diet, activity parameter, and week. Dietary Trp supplementation had no effect on HR or RR. Independent of diet, resting, working, post-exercise HR, and time to recover post-exercise HR decreased from week −1 to week 11 (p < 0.05). Resting HR had the greatest reduction from week −1 to week 11 (21%, p < 0.05). Working RR did not change with exercise (p > 0.10), but rRR and postRR decreased from week −1 to week 11 (p < 0.05). These data suggest that the exercise regimen the dogs were subjected to may have positively impacted the dogs’ capacity to sustain aerobic exercise, whereas Trp supplementation had no effect on HR or RR.
... load. English pointer dogs show no obvious loss in hunting performance during days that are particularly hot and humid(Davenport, Kelley, Altom, & Lepine, 2001). Horses, swine, goats and sled dogs can tolerate their core body temperatures reaching 42 • C(Armstrong, Delp, Goljan, ...
New findings:
What is the central question of this study? Does available comparative data provide empirical evidence that humans are adapted to endurance running at high ambient temperatures? What is the main finding and its importance? Comparing the results of races that pit man against horse, we find that ambient temperature on race day has less deleterious effects on running speed in humans than it does on their quadrupedal adversary. This is evidence that humans are adapted for endurance running at high ambient temperatures. We debate whether this supports the hypothesis that early man was evolutionarily adapted for persistence hunting.
Abstract:
Many mammals run faster and for longer than humans and have superior cardiovascular physiologies. Yet humans are considered by some scholars to be excellent endurance runners at high ambient temperatures, and in our past to have been persistence hunters capable of running down fleeter quarry over extended periods during the heat of the day. This suggests that human endurance running is less affected by high ambient temperatures than it is for other cursorial ungulates. However, there are no investigations of this hypothesis. We took advantage of longitudinal race results available for three annual events that pit human athletes directly against a hyper-adapted ungulate racer, the thoroughbred horse. Regressing running speed against ambient temperature shows race speed deteriorating with hotter temperatures more slowly in humans than horses. This is the first direct evidence that human running is less inhibited by high ambient temperatures than for another endurance species, supporting the argument that we are indeed adapted for high temperature endurance running. Nonetheless, it is far from clear that this capacity is explained by an endurance hunting past because in absolute terms; humans are slower than horses and indeed many other ungulate species. While some human populations have persistence hunted (and on occasion still do), the success of this unlikely foraging strategy may be best explained by the application of another adaption - high cognitive capacity. With dedication, experience and discipline, capitalising on their small endurance advantage in high temperatures, humans have a chance of running a more athletic prey to exhaustion. This article is protected by copyright. All rights reserved.
... In this study, having collected no behavioral data, we are not able to distinguish the emotional component from the physical effort for the GDB during the whole training period. Hill et al. (2009) reported that a low-carbohydrate/high-protein and fat diet had the potential to be beneficial to working dogs because it is not only closer to the ancestral diet (Case, 2005) but also appeared to confer advantages to working dog performance subjected to prolonged bouts of exercise requiring a sustained energy source (Davenport et al., 2001). Kronfeldet al. (1977) suggested that carbohydrates are not necessary in endurance dog diet. ...
We compared the effects of different feeding strategies on hormonal and oxidative stress biomarkers in guide dogs during a specialized training programs.
Eight neutered adult dogs belonging to the Labrador retriever breed were divided during the training work into two homogeneous groups for sex (2 males, 2 females), age (17 months ± 1), initial body weight (26.3 kg ± 1) and BCS (4.5 of 9 ± 0.11), and fed two commercial diets with different concentration of energetic nutrients. One diet was a performance diet (HPF) characterized by low-carbohydrate/ high-protein and fat content (29:39:19 % as-fed) and the other a normal maintenance diet (LPF), characterized by high-carbohydrate/ low-protein and fat content (50:24:12 % as-fed). The trial lasted 84 days. At Days 0, 28, 56 and 84, 180 min before the training work (T0) and immediately after (T1) and after 120 min (T2), blood ACTH (Adrenocorticotrophic hormone), cortisol, d-ROMS (Reactive Oxygen Metabolites- derived compounds) and BAP (Biological Antioxidant Potential) were evaluated studied. Lactate was measured at T0 and T1. The statistical model included the effects of Diet (HPF vs. LPF), time (from Day 0 to Day 84, end of the trial), and exercise (T0, T1 and T2) and their interaction.
