Effect of different dietary protein levels on goats’ blood parameters of Tswana goats reared in extensive production systems

Abstract

In this study, an experiment was conducted to determine the impact of different dietary protein levels on a goat’s blood parameters. Twenty-four female Tswana weaner goats with similar body weights and ages (3 months old and 10.56±1.28 kg) were used for the experiment. Animals were grouped into three treatment groups of eight goats each in a randomised block design according to live weight. Animals were fed protein 23.51g/kg and energy 8.55g/kg DM and then given Lucerne ad libitum. Blood samples were collected on the first day of the experiment and then weekly until the end of the experiment (365) days. Samples collected were analysed for blood biochemistry a hematologicalcal parameters. Different levels of protein supplementation in goats significantly affected blood glucose, albumin, albuglobulin and urea (P<0.05). It was also noted that hematological parameters were influenced significantly (P<0.05) by the physiological stages of animals. Supplementation of protein influenced blood parameters, which gave an indication of the nutrition and energy status of animals. Incidences of fluctuations in some parameters were observed during this experiment and could have resulted from undetected minor infections, and weather extremities in the study area. The findings revealed that there was no impact on different diet levels of protein supplementation on the health status of animals hence, farmers could be advised to supplement with nutrient density which is cheaper. However, the effects of protein supplementation could also explain the effects on reproduction parameters.

Introduction

Blood is an important medium in assessing the health status of animals [5]. The physiological and pathological conditions of animals can be assessed by hematological and biochemical analyses of blood [21]. Scarcity of good quality roughages and low concentrate prices compared with roughage, thus encouraging the use of concentrate-based diets for goats. The concentration of metabolites and enzymes in blood serum are biochemical values with a strong relationship and physiological events in goats [58]. According to [5], Tswana goats are important domestic animals in some regions, especially Limpopo, South Africa. Furthermore, [36] states that goats contribute immensely to the economy and food security of many smallholder farms in the area. However, their productivity is constrained by a shortage of good quality feed, especially during the long dry season [5]. Blood profiles of animals are particularly sensitive to changes in environmental temperature and are an important indicator of physiological responses to stressing agents in goats. It is an important medium in assessing the health status of animals. According to [14], examining blood for their constituents is used to monitor and evaluate the health and nutrition status of animals. According to [29], hematological, biochemical, and mineral profiles are important to be determined because they provide valuable information about the breed, sex, and health status of animals. There is considerable information about the normal parameters of the blood of domestic animal species, however, the values are expected to vary according to breed, different environmental factors, and different methods of management [49]. According to [48], physiological adaptation and the systemic relationship are widely determined using hematological values. Many authors have reported that biochemical profile shows some changes and blood plasma components vary according to growth requirements, growth requirements, breed, ages [43], environmental factors, management conditions, sexual maturity [45] and the productivity of animals [29]. This experiment was conducted to evaluate the impact of different dietary protein levels on goat minerals and blood parameters.

Materials And Methods

This study, which was approved by the Ethics Committee of the North-West University, Mafikeng Campus, South Africa, was performed in accordance with Animal Health guidelines in terms of care and use of experimental animals. The study was conducted at the Molelwane Farm of the North-West University, Mafikeng Campus, North-West Province, South Africa from March 2014 to February 2015.  Mafikeng is located at 25°52اS and 25°38اE. It is a semi-arid environment with savannah-type vegetation and summer rainfall averaging 540 mm per year. It has one long dry season (winter), from May to October, and a relatively short wet season (summer), from November to February. 

 Experimental design

Twenty-five female Tswana weaner goats, with similar body weight and age (3 months old and 10.56±1.28 kg BW), were bought from local farmers around Mafikeng. The goats were ear-tagged and allowed to adapt for two weeks to the experimental conditions prior to the commencement of the study. All animals were dewormed with an anthelmintic drug (Prodose from Virbac) two weeks before the start of the trial. They were also vaccinated against pulpy kidney, anthrax, and heart water diseases. 

Based on live weight, the animals were randomly allocated into three treatment groups (8 goats per treatment) in a completely randomised design (CRD). The does were penned individually in a well-ventilated pen, supplemented with the level of crude protein 23.51g and energy 8.55g per kg. Goats were also fed a basal diet of hay ad libitum and had free access to fresh water.  

 Feeding and management

Goats were fed with concentrate-based diets once daily (at 09:00 hours) and later given grass ad libitum and had access to water. Feeding allocations and refusal to eat were recorded daily for each goat. Animals were weighed monthly prior to the morning feeding. The goats were bred when they reached sexual maturity and monitored throughout the day. Blood was collected from the goats at 08:00 and further measurements of nutritional metabolites and reproductive hormones. All animals were kept in pens throughout the study (365 days). All animals were kept on the University farm for future students’ practical use.   

Diet and feed supplementation

Animals were supplemented with concentrate mixtures consisting of maize, grass, and soybean meal, informed based on their weight and nutritional requirements as follows: Treatment 1: maintenance X1; Treatment 2: maintenance X 2; and Treatment 3: maintenance X 3 (Webb, 2010). The increment of supplemental diets was based on live weight gain and daily feed consumption. In addition, all animals had free access to drinking water. 

Live weight gain

Animals were supplemented with concentrate mixtures consisting of maize, grass and soybean meal, informed based on their weight and nutritional requirements as follows: Treatment 1: maintenance X1; Treatment 2: maintenance X 2; and Treatment 3: maintenance X 3 (Webb, 2010). The increment of supplemental diets was based on live weight gain and daily feed consumption. In addition, all animals had free access to drinking water. 

Blood collection and analysis

Blood collection was done by a qualified animal health technician through the jugular vein. 10 ml of blood was collected immediately after a restraint to minimise the effect of excitement on the mineral levels of blood, especially phosphorus (McDowell et al., 1982). Blood was collected on the first day of the experiment and every second-week post-feeding into one set of sterilized bottles, containing ethylene-diamine tetra acetic acid (EDTA) as the anti-coagulant.   

Blood samples were then stored for 24 hours at 4°C to allow adequate separation of the serum from the clot. Clotted blood (collected in red stoppered tubes) was centrifuged in a macro centrifuge at 10,000 rpm (revolution per minute) for ten minutes to extract the serum for biochemical analysis and the serum separated from the clot. Care was taken to avoid hemolysis of the samples and to minimise inconsistent mineral levels, especially phosphorus (McDowell et al., 1982). 

Biochemistry 

Total protein (TP), Urea (BUN), Glucose (GLUC), Globulin (GLOB), Triglycerides (TRIG), Cholesterol (CHOL), Lipase (LIPA) and Albumin (ALB) were analysed using Idexx catalyst Dx^tm according to the manufacturer’ s instructions (IDEXX Laboratories, Inc., 2016).

Statistical analyses

Blood nutritional metabolite data were analysed using repeated measures on the procedures of SAS (SAS, 2015) on the General Linear Model (GLM) according to the following linear model:

Where: Yij=observation of the dependent variable ij;

µ = fixed effect of population mean for the variable;

D_i = effect of dietary treatment (i = 4); and 

E_ij = random error associated with observation ij, assumed to be normally and independently distributed. 

Statistical significance was declared at p<0.05. When the analysis of variance revealed the existence of significant difference among treatment means, the probability of difference (PDIFF) option in the LSMEANs  statement of the GLM procedure of SAS (2015) was used to separate the means. The level of significance was set at p<0.05.

Results

This section aimed at assessing the effect of supplementation blood glucose levels on Tswana goats. Effect of dietary protein on blood glucose on Tswana goats is illustrated in Table 1 Protein supplementation had a significant (P<0.05) effect on the glucose concentration over time and between treatments.   Glucose concentrations varied between 3.31 Mmol/L at the beginning of the experiment to 1.28 Mmol/L at the end of the experiment after parturition.  There was a decrease in glucose concentration proportionally in the 3 treatments from week 16 (early puberty and pregnancy to week 24) and recovery was observed until parturitions around week 36.

Effect of Protein supplementation on serum Albumin

Data obtained in this study and presented in Table 2 revealed that protein supplementation to Tswana goats had an impact on serum globulin concentrations. In addition, significant increase (P<0.05) was observed from week 20 with concentrations reaching 35.4;38.1, and 39.2 respectively in the treatment 1, 2, and 3 around week 28 and then a drop around week 32 before an increase again after parturition (week 36). Overall, it was observed that Albumin concentrations were proportional to protein supplementation with higher concentrations observed in treatment 3 followed by treatments 2 and 1.  

Effect of Protein supplementation on serum Albuglobulin

 Data obtained in this study did not show significant differences (P<0.05) in serum albuglobulin concentrations between three treatments of Tswana goats fed with protein at different ratios (Table3).  However, significant differences (P<0.05) were observed with the increase of serum albuglobulin over time in all three treatments respectively 0.70 -0.78: 0.75 -0.78 and 0.61 to 0.80 Mmol/L for treatments 1, 2, and 3 respectively between the week 0 to week 38 (Table 3). Effect of Protein supplementation on serum Urea

Data obtained in this study showed no significant differences (P<0.05) between the three treatments during the period of experimentation. In addition, it was observed that Urea concentrations varied significantly (P<0.05) in all three treatments between the beginning and the end of the experiment with 9.02-13.18: 9.02-14.32, and 9.02-13.33 Mmol/L respectively in treatment 1, 2 and 3 (Table 4). Significant concentrations increase was observed from week 16 reaching a peak at week 24 then a slight decrease around week 28 and then a progressive. The increase from week 32.

Effect of Protein supplementation on serum Total protein

Total serum protein concentration was significantly (P<0.05) affected by protein supplementation over time of the experiment with concentrations varying between 66.3 to 73.5; 66.3 to 73.0 and 66.3 to 71.7 respectively for treatments 1,2 and 3 from week 0 to week 38 of the experiment (Table 5). Significant differences (P<0.05) were observed between the three treatments with higher concentrations recorded respectively in treatments 3; 2 and 1 over the experimental period. An increase in concentration was observed between weeks 16 and 28 with the highest concentrations of 72.9; 70.8 and 76.0 Mmol/L respectively recorded around week 20.   