ACTH (P=0.002) and cortisol (P=0.013) showed higher values in the HPF than the LPF group; there were no significant differences were observed for lactate. Time showed no significant difference for any hormones or blood lactate. Exercise significantly (P<0.001) influenced ACTH and cortisol concentrations, showing higher values at T1 than T0 and T2, and with lactate higher (P<0.0001) at T1 than T0. Diet did not influence biomarkers of oxidative stress. Time significantly (P<0.05) influence BAP results but not d-ROMs. Exercise had no effect on BAP results, but d-ROMs were higher at T0 than T2 (P=0.001). There was no interaction effect.
The pituitary-adrenal (HPA) axis response and the oxidative stress indices could represent an objective method to identify optimal dietary protocols for creating a successful guide dog during the early training period.
... Due to the high energy expenditure of hunting dogs [51], care must be taken to avoid dogs becoming underweight [27]. Although most pig hunters feed their dogs commercial diets [12], not all such diets are suitable for hunting dogs [86]. In addition, many hunters choose to supplement commercial diets with, or feed entirely, raw game such as feral pig and kangaroo [12,31]. ...
Hunting feral pigs using dogs is a popular recreational activity in Australia. Dogs are used to flush, chase, bail, and hold feral pigs, and their use for these activities is legal in some states and territories and illegal in others. However, there is little knowledge about the health and welfare of dogs owned specifically for the purpose of pig hunting. We conducted a review of the literature on working dogs in Australia and overseas to determine the likely welfare impacts confronting pig-hunting dogs. We identified numerous challenges facing pig-hunting dogs throughout their lives. Risks to welfare include overbreeding, wastage due to behavioural incompatibilities, the use of aversive training techniques including electronic shock collars, solitary kenneling and tethering, high exposure to infectious diseases including zoonotic diseases, inadequate vaccination and anthelmintic prophlyaxis, high incidence of traumatic and other injuries during hunts, climatic exposure during transportation, mortality during hunts, and a suboptimal quality of life after retirement. There are also significant welfare concerns for the wild pigs hunted in this manner. We conclude that research needs to be conducted in order to determine the current health and welfare of pig-hunting dogs, specifically in Australia. The humaneness of this method of pest control urgently requires further assessment.
... Similarly, certain hot climate canids, such as salukis, have short-term physiological adaptations that allow them to tolerate extreme temperatures (44-47°C [111-116°F]) (Krausz et al., 1978). Unspecialized dogs, however, are particularly susceptible to thermal fluctuations resulting from ambient temperatures and are especially prone to overheating in response to exercise-induced hyperthermia (e.g., Davenport et al., 2001;Stanley, 1980). ...
... Dietary modifications can also help mitigate canid metabolic responses to the combined effects of intense work and ambient temperatures (National Research Council, 2006;Wakshlag and Shmalberg, 2014). For example, in biomes characterized by high ambient temperatures (> 22°C) and humidity, high protein diets (> 25%) generally increase canid body heat through SDA (Groenewald 1947), but the ingestion of fat and especially carbohydrates reduces the impacts of exercise-induced hyperthermia (Davenport et al., 2001;Kruk et al., 1987). In general, dogs in cold environments engaged in demanding tasks, such as hauling, for long periods of time perform best with low thermogenic diets containing very high levels of fat (i.e., > 66%) with very little to no added carbohydrates (Kronfeld and Downey, 1981;Loftus et al., 2014;Orr, 1966; but see Wyatt, 1963). ...
... In general, dogs in cold environments engaged in demanding tasks, such as hauling, for long periods of time perform best with low thermogenic diets containing very high levels of fat (i.e., > 66%) with very little to no added carbohydrates (Kronfeld and Downey, 1981;Loftus et al., 2014;Orr, 1966; but see Wyatt, 1963). In less extreme environments, dogs involved in moderate exercise such as pulling loads or sprinting short distances can be maintained on mixed diets (Kruk et al., 1987;Wakshlag et al., 2009), but those high in fat (> 30%) are also recognized as providing beneficial support for dogs engaged in activity for only a few hours (Davenport et al., 2001;Wakshlag and Shmalberg, 2014). ...