Effect of Protein supplementation on serum globulin

In this study, it was found that protein supplementation to Tswana goats affected the serum globulin levels over time and significant statistical differences (P<0.05) were observed between the tree treatment over the experimental period with higher concentrations recorded in treatment 3 followed by treatment 2 and 1 respectively (Table 6).

Data obtained revealed serum globulin increase starting at week 4 reaching a peak at 42.3; 41.5 and 45.2 respectively for treatment 1; 2 and 3 at week 20 before declining to reach the lowest around week 28.   

Effect of Protein supplementation on serum globulin

 Lipase concentrations were affected by supplementation of protein in Tswana goats. There was no pattern regarding the concentrations of Serum Lipase over the experimental period. The concentrations increased and decreased between week 8 and 36 (Table 7). No statistically significant differences were observed between the three treatments.

Effect of Protein supplementation on serum triglyceride

Tswana goats supplemented with feed at different concentrations of protein, showed significant variation of Serum triglyceride over the experimental period. It was recorded the increase from week 4 with peak highest concentrations of 0.26; 0.30 and 0.18 respectively in Treatment 1; 2 and 3 recorded on week 16 followed by a decrease around 20 before increasing to stabilise at week 28 and decrease until the end of the experiment (Table 8).

Significant differences (P <0.05) were observed between the three treatments with the control group recording higher levels of serum triglyceride followed by the treatment 2 and 3 respectively.

Results obtained from the experiment supplementing Tswana goats with protein at different concentrations showed that no significant differences between those three treatments all over the experimental period.  However, fit was seen that protein supplementation had significant effect over time on the serum concentration of goats. Concentrations of cholesterol increased progressively in around week 12 and reached the peak at week 24 before decreasing to stabilise at week 28 and then slightly increased afterward (Table 9).

Discussion

Improved feeding and good management practices will ensure the improvement of reproductive performances of Tswana goats. Further, the study will assist farmers in rearing of goats through on-farm trials. The study will create awareness among farmers on protein supplementation feeding in order to improve growth performance and reproductive health of Tswana goats reared in extensive production systems.

Serum biochemistry parameters indicate pathophysiological states that help in identifying pathogenesis and causes of disease [45]. The aim of this chapter was to study the effects of supplementation of feed with different concentrations on Tswana goat’s serum biochemistry. Total protein, serum albumin, serum globulin, and urea are among the important serum biochemical parameters in assessing herd health status [30].

Results obtained showed that the serum glucose in this study ranged between 3.85 to 0.94 Mmol/L during the experiment which was within the normal ranges in goats (Table 1). This means that Protein supplementation in Tswana goats does not have an effect on their blood glucose.

These data were lower than the ones of [50] who in their experiment recorded serum glucose ranging between 2.78-4 Mmol/L. The results of this study are in agreement with the ones reported by [4]; [7] and [52] ranging between 2.78–3.89 Mmol/L in goats. Serum glucose is indicative of energy levels of the animal [14]. In this study, it was noted the blood glucose levels were significantly influenced by the sociological stages of the animal than the variability of Protein supplementation in goats. The significant (P < 0.05) decrease in blood glucose observed between week 16 and 24 of the experiment might be explained by the physiological change which was the beginning of puberty and early pregnancy in all animals and that all animals were put to the buck. The hormonal changes observed during puberty of early pregnancy characterised by the release by the pituitary gland of hormones such as Luteinising Hormone and Folliculo Stimulating Hormone induces stress and energy consumption in the animal. In addition, blood glucose levels can be affected by the adaptation mechanism which is influenced by high ambient temperatures [11]. This can be the case of this study because of high temperature in which the experiment was done.

Data obtained in this study are in line with the ones of [50] who also observed that blood glucose was not affected with the increase of tannin-rich sericea lespedeza inclusion level increased in the diet of Kiko crossed male kids.

In this study, serum albumin is indicative of the liver function in the animal [5] was also fund not to be affected by protein concentration in feed of the three treatments. No significant differences (P < 0.05) were observed between the three groups (Table 2). However, as for the blood glucose, serum albumin was influenced by metabolic and physiological changes in animals. The increase of concentrations observed between 24 and 32 weeks of the experiment were due to the fact that all animals were pregnant. These results are in agreement with the findings of [10]; [44]; [37] and [5] who in their respective experiment did not also observe a significant influence of supplementation on serum albumin of goats.

It is important to mention that albumin is a water-soluble protein found in blood accounting for about 60% of plasma proteins found in the blood. Albumin’s main function in blood is to carry fatty acids, thyroid hormones, and steroids [28]. It can also be used as a binding point for some medications and drugs. According to [5] serum albumin variations could be affected by many factors such as heat haemoconcentration that can take to an increase in its value. This explained also seasonal variations observed in serum albumin concentrations in goats during his experimental study.

The progressive increase of albumin from week 20 to week 36 of the experiment corresponds to puberty and pregnancy physiological stages for goats. This increase cannot be explained but might be due to protein levels in feed. Other of studies [5]; [41] and [58]) have noted similar lar decrease in serum albumin concentration in their respective studies. It is known that the main function is to regulate the Oncotic pressure of blood and that higher albumin levels may be caused by acute infections, burns, and stress from surgery or a heart attack [36]. Hence their increase in this study could have been due to some kind of stress related to physiological changes or environmental effects such as heat that animals may have uncounted during the experiment.

Results obtained showed significant statistical differences (P < 0.05) in albuglobulin concentrations between the three treatments with high concentrations noted in treatment 3 followed by 2 and 1 (Table 3). This led to the conclusion that protein supplementation had an impact on albuglobulin levels in treated goats. No significant differences were observed over time. It is important to mention that there is a correlation between serum proteins, albumin, creatinine, and urea [39].

The study did not find significant differences (P < 0.05) between the three treatments in regard to urea concentrations over the experimental period. However, significant differences were observed between the three (P < 0.05) with Diet three showing higher concentrations followed by diet 2 and 1 respectively (Table 4). The difference showed that protein supplementation to Tswana goats had an effect on the urea concentrations. This differentiation might be explained by the fact that urea is a protein degradation by-product which accumulates in blood if the kidney is affected or if the threshold has been reached. Urea is also known to be a nitrogen source used for the synthesis of proteins in the digestive system. In addition, the concentration of Urea in blood is always indicative of o more efficient utilization of amino acid [7].

However, it was noted that the physiological stages of goat did not significantly influence urea concentration in the treated groups. In addition, it was noted that there was no increase in concentration in treated group over time which could be explained by the fact that urea is used as a source of energy in ruminants as the nitrogen portion of urea is used as the building block for the production of protein by rumen microbes [28].

Data obtained in this study also showed significant correlation between protein supplementation in Tswana goats and total protein concentration in blood. Significant differences (P < 0.05) were observed between the three treatments. Higher concentrations of serum total protein were respectively observed in treatment 3; 2 and 1 during the experimental period. There was a slight increase in Total protein concentration from week 16 to 36 of the experiment which corresponded with puberty and pregnancy while after parturition, significant increase of concentrations was observed in all three treatments (Table 5). These results are in line with the ones of [10]; [3]; [35] who in their studies observed an increase of total protein after parturition in goats and bovine. The increase during post- partum could be explained by the increase of globulin and production of immunoglobulin necessary for the neonate immunity and growth [8]. This showed that there was a correlation between physiological stage and total protein concentrations over time of experiment. Results obtained in this study did correlate with the study of [5] who in their study observed a decrease in serum total protein after supplementing the Karroo leaves to goats.

The study revealed that protein supplementation had effects on serum lipase and globulin concentration in blood same as for serum total protein, between the three treatments. High concentrations were respectively observed in treatment 3, 2 and 1. This difference in concentration could be explained by the supplementation of protein in feed and it know that globulins are large proteins that plays an important role in the immunity of the animal (Table 6). The light increase observed during pregnancy as observed in this study is in correlation with the findings of [16]; and [2] who got similar the total proteins, α1-globulins, β-globulins, γ-globulins and albumin/globulin which could be explained by the stress incurred during pregnancy. This confirms that physiological changes had influences on the Globulin concentrations in Tswana goats [12] concluded also that the pattern of serum protein concentrations could give information regarding the level of dehydration, plasma volume expansion and hepatic function occurring during the peri-partum period including the milking period. Due to high temperatures recorded in the study area, heat stress although animals were having access to water ad-libitum, might explain the increase during the study period. However, [18]; [7] and [55] have also reported a decrease of serum total protein and globulin after the milking period. This could be explained by the fact that during the peri-partum the increase of globulin concentration result in the formation of immunoglobulin [13] and mostly lactation period, lipogenesis and esterification are reduced leading to free fatty acid mobilisation by an increase in in nor-epinephrine and epinephrine secretion.

The findings of this study on serum cholesterol did not show significant differences between the three treatments. Significant decrease observed between week 16 and 28 corresponded with stress and increased energy requirements due to pregnancy and lactation. This also show that protein supplementation did not have effect on serum cholesterol concentration in Tswana goats (Table 9). During energy demand period such as pregnancy and lactation, the decrease in protein, albumin and cholesterol might be due also to catabolism of total protein and supply of energy to the mammary gland [59]. Other authors [6]; [33] believe that level of total serum protein correspond with the survival of kids. This because the serum total protein and immunoglobulin fractions are necessary for the neonate immunity and growth. Results of this study are similar to the one obtained by [40] and [9] who observed total protein and globulin were not significantly influenced by the dietary treatments, and in pregnant does, restricted feeding showed no minor or no changes in the concentrations of serum total protein, triglycerides and cholesterol during the study conducted by [49] (Tables 8 and 9). [21] confirmed that, cholesterol is used to diagnose hepatic damage in domestic animals. He, furthermore, stated that increased cholesterol levels are risk factors for heart, disease, while reduction in serum cholesterol indicates inadequate liver function, malnutrition, stress, decreased nutrient intake and hormonal insufficiency. In addition, other studies have shown that serum levels of cholesterol could be indicative of the absence of dyslipidaemia, also known as hypercholesterolemia [41]. Dietary protein had a significant effect on urea in weeks 12 and 36. These results are not in agreement with the ones reported by [1]. The results showed that there was no significant difference reported in urea concentration in goats during his study. However, the lowest value was reported in diet 3 while diets 2 and 3 possessed the highest values. In week 36 high values were reported in diets 1 and 3, while diet 2 had the lower value of urea. Although significant differences (P < 0.05) were observed between the treatment’s diets on the fore mentioned serum chemistry, it was not attributable to diets effects because they are within the normal range and they are capable of performing their function.