... The increase in phosphorous in the ER dogs is unlikely attributable to any known physiological mechanism associated with exercise, particularly considering the strong correlation between serum CK and serum phosphorus observed. Normally phosphorous concentrations have been shown to mildly drop in similar racing conditions, as well as in shorter-duration moderate intensity exercise such as simulated search and rescue field work, hunting dogs and foxhounds which is attributed to increased glucose metabolism and metabolic demand of skeletal muscle during work (28)(29)(30). Mckenzie et al. (3) did not show any significant changes in phosphorous over time in a simulated 500 mile ultramarathon while taking blood samples every 100 miles. Based on these previous studies, it is reasonable to expect no change or a physiological decrease in phosphorous in exercising sled dogs running. ...
Serum muscle enzymes in endurance sled dogs peak within 2–4 days of racing. The object of this study was to compare mid-race serum chemistry profiles, select hormones, markers of inflammation, and the acute phase response in dogs that successfully completed half of the 2015 Yukon Quest sled dog race to their pre-racing samples (n = 14), as well as mid-race samples of successful dogs to those who developed clinical exertional rhabdomyolysis (ER) (n = 5). Concentrations of serum phosphorus in ER dogs were significantly elevated compared to healthy dogs (median 5.5 vs. 4.25 mg/dL, P < 0.01) at mid race. ALT, AST, and CK show a significant increase from pre-race baseline to mid-race chemistries (P < 0.01), with more pronounced increases in dogs with ER compared to healthy racing dogs (CK- median 46,125 vs. 1,743 U/L; P < 0.01). Potassium concentrations were significantly decreased from pre-race baselines in all dogs (median 5.1 vs. 4.5 mEq/L; P < 0.01), and even lower in dogs with ER (median 3.5 mEq/L; P < 0.01) mid-race. No changes in serum pro-inflammatory cytokine concentrations were noted in any groups of dogs. C-reactive protein was elevated in both groups of dogs, but significantly higher in those with ER compared with healthy dogs mid-race (median 308 vs. 164 ug/mL; P < 0.01). Healthy dogs may have CK elevations over 10,000 U/L, and dogs with ER were over 30,000 U/L. Although potassium decreases in healthy endurance sled dogs during racing, it remains in the normal laboratory reference range; however ER dog potassium levels drop further to the point of hypokalemia. Lastly increases in CRP may be reflective of a physiological response to exercise over the course of a race; however high CRP in ER dogs may be capturing an early acute phase response.
... Olfaction acuity was not measured in this study. Conversely, hunting find rates in English Pointers improved in dogs fed a higher protein, higher fat (31:21%) diet, as compared to a diet containing lower protein and fat (26:17%) (79). Thermal recovery was not investigated. ...
The impact of health, management, and microbiota on olfactory function in canines has not been examined in review. The most important characteristic of the detection canine is its sense of smell. Olfactory receptors are primarily located on the ethmoturbinates of the nasal cavity. The vomeronasal organ is an additional site of odor detection that detects chemical signals that stimulate behavioral and/or physiological changes. Recent advances in the genetics of olfaction suggest that genetic changes, along with the unique anatomy and airflow of the canine nose, are responsible for the macrosmia of the species. Inflammation, alterations in blood flow and hydration, and systemic diseases alter olfaction and may impact working efficiency of detection canines. The scientific literature contains abundant information on the potential impact of pharmaceuticals on olfaction in humans, but only steroids, antibiotics, and anesthetic agents have been studied in the canine. Physical stressors including exercise, lack of conditioning, and high ambient temperature impact olfaction directly or indirectly in the canine. Dietary fat content, amount of food per meal, and timing of meals have been demonstrated to impact olfaction in mice and dogs. Gastrointestinal (GI) microbiota likely impacts olfaction via bidirectional communication between the GI tract and brain, and the microbiota is impacted by exercise, diet, and stress. The objective of this literature review is to discuss the specific effects of health, management, and microbiota shifts on olfactory performance in working canines.