[21] revealed that cholesterol is used to diagnose hepatic damage in domestic animals. He, furthermore, stated that increased cholesterol levels are risk factors for heart, disease, while reduction in serum cholesterol indicates inadequate liver function, malnutrition, stress, decreased nutrient intake and hormonal insufficiency. During the study by in addition, levels of serum cholesterol in animals could be indicative of the absence of dyslipidaemia, also known as hypercholesterolemia. Similar findings were reported by [42] when goats were fed tannin-rich forage.

Conclusion

The aim of this study was to evaluate possible effects of different protein dietary supplementations on blood parameters in Tswana goats over time of treatment. It came from the results obtained that serum glucose, albumin and cholesterol were not affected by different concentrations of protein supplemented to the animals. However, it was observed that serum concentrations were affected by different physiological changes such as puberty, pregnancy, and lactation for all parameters. In addition, this study revealed their significant correlation between serum albuglobulin, urea, total protein, globulin, lipase and triglycerides with protein supplementation and the physiological conditions of the goats. From the study it was concluded that supplementation of Protein influenced blood parameters which gave an indication of the nutrition and energy status of animals.   The values of all the measured parameters in blood metabolites/chemistry are comparable and fell within the normal range of the values reported elsewhere. Incident of fluctuations in some parameters were observed during this experiment and this might resulted from undetected minor infection, weather extremities and poor management in the research area.  Furthermore, possible fluctuation reported in this experiment might be due to failure to adaptation of research animals to supplements resulting in malnutrition. Cases of trauma and stress reported here due to theft are also possible explanation of the fluctuation of the measured parameters. These findings indicate that there is no impact on different diet levels of protein supplementation on the health status of the animal hence the communal farmers can be advised to supplement with treatment 1 since it contains less nutrients density therefore it might be cheaper. However, the effects protein supplementation on health status of goats can also explain the effects on the reproduction parameters. It is, therefore, imperative to measure the effect of protein supplement on reproduction to ensure that no negative effects are imparted to the reproduction parameters.

In this study goats were randomly selected and evenly distributed and supplemented with different concentrations of protein. The impact on blood biochemistry changes were assessed and results obtained showed that protein supplementation had significant effect on Albumin, albuglobulin, total protein urea and cholesterol. However, no effects were observed on glucose, lipase, and triglyceride. In addition, it was observed that, physiological changes in the life of the animal affected significantly all the biochemical parameters of the animal. This was also a major finding of this study. The conclusion was that blood biochemistry parameters would clearly give the nutritional; status of the animal and that protein supplementation in animal would have benefit for the animal if done for a long period to allow the animal to adapt and respond to the changes.

Recommendations

The adoption of improved supplementary feeding practices by the communal farmers may be improved by creating awareness among goat reared through on-farm trials and participatory approaches. Future studies on the supplementation feeding by the goat farmers in the study areas can be carried out to assess impact of different dietary protein levels on blood parameters of Tswana goats in semi- arid area of North West Province of South Africa.

Abbreviations

CBR:  Complete randomised design, EDTA: Ethylene-diamine tetra acetic acid, GLM: General Linear Model, Total protein: TP, Urea: BUN, Glucose: GLUC, Globulin: GLOB, Triglycerides: TRIG, Cholesterol: CHOL, Lipase: LIPA and Albumin: ALB,

Declarations

Author contributions

MT collected blood samples, performed data analysis and wrote manuscript, MM conceived, design the study, and reviewed the manuscript. All authors have read and approved the manuscript.

Acknowledgements 

The author thanks all who participated in the study, Animal Health Department staff from North West University. The communal farmers of three villages, Ramatlabama, Tsetse and Lokaleng around Mafikeng are also acknowledged.

Competing interests/ disclosure of interests

No conflict of interest to be declared by authors.

Funding

I am grateful to the North-West University Emerging Researcher and HWSETA, for the financial support during my studies. 

Availability of data and materials

The data sets generated during this study are available and obtainable from the corresponding authors on reasonable request.

Ethics approval 

The study was approved after consideration by the Animal Research Ethics Committee after being reviewed by the North-West University Research Ethics Regulatory Committee (NWU-RERC), Mafikeng Campus, South Africa. Ethics number:  NWU-00019-14-S9.

References

1. Oyewole B., Osigbodi1* E., Joseph O., and Akoh A.A. (2020) Flock ownership pattern of goats in Idah local government area of Kogi State, Nigeria Biological and Pharmaceutical Sciences, 10(3), 118-125.
2. Arfuso, F., Fazio, F., Rizzo, M., Marafioti, S., Zanghì, E.and Piccione, G., (2016) Factors affecting the hematological parameters in different goat breeds from Italy. Journal of Animal Science. (16): 743-757.
3. Bakunzi, F.R, Motsei, L., Nyirenda, M., Ndou, R. & Dzoma, B., (2019) The effect of dicalcium phosphate supplement in summer and winter seasons as reflected on bone and blood phosphorus, calcium and magnesium levels in range breeding beef cattle. Journal of Agriculture and Biodiversity Research, (1): 60-64.
4. Benjamin, M.M., (2020) Outline of Veterinary Clinical Pathology. 3rd edition. USA: Iowa State University Press, 55-75.
5. Brown, D., N’gambi, J.W. & Norris, D., (2016) Feed potential of acacia karroo leaf meal for communal goat production in Southern Africa: The Journal of Animal & Plant Sciences, 26(4): 1178-1186.
6. Chen, M., Mirzaei, A., Nazifi, S. & Shabbooie, Z., (2021) Changes in Digestive Microbiota, Rumen Fermentations and Oxidative Stress around Parturition Are Alleviated by Live Yeast Feed Supplementation to Gestating Ewes. Journal of Fungi 7, 447.
7. Coles, J., 1986. Mechanisms responsible for parturition; the use of experimental models. Animal of Reproduction Science, (83): 567-581.
8. Damptey, J.K. Obese, F.Y. Aboagye, G.S. Ayim-Akono, M. & Ayizanga R.A., (2019) Blood metabolite concentration, milk yield, resumption of ovarian activity and conception in grazing dual purpose cows supplemented with concentrate during the post‐partum period. Journal of Animal Science, 44 (1): 1-8.
9. Goat farmers’ production objectives and trait preferences in the North West province of South Africa: An approach to identify selection criteria for community-based breeding programs (2020) International Journal of Livestock Production 12(2), 64-75.
10. Diogenes, P.V.A., Suassuna, A.C., Mendes Ahid, S.M. & Soto-Blanco, B., (2021) Changes in the Serum Protein Fractions in Goats after Treatment of Natural Gastrointestinal Parasite Infections. Journal of Animal Veterinary Advance, (9): 1603-1606.
11. El-Tarabany, M. S., El-Tarabany, A.A. & Mostafa, A.A., (2016) Physiological and lactation responses of Egyptian dairy Baladi goats to natural thermal stress under subtropical environmental conditions. Introduction to Journal of Biometeorology, (10):1191-1198.
12. Etim, N.N., Williams M.E., Akpabio,U., & Offiong E.E.A., (2019) Haematological Parameters and Factors Affecting Their Values. Agricultural Science. (2): 37-47.
13. Fatet, A., Pellicer-Rubio, M.T. & Leboeuf, B., (2011) Reproductive cycle of goats. Animal Reproduction Science, (124): 211-219.
14. Gupta, N.S., Briggs, D.E.G., Collinson, M.E., Evershed, R.P., Michels, R., Jack, K.S., & Ancost, R.D., (2007) Evidence for thein situ polymerisation of labile aliphatic organic compounds during the preservation of fossil leaves: Implications for organic matter preservation. Organic Geochemistry (38): 28–36.
15. Hashemi, M., Zamiri, M.J. & Safdarian, M., (2008) Effects of nutritional level during late pregnancy on colostral production and blood immunoglobulin levels of Karakul ewes and their lambs. Small Ruminant Research, (75): 204-209.
16. IDEXX Laboratories Inc. (2010) Available at www.idexx.co. (Accessed 23.3.2010).
17. Iriadam, M., (2007) Variation in certain haematological and biochemical parameters during the late peri-partum period in kilis does. Small Ruminant Research, (73): 54-57.
18. Jenkin, G. & Young, I.R., (2004) Mechanisms responsible for parturition; the use of experimental models. Animal of Reproduction Science, (83): 567-581.
19. Kabir, F., Sultana, M.S., Shahjalal, M., Khan, M.J. & Alam, M.Z., (2004) Effect of protein supplementation on growth performance in female goats and sheep under grazing condition. Pakistan Journal of Nutrition, (4):237-239.
20. Kaneko, J. J. (1997) Clinical Biochemistry of Domestic Animals. 5th edition. Academic Press Inc., New York, U.S.A., 885-905.
21. Khan, S.A., Epstein, J.H., Olival, K.J., Hassan, M.M., Hossain, M.B., Rahman, M.A. &
22. Elahi, M.F.., (2020) Haematology and serum chemistry reference values of stray dogs in Bangladesh. Open Veterinary Journal, (1): 13-20.
23. Landau, S., Vecht, J. & Perevollots, A., (1993) Effects of two level of concentrate supplementation on milk production of dairy goats browsing Mediterranean shrubland, Small Ruminant Research, (11): 227-237.
24. Laporte-Broux, B., Roussel, S., Ponter, A.A., Perault, J., ChavattePalmer, A. & Duvaux-
25. Ponter, C., (2011) Short term effect of martenal feed restriction during pregnancy on goat kid morphology, metabolism and behaviour. Journal of Animal Science, (89): 2154-2163.
26. Kochapakdee, S.W.S., Pralokarn., Laapetchara, A.S. & Norton, B.W., (1994|) Grazing management studies with Thai goats. Productivity of female goats grazing newly established pasture with varying levels of supplementary feeding: Asian-Australian Journal Animal Science, (7):289-293.
27. MacDowell, L.R., Williams, N.S., Hidiroglou Njeru, H., Hill, C.A., Ochoa, G.M.L. & Wilkinson, N.S., 1982. Vitamin E supplementation for the ruminant. Animal Feed and Technology, (60): 273-296.
28. MacDowell, G.M., (1983) Hormonal control of glucose homoeostasis in ruminants. Nutritional Sociology, (42): 149-167.
29. Madan, J., Sindhu, S., Gupta, M. & Kumar, S. (2016) Hematobiochemical profile and mineral status in growing beetle goat kids. Journal of. Cell Tissue Research, (16): 5517-5522.
30. Magistrelli, D. & Rosi, F., (2014) Trend analysis of plasma insulin level around parturition in relation to parity in Saanen goats. Journal of Animal science, (92): 2440-2446.
31. Magnus, P.K. & Lali, F.A., (2009) Serum Biochemical Profile of Post-Partum Metritic Cow Veterinary World; 2(1): 27-28.
32. Mellado, M., Valdez, R., Lara,L.M.& Lopez, R., (2008) Stocking rate effects on goats. A research observation. The journal of Range Management, (56): 167-173.
33. Manat, S.A., Roussel, S., Ponter, A.A., Perault, J., ChavattePalmer, A. & Duvaux-Ponter, C., 2011. Short term effect of martenal feed restriction during pregnancy on goat kid morphology, metabolism and behaviour. Journal of Animal Science, (10): 54-63.
34. Manat, S.A., (2016) Vecht, J. & Perevollots, A., 2016. Effects of two level of concentrate supplementation on milk production of dairy goats browsing Mediterranean shrubland, Small Ruminant Research, (11): 27-37.
35. Mauboub, H.D.H., Ramadan, S.G.A., Helal, M.A.Y., & Aziz, E.A.K., (2013) Effect of martenal feeding in late pregnancy on behaviour and performance of Egyptian goat and sheep and their offspring, Global Veterinary, (11): 168-176.
36. Motubatse, M.R., Ng’ambi, J.W., Norris, D. & Malatje, M. M., (2008) Effect of polyethylene glycol 4000 supplementation on the performance of indigenous Pedi goats fed different levels of Acacia nilotica leaf meal and ad libitum Buffalo grass hay. Tropical Animal Health Production, (40): 229–238.
37. Ndlovu, L.R., Forcada, F. & Gonzalez-Bulnes, A., (2014) Hormonal control of reproduction in small ruminants, Animal Reproductive Science, (120): 150-179.
38. Nozad, S., Ramin, A.G. & Moghadam, G., (2012) Diurnal varia-tions in milk urea, protein and lactose concentration Holstein dairy cows. Acta Veterinary Beograd, (61): 3-12.
39. Olafadehan, O.A., Adewumi, M.K. & Okunade, S.A., (2015) Effects of feeding tannin-containing forage in varying proportion with concentrate on the voluntary intake, haematological and biochemical Science indices of goats. Trakia Journal of Science, (1): 73-81.
40. Olafadehan, O.A., Olfadehan, O.O., Adewumi, M.K., Omotugba, S.K. & Daniel, N. E., (2014) Feeding value of differently processed cassava peel meal for weared Rabbits. Proceedings of the 33rd Annual conference of the Nigerian society for Animal Production (NSAP) College of Agricultural Science, Olabisi Onabanjo University Yewa Campus, Ayetoro Ogun State Nigeria, (6): 132-135.
41. Olafadehan, O.A., Olfadehan, O.O., Adewumi, M.K., Omotugba, S.K. & Daniel, N. E., (2011) Change in haematological and biochemical diagnostic parameters of Red Sokoto goats fed tannin-rich Pterocarpus erinaceus forage diets. Veterinary. Achieved, (81): 471- 483.
42. Palacios, M.A. Norbaiyah, B., Cheah, Y.W., Soleimani, A.F., Sazili, A.Q., Rajion, M.A., Goh, Y.M. (2017) Physiological responses in goats subjected to road transportation under the hot, humid tropical conditions. Introduction to Journal of Agricultural Biology, (12): 830–844.
43. Piccione, G., Borruso, M., Fazio, F., Giannetto, C. % Caola, G., (2007) Physiological parameters in lambs during the first 30 days postpartum. Small Ruminant Research, (72): 57-60.
44. Piccione, G., Messina, V., Schembari, A., Casella, S., Giannetto, C., & Alberghina, D., (2011) Pattern of serum protein fractions in dairy cows during different stages of gestation and lactation. Journal of Dairy Research, (4): 421-425.
45. Piccione, G., Messina, V., Vazzana, I., Dara, S., Giannetto, C.and Assenza, A., (2021) Seasonal variations of some serum electrolyte concentrations in sheep and goats. Comprehensive Clinical Pathology, (21): 911-915.
46. SAA. (2021) User’s guide: Statistics version 23. Cary, NC: SAS Institutional, (39)1020-1028.
47. Sadjadian, R., Seifi, H.A., Mohri, M., Naserian, A.A. & Farzaneh, N., (2013) Effects of monensin on metabolism and production in dairy Saanen goats in periparturient period. Asian Australian Journal of Animal Science, (26): 82-89.
48. Shah, K., Khan, F., Rizvi, M. and Sadeeq, U. (2007) Effect of cypermethrin on clinico-haematological parameters in rabbits. Pakistan Veterinary Journal. (27): 171-175.
49. Sharma, A.K. and Kataria, N. (2012) Influence of season on some serum metabolites of Marwari goats. Indian Journal of Small Ruminants, (18): 52-55.
50. Sakha, M., Shamesdini, M. & Mohamad-Zadeh, F., (2008) Blood serum biochemistry values in Raini Goat of Iran. International Journal of Veterinary Medicine, (6):1–7.
51. Solaiman, S.L., Thomas, Y., Dopre, B.R., Min, N., Gurung, T.H. & Haenlein, G.F.W., (2010) Effect of feeding Sericea lespedeza (Lespedeza cuneate) on growth performance, blood metabolites, and carcass characteristics of Kiko crossbred male kids. Small Ruminant Research, (93): 149-156.
52. Smith, J.F., (2018) Reproductive management of grazing Ruminants in New Zealand Sociology of Animal Production, (12): 113-144.
53. Tanaka, S., Itohara, M. Sato, T. Taniguchi, S. & Yokomizo, Y., (2020) Reduced formation of granulomata in gamma (delta) T cell knockout BALB/c mice inoculated with Mycobacterium avium sub species with Para tuberculosis. Veterinary Pathology, (37): 415– 421.
54. Tharwat, M., Ali, A. & Al-Sobsyil, F., (2016) Hematological and biochemical profiles in goats during the transition period. Components Clinical Pathology, (24): 1-7.
55. Tsheole, M. S., Kgobe, B.G., Mwanza, M., Motsei, L.E. & Bakunzi, F.R., (2019) Effect of Phosphorus and Calcium supplementation on growth performance of communally grazed goats in semi-arid area. Journal of Food, Agriculture and Environment 15 (2): 68-73., 2017.
56. Webb E. C. & Mamabolo M. J., (2016) Production and reproduction characteristics of South African indigenous goats in communal farming systems. South African Journal of Animal Science 34, 236-239.
57. Ziaei, N., (2019) Effect of selenium and Vitamin E supplementation on reproductive indices and biochemical metabolites in Raieni goats. Journal of Applied Animal Research, (43):426-430.
58. Zulkifli, I., Norbaiyah, B., Cheah, Y.W., Soleimani, A.F., Sazili, A.Q., Rajion, M.A., Goh, Y.M.(2018) Physiological responses in goats subjected to road transportation under the hot, humid tropical conditions. Introduction to Journal of Agricultural Biology, (12): 840–844.
59. Zvorc, Z., Matijatko, V. B., Beer, J., Foršek, L.J. & Bedrica, K., (2019) Blood serum protein grams in pregnant and non-pregnant cows. Veterinary Book, (70): 21-30.

Tables

Table 1 Effects of dietary protein on serum glucose on Tswana goat 

a,b Means with different superscript on the same row are significantly different (P<0.05). Means without superscripts did not differ (P>0.05)

 Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3. There was a significant difference (P<0.05) between treatment with high concentrations 3.31-1.29 Mmol/L for treatment 3 and 3.31-1.40 and 3.31-1.28 Mmol/L respectively for treatment 2 and 1. 

Table 2 Mean values of serum Albumin concentrations in Tswana goats supplemented with protein at different concentrations (Mmol/L) 

 a,b Means with different superscripts on the same column are significantly different (P<0.05). 

Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3.

Significant differences (P<0.05) in serum concentrations were observed between the three treatments through the period of experiment. 

Table 3 Summary of mean values of serum Albuglobulin variations in Tswana goats supplemented with protein at different concentrations

  a,b Means with different superscript on the same row are significantly different (P<0.05). Means without superscripts did not differ (P>0.05)       Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3. 

Table 4 Summary of mean values of serum urea variations in Tswana goats supplemented with protein at different concentrations

   a,b Means with different superscript on the same row are significantly different (P<0.05). Means without superscripts did not differ (P>0.05)

    Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3 

Table 5 Effects of dietary protein on serum total protein on Tswana goats.

Means without superscripts did not differ (P>0.05)

Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3 

Table 6 Effects of dietary protein on serum globulin on Tswana goats

Means without superscripts did not differ (P>0.05)

Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3 

 Table 7 Effects of dietary protein on serum lipase on Tswana goats

Means without superscripts did not differ (P>0.05)

Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3

 Table 8 Effects of dietary protein on serum Triglycerides on Tswana goats

Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X 3 

Table 9 Effects of dietary protein on serum cholesterol on Tswana goats.

Means without superscripts did not differ (P>0.05)

Treatment 1= maintenance X 1; Treatment 2 = maintenance X 2; Treatment 3 = maintenance